Manuál PHP

Stig Sæther Bakken

Alexander Aulbach

Egon Schmid

Jim Winstead

Lars Torben Wilson

Rasmus Lerdorf

Andrei Zmievski

Jouni Ahto

Sestavil

Stig Sæther Bakken

Egon Schmid

21-07-2002

Copyright

Tento manuál lze redistribuovat podle podmínek GNU General Public License publikované Free Software Foundation; buď verzí 2 této Licence, nebo (dle vašeho uvážení) kterékoliv pozdější verze.

Sekce tohoto manuálu "Rozšíření PHP 4.0" je © 2000 Zend Technologies, Ltd. Tento materiál smí být redistribuován pouze za podmínek specifikovaných v Open Publication License v1.0 neo pozdější (nejnovější verze je v současnosti k dispozici na http://www.opencontent.org/openpub/).

Obsah

Předmluva

I. Začínáme

1. Introduction
2. A simple tutorial
3. Instalace
4. Configuration
5. Security

II. Reference jazyka

6. Základní syntaxe
7. Types
8. Proměnné
9. Konstanty
10. Výrazy
11. Operátory
12. Řídicí struktury
13. Funkce
14. Classes and Objects
15. Vysvětlení referencí (odkazů)

III. Vlastnosti

16. Zpracování chyb
17. Tvorba a úpravy obrázků
18. HTTP autentikace a PHP
19. Cookies
20. Zpracování uploadu souborů
21. Použití vzdálených souborů
22. Obsluha spojení
23. Persistentní databázová spojení
24. Bezpečný režim
25. Using PHP from the command line

IV. Reference funkcí

I. Funkce specifické pro Apache
II. Funkce pro práci s poli
III. Aspell funkce
IV. BCMath funkce pro výpočty s libovolnou přesností
V. Kompresní funkce bzip2
VI. Kalendářové funkce
VII. CCVS API Funkce
VIII. Funkce na podporu COM ve Windows
IX. Funkce pro práci s třídami/objekty
X. ClibPDF functions
XI. Crack functions
XII. Funkce pro práci s CURL, Client URL Library
XIII. Cybercash platební funkce
XIV. Crédit Mutuel CyberMUT functions
XV. Cyrus IMAP administration functions
XVI. Character type functions
XVII. Database (dbm-style) abstraction layer functions
XVIII. Date and Time functions
XIX. dBase functions
XX. DBM Funkce
XXI. dbx functions
XXII. DB++ Functions
XXIII. Direct IO functions
XXIV. Adresářové funkce
XXV. DOM XML funkce
XXVI. .NET functions
XXVII. Error Handling and Logging Functions
XXVIII. FrontBase Functions
XXIX. filePro funkce
XXX. Filesystémové funkce
XXXI. Forms Data Format functions
XXXII. FriBiDi functions
XXXIII. FTP functions
XXXIV. Funkce pro práci s funkcemi
XXXV. GNU Gettext
XXXVI. GMP functions
XXXVII. HTTP funkce
XXXVIII. Hyperwave functions
XXXIX. Hyperwave API functions
XL. ICAP funkce
XLI. iconv functions
XLII. Image functions
XLIII. IMAP, POP3 and NNTP functions
XLIV. Informix functions
XLV. InterBase functions
XLVI. Ingres II functions
XLVII. IRC Gateway Functions
XLVIII. Java
XLIX. LDAP functions
L. Mailové funkce
LI. mailparse functions
LII. Mathematical Functions
LIII. Multi-Byte String Functions
LIV. MCAL functions
LV. Mcrypt Encryption Functions
LVI. Mhash funkce
LVII. Mimetype Functions
LVIII. Microsoft SQL Server functions
LIX. Ming functions for Flash
LX. Smíšené funkce
LXI. mnoGoSearch Functions
LXII. mSQL functions
LXIII. MySQL Funkce
LXIV. Mohawk Software session handler functions
LXV. muscat functions
LXVI. Síťové funkce
LXVII. Ncurses terminal screen control functions
LXVIII. Lotus Notes functions
LXIX. Unified ODBC functions
LXX. Oracle 8 functions
LXXI. OpenSSL funkce
LXXII. Oracle functions
LXXIII. Ovrimos SQL functions
LXXIV. Output Control funkce
LXXV. Object property and method call overloading
LXXVI. PDF funkce
LXXVII. Funkce pro práci s Verisign Payflow Pro
LXXVIII. PHP volby & informace
LXXIX. POSIX functions
LXXX. PostgreSQL functions
LXXXI. Process Control Functions
LXXXII. Funkce Spouštění Programů
LXXXIII. Printer functions
LXXXIV. Pspell Functions
LXXXV. GNU Readline
LXXXVI. GNU Recode funkce
LXXXVII. Regular Expression Functions (Perl-Compatible)
LXXXVIII. qtdom functions
LXXXIX. Regular Expression Functions (POSIX Extended)
XC. Funkce pro práci se semafory a sdílenou pamětí
XCI. SESAM database functions
XCII. Session handling functions
XCIII. Funkce pro práci se sdílenou pamětí
XCIV. Shockwave Flash functions
XCV. SNMP functions
XCVI. Socket functions
XCVII. Funkce pro práci s řetězci
XCVIII. Sybase functions
XCIX. Tokenizer functions
C. URL Functions
CI. Variable Functions
CII. vpopmail functions
CIII. W32api functions
CIV. WDDX funkce
CV. XML parser functions
CVI. XML-RPC functions
CVII. XSLT funkce
CVIII. YAZ functions
CIX. Funkce pro práci s YP/NIS
CX. Zip File Functions (Read Only Access)
CXI. Zlib Compression Functions

V. Extending PHP 4.0

26. Overview
27. Extension Possibilities
28. Source Layout
29. PHP's Automatic Build System
30. Creating Extensions
31. Using Extensions
32. Troubleshooting
33. Source Discussion
34. Accepting Arguments
35. Creating Variables
36. Duplicating Variable Contents: The Copy Constructor
37. Returning Values
38. Printing Information
39. Startup and Shutdown Functions
40. Calling User Functions
41. Initialization File Support
42. Where to Go from Here
43. Reference: Some Configuration Macros
44. API Macros

VI. FAQ: Často zodpovídané otázky

45. Obecné informace
46. E-mailové konference (mailing lists)
47. Získání PHP
48. Záležitosti databází
49. Instalace
50. Sestavovací (kompilační) problémy
51. Používání PHP
52. PHP a HTML
53. PHP a COM
54. PHP a jiné jazyky
55. Přechod z PHP 2 na PHP 3
56. Přechod z PHP 3 na PHP 4
57. Ostatní otázky

VII. Dodatky

A. Historie PHP a souvisejících projektů
B. Přechod z PHP 3 na PHP 4
C. Přechod z PHP/FI 2 na PHP 3
D. Ladění (debugging) PHP
E. Extending PHP
F. Seznam aliasů funkcí
G. Seznam vyhrazených slov
H. List of Resource Types
I. List of Parser Tokens
J. O tomto manuálu
K. missing stuff

Předmluva

PHP, což znamená "PHP: Hypertext Preprocessor", je široce používaný mnohoúčelový skriptovací jazyk, šířený pod Open Source licencí, zvlášť vhodný pro vývoj WWW aplikací a způsobilý pro vkládání do HTML. Velká část jeho syntaxe je vypůjčená z C, Javy a Perlu. Cílem tohoto jazyka je je umožnit webovým vývojářum rychle psát dynamicky generované stránky - ale s PHP můžete dělat mnohem víc!

Tento manuál je tvořen především referenční příručkou funkcí, ale obsahuje také refereční příručku jazyka, vysvětlení hlavních vlastností a možností PHP a různé doplňkové informace.

Manuál si můžete stáhnout v různých formátech na http://www.php.net/docs.php. Soubory ke stažení se aktualizují vždy při změně obsahu. Více informací o tom, jak je tento manuál vytvářen, najdete v dodatku 'O manuálu'.

I. Začínáme

Obsah
1. Introduction
2. A simple tutorial
3. Instalace
4. Configuration
5. Security

Kapitola 1. Introduction

What is PHP?

PHP (recursive acronym for "PHP: Hypertext Preprocessor") is a widely-used Open Source general-purpose scripting language that is especially suited for Web development and can be embedded into HTML.

Simple answer, but what does that mean? An example:

Příklad 1-1. An introductory example

<html> <head> <title>Example</title> </head> <body> <?php echo "Hi, I'm a PHP script!"; ?> </body> </html>

Notice how this is different from a script written in other languages like Perl or C -- instead of writing a program with lots of commands to output HTML, you write an HTML script with some embedded code to do something (in this case, output some text). The PHP code is enclosed in special start and end tags that allow you to jump into and out of "PHP mode".

What distinguishes PHP from something like client-side JavaScript is that the code is executed on the server. If you were to have a script similar to the above on your server, the client would receive the results of running that script, with no way of determining what the underlying code may be. You can even configure your web server to process all your HTML files with PHP, and then there's really no way that users can tell what you have up your sleeve.

The best things in using PHP are that it is extremely simple for a newcomer, but offers many advanced features for a professional programmer. Don't be afraid reading the long list of PHP's features. You can jump in, in a short time, and start writing simple scripts in a few hours.

Although PHP's development is focused on server-side scripting, you can do much more with it. Read on, and see more in the What can PHP do? section.

What can PHP do?

Anything. PHP is mainly focused on server-side scripting, so you can do anything any other CGI program can do, such as collect form data, generate dynamic page content, or send and receive cookies. But PHP can do much more.

There are three main fields where PHP scripts are used.

Server-side scripting. This is the most traditional and main target field for PHP. You need three things to make this work. The PHP parser (CGI or server module), a webserver and a web browser. You need to run the webserver, with a connected PHP installation. You can access the PHP program output with a web browser, viewing the PHP page through the server. See the installation instructions section for more information.
Command line scripting. You can make a PHP script to run it without any server or browser. You only need the PHP parser to use it this way. This type of usage is ideal for scripts regularly executed using cron (on *nix or Linux) or Task Scheduler (on Windows). These scripts can also be used for simple text processing tasks. See the section about Command line usage of PHP for more information.
Writing client-side GUI applications. PHP is probably not the very best language to write windowing applications, but if you know PHP very well, and would like to use some advanced PHP features in your client-side applications you can also use PHP-GTK to write such programs. You also have the ability to write cross-platform applications this way. PHP-GTK is an extension to PHP, not available in the main distribution. If you are interested in PHP-GTK, visit it's own website.

PHP can be used on all major operating systems, including Linux, many Unix variants (including HP-UX, Solaris and OpenBSD), Microsoft Windows, Mac OS X, RISC OS, and probably others. PHP has also support for most of the web servers today. This includes Apache, Microsoft Internet Information Server, Personal Web Server, Netscape and iPlanet servers, Oreilly Website Pro server, Caudium, Xitami, OmniHTTPd, and many others. For the majority of the servers PHP has a module, for the others supporting the CGI standard, PHP can work as a CGI processor.

So with PHP, you have the freedom of choosing an operating system and a web server. Furthermore, you also have the choice of using procedural programming or object oriented programming, or a mixture of them. Although not every standard OOP feature is realized in the current version of PHP, many code libraries and large applications (including the PEAR library) are written only using OOP code.

With PHP you are not limited to output HTML. PHP's abilities includes outputting images, PDF files and even Flash movies (using libswf and Ming) generated on the fly. You can also output easily any text, such as XHTML and any other XML file. PHP can autogenerate these files, and save them in the file system, instead of printing it out, forming a server-side cache for your dynamic content.

One of the strongest and most significant feature in PHP is its support for a wide range of databases. Writing a database-enabled web page is incredibly simple. The following databases are currently supported:

Adabas D Ingres Oracle (OCI7 and OCI8)

dBase InterBase Ovrimos

Empress FrontBase PostgreSQL

FilePro (read-only) mSQL Solid

Hyperwave Direct MS-SQL Sybase

IBM DB2 MySQL Velocis

Informix ODBC Unix dbm

We also have a DBX database abstraction extension allowing you to transparently use any database supported by that extension. Additionally PHP supports ODBC, the Open Database Connection standard, so you can connect to any other database supporting this world standard.

PHP also has support for talking to other services using protocols such as LDAP, IMAP, SNMP, NNTP, POP3, HTTP, COM (on Windows) and countless others. You can also open raw network sockets and interact using any other protocol. PHP has support for the WDDX complex data exchange between virtually all Web programming languages. Talking about interconnection, PHP has support for instantiation of Java objects and using them transparently as PHP objects. You can also use our CORBA extension to access remote objects.

PHP has extremely useful text processing features, from the POSIX Extended or Perl regular expressions to parsing XML documents. For parsing and accessing XML documents, we support the SAX and DOM standards. You can use our XSLT extension to transform XML documents.

While using PHP in the ecommerce field, you'll find the Cybercash payment, CyberMUT, VeriSign Payflow Pro and CCVS functions useful for your online payment programs.

At last but not least, we have many other interesting extensions, the mnoGoSearch search engine functions, the IRC Gateway functions, many compression utilities (gzip, bz2), calendar conversion, translation...

As you can see this page is not enough to list all the features and benefits PHP can offer. Read on in the sections about installing PHP, and see the function reference part for explanation of the extensions mentioned here.

Kapitola 2. A simple tutorial

Here we would like to show the very basics of PHP in a short simple tutorial. This text only deals with dinamic webpage creation with PHP, though PHP is not only capable of creating webpages. See the section titled What can PHP do for more information.

PHP-enabled web pages are treated just like regular HTML pages and you can create and edit them the same way you normally create regular HTML pages.

What do I need?

In this tutorial we assume that your server has support for PHP activated and that all files ending in .php are handled by PHP. On most servers this is the default extension for PHP files, but ask your server administrator to be sure. If your server supports PHP then you don't need to do anything. Just create your .php files and put them in your web directory and the server will magically parse them for you. There is no need to compile anything nor do you need to install any extra tools. Think of these PHP-enabled files as simple HTML files with a whole new family of magical tags that let you do all sorts of things.

Your first PHP-enabled page

Create a file named hello.php under your webserver root directory with the following content:

Příklad 2-1. Our first PHP script: hello.php

<html> <head> <title>PHP Test</title> </head> <body> <?php echo "Hello World<p>"; ?> </body> </html>

The output of this script will be:

<html> <head> <title>PHP Test</title> </head> <body> Hello World<p> </body> </html>

Note that this is not like a CGI script. The file does not need to be executable or special in any way. Think of it as a normal HTML file which happens to have a set of special tags available to you that do a lot of interesting things.

This program is extremely simple and you really didn't need to use PHP to create a page like this. All it does is display: Hello World using the PHP echo() statement.

If you tried this example and it didn't output anything, or it prompted for download, or you see the whole file as text, chances are that the server you are on does not have PHP enabled. Ask your administrator to enable it for you using the Installation chapter of the manual. If you want to develop PHP scripts locally, see the downloads section. You can develop locally on any Operating system, be sure to install an appropriate web server too.

The point of the example is to show the special PHP tag format. In this example we used <?php to indicate the start of a PHP tag. Then we put the PHP statement and left PHP mode by adding the closing tag, ?>. You may jump in and out of PHP mode in an HTML file like this all you want.

Something Useful

Let's do something a bit more useful now. We are going to check what sort of browser the person viewing the page is using. In order to do that we check the user agent string that the browser sends as part of its HTTP request. This information is stored in a variable. Variables always start with a dollar-sign in PHP. The variable we are interested in right now is $_SERVER["HTTP_USER_AGENT"].

PHP Autoglobals Note: $_SERVER is a special reserved PHP variable that contains all web server information. It's known as an Autoglobal. See the related manual page on Autoglobals (also known as Superglobals) for more information. These special variables were introduced in PHP 4.1.0. Before this time, we used the older $HTTP_*_VARS arrays instead, such as $HTTP_SERVER_VARS. Although deprecated, these older variables still exist.

To display this variable, we can simply do:

Příklad 2-2. Printing a variable (Array element)

<?php echo $_SERVER["HTTP_USER_AGENT"]; ?>

A sample output of this script may be:

Mozilla/4.0 (compatible; MSIE 5.01; Windows NT 5.0)

There are many types of variables available in PHP. In the above example we printed an Array element. Arrays can be very useful.

$_SERVER is just one variable that's automatically made available to you by PHP. A list can be seen in the Reserved Variables section of the manual or you can get a complete list of them by creating a file that looks like this:

Příklad 2-3. Show all predefined variables with phpinfo()

<?php phpinfo(); ?>

If you load up this file in your browser you will see a page full of information about PHP along with a list of all the variables available to you.

You can put multiple PHP statements inside a PHP tag and create little blocks of code that do more than just a single echo. For example, if we wanted to check for Internet Explorer we could do something like this:

Příklad 2-4. Example using control structures and functions

<?php if (strstr($_SERVER["HTTP_USER_AGENT"], "MSIE")) { echo "You are using Internet Explorer<br />"; } ?>

A sample output of this script may be:

You are using Internet Explorer<br />

Here we introduce a couple of new concepts. We have an if statement. If you are familiar with the basic syntax used by the C language this should look logical to you. If you don't know enough C or some other language where the syntax used above is used, you should probably pick up any introductory PHP book and read the first couple of chapters, or read the Language Reference part of the manual. You can find a list of PHP books at http://www.php.net/books.php.

The second concept we introduced was the strstr() function call. strstr() is a function built into PHP which searches a string for another string. In this case we are looking for "MSIE" inside $_SERVER["HTTP_USER_AGENT"]. If the string is found, the function returns TRUE and if it isn't, it returns FALSE. If it returns TRUE, the if statement evaluates to TRUE and the code within its {braces} is executed. Otherwise, it's not. Feel free to create similar examples, with if, else, and other functions such as strtoupper() and strlen(). Each related manual page contains examples too.

We can take this a step further and show how you can jump in and out of PHP mode even in the middle of a PHP block:

Příklad 2-5. Mixing both HTML and PHP modes

<?php if (strstr($_SERVER["HTTP_USER_AGENT"], "MSIE")) { ?> <h3>strstr must have returned true</h3> <center><b>You are using Internet Explorer</b></center> <?php } else { ?> <h3>strstr must have returned false</h3> <center><b>You are not using Internet Explorer</b></center> <?php } ?>

A sample output of this script may be:

<h3>strstr must have returned true</h3> <center><b>You are using Internet Explorer</b></center>

Instead of using a PHP echo statement to output something, we jumped out of PHP mode and just sent straight HTML. The important and powerful point to note here is that the logical flow of the script remains intact. Only one of the HTML blocks will end up getting sent to the viewer depending on if strstr() returned TRUE or FALSE In other words, if the string MSIE was found or not.

Dealing with Forms

One of the most powerful features of PHP is the way it handles HTML forms. The basic concept that is important to understand is that any form element in a form will automatically be available to your PHP scripts. Please read the manual section on Variables from outside of PHP for more information and examples on using forms with PHP. Here's an example HTML form:

Příklad 2-6. A simple HTML form

<form action="action.php" method="POST"> Your name: <input type="text" name="name" /> Your age: <input type="text" name="age" /> <input type="submit"> </form>

There is nothing special about this form. It is a straight HTML form with no special tags of any kind. When the user fills in this form and hits the submit button, the action.php page is called. In this file you would have something like this:

Příklad 2-7. Printing data from our form

Hi <?php echo $_POST["name"]; ?>. You are <?php echo $_POST["age"]; ?> years old.

A sample output of this script may be:

Hi Joe. You are 22 years old.

It should be obvious what this does. There is nothing more to it. The $_POST["name"] and $_POST["age"] variables are automatically set for you by PHP. Earlier we used the $_SERVER autoglobal, now above we just introduced the $_POST autoglobal which contains all POST data. Notice how the method of our form is POST. If we used the method GET then our form information would live in the $_GET autoglobal instead. You may also use the $_REQUEST autoglobal if you don't care the source of your request data. It contains a mix of GET, POST, COOKIE and FILE data. See also the import_request_variables() function.

Using old code with new versions of PHP

Now that PHP has grown to be a popular scripting language, there are more resources out there that have listings of code you can reuse in your own scripts. For the most part the developers of the PHP language have tried to be backwards compatible, so a script written for an older version should run (ideally) without changes in a newer version of PHP, in practice some changes will usually be needed.

Two of the most important recent changes that affect old code are:

The deprecation of the old $HTTP_*_VARS arrays (which need to be indicated as global when used inside a function or method). The following autoglobal arrays were introduced in PHP 4.1.0. They are: $_GET, $_POST, $_COOKIE, $_SERVER, $_ENV, $_REQUEST, and $_SESSION. The older $HTTP_*_VARS arrays, such as $HTTP_POST_VARS, still exist and have since PHP 3.
External variables are no longer registered in the global scope by default. In other words, as of PHP 4.2.0 the PHP directive register_globals is off by default in php.ini. The preferred method of accessing these values is via the autoglobal arrays mentioned above. Older scripts, books, and tutorials may rely on this directive being on. If on, for example, one could use $id from the URL http://www.example.com/foo.php?id=42. Whether on or off, $_GET['id'] is available.

For more details on these changes, see the section on predefined variables and links therein.

What's next?

With what you know now you should be able to understand most of the manual and also the various example scripts available in the example archives. You can also find other examples on the php.net websites in the links section: http://www.php.net/links.php.

Kapitola 3. Instalace

General Installation Considerations

Before installing first, you need to know what do you want to use PHP for. There are three main fields you can use PHP, as described in the What can PHP do? section:

Server-side scripting
Command line scripting
Client-side GUI applications

For the first and most common form, you need three things: PHP itself, a web server and a web browser. You probably already have a web browser, and depending on your operating system setup, you may also have a web server (eg. Apache on Linux or IIS on Windows). You may also rent webspace at a company. This way, you don't need to set up anything on your own, only write your PHP scripts, upload it to the server you rent, and see the results in your browser. You can find a list of hosting companies at http://hosts.php.net/.

While setting up the server and PHP on your own, you have two choices for the method of connecting PHP to the server. For many servers PHP has a direct module interface (also called SAPI). These servers include Apache, Microsoft Internet Information Server, Netscape and iPlanet servers. Many other servers have support for ISAPI, the Microsoft module interface (OmniHTTPd for example). If PHP has no module support for your web server, you can always use it as a CGI processor. This means you set up your server to use the command line executable of PHP (php.exe on Windows) to process all PHP file requests on the server.

If you are also interested to use PHP for command line scripting (eg. write scripts autogenerating some images for you offline, or processing text files depending on some arguments you pass to them), you always need the command line executable. For more information, read the section about writing command line PHP applications. In this case, you need no server and no browser.

With PHP you can also write client side GUI applications using the PHP-GTK extension. This is a completely different approach than writing web pages, as you do not output any HTML, but manage windows and objects within them. For more information about PHP-GTK, please visit the site dedicated to this extension. PHP-GTK is not included in the official PHP distribution.

From now on, this section deals with setting up PHP for web servers on Unix and Windows with server module interfaces and CGI executables.

Downloading PHP, the source code, and binary distributions for Windows can be found at http://www.php.net/. We recommend you to choose a mirror nearest to you for downloading the distributions.

Unix/HP-UX installs

This section contains notes and hints specific to installing PHP on HP-UX systems.

Příklad 3-1. Installation Instructions for HP-UX 10

From: paul_mckay@clearwater-it.co.uk
04-Jan-2001 09:49
(These tips are for PHP 4.0.4 and Apache v1.3.9) 

So you want to install PHP and Apache on a HP-UX 10.20 box? 

1. You need gzip, download a binary distribution from
http://hpux.connect.org.uk/ftp/hpux/Gnu/gzip-1.2.4a/gzip-1.2.4a-sd-10.20.depot.Z
uncompress the file and install using swinstall 

2. You need gcc, download a binary distribution from 
http://gatekeep.cs.utah.edu/ftp/hpux/Gnu/gcc-2.95.2/gcc-2.95.2-sd-10.20.depot.gz 
gunzip this file and install gcc using swinstall. 

3. You need the GNU binutils, you can download a binary distribution from 
http://hpux.connect.org.uk/ftp/hpux/Gnu/binutils-2.9.1/binutils-2.9.1-sd-10.20.depot.gz 
gunzip and install using swinstall. 

4. You now need bison, you can download a binary distribution from 
http://hpux.connect.org.uk/ftp/hpux/Gnu/bison-1.28/bison-1.28-sd-10.20.depot.gz 
install as above. 

5. You now need flex, you need to download the source from one of the
http://www.gnu.org mirrors. It is in the <filename>non-gnu</filename> directory of the ftp site. 
Download the file, gunzip, then tar -xvf it. Go into the newly created flex
directory and do a ./configure, then a make, and then a make install 

If you have errors here, it's probably because gcc etc. are not in your
PATH so add them to your PATH. 

Right, now into the hard stuff. 

6. Download the PHP and apache sources. 

7. gunzip and tar -xvf them. 

We need to hack a couple of files so that they can compile ok. 

8. Firstly the configure file needs to be hacked because it seems to lose
track of the fact that you are a hpux machine, there will be a
better way of doing this but a cheap and cheerful hack is to put 
    lt_target=hpux10.20 
on line 47286 of the configure script. 

9. Next, the Apache GuessOS file needs to be hacked. Under
apache_1.3.9/src/helpers change line 89 from 
    "echo "hp${HPUXMACH}-hpux${HPUXVER}"; exit 0" 
to: 
    "echo "hp${HPUXMACH}-hp-hpux${HPUXVER}"; exit 0" 
    
10. You cannot install PHP as a shared object under HP-UX so you must compile
it as a static, just follow the instructions at the Apache page. 

11. PHP and apache should have compiled OK, but Apache won't start. you need
to create a new user for Apache, eg www, or apache. You then change lines 252
and 253 of the conf/httpd.conf in Apache so that instead of 
    User nobody 
    Group nogroup 
you have something like 
    User www 
    Group sys 

This is because you can't run Apache as nobody under hp-ux. 
Apache and PHP should then work. 

Hope this helps somebody,
Paul Mckay.

Unix/Linux installs

This section contains notes and hints specific to installing PHP on Linux distributions.

Using Packages

Many Linux distributions have some sort of package installation system, such as RPM. This can assist in setting up a standard configuration, but if you need to have a different set of features (such as a secure server, or a different database driver), you may need to build PHP and/or your webserver. If you are unfamiliar with building and compiling your own software, it is worth checking to see whether somebody has already built a packaged version of PHP with the features you need.

Unix/Mac OS X installs

This section contains notes and hints specific to installing PHP on Mac OS X Server.

Using Packages

There are a few pre-packaged and pre-compiled versions of PHP for Mac OS X. This can help in setting up a standard configuration, but if you need to have a different set of features (such as a secure server, or a different database driver), you may need to build PHP and/or your web server yourself. If you are unfamiliar with building and compiling your own software, it's worth checking whether somebody has already built a packaged version of PHP with the features you need.

Compiling for OS X server

There are two slightly different versions of Mac OS X, client and server. The following is for OS X Server.

Příklad 3-2. Mac OS X server install

1. Get the latest distributions of Apache and PHP
2. Untar them, and run the configure program on Apache like so.
    ./configure --exec-prefix=/usr \ 
    --localstatedir=/var \ 
    --mandir=/usr/share/man \ 
    --libexecdir=/System/Library/Apache/Modules \ 
    --iconsdir=/System/Library/Apache/Icons \ 
    --includedir=/System/Library/Frameworks/Apache.framework/Versions/1.3/Headers \ 
    --enable-shared=max \ 
    --enable-module=most \ 
    --target=apache 

4. You may also want to add this line: 
    setenv OPTIM=-O2 
    If you want the compiler to do some optimization. 
    
5. Next, go to the PHP 4 source directory and configure it. 
    ./configure --prefix=/usr \ 
    --sysconfdir=/etc \ 
    --localstatedir=/var \ 
    --mandir=/usr/share/man \ 
    --with-xml \ 
    --with-apache=/src/apache_1.3.12 

    If you have any other additions (MySQL, GD, etc.), be sure to add
    them here. For the --with-apache string, put in the path to your 
    apache source directory, for example "/src/apache_1.3.12". 
6. make
7. make install    
    This will add a directory to your Apache source directory under
    src/modules/php4.
    
8. Now, reconfigure Apache to build in PHP 4.
    ./configure --exec-prefix=/usr \ 
    --localstatedir=/var \ 
    --mandir=/usr/share/man \ 
    --libexecdir=/System/Library/Apache/Modules \ 
    --iconsdir=/System/Library/Apache/Icons \ 
    --includedir=/System/Library/Frameworks/Apache.framework/Versions/1.3/Headers \ 
    --enable-shared=max \ 
    --enable-module=most \ 
    --target=apache \ 
    --activate-module=src/modules/php4/libphp4.a 

    You may get a message telling you that libmodphp4.a is out of date.
    If so, go to the src/modules/php4 directory inside your apache
    source directory and run this command: 

    ranlib libmodphp4.a 

    Then go back to the root of the apache source directory and run the
    above configure command again. That'll bring the link table up to
    date. 

9. make

10. make install

11. copy and rename the php.ini-dist file to your "bin" directory from your
    PHP 4 source directory:
    cp php.ini-dist /usr/local/bin/php.ini 

    or (if your don't have a local directory) 

    cp php.ini-dist /usr/bin/php.ini

Other examples for Mac OS X client and Mac OS X server are available at Stepwise.

Compiling for MacOS X client

Those tips are graciously provided by Marc Liyanage.

The PHP module for the Apache web server included in Mac OS X. This version includes support for the MySQL and PostgreSQL databases.

NOTE: Be careful when you do this, you could screw up your Apache web server!

Do this to install:

1. Open a terminal window
2. Type "wget http://www.diax.ch/users/liyanage/software/macosx/libphp4.so.gz", wait for download to finish
3. Type "gunzip libphp4.so.gz"
4. Type "sudo apxs -i -a -n php4 libphp4.so"

Now type "sudo open -a TextEdit /etc/httpd/httpd.conf" TextEdit will open with the web server configuration file. Locate these two lines towards the end of the file: (Use the Find command)

#AddType application/x-httpd-php .php 
   #AddType application/x-httpd-php-source .phps

Remove the two hash marks (#), then save the file and quit TextEdit.

Finally, type "sudo apachectl graceful" to restart the web server.

PHP should now be up and running. You can test it by dropping a file into your "Sites" folder which is called "test.php". Into that file, write this line: "<?php phpinfo() ?>".

Now open up 127.0.0.1/~your_username/test.php in your web browser. You should see a status table with information about the PHP module.

Unix/OpenBSD installs

This section contains notes and hints specific to installing PHP on OpenBSD.

Using Ports

This is the recommended method of installing PHP on OpenBSD, as it will have the latest patches and security fixes applied to it by the maintainers. To use this method, ensure that you have a recent ports tree. Then simply find out which flavors you wish to install, and issue the make install command. Below is an example of how to do this.

Příklad 3-3. OpenBSD Ports Install Example

$ cd /usr/ports/www/php4
$ make show VARNAME=FLAVORS
 (choose which flavors you want from the list)
$ env FLAVOR="imap gettext ldap mysql gd" make install
$ /usr/local/sbin/php4-enable

Using Packages

There are pre-compiled packages available for your release of OpenBSD. These integrate automatically with the version of Apache installed with the OS. However, since there are a large number of options (called flavors) available for this port, you may find it easier to compile it from source using the ports tree. Read the packages(7) manual page for more information in what packages are available.

Unix/Solaris installs

This section contains notes and hints specific to installing PHP on Solaris systems.

Required software

Solaris installs often lack C compilers and their related tools. The required software is as follows:

gcc (recommended, other C compilers may work)
make
flex
bison
m4
autoconf
automake
perl
gzip
tar

In addition, you will need to install (and possibly compile) any additional software specific to your configuration, such as Oracle or MySQL.

Using Packages

You can simplify the Solaris install process by using pkgadd to install most of your needed components.

Installation on UNIX systems

This section will guide you through the general configuration and installation of PHP on Unix systems. Be sure to investigate any sections specific to your platform or web server before you begin the process.

Prerequisite knowledge and software:

Basic UNIX skills (being able to operate "make" and a C compiler, if compiling)
An ANSI C compiler (if compiling)
flex (for compiling)
bison (for compiling)
A web server
Any module specific components (such as gd, pdf libs, etc.)

There are several ways to install PHP for the Unix platform, either with a compile and configure process, or through various pre-packaged methods. This documentation is mainly focused around the process of compiling and configuring PHP.

The initial PHP setup and configuration process is controlled by the use of the commandline options of the configure script. This page outlines the usage of the most common options, but there are many others to play with. Check out the Complete list of configure options for an exhaustive rundown. There are several ways to install PHP:

As an Apache module
As an fhttpd module
For use with AOLServer, NSAPI, phttpd, Pi3Web, Roxen, thttpd, or Zeus.
As a CGI executable

Apache Module Quick Reference

PHP can be compiled in a number of different ways, but one of the most popular is as an Apache module. The following is a quick installation overview.

Příklad 3-4. Quick Installation Instructions for PHP 4 (Apache Module Version)

1.  gunzip apache_1.3.x.tar.gz
2.  tar xvf apache_1.3.x.tar
3.  gunzip php-x.x.x.tar.gz
4.  tar xvf php-x.x.x.tar
5.  cd apache_1.3.x
6.  ./configure --prefix=/www
7.  cd ../php-x.x.x
8.  ./configure --with-mysql --with-apache=../apache_1.3.x --enable-track-vars
9.  make
10. make install
11. cd ../apache_1.3.x
12. ./configure --activate-module=src/modules/php4/libphp4.a
13. make
14. make install
15. cd ../php-x.x.x
16. cp php.ini-dist /usr/local/lib/php.ini
17. Edit your httpd.conf or srm.conf file and add: 
      AddType application/x-httpd-php .php

18. Use your normal procedure for restarting the Apache server. (You must
    stop and restart the server, not just cause the server to reload by
    use a HUP or USR1 signal.)

Building

When PHP is configured, you are ready to build the CGI executable. The command make should take care of this. If it fails and you can't figure out why, see the Problems section.

Installation on Windows systems

This section applies to Windows 95/98/Me and Windows NT/2000/XP. Do not expect PHP to work on 16 bit platforms such as Windows 3.1. Sometimes we refer to the supported Windows platforms as Win32.

There are two main ways to install PHP for Windows: either manually or by using the InstallShield installer.

If you have Microsoft Visual Studio, you can also build PHP from the original source code.

Once you have PHP installed on your Windows system, you may also want to load various extensions for added functionality.

Windows InstallShield

The Windows PHP installer available from the downloads page at http://www.php.net/, this installs the CGI version of PHP and, for IIS, PWS, and Xitami, configures the web server as well. Also note, that while the InstallShield installer is an easy way to make PHP work, it is restricted in many aspects, as automatic setup of extensions for example is not supported.

Install your selected HTTP server on your system and make sure that it works.

Run the executable installer and follow the instructions provided by the installation wizard. Two types of installation are supported - standard, which provides sensible defaults for all the settings it can, and advanced, which asks questions as it goes along.

The installation wizard gathers enough information to set up the php.ini file and configure the web server to use PHP. For IIS and also PWS on NT Workstation, a list of all the nodes on the server with script map settings is displayed, and you can choose those nodes to which you wish to add the PHP script mappings.

Once the installation has completed the installer will inform you if you need to restart your system, restart the server, or just start using PHP.

Varování

Be aware, that this setup of PHP is not secure. If you would like to have a secure PHP setup, you'd better go on the manual way, and set every option carefully. This automatically working setup gives you an instantly working PHP installation, but it is not meant to be used on online servers.

Manual Installation Steps

This install guide will help you manually install and configure PHP on your Windows webserver. You need to download the zip binary distribution from the downloads page at http://www.php.net/. The original version of this guide was compiled by Bob Silva, and can be found at http://www.umesd.k12.or.us/php/win32install.html.

This guide provides manual installation support for:

Personal Web Server 3 and 4 or newer
Internet Information Server 3 and 4 or newer
Apache 1.3.x
OmniHTTPd 2.0b1 and up
Oreilly Website Pro
Xitami
Netscape Enterprise Server, iPlanet

PHP 4 for Windows comes in two flavours - a CGI executable (php.exe), and several SAPI modules (for example: php4isapi.dll). The latter form is new to PHP 4, and provides significantly improved performance and some new functionality.

Varování

The SAPI modules have been significantly improved in the 4.1 release, however, you may find that you encounter possible server errors or other server modules such as ASP failing, in older systems.

If you choose one of the SAPI modules and use Windows 95, be sure to download the DCOM update from the Microsoft DCOM pages. For the ISAPI module, an ISAPI 4.0 compliant Web server is required (tested on IIS 4.0, PWS 4.0 and IIS 5.0). IIS 3.0 is NOT supported. You should download and install the Windows NT 4.0 Option Pack with IIS 4.0 if you want native PHP support.

The following steps should be performed on all installations before the server specific instructions.

Extract the distribution file to a directory of your choice. c:\php\ is a good start. You probably do not want to use a path in which spaces are included (for example: c:\program files\php is not a good idea). Some web servers will crash if you do.

You need to ensure that the DLLs which PHP uses can be found. The precise DLLs involved depend on which web server you use and whether you want to run PHP as a CGI or as a server module. php4ts.dll is always used. If you are using a server module (e.g. ISAPI or Apache) then you will need the relevant DLL from the sapi folder. If you are using any PHP extension DLLs then you will need those as well. To make sure that the DLLs can be found, you can either copy them to the system directory (e.g. winnt/system32 or windows/system) or you can make sure that they live in the same directory as the main PHP executable or DLL your web server will use (e.g. php.exe, php4apache.dll).

The PHP binary, the SAPI modules, and some extensions rely on external DLLs for execution. Make sure that these DLLs in the distribution exist in a directory that is in the Windows PATH. The best bet to do it is to copy the files below into your system directory, which is typically:

c:\windows\system for Windows 9x/ME

c:\winnt\system32 for Windows NT/2000

c:\windows\system32 for Windows XP

The files to copy are:

php4ts.dll, if it already exists there, overwrite it

The files in your distribution's 'dlls' directory. If you have them already installed on your system, overwrite them only if something doesn't work correctly (Before overwriting them, it is a good idea to make a backup of them, or move them to another folder - just in case something goes wrong).

Download the latest version of the Microsoft Data Access Components (MDAC) for your platform, especially if you use Microsoft Windows 9x/NT4. MDAC is available at http://www.microsoft.com/data/.

Copy your chosen ini file (see below) to your '%WINDOWS%' directory on Windows 9x/Me or to your '%SYSTEMROOT%' directory under Windows NT/2000/XP and rename it to php.ini. Your '%WINDOWS%' or '%SYSTEMROOT%' directory is typically:

c:\windows for Windows 9x/ME/XP

c:\winnt or c:\winnt40 for NT/2000 servers

There are two ini files distributed in the zip file, php.ini-dist and php.ini-optimized. We advise you to use php.ini-optimized, because we optimized the default settings in this file for performance, and security. The best is to study all the ini settings and set every element manually yourself. If you would like to achieve the best security, then this is the way for you, although PHP works fine with these default ini files.
Edit your new php.ini file:
- You will need to change the 'extension_dir' setting to point to your php-install-dir, or where you have placed your php_*.dll files. ex: c:\php\extensions
- If you are using OmniHTTPd, do not follow the next step. Set the 'doc_root' to point to your webservers document_root. For example: c:\apache\htdocs or c:\webroot
- Choose which extensions you would like to load when PHP starts. See the section about Windows extensions, about how to set up one, and what is already built in. Note that on a new installation it is advisable to first get PHP working and tested without any extensions before enabling them in php.ini.
- On PWS and IIS, you can set the browscap.ini to point to: c:\windows\system\inetsrv\browscap.ini on Windows 9x/Me, c:\winnt\system32\inetsrv\browscap.ini on NT/2000, and c:\windows\system32\inetsrv\browscap.ini on XP.
- Note that the mibs directory supplied with the Windows distribution contains support files for SNMP. This directory should be moved to DRIVE:\usr\mibs (DRIVE being the drive where PHP is installed.)
- If you're using NTFS on Windows NT, 2000 or XP, make sure that the user running the webserver has read permissions to your php.ini (e.g. make it readable by Everyone).
For PWS give execution permission to the webroot:
- Start PWS Web Manager
- Edit Properties of the "Home"-Directory
- Select the "execute"-Checkbox

Building from source

Before getting started, it is worthwhile answering the question: "Why is building on Windows so hard?" Two reasons come to mind:

Windows does not (yet) enjoy a large community of developers who are willing to freely share their source. As a direct result, the necessary investment in infrastructure required to support such development hasn't been made. By and large, what is available has been made possible by the porting of necessary utilities from Unix. Don't be surprised if some of this heritage shows through from time to time.
Pretty much all of the instructions that follow are of the "set and forget" variety. So sit back and try follow the instructions below as faithfully as you can.

Preparations

Before you get started, you have a lot to download...

For starters, get the Cygwin toolkit from the closest cygwin mirror site. This will provide you most of the popular GNU utilities used by the build process.
Download the rest of the build tools you will need from the PHP site at http://www.php.net/extra/win32build.zip.
Get the source code for the DNS name resolver used by PHP at http://www.php.net/extra/bindlib_w32.zip. This is a replacement for the resolv.lib library included in win32build.zip.
If you don't already have an unzip utility, you will need one. A free version is available from InfoZip.

Finally, you are going to need the source to PHP 4 itself. You can get the latest development version using anonymous CVS. If you get a snapshot or a source tarball, you not only will have to untar and ungzip it, but you will have to convert the bare linefeeds to crlf's in the *.dsp and *.dsw files before Microsoft Visual C++ will have anything to do with them.

Poznámka: Place the Zend and TSRM directories inside the php4 directory in order for the projects to be found during the build process.

Putting it all together

Follow the instructions for installing the unzip utility of your choosing.
Execute setup.exe and follow the installation instructions. If you choose to install to a path other than c:\cygnus, let the build process know by setting the Cygwin environment variable. On Windows 95/98 setting an environment variable can be done by placing a line in your autoexec.bat. On Windows NT, go to My Computer => Control Panel => System and select the environment tab.

Varování

Make a temporary directory for Cygwin to use, otherwise many commands (particularly bison) will fail. On Windows 95/98, mkdir C:\TMP. For Windows NT, mkdir %SystemDrive%\tmp.

Make a directory and unzip win32build.zip into it.
Launch Microsoft Visual C++, and from the menu select Tools => Options. In the dialog, select the directories tab. Sequentially change the dropdown to Executables, Includes, and Library files, and ensure that cygwin\bin, win32build\include, and win32build\lib are in each list, respectively. (To add an entry, select a blank line at the end of the list and begin typing). Typical entries will look like this:
- c:\cygnus\bin
- c:\php-win32build\include
- c:\php-win32build\lib
Press OK, and exit out of Visual C++.
Make another directory and unzip bindlib_w32.zip into it. Decide whether you want to have debug symbols available (bindlib - Win32 Debug) or not (bindlib - Win32 Release). Build the appropriate configuration:
- For GUI users, launch VC++, and then select File => Open Workspace and select bindlib. Then select Build=>Set Active Configuration and select the desired configuration. Finally select Build=>Rebuild All.
- For command line users, make sure that you either have the C++ environment variables registered, or have run vcvars.bat, and then execute one of the following:
  - msdev bindlib.dsp /MAKE "bindlib - Win32 Debug"
  - msdev bindlib.dsp /MAKE "bindlib - Win32 Release"
- At this point, you should have a usable resolv.lib in either your Debug or Release subdirectories. Copy this file into your win32build\lib directory over the file by the same name found in there.

Compiling

The best way to get started is to build the standalone/CGI version.

For GUI users, launch VC++, and then select File => Open Workspace and select php4ts. Then select Build=>Set Active Configuration and select the desired configuration. Finally select Build=>Rebuild All.
For command line users, make sure that you either have the C++ environment variables registered, or have run vcvars.bat, and then execute one of the following:
- msdev php4ts.dsp /MAKE "php4ts - Win32 Debug_TS"
- msdev php4ts.dsp /MAKE "php4ts - Win32 Release_TS"
- At this point, you should have a usable php.exe in either your Debug_TS or Release_TS subdirectories.

Repeat the above steps with php4isapi.dsp (which can be found in sapi\isapi) in order to build the code necessary for integrating PHP with Microsoft IIS.

Installation of Windows extensions

After installing PHP and a webserver on Windows, you will probably want to install some extensions for added functionality. The following table describes some of the extensions available. You can choose which extensions you would like to load when PHP starts by uncommenting the: 'extension=php_*.dll' lines in php.ini. You can also load a module dynamically in your script using dl().

The DLLs for PHP extensions are prefixed with 'php_' in PHP 4 (and 'php3_' in PHP 3). This prevents confusion between PHP extensions and their supporting libraries.

Poznámka: In PHP 4.0.6 BCMath, Calendar, COM, FTP, MySQL, ODBC, PCRE, Session, WDDX and XML support is built in. You don't need to load any additional extensions in order to use these functions. See your distributions README.txt or install.txt for a list of built in modules.

Poznámka: Some of these extensions need extra DLLs to work. Couple of them can be found in the distribution package, in the 'dlls' folder but some, for example Oracle (php_oci8.dll) require DLLs which are not bundled with the distribution package.

Copy the bundled DLLs from 'DLLs' folder to your Windows PATH, safe places are:

c:\windows\system for Windows 9x/Me

c:\winnt\system32 for Windows NT/2000

c:\windows\system32 for Windows XP

If you have them already installed on your system, overwrite them only if something doesn't work correctly (Before overwriting them, it is a good idea to make a backup of them, or move them to another folder - just in case something goes wrong).

Tabulka 3-1. PHP Extensions

Extension	Description	Notes
php_bz2.dll	bzip2 compression functions	None
php_calendar.dll	Calendar conversion functions	Built in since PHP 4.0.3
php_cpdf.dll	ClibPDF functions	None
php_crack.dll	Crack functions	None
php3_crypt.dll	Crypt functions	unknown
php_ctype.dll	ctype family functions	None
php_curl.dll	CURL, Client URL library functions	Requires: libeay32.dll, ssleay32.dll (bundled)
php_cybercash.dll	Cybercash payment functions	None
php_db.dll	DBM functions	Deprecated. Use DBA instead (php_dba.dll)
php_dba.dll	DBA: DataBase (dbm-style) Abstraction layer functions	None
php_dbase.dll	dBase functions	None
php3_dbm.dll	Berkeley DB2 library	unknown
php_domxml.dll	DOM XML functions	Requires: libxml2.dll (bundled)
php_dotnet.dll	.NET functions	None
php_exif.dll	Read EXIF headers from JPEG	None
php_fbsql.dll	FrontBase functions	None
php_fdf.dll	FDF: Forms Data Format functions.	Requires: fdftk.dll (bundled)
php_filepro.dll	filePro functions	Read-only access
php_ftp.dll	FTP functions	Built-in since PHP 4.0.3
php_gd.dll	GD library image functions	None
php_gettext.dll	Gettext functions	Requires: gnu_gettext.dll (bundled)
php_hyperwave.dll	HyperWave functions	None
php_iconv.dll	ICONV characterset conversion	Requires: iconv-1.3.dll (bundled)
php_ifx.dll	Informix functions	Requires: Informix libraries
php_iisfunc.dll	IIS management functions	None
php_imap.dll	IMAP POP3 and NNTP functions	PHP 3: php3_imap4r1.dll
php_ingres.dll	Ingres II functions	Requires: Ingres II libraries
php_interbase.dll	InterBase functions	Requires: gds32.dll (bundled)
php_java.dll	Java extension	Requires: jvm.dll (bundled)
php_ldap.dll	LDAP functions	Requires: libsasl.dll (bundled)
php_mhash.dll	Mhash Functions	None
php_ming.dll	Ming functions for Flash	None
php_msql.dll	mSQL functions	Requires: msql.dll (bundled)
php3_msql1.dll	mSQL 1 client	unknown
php3_msql2.dll	mSQL 2 client	unknown
php_mssql.dll	MSSQL functions	Requires: ntwdblib.dll (bundled)
php3_mysql.dll	MySQL functions	Built-in in PHP 4
php3_nsmail.dll	Netscape mail functions	unknown
php3_oci73.dll	Oracle functions	unknown
php_oci8.dll	Oracle 8 functions	Requires: Oracle 8 client libraries
php_openssl.dll	OpenSSL functions	Requires: libeay32.dll (bundled)
php_oracle.dll	Oracle functions	Requires: Oracle 7 client libraries
php_pdf.dll	PDF functions	None
php_pgsql.dll	PostgreSQL functions	None
php_printer.dll	Printer functions	None
php_xslt.dll	XSLT functions	Requires: sablot.dll (bundled)
php_snmp.dll	SNMP get and walk functions	NT only!
php_sybase_ct.dll	Sybase functions	Requires: Sybase client libraries
php_yaz.dll	YAZ functions	None
php_zlib.dll	ZLib compression functions	None

Servers-CGI/Commandline

The default is to build PHP as a CGI program. This creates a commandline interpreter, which can be used for CGI processing, or for non-web-related PHP scripting. If you are running a web server PHP has module support for, you should generally go for that solution for performance reasons. However, the CGI version enables Apache users to run different PHP-enabled pages under different user-ids. Please make sure you read through the Security chapter if you are going to run PHP as a CGI.

Testing

If you have built PHP as a CGI program, you may test your build by typing make test. It is always a good idea to test your build. This way you may catch a problem with PHP on your platform early instead of having to struggle with it later.

Benchmarking

If you have built PHP 3 as a CGI program, you may benchmark your build by typing make bench. Note that if Safe Mode is on by default, the benchmark may not be able to finish if it takes longer then the 30 seconds allowed. This is because the set_time_limit() can not be used in safe mode. Use the max_execution_time configuration setting to control this time for your own scripts. make bench ignores the configuration file.

Poznámka: make bench is only available for PHP 3.

Using Variables

Some server supplied enviroment variables are not defined in the current CGI/1.1 specification. Only the following variables are defined there; everything else should be treated as 'vendor extensions': AUTH_TYPE, CONTENT_LENGTH, CONTENT_TYPE, GATEWAY_INTERFACE, PATH_INFO, PATH_TRANSLATED, QUERY_STRING, REMOTE_ADDR, REMOTE_HOST, REMOTE_IDENT, REMOTE_USER, REQUEST_METHOD, SCRIPT_NAME, SERVER_NAME, SERVER_PORT, SERVER_PROTOCOL and SERVER_SOFTWARE

Servers-Apache

This section contains notes and hints specific to Apache installs of PHP, both for Unix and Windows versions.

Details of installing PHP with Apache on Unix

You can select arguments to add to the configure on line 8 below from the Complete list of configure options. The version numbers have been omitted here, to ensure the instructions are not incorrect. You will need to replace the 'xxx' here with the correct values from your files.

Příklad 3-5. Installation Instructions (Apache Shared Module Version) for PHP 4

1.  gunzip apache_xxx.tar.gz
2.  tar -xvf apache_xxx.tar
3.  gunzip php-xxx.tar.gz
4.  tar -xvf php-xxx.tar
5.  cd apache_xxx
6.  ./configure --prefix=/www --enable-module=so
7.  make
8.  make install
9.  cd ../php-xxx
10. ./configure --with-mysql --with-apxs=/www/bin/apxs
11. make
12. make install

  If you decide to change your configure options after installation
  you only need to repeat the last three steps. You only need to 
  restart apache for the new module to take effect. A recompile of
  Apache is not needed.

11. cp php.ini-dist /usr/local/lib/php.ini

  You can edit your .ini file to set PHP options.  If
  you prefer this file in another location, use
  --with-config-file-path=/path in step 8.

12. Edit your httpd.conf or srm.conf file and check that these lines are
    present and not commented out:
  
   AddType application/x-httpd-php .php

   LoadModule php4_module        libexec/libphp4.so
 
  You can choose any extension you wish here.  .php is simply the one
  we suggest. You can even include .html, and .php3 can be added for 
  backwards compatibility.
 
  The path on the right hand side of the LoadModule statement must point
  to the path of the PHP module on your system. The above statement is 
  correct for the steps shown above.


13. Use your normal procedure for starting the Apache server. (You must
    stop and restart the server, not just cause the server to reload by
    use a HUP or USR1 signal.)

Depending on your Apache install and Unix variant, there are many possible ways to stop and restart the server. Below are some typical lines used in restarting the server, for different apache/unix installations. You should replace /path/to/ with the path to these applications on your systems.

1. Several Linux and SysV variants:
/etc/rc.d/init.d/httpd restart

2. Using apachectl scripts:
/path/to/apachectl stop
/path/to/apachectl start

3. httpdctl and httpsdctl (Using OpenSSL), similar to apachectl:
/path/to/httpsdctl stop
/path/to/httpsdctl start

4. Using mod_ssl, or another SSL server, you may want to manually
stop and start:
/path/to/apachectl stop
/path/to/apachectl startssl

The locations of the apachectl and http(s)dctl binaries often vary. If your system has locate or whereis or which commands, these can assist you in finding your server control programs.

Different examples of compiling PHP for apache are as follows:

./configure --with-apxs --with-pgsql

This will create a libphp4.so shared library that is loaded into Apache using a LoadModule line in Apache's httpd.conf file. The PostgreSQL support is embedded into this libphp4.so library.

./configure --with-apxs --with-pgsql=shared

This will create a libphp4.so shared library for Apache, but it will also create a pgsql.so shared library that is loaded into PHP either by using the extension directive in php.ini file or by loading it explicitly in a script using the dl() function.

./configure --with-apache=/path/to/apache_source --with-pgsql

This will create a libmodphp4.a library, a mod_php4.c and some accompanying files and copy this into the src/modules/php4 directory in the Apache source tree. Then you compile Apache using --activate-module=src/modules/php4/libphp4.a and the Apache build system will create libphp4.a and link it statically into the httpd binary. The PostgreSQL support is included directly into this httpd binary, so the final result here is a single httpd binary that includes all of Apache and all of PHP.

./configure --with-apache=/path/to/apache_source --with-pgsql=shared

Same as before, except instead of including PostgreSQL support directly into the final httpd you will get a pgsql.so shared library that you can load into PHP from either the php.ini file or directly using dl().

When choosing to build PHP in different ways, you should consider the advantages and drawbacks of each method. Building as a shared object will mean that you can compile apache separately, and don't have to recompile everything as you add to, or change, PHP. Building PHP into apache (static method) means that PHP will load and run faster. For more information, see the Apache webpage on DSO support.

Poznámka: Apache's default http.conf currently ships with a section that looks like this:
User nobody
Group "#-1"
Unless you change that to "Group nogroup" or something like that ("Group daemon" is also very common) PHP will not be able to open files.

Poznámka: Make sure you specify the installed version of apxs when using --with-apxs=/path/to/apxs. You must NOT use the apxs version that is in the apache sources but the one that is actually installed on your system.

Installing PHP on Windows with Apache 1.3.x

There are two ways to set up PHP to work with Apache 1.3.x on Windows. One is to use the CGI binary (php.exe), the other is to use the Apache module DLL. In either case you need to stop the Apache server, and edit your srm.conf or httpd.conf to configure Apache to work with PHP.

It is worth noting here that now the SAPI module has been made more stable under windows, we recommend it's use above the CGI binary, since it is more transparent and secure.

Although there can be a few variations of configuring PHP under Apache, these are simple enough to be used by the newcomer. Please consult the Apache Docs for further configuration directives.

If you unziped the PHP package to c:\php\ as described in the Manual Installation Steps section, you need to insert these lines to your Apache configuration file to set up the CGI binary:

ScriptAlias /php/ "c:/php/"
AddType application/x-httpd-php .php .phtml
Action application/x-httpd-php "/php/php.exe"

Note that the second line in the list above can be found in the actual versions of httpd.conf, but it is commented out. Remember also to substitute the c:/php/ for your actual path to PHP.

Varování

By using the CGI setup, your server is open to several possible attacks. Please read our CGI security section to learn how to defend yourself from attacks.

If you would like to use PHP as a module in Apache, be sure to move php4ts.dll to the windows/system (for Windows 9x/Me) or winnt/system32 (for Windows NT/2000/XP) directory, overwriting any older file. Then you should add the following two lines to you Apache conf file:

LoadModule php4_module c:/php/sapi/php4apache.dll
AddType application/x-httpd-php .php .phtml

After changing the configuration file, remember to restart the server, for example, NET STOP APACHE followed by NET START APACHE, if you run Apache as a Windows Service, or use your regular shortcuts.

Poznámka: You may find after using the windows installer for Apache that you need to define the AddModule directive for mod_php4.c in the configuration file (httpd.conf). This is done by adding AddModule mod_php4.c to the AddModule list, near the beginning of the configuration file. This is especially important if the ClearModuleList directive is defined. Failure to do this may mean PHP will not be registered as an Apache module.

There are 2 ways you can use the source code highlighting feature, however their ability to work depends on your installation. If you have configured Apache to use PHP as an ISAPI module, then by adding the following line to your configuration file you can use this feature: AddType application/x-httpd-php-source .phps

If you chose to configure Apache to use PHP as a CGI binary, you will need to use the show_source() function. To do this simply create a PHP script file and add this code: <?php show_source ("original_php_script.php"); ?>. Substitute original_php_script.php with the name of the file you wish to show the source of.

Poznámka: On Win-Apache all backslashes in a path statement such as "c:\directory\file.ext", must be converted to forward slashes, as "c:/directory/file.ext".

Servers-Caudium

PHP 4 can be built as a Pike module for the Caudium webserver. Note that this is not supported with PHP 3. Follow the simple instructions below to install PHP 4 for Caudium.

Příklad 3-6. Caudium Installation Instructions

1.  Make sure you have Caudium installed prior to attempting to
    install PHP 4. For PHP 4 to work correctly, you will need Pike
    7.0.268 or newer. For the sake of this example we assume that
    Caudium is installed in /opt/caudium/server/.
2.  Change directory to php-x.y.z (where x.y.z is the version number).
3.  ./configure --with-caudium=/opt/caudium/server
4.  make
5.  make install
6.  Restart Caudium if it's currently running.
7.  Log into the graphical configuration interface and go to the
    virtual server where you want to add PHP 4 support.
8.  Click Add Module and locate and then add the PHP 4 Script Support module.
9.  If the documentation says that the 'PHP 4 interpreter isn't
    available', make sure that you restarted the server. If you did
    check /opt/caudium/logs/debug/default.1 for any errors related to
    <filename>PHP4.so</filename>. Also make sure that 
    <filename>caudium/server/lib/[pike-version]/PHP4.so</filename>
    is present.
10. Configure the PHP Script Support module if needed.

You can of course compile your Caudium module with support for the various extensions available in PHP 4. See the complete list of configure options for an exhaustive rundown.

Poznámka: When compiling PHP 4 with MySQL support you must make sure that the normal MySQL client code is used. Otherwise there might be conflicts if your Pike already has MySQL support. You do this by specifying a MySQL install directory the --with-mysql option.

Servers-fhttpd

To build PHP as an fhttpd module, answer "yes" to "Build as an fhttpd module?" (the --with-fhttpd=DIR option to configure) and specify the fhttpd source base directory. The default directory is /usr/local/src/fhttpd. If you are running fhttpd, building PHP as a module will give better performance, more control and remote execution capability.

Servers-IIS/PWS

This section contains notes and hints specific to IIS (Microsoft Internet Information Server). Installing PHP for PWS/IIS 3, PWS 4 or newer and IIS 4 or newer versions.

Windows and PWS/IIS 3

The recommended method for configuring these servers is to use the REG file included with the distribution (pws-php4cgi.reg). You may want to edit this file and make sure the extensions and PHP install directories match your configuration. Or you can follow the steps below to do it manually.

Varování

These steps involve working directly with the Windows registry. One error here can leave your system in an unstable state. We highly recommend that you back up your registry first. The PHP Development team will not be held responsible if you damage your registry.

Run Regedit.
Navigate to: HKEY_LOCAL_MACHINE /System /CurrentControlSet /Services /W3Svc /Parameters /ScriptMap.
On the edit menu select: New->String Value.
Type in the extension you wish to use for your php scripts. For example .php
Double click on the new string value and enter the path to php.exe in the value data field. ex: c:\php\php.exe.
Repeat these steps for each extension you wish to associate with PHP scripts.

The following steps do not affect the web server installation and only apply if you want your php scripts to be executed when they are run from the command line (ex. run c:\myscripts\test.php) or by double clicking on them in a directory viewer window. You may wish to skip these steps as you might prefer the PHP files to load into a text editor when you double click on them.

Navigate to: HKEY_CLASSES_ROOT
On the edit menu select: New->Key.
Name the key to the extension you setup in the previous section. ex: .php
Highlight the new key and in the right side pane, double click the "default value" and enter phpfile.
Repeat the last step for each extension you set up in the previous section.
Now create another New->Key under HKEY_CLASSES_ROOT and name it phpfile.
Highlight the new key phpfile and in the right side pane, double click the "default value" and enter PHP Script.
Right click on the phpfile key and select New->Key, name it Shell.
Right click on the Shell key and select New->Key, name it open.
Right click on the open key and select New->Key, name it command.
Highlight the new key command and in the right side pane, double click the "default value" and enter the path to php.exe. ex: c:\php\php.exe -q %1. (don't forget the %1).
Exit Regedit.
If using PWS on Windows, reboot to reload the registry.

PWS and IIS 3 users now have a fully operational system. IIS 3 users can use a nifty tool from Steven Genusa to configure their script maps.

Windows and PWS 4 or newer

When installing PHP on Windows with PWS 4 or newer version, you have two options. One to set up the PHP CGI binary, the other is to use the ISAPI module DLL.

If you choose the CGI binary, do the following:

Edit the enclosed pws-php4cgi.reg file (look into the SAPI dir) to reflect the location of your php.exe. Forward slashes should be escaped, for example: [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\w3svc\parameters\Script Map] ".php"="c:\\php\\php.exe"
In the PWS Manager, right click on a given directory you want to add PHP support to, and select Properties. Check the 'Execute' checkbox, and confirm.

If you choose the ISAPI module, do the following:

Edit the enclosed pws-php4isapi.reg file (look into the SAPI dir) to reflect the location of your php4isapi.dll. Forward slashes should be escaped, for example: [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\w3svc\parameters\Script Map] ".php"="c:\\php\\sapi\\php4isapi.dll"
In the PWS Manager, right click on a given directory you want to add PHP support to, and select Properties. Check the 'Execute' checkbox, and confirm.

Windows NT/2000/XP and IIS 4 or newer

To install PHP on an NT/2000/XP Server running IIS 4 or newer, follow these instructions. You have two options to set up PHP, using the CGI binary (php.exe) or with the ISAPI module.

In either case, you need to start the Microsoft Management Console (may appear as 'Internet Services Manager', either in your Windows NT 4.0 Option Pack branch or the Control Panel=>Administrative Tools under Windows 2000/XP). Then right click on your Web server node (this will most probably appear as 'Default Web Server'), and select 'Properties'.

If you want to use the CGI binary, do the following:

Under 'Home Directory', 'Virtual Directory', or 'Directory', click on the 'Configuration' button, and then enter the App Mappings tab.
Click Add, and in the Executable box, type: c:\php\php.exe (assuming that you have unziped PHP in c:\php\).
In the Extension box, type the file name extension you want associated with PHP scripts. Leave 'Method exclusions' blank, and check the Script engine checkbox. You may also like to check the 'check that file exists' box - for a small performance penalty, IIS (or PWS) will check that the script file exists and sort out authentication before firing up php. This means that you will get sensible 404 style error messages instead of cgi errors complaining that php did not output any data.

You must start over from the previous step for each extension you want associated with PHP scripts. .php and .phtml are common, although .php3 may be required for legacy applications.
Set up the appropriate security. (This is done in Internet Service Manager), and if your NT Server uses NTFS file system, add execute rights for I_USR_ to the directory that contains php.exe.

To use the ISAPI module, do the following:

If you don't want to perform HTTP Authentication using PHP, you can (and should) skip this step. Under ISAPI Filters, add a new ISAPI filter. Use PHP as the filter name, and supply a path to the php4isapi.dll.
Under 'Home Directory', click on the 'Configuration' button. Add a new entry to the Application Mappings. Use the path to the php4isapi.dll as the Executable, supply .php as the extension, leave Method exclusions blank, and check the Script engine checkbox.
Stop IIS completely (NET STOP iisadmin)
Start IIS again (NET START w3svc)

Servers-Netscape and iPlanet

This section contains notes and hints specific to Netscape and iPlanet installs of PHP, both for Sun Solaris and Windows versions.

You can find more information about setting up PHP for the Netscape Enterprise Server here: http://benoit.noss.free.fr/php/install-php4.html

Installing PHP with Netscape on Sun Solaris

To build PHP with NES or iPlanet web servers, enter the proper install directory for the --with-nsapi = DIR option. The default directory is usually /opt/netscape/suitespot/. Please also read /php-xxx-version/sapi/nsapi/nsapi-readme.txt.

Příklad 3-7. Installation Example for Netscape Enterprise on Solaris

Instructions for Sun Solaris 2.6 with Netscape Enterprise Server 3.6 From: bhager@invacare.com 1. Install the following packages from www.sunfreeware.com or another download site: flex-2_5_4a-sol26-sparc-local gcc-2_95_2-sol26-sparc-local gzip-1.2.4-sol26-sparc-local perl-5_005_03-sol26-sparc-local bison-1_25-sol26-sparc-local make-3_76_1-sol26-sparc-local m4-1_4-sol26-sparc-local autoconf-2.13 automake-1.4 mysql-3.23.24-beta (if you want mysql support) tar-1.13 (GNU tar) 2. Make sure your path includes the proper directories PATH=.:/usr/local/bin:/usr/sbin:/usr/bin:/usr/ccs/bin export PATH 3. gunzip php-x.x.x.tar.gz (if you have a .gz dist, otherwise go to 4) 4. tar xvf php-x.x.x.tar 5. cd ../php-x.x.x 6. For the following step, make sure /opt/netscape/suitespot/ is where your netscape server is installed. Otherwise, change to correct path: /configure --with-mysql=/usr/local/mysql --with-nsapi=/opt/netscape/suitespot/ --enable-track-vars --enable-libgcc 7. make 8. make install
After performing the base install and reading the appropriate readme file, you may need to performs some additional configuration steps.

Firstly you may need to add some paths to the LD_LIBRARY_PATH environment for Netscape to find all the shared libs. This can best done in the start script for your Netscape server. Windows users can probably skip this step. The start script is often located in: /path/to/server/https-servername/start

You may also need to edit the configuration files that are located in:/path/to/server/https-servername/config/.

Příklad 3-8. Configuration Example for Netscape Enterprise

Configuration Instructions for Netscape Enterprise Server
From: bhager@invacare.com

1. Add the following line to mime.types:
    type=magnus-internal/x-httpd-php exts=php

2. Add the following to obj.conf, shlib will vary depending on
    your OS, for unix it will be something like
    /opt/netscape/suitespot/bin/libphp4.so.

    You should place the following lines after mime types init.
    Init fn="load-modules" funcs="php4_init,php4_close,php4_execute,php4_auth_trans" shlib="/php4/nsapiPHP4.dll"
    Init fn=php4_init errorString="Failed to initialize PHP!"

    <object name="default">
    . 
    . 
    . 
    .#NOTE this next line should happen after all 'ObjectType' and before all 'AddLog' lines 
    Service fn="php4_execute" type="magnus-internal/x-httpd-php" 
    . 
    . 
    </Object>


    <Object name="x-httpd-php"> 
    ObjectType fn="force-type" type="magnus-internal/x-httpd-php" 
    Service fn=php4_execute 
    </Object> 


    Authentication configuration 

    PHP authentication cannot be used with any other authentication. ALL AUTHENTICATION IS 
    PASSED TO YOUR PHP SCRIPT. To configure PHP Authentication for the entire server, add 
    the following line: 

    <Object name="default"> 
    AuthTrans fn=php4_auth_trans 
    . 
    . 
    . 
    . 
    </Object> 

    To use PHP Authentication on a single directory, add the following: 

    <Object ppath="d:\path\to\authenticated\dir\*"> 
    AuthTrans fn=php4_auth_trans 
    </Object>

If you are running Netscape Enterprise 4.x, then you should use the following:

Příklad 3-9. Configuration Example for Netscape Enterprise 4.x

Place these lines after the mime types init, and everything else is similar
to the example configuration above.
From: Graeme Hoose (GraemeHoose@BrightStation.com)

Init fn="load-modules" shlib="/path/to/server4/bin/libphp4.so" funcs="php4_init,php4_close,php4_execute,php4_auth_trans"
Init fn="php4_init" LateInit="yes"

Installing PHP with Netscape on Windows

To Install PHP as CGI (for Netscape Enterprise Server, iPlanet, perhaps Fastrack), do the following:

Copy php4ts.dll to your systemroot (the directory where you installed windows)
Make a file association from the command line. Type the following two lines:
assoc .php=PHPScript ftype PHPScript=c:\php\php.exe %1 %*
In the Netscape Enterprise Administration Server create a dummy shellcgi directory and remove it just after (this step creates 5 important lines in obj.conf and allow the web server to handle shellcgi scripts).
In the Netscape Enterprise Administration Server create a new mime type (Category: type, Content-Type: magnus-internal/shellcgi, File Suffix:php).
Do it for each web server instance you want php to run

More details about setting up PHP as a CGI executable can be found here: http://benoit.noss.free.fr/php/install-php.html

To Install PHP as NSAPI (for Netscape Enterprise Server, iPlanet, perhaps Fastrack, do the following:

Copy php4ts.dll to your systemroot (the directory where you installed windows)
Make a file association from the command line. Type the following two lines:
assoc .php=PHPScript ftype PHPScript=c:\php\php.exe %1 %*
In the Netscape Enterprise Administration Server create a new mime type (Category: type, Content-Type: magnus-internal/x-httpd-php, File Suffix:php).

Stop your web service and edit obj.conf. At the end of the Init section, place these two lines (necessarily after mime type init!):

Init fn="load-modules" funcs="php4_init,php4_close,php4_execute,php4_auth_trans" shlib="c:/php/sapi/php4nsapi.dll" Init fn="php4_init" errorString="Failed to initialise PHP!"

In The < Object name="default" > section, place this line necessarily after all 'ObjectType' and before all 'AddLog' lines:
Service fn="php4_execute" type="magnus-internal/x-httpd-php"

At the end of the file, create a new object called x-httpd-php, by inserting these lines:

<Object name="x-httpd-php"> ObjectType fn="force-type" type="magnus-internal/x-httpd-php" Service fn=php4_execute </Object>

Restart your web service and apply changes
Do it for each web server instance you want PHP to run

More details about setting up PHP as an NSAPI filter can be found here: http://benoit.noss.free.fr/php/install-php4.html

Servers-OmniHTTPd Server

This section contains notes and hints specific to OmniHTTPd.

OmniHTTPd 2.0b1 and up for Windows

You need to complete the following steps to make PHP work with OmniHTTPd. This is a CGI executable setup. SAPI is supported by OmniHTTPd, but some tests have shown that it is not so stable to use PHP as an ISAPI module.

Step 1: Install OmniHTTPd server.
Step 2: Right click on the blue OmniHTTPd icon in the system tray and select Properties
Step 3: Click on Web Server Global Settings
Step 4: On the 'External' tab, enter: virtual = .php | actual = c:\path-to-php-dir\php.exe, and use the Add button.
Step 5: On the Mime tab, enter: virtual = wwwserver/stdcgi | actual = .php, and use the Add button.
Step 6: Click OK

Repeat steps 2 - 6 for each extension you want to associate with PHP.

Poznámka: Some OmniHTTPd packages come with built in PHP support. You can choose at setup time to do a custom setup, and uncheck the PHP component. We recommend you to use the latest PHP binaries. Some OmniHTTPd servers come with PHP 4 beta distributions, so you should choose not to set up the built in support, but install your own. If the server is already on your machine, use the Replace button in Step 4 and 5 to set the new, correct information.

Servers-Oreilly Website Pro

This section contains notes and hints specific to Oreilly Website Pro.

Oreilly Website Pro 2.5 and up for Windows

This list describes how to set up the PHP CGI binary or the ISAPI module to work with Oreilly Website Pro on Windows.

Edit the Server Properties and select the tab "Mapping".
From the List select "Associations" and enter the desired extension (.php) and the path to the CGI exe (ex. c:\php\php.exe) or the ISAPI DLL file (ex. c:\php\sapi\php4isapi.dll).
Select "Content Types" add the same extension (.php) and enter the content type. If you choose the CGI executable file, enter 'wwwserver/shellcgi', if you choose the ISAPI module, enter 'wwwserver/isapi' (both without quotes).

Servers-Xitami

This section contains notes and hints specific to Xitami.

Xitami for Windows

This list describes how to set up the PHP CGI binary to work with Xitami on Windows.

Make sure the webserver is running, and point your browser to xitamis admin console (usually http://127.0.0.1/admin), and click on Configuration.
Navigate to the Filters, and put the extension which PHP should parse (i.e. .php) into the field File extensions (.xxx).
In Filter command or script put the path and name of your php executable i.e. c:\php\php.exe.
Press the 'Save' icon.
Restart the server to reflect changes.

Servers-Other web servers

PHP can be built to support a large number of web servers. Please see Server-related options for a full list of server-related configure options. The PHP CGI binaries are compatible with almost all webservers supporting the CGI standard.

Problems?

Read the FAQ

Some problems are more common than others. The most common ones are listed in the PHP FAQ, part of this manual.

Bug reports

If you think you have found a bug in PHP, please report it. The PHP developers probably don't know about it, and unless you report it, chances are it won't be fixed. You can report bugs using the bug-tracking system at http://bugs.php.net/. Please do not send bug reports in mailing list or personal letters. The bug system is also suitable to submit feature requests.

Read the How to report a bug document before submitting any bug reports!

Complete list of configure options

Poznámka: These are only used at compile time. If you want to alter PHP's runtime configuration, please see the chapter on Configuration.

The following is a complete list of options supported by PHP 4 configure scripts (as of 4.1.0), used when compiling in Unix-like environments. Some are available in PHP 3, some in PHP 4, and some in both. This is not noted yet.

Configure Options in PHP 4

Poznámka: These options are only used in PHP 4 as of PHP 4.1.0. Some are available in older versions of PHP 4, some even in PHP 3, some only in PHP 4.1.0. If you want to compile an older version, some options will probably not be available.

Database options

--with-db: Include old xDBM support (deprecated).
--enable-dba=shared: Build DBA as a shared module.
--with-gdbm[=DIR]: Include GDBM support.
--with-ndbm[=DIR]: Include NDBM support.
--with-db2[=DIR]: Include Berkeley DB2 support.
--with-db3[=DIR]: Include Berkeley DB3 support.
--with-dbm[=DIR]: Include DBM support.
--with-cdb[=DIR]: Include CDB support.
--enable-dbase: Enable the bundled dbase library.
--with-dbplus: Include dbplus support.
--enable-dbx: Enable dbx.
--with-fbsql[=DIR]: Include FrontBase support. DIR is the FrontBase base directory.
--enable-filepro: Enable the bundled read-only filePro support.
--with-fribidi[=DIR]: Include fribidi support (requires FriBidi >=0.1.12). DIR is the fribidi installation directory - default /usr/local/.
--with-informix[=DIR]: Include Informix support. DIR is the Informix base install directory, defaults to nothing.
--with-ingres[=DIR]: Include Ingres II support. DIR is the Ingres base directory (default /II/ingres).
--with-interbase[=DIR]: Include InterBase support. DIR is the InterBase base install directory, defaults to /usr/interbase.
--with-msql[=DIR]: Include mSQL support. DIR is the mSQL base install directory, defaults to /usr/local/Hughes.
--with-mysql[=DIR]: Include MySQL support. DIR is the MySQL base directory. If unspecified, the bundled MySQL library will be used.
--with-oci8[=DIR]: Include Oracle-oci8 support. Default DIR is ORACLE_HOME.
--with-adabas[=DIR]: Include Adabas D support. DIR is the Adabas base install directory, defaults to /usr/local.
--with-sapdb[=DIR]: Include SAP DB support. DIR is SAP DB base install directory, defaults to /usr/local.
--with-solid[=DIR]: Include Solid support. DIR is the Solid base install directory, defaults to /usr/local/solid.
--with-ibm-db2[=DIR]: Include IBM DB2 support. DIR is the DB2 base install directory, defaults to /home/db2inst1/sqllib.
--with-empress[=DIR]: Include Empress support. DIR is the Empress base install directory, defaults to $EMPRESSPATH. From PHP4, this option only supports Empress Version 8.60 and above.
--with-empress-bcs[=DIR]: Include Empress Local Access support. DIR is the Empress base install directory, defaults to $EMPRESSPATH. From PHP4, this option only supports Empress Version 8.60 and above.
--with-birdstep[=DIR]: Include Birdstep support. DIR is the Birdstep base install directory, defaults to /usr/local/birdstep.
--with-custom-odbc[=DIR]: Include a user defined ODBC support. The DIR is ODBC install base directory, which defaults to /usr/local. Make sure to define CUSTOM_ODBC_LIBS and have some odbc.h in your include dirs. E.g., you should define following for Sybase SQL Anywhere 5.5.00 on QNX, prior to run configure script: CPPFLAGS="-DODBC_QNX -DSQLANY_BUG" LDFLAGS=-lunix CUSTOM_ODBC_LIBS="-ldblib -lodbc".
--with-iodbc[=DIR]: Include iODBC support. DIR is the iODBC base install directory, defaults to /usr/local.
--with-esoob[=DIR]: Include Easysoft OOB support. DIR is the OOB base install directory, defaults to /usr/local/easysoft/oob/client.
--with-unixODBC[=DIR]: Include unixODBC support. DIR is the unixODBC base install directory, defaults to /usr/local.
--with-openlink[=DIR]: Include OpenLink ODBC support. DIR is the OpenLink base install directory, defaults to /usr/local. This is the same as iODBC.
--with-dbmaker[=DIR]: Include DBMaker support. DIR is the DBMaker base install directory, defaults to where the latest version of DBMaker is installed (such as /home/dbmaker/3.6).
--with-oracle[=DIR]: Include Oracle-oci7 support. Default DIR is ORACLE_HOME.
--with-ovrimos[=DIR]: Include Ovrimos SQL Server support. DIR is the Ovrimos' libsqlcli install directory.
--with-pgsql[=DIR]: Include PostgreSQL support. DIR is the PostgreSQL base install directory, defaults to /usr/local/pgsql. Set DIR to shared to build as a dl, or shared,DIR to build as a dl and still specify DIR.
--with-sybase[=DIR]: Include Sybase-DB support. DIR is the Sybase home directory, defaults to /home/sybase.
--with-sybase-ct[=DIR]: Include Sybase-CT support. DIR is the Sybase home directory. Defaults to /home/sybase.
--disable-unified-odbc: Disable unified ODBC support. Only applicable if iODBC, Adabas, Solid, Velocis or a custom ODBC interface is enabled. PHP 3 only!

Graphics options

--with-gd[=DIR]: Include GD support (DIR is GD's install dir). Set DIR to shared to build as a dl, or shared,DIR to build as a dl and still specify DIR.
--enable-gd-native-ttf: GD: Enable TrueType string function in gd.
--with-jpeg-dir=DIR: GD: Set the path to libjpeg install prefix.
--with-png-dir=DIR: GD: Set the path to libpng install prefix.
--with-xpm-dir=DIR: GD: Set the path to libXpm install prefix.
--with-freetype-dir=DIR: GD: Set the path to freetype2 install prefix.
--with-ttf[=DIR]: GD: Include FreeType 1.x support.
--with-t1lib[=DIR]: GD: Include T1lib support.
--with-cpdflib[=DIR]: Include cpdflib support (requires cpdflib >= 2). DIR is the cpdfllib install directory, defaults to /usr.
--with-jpeg-dir[=DIR]: jpeg dir for cpdflib 2.x.
--with-tiff-dir[=DIR]: tiff dir for cpdflib 2.x.
--with-pdflib[=DIR]: Include PDFlib support. DIR is the pdflib base install directory, defaults to /usr/local. Set DIR to shared to build as dl, or shared,DIR to build as dl and still specify DIR.
--with-jpeg-dir[=DIR]: PDFLIB: define libjpeg install directory.
--with-png-dir[=DIR]: PDFLIB: define libpng install directory.
--with-tiff-dir[=DIR]: PDFLIB: define libtiff install directory.
--with-swf[=DIR]: Include swf support.
--without-gd: Disable GD support. PHP 3 only!
--with-imagick: Include ImageMagick support. DIR is the install directory, and if left out, PHP will try to find it on its own. [experimental]. PHP 3 only!
--with-ming[=DIR]: Include ming support.

Misc options

--enable-force-cgi-redirect: Enable the security check for internal server redirects. You should use this if you are running the CGI version with Apache.
--enable-discard-path: If this is enabled, the PHP CGI binary can safely be placed outside of the web tree and people will not be able to circumvent .htaccess security.
--with-fastcgi=SRCDIR: Build PHP as FastCGI application.
--enable-debug: Compile with debugging symbols.
--with-layout=TYPE: Sets how installed files will be laid out. Type is one of PHP (default) or GNU.
--with-pear=DIR: Install PEAR in DIR (default PREFIX/lib/php).
--without-pear: Do not install PEAR.
--with-openssl[=DIR]: Include OpenSSL support (requires OpenSSL >= 0.9.5).
--enable-sigchild: Enable PHP's own SIGCHLD handler.
--disable-rpath: Disable passing additional runtime library search paths.
--enable-libgcc: Enable explicitly linking against libgcc.
--enable-dmalloc: Enable dmalloc.
--enable-php-streams: Include experimental php streams. Do not use unless you are testing the code!
--with-zlib-dir=<DIR>: Define the location of zlib install directory.
--with-zlib[=DIR]: Include zlib support (requires zlib >= 1.0.9). DIR is the zlib install directory.
--with-aspell[=DIR]: Include ASPELL support.
--enable-bcmath: Enable bc style precision math functions.
--with-bz2[=DIR]: Include BZip2 support.
--enable-calendar: Enable support for calendar conversion.
--with-ccvs[=DIR]: Include CCVS support.
--with-crack[=DIR]: Include crack support.
--enable-ctype: Enable ctype support.
--with-curl[=DIR]: Include CURL support.
--with-cybercash[=DIR]: Include CyberCash support. DIR is the CyberCash MCK install directory.
--with-cybermut[=DIR]: Include CyberMut (French Credit Mutuel telepaiement).
--with-cyrus: Include cyrus IMAP support.
--enable-exif: Enable exif support.
--with-fdftk[=DIR]: Include fdftk support.
--enable-ftp: Enable FTP support.
--with-gettext[=DIR]: Include GNU gettext support. DIR is the gettext install directory, defaults to /usr/local.
--with-gmp: Include gmp support.
--with-hyperwave: Include Hyperwave support.
--with-icap[=DIR]: Include ICAP support.
--with-iconv[=DIR]: Include iconv support.
--with-imap[=DIR]: Include IMAP support. DIR is the c-client install prefix.
--with-kerberos[=DIR]: IMAP: Include Kerberos support. DIR is the Kerberos install dir.
--with-imap-ssl[=DIR]: IMAP: Include SSL support. DIR is the OpenSSL install dir.
--with-ircg-config: Path to the ircg-config script.
--with-ircg: Include ircg support.
--with-java[=DIR]: Include Java support. DIR is the base install directory for the JDK. This extension can only be built as a shared dl.
--with-ldap[=DIR]: Include LDAP support. DIR is the LDAP base install directory.
--enable-mailparse: Enable mailparse support.
--enable-mbstring: Enable multibyte string support.
--enable-mbstr-enc-trans: Enable japanese encoding translation.
--with-mcal[=DIR]: Include MCAL support.
--with-mcrypt[=DIR]: Include mcrypt support. DIR is the mcrypt install directory.
--with-mhash[=DIR]: Include mhash support. DIR is the mhash install directory.
--with-mnogosearch[=DIR]: Include mnoGoSearch support. DIR is the mnoGoSearch base install directory, defaults to /usr/local/mnogosearch.
--with-muscat[=DIR]: Include muscat support.
--with-ncurses: Include ncurses support.
--enable-pcntl: Enable experimental pcntl support (CGI ONLY!)
--without-pcre-regex: Do not include Perl Compatible Regular Expressions support. Use --with-pcre-regex=DIR to specify DIR where PCRE's include and library files are located, if not using bundled library.
--with-pfpro[=DIR]: Include Verisign Payflow Pro support.
--disable-posix: Disable POSIX-like functions.
--with-pspell[=DIR]: Include PSPELL support.
--with-qtdom: Include QtDOM support (requires Qt >= 2.2.0).
--with-libedit[=DIR]: Include libedit readline replacement.
--with-readline[=DIR]: Include readline support. DIR is the readline install directory.
--with-recode[=DIR]: Include recode support. DIR is the recode install directory.
--with-satellite[=DIR]: Enable CORBA support via Satellite (EXPERIMENTAL) DIR is the base directory for ORBit.
--with-mm[=DIR]: Include mm support for session storage.
--enable-trans-sid: Enable transparent session id propagation.
--disable-session: Disable session support.
--enable-shmop: Enable shmop support.
--with-snmp[=DIR]: Include SNMP support. DIR is the SNMP base install directory, defaults to searching through a number of common locations for the snmp install. Set DIR to shared to build as a dl, or shared,DIR to build as a dl and still specify DIR.
--enable-ucd-snmp-hack: Enable UCD SNMP hack.
--enable-sockets: Enable sockets support.
--with-regex=TYPE: regex library type: system, apache, php.
--with-system-regex: Use system regex library (deprecated).
--enable-sysvsem: Enable System V semaphore support.
--enable-sysvshm: Enable the System V shared memory support.
--with-vpopmail[=DIR]: Include vpopmail support.
--with-tsrm-pthreads: Use POSIX threads (default).
--enable-shared[=PKGS]: Build shared libraries [default=yes].
--enable-static[=PKGS]: Build static libraries [default=yes].
--enable-fast-install[=PKGS]: Optimize for fast installation [default=yes].
--with-gnu-ld: Assume the C compiler uses GNU ld [default=no].
--disable-libtool-lock: Avoid locking (might break parallel builds).
--with-pic: Try to use only PIC/non-PIC objects [default=use both].
--with-yaz[=DIR]: Include YAZ support (ANSI/NISO Z39.50). DIR is the YAZ bin install directory.
--enable-memory-limit: Compile with memory limit support.
--disable-url-fopen-wrapper: Disable the URL-aware fopen wrapper that allows accessing files via HTTP or FTP.
--enable-versioning: Export only required symbols. See INSTALL for more information.
--disable-bcmath: Compile without bc style precision math functions. PHP 3 only!
--with-imsp[=DIR]: Include IMSp support (DIR is IMSP's include dir and libimsp.a dir). PHP 3 only!
--with-ftp: Include FTP support. PHP 3 only!
--with-mck[=DIR]: Include Cybercash MCK support. DIR is the cybercash mck build directory, defaults to /usr/src/mck-3.2.0.3-linux for help look in extra/cyberlib. PHP 3 only!
--disable-overload: Disable user-space object overloading support. PHP 3 only!
--enable-yp: Include YP support. PHP 3 only!
--with-zip: Include ZIP support (requires zziplib >= 0.10.6). PHP 3 only!
--with-mod-dav=DIR: Include DAV support through Apache's mod_dav, DIR is mod_dav's installation directory (Apache module version only!) PHP 3 only!
--enable-debugger: Compile with remote debugging functions. PHP 3 only!
--enable-versioning: Take advantage of versioning and scoping provided by Solaris 2.x and Linux. PHP 3 only!

PHP options

--enable-maintainer-mode: Enable make rules and dependencies not useful (and sometimes confusing) to the casual installer.
--with-config-file-path=PATH: Sets the path in which to look for php.ini, defaults to PREFIX/lib.
--enable-safe-mode: Enable safe mode by default.
--with-exec-dir[=DIR]: Only allow executables in DIR when in safe mode defaults to /usr/local/php/bin.
--enable-magic-quotes: Enable magic quotes by default.
--disable-short-tags: Disable the short-form <? start tag by default.

Server options

--with-aolserver=DIR: Specify path to the installed AOLserver.
--with-apxs[=FILE]: Build shared Apache module. FILE is the optional pathname to the Apache apxs tool; defaults to apxs. Make sure you specify the version of apxs that is actually installed on your system and NOT the one that is in the apache source tarball.
--with-apache[=DIR]: Build Apache module. DIR is the top-level Apache build directory, defaults to /usr/local/apache.
--with-mod_charset: Enable transfer tables for mod_charset (Rus Apache).
--with-apxs2[=FILE]: Build shared Apache 2.0 module. FILE is the optional pathname to the Apache apxs tool; defaults to apxs.
--with-fhttpd[=DIR]: Build fhttpd module. DIR is the fhttpd sources directory, defaults to /usr/local/src/fhttpd.
--with-isapi=DIR: Build PHP as an ISAPI module for use with Zeus.
--with-nsapi=DIR: Specify path to the installed Netscape Server.
--with-phttpd=DIR: No information yet.
--with-pi3web=DIR: Build PHP as a module for use with Pi3Web.
--with-roxen=DIR: Build PHP as a Pike module. DIR is the base Roxen directory, normally /usr/local/roxen/server.
--enable-roxen-zts: Build the Roxen module using Zend Thread Safety.
--with-servlet[=DIR]: Include servlet support. DIR is the base install directory for the JSDK. This SAPI prereqs the java extension must be built as a shared dl.
--with-thttpd=SRCDIR: Build PHP as thttpd module.
--with-tux=MODULEDIR: Build PHP as a TUX module (Linux only).

XML options

--with-dom[=DIR]: Include DOM support (requires libxml >= 2.4.2). DIR is the libxml install directory, defaults to /usr.
--disable-xml: Disable XML support using bundled expat lib.
--with-expat-dir=DIR: XML: external libexpat install dir.
--with-xmlrpc[=DIR]: Include XMLRPC-EPI support.
--enable-wddx: Enable WDDX support.

Kapitola 4. Configuration

The configuration file

The configuration file (called php3.ini in PHP 3.0, and simply php.ini as of PHP 4.0) is read when PHP starts up. For the server module versions of PHP, this happens only once when the web server is started. For the CGI and CLI version, it happens on every invocation.

The default location of php.ini is a compile time option (see the FAQ entry), but can be changed for the CGI and CLI version with the -c command line switch, see the chapter about using PHP from the command line. You can also use the environment variable PHPRC for an additionaly path to search for php.ini.

Not every PHP directive is documented below. For a list of all directives, please read your well commented php.ini file. You may want to view the latest php.ini here from CVS.

Poznámka: The default value for the PHP directive register_globals changed from on to off in PHP 4.2.0.

Příklad 4-1. php.ini example

; any text on a line after an unquoted semicolon (;) is ignored [php] ; section markers (text within square brackets) are also ignored ; Boolean values can be set to either: ; true, on, yes ; or false, off, no, none register_globals = off magic_quotes_gpc = yes ; you can enclose strings in double-quotes include_path = ".:/usr/local/lib/php" ; backslashes are treated the same as any other character include_path = ".;c:\php\lib"

When using PHP as an Apache module, you can also change the configuration settings using directives in Apache configuration files and .htaccess files (You will need "AllowOverride Options" or "AllowOverride All" privileges)

With PHP 3.0, there are Apache directives that correspond to each configuration setting in the php3.ini name, except the name is prefixed by "php3_".

With PHP 4.0, there are several Apache directives that allow you to change the PHP configuration from within the Apache configuration file itself.

php_value name value: This sets the value of the specified variable.
php_flag name on|off: This is used to set a Boolean configuration option.
php_admin_value name value: This sets the value of the specified variable. "Admin" configuration settings can only be set from within the main Apache configuration files, and not from .htaccess files.
php_admin_flag name on|off: This is used to set a Boolean configuration option.

Příklad 4-2. Apache configuration example

<IfModule mod_php4.c> php_value include_path ".:/usr/local/lib/php" php_flag safe_mode on </IfModule> <IfModule mod_php3.c> php3_include_path ".:/usr/local/lib/php" php3_safe_mode on </IfModule>

Poznámka: PHP constants do not exist outside of PHP. For example, in httpd.conf do not use PHP constants such as E_ALL or E_NOTICE to set the error_reporting directive as they will have no meaning and will evaluate to 0. Use the associated bitmask values instead. These constants can be used in php.ini

You can view the settings of the configuration values in the output of phpinfo(). You can also access the values of individual configuration settings using ini_get() or get_cfg_var().

General Configuration Directives

allow_url_fopen boolean

This option enables the URL-aware fopen wrappers that enable accessing URL object like files. Default wrappers are provided for the access of remote files using the ftp or http protocol, some extensions like zlib may register additional wrappers.

Poznámka: This option was introduced immediately after the release of version 4.0.3. For versions up to and including 4.0.3 you can only disable this feature at compile time by using the configuration switch --disable-url-fopen-wrapper.

Varování

On Windows, the following functions do not support remote file accesing: include(), include_once(), require() and require_once().

asp_tags boolean

Enables the use of ASP-like <% %> tags in addition to the usual <?php ?> tags. This includes the variable-value printing shorthand of <%= $value %>. For more information, see Escaping from HTML.

Poznámka: Support for ASP-style tags was added in 3.0.4.

auto_append_file string

Specifies the name of a file that is automatically parsed after the main file. The file is included as if it was called with the include() function, so include_path is used.

The special value none disables auto-appending.

Poznámka: If the script is terminated with exit(), auto-append will not occur.

auto_prepend_file string

Specifies the name of a file that is automatically parsed before the main file. The file is included as if it was called with the include() function, so include_path is used.

The special value none disables auto-prepending.

disable_functions string

This directive allows you to disable certain functions for security reasons. It takes on a comma-dilimited list of function names. disable_functions is not affected by Safe Mode.

This directive must be set in php.ini For example, you cannot set this in httpd.conf.

display_errors boolean

This determines whether errors should be printed to the screen as part of the HTML output or not.

doc_root string

PHP's "root directory" on the server. Only used if non-empty. If PHP is configured with safe mode, no files outside this directory are served.

engine boolean

This directive is really only useful in the Apache module version of PHP. It is used by sites that would like to turn PHP parsing on and off on a per-directory or per-virtual server basis. By putting engine off in the appropriate places in the httpd.conf file, PHP can be enabled or disabled.

error_log string

Name of file where script errors should be logged. If the special value syslog is used, the errors are sent to the system logger instead. On UNIX, this means syslog(3) and on Windows NT it means the event log. The system logger is not supported on Windows 95.

error_reporting integer

Set the error reporting level. The parameter is either an integer representing a bit field, or named constants. The error_reporting levels and constants are described in the Error Handling section of the manual, and in php.ini. To set at runtime, use the error_reporting() function. See also the display_errors directive.

The default value does not show E_NOTICE level errors. You may want to show them during development.

file_uploads boolean

Whether or not to allow HTTP file uploads. See also the upload_max_filesize, upload_tmp_dir, and post_max_size directives.

html_errors boolean

Turn off HTML tags in error messages.

open_basedir string

Limit the files that can be opened by PHP to the specified directory-tree.

When a script tries to open a file with, for example, fopen or gzopen, the location of the file is checked. When the file is outside the specified directory-tree, PHP will refuse to open it. All symbolic links are resolved, so it's not possible to avoid this restriction with a symlink.

The special value . indicates that the directory in which the script is stored will be used as base-directory.

Under Windows, separate the directories with a semicolon. On all other systems, separate the directories with a colon. As an Apache module, open_basedir paths from parent directories are now automatically inherited.

The restriction specified with open_basedir is actually a prefix, not a directory name. This means that "open_basedir = /dir/incl" also allows access to "/dir/include" and "/dir/incls" if they exist. When you want to restrict access to only the specified directory, end with a slash. For example: "open_basedir = /dir/incl/"

Poznámka: Support for multiple directories was added in 3.0.7.

The default is to allow all files to be opened.

gpc_order string

Set the order of GET/POST/COOKIE variable parsing. The default setting of this directive is "GPC". Setting this to "GP", for example, will cause PHP to completely ignore cookies and to overwrite any GET method variables with POST-method variables of the same name.

Note, that this option is not available in PHP 4. Use variables_order instead.

variables_order string

Set the order of the EGPCS (Environment, GET, POST, Cookie, Server) variable parsing. The default setting of this directive is "EGPCS". Setting this to "GP", for example, will cause PHP to completely ignore environment variables, cookies and server variables, and to overwrite any GET method variables with POST-method variables of the same name.

Safe Mode Configuration Directives

safe_mode boolean

Whether to enable PHP's safe mode. Read the Security and Safe Mode chapters for more information.

safe_mode_gid boolean

Whether to use UID (FALSE) or GID (TRUE) checking upon file access. See Safe Mode for more information.

safe_mode_exec_dir string

If PHP is used in safe mode, system() and the other functions executing system programs refuse to start programs that are not in this directory.

safe_mode_include_dir string

UID/GID checks are bypassed when including files from this directory and its subdirectories (directory must also be in include_path or full path must including).

As of PHP 4.2.0, this directive can take on a semi-colon separated path in a similar fashion to the include_path directive, rather than just a single directory.

Debugger Configuration Directives

debugger.host string: DNS name or IP address of host used by the debugger.
debugger.port string: Port number used by the debugger.
debugger.enabled boolean: Whether the debugger is enabled.

Extension Loading Directives

enable_dl boolean

This directive is really only useful in the Apache module version of PHP. You can turn dynamic loading of PHP extensions with dl() on and off per virtual server or per directory.

The main reason for turning dynamic loading off is security. With dynamic loading, it's possible to ignore all the safe_mode and open_basedir restrictions.

The default is to allow dynamic loading, except when using safe-mode. In safe-mode, it's always imposible to use dl().

extension_dir string

In what directory PHP should look for dynamically loadable extensions.

extension string

Which dynamically loadable extensions to load when PHP starts up.

mSQL Configuration Directives

msql.allow_persistent boolean: Whether to allow persistent mSQL connections.
msql.max_persistent integer: The maximum number of persistent mSQL connections per process.
msql.max_links integer: The maximum number of mSQL connections per process, including persistent connections.

Postgres Configuration Directives

pgsql.allow_persistent boolean: Whether to allow persistent Postgres connections.
pgsql.max_persistent integer: The maximum number of persistent Postgres connections per process.
pgsql.max_links integer: The maximum number of Postgres connections per process, including persistent connections.

SESAM Configuration Directives

sesam_oml string

Name of BS2000 PLAM library containing the loadable SESAM driver modules. Required for using SESAM functions. The BS2000 PLAM library must be set ACCESS=READ,SHARE=YES because it must be readable by the apache server's user id.

sesam_configfile string

Name of SESAM application configuration file. Required for using SESAM functions. The BS2000 file must be readable by the apache server's user id.

The application configuration file will usually contain a configuration like (see SESAM reference manual):

CNF=B
NAM=K
NOTYPE

sesam_messagecatalog string

Name of SESAM message catalog file. In most cases, this directive is not neccessary. Only if the SESAM message file is not installed in the system's BS2000 message file table, it can be set with this directive.

The message catalog must be set ACCESS=READ,SHARE=YES because it must be readable by the apache server's user id.

Sybase Configuration Directives

sybase.allow_persistent boolean: Whether to allow persistent Sybase connections.
sybase.max_persistent integer: The maximum number of persistent Sybase connections per process.
sybase.max_links integer: The maximum number of Sybase connections per process, including persistent connections.

Sybase-CT Configuration Directives

sybct.allow_persistent boolean: Whether to allow persistent Sybase-CT connections. The default is on.
sybct.max_persistent integer: The maximum number of persistent Sybase-CT connections per process. The default is -1 meaning unlimited.
sybct.max_links integer: The maximum number of Sybase-CT connections per process, including persistent connections. The default is -1 meaning unlimited.
sybct.min_server_severity integer: Server messages with severity greater than or equal to sybct.min_server_severity will be reported as warnings. This value can also be set from a script by calling sybase_min_server_severity(). The default is 10 which reports errors of information severity or greater.
sybct.min_client_severity integer: Client library messages with severity greater than or equal to sybct.min_client_severity will be reported as warnings. This value can also be set from a script by calling sybase_min_client_severity(). The default is 10 which effectively disables reporting.
sybct.login_timeout integer: The maximum time in seconds to wait for a connection attempt to succeed before returning failure. Note that if max_execution_time has been exceeded when a connection attempt times out, your script will be terminated before it can take action on failure. The default is one minute.
sybct.timeout integer: The maximum time in seconds to wait for a select_db or query operation to succeed before returning failure. Note that if max_execution_time has been exceeded when am operation times out, your script will be terminated before it can take action on failure. The default is no limit.
sybct.hostname string: The name of the host you claim to be connecting from, for display by sp_who. The default is none.

Informix Configuration Directives

ifx.allow_persistent boolean: Whether to allow persistent Informix connections.
ifx.max_persistent integer: The maximum number of persistent Informix connections per process.
ifx.max_links integer: The maximum number of Informix connections per process, including persistent connections.
ifx.default_host string: The default host to connect to when no host is specified in ifx_connect() or ifx_pconnect().
ifx.default_user string: The default user id to use when none is specified in ifx_connect() or ifx_pconnect().
ifx.default_password string: The default password to use when none is specified in ifx_connect() or ifx_pconnect().
ifx.blobinfile boolean: Set to TRUE if you want to return blob columns in a file, FALSE if you want them in memory. You can override the setting at runtime with ifx_blobinfile_mode().
ifx.textasvarchar boolean: Set to TRUE if you want to return TEXT columns as normal strings in select statements, FALSE if you want to use blob id parameters. You can override the setting at runtime with ifx_textasvarchar().
ifx.byteasvarchar boolean: Set to TRUE if you want to return BYTE columns as normal strings in select queries, FALSE if you want to use blob id parameters. You can override the setting at runtime with ifx_textasvarchar().
ifx.charasvarchar boolean: Set to TRUE if you want to trim trailing spaces from CHAR columns when fetching them.
ifx.nullformat boolean: Set to TRUE if you want to return NULL columns as the literal string "NULL", FALSE if you want them returned as the empty string "". You can override this setting at runtime with ifx_nullformat().

BC Math Configuration Directives

bcmath.scale integer: Number of decimal digits for all bcmath functions.

Browser Capability Configuration Directives

browscap string: Name of browser capabilities file. See also get_browser().

Multi-Byte String Configuration Directives

mbstring.internal_encoding string: mbstring.internal_encoding defines default internal character encoding.
mbstring.http_input string: mbstring.http_input defines default HTTP input character encoding.
mbstring.http_output string: mbstring.http_output defines default HTTP output character encoding.
mbstring.detect_order string: mbstring.detect_order defines default character encoding detection order.
mbstring.substitute_character string: mbstring.substitute_character defines character to substitute for invalid character codes.

Exif Configuration Directives

Exif supports automatically conversion for Unicode and JIS character encodings of user comments when module mbstring is available. This is done by first decoding the comment using the specified characterset. The result is then encoded with another characterset which should match your HTTP output.

exif.encode_unicode string: exif.encode_unicode defines the characterset UNICODE user comments are handled. This defaults to ISO-8859-15 which should work for most non asian countries. The setting can be empty or must be an encoding supported by mbstring. If it is empty the current internal encoding of mbstring is used.
exif.decode_unicode_motorola string: exif.decode_unicode_motorola defines the image internal characterset for Unicode encoded user comments if image is in motorola byte order (big-endian). This setting cannot be empty but you can specify a list of encodings supported by mbstring. The default is UCS-2BE.
exif.decode_unicode_intel string: exif.decode_unicode_intel defines the image internal characterset for Unicode encoded user comments if image is in intel byte order (little-endian). This setting cannot be empty but you can specify a list of encodings supported by mbstring. The default is UCS-2LE.
exif.encode_jis string: exif.encode_jis defines the characterset JIS user comments are handled. This defaults to an empty value which forces the functions to use the current internal encoding of mbstring.
exif.decode_jis_motorola string: exif.decode_jis_motorola defines the image internal characterset for JIS encoded user comments if image is in motorola byte order (big-endian). This setting cannot be empty but you can specify a list of encodings supported by mbstring. The default is JIS.
exif.decode_jis_intel string: exif.decode_jis_intel defines the image internal characterset for JIS encoded user comments if image is in intel byte order (little-endian). This setting cannot be empty but you can specify a list of encodings supported by mbstring. The default is JIS.

Kapitola 5. Security

PHP is a powerful language and the interpreter, whether included in a web server as a module or executed as a separate CGI binary, is able to access files, execute commands and open network connections on the server. These properties make anything run on a web server insecure by default. PHP is designed specifically to be a more secure language for writing CGI programs than Perl or C, and with correct selection of compile-time and runtime configuration options, and proper coding practices, it can give you exactly the combination of freedom and security you need.

As there are many different ways of utilizing PHP, there are many configuration options controlling its behaviour. A large selection of options guarantees you can use PHP for a lot of purposes, but it also means there are combinations of these options and server configurations that result in an insecure setup.

The configuration flexibility of PHP is equally rivalled by the code flexibility. PHP can be used to build complete server applications, with all the power of a shell user, or it can be used for simple server-side includes with little risk in a tightly controlled environment. How you build that environment, and how secure it is, is largely up to the PHP developer.

This chapter starts with some general security advice, explains the different configuration option combinations and the situations they can be safely used, and describes different considerations in coding for different levels of security.

General considerations

A completely secure system is a virtual impossibility, so an approach often used in the security profession is one of balancing risk and usability. If every variable submitted by a user required two forms of biometric validation (such as a retinal scan and a fingerprint), you would have an extremely high level of accountability. It would also take half an hour to fill out a fairly complex form, which would tend to encourage users to find ways of bypassing the security.

The best security is often inobtrusive enough to suit the requirements without the user being prevented from accomplishing their work, or over-burdening the code author with excessive complexity. Indeed, some security attacks are merely exploits of this kind of overly built security, which tends to erode over time.

A phrase worth remembering: A system is only as good as the weakest link in a chain. If all transactions are heavily logged based on time, location, transaction type, etc. but the user is only verified based on a single cookie, the validity of tying the users to the transaction log is severely weakened.

When testing, keep in mind that you will not be able to test all possibilities for even the simplest of pages. The input you may expect will be completely unrelated to the input given by a disgruntled employee, a cracker with months of time on their hands, or a housecat walking across the keyboard. This is why it's best to look at the code from a logical perspective, to discern where unexpected data can be introduced, and then follow how it is modified, reduced, or amplified.

The Internet is filled with people trying to make a name for themselves by breaking your code, crashing your site, posting inappropriate content, and otherwise making your day interesting. It doesn't matter if you have a small or large site, you are a target by simply being online, by having a server that can be connected to. Many cracking programs do not discern by size, they simply trawl massive IP blocks looking for victims. Try not to become one.

Installed as CGI binary

Possible attacks

Using PHP as a CGI binary is an option for setups that for some reason do not wish to integrate PHP as a module into server software (like Apache), or will use PHP with different kinds of CGI wrappers to create safe chroot and setuid environments for scripts. This setup usually involves installing executable PHP binary to the web server cgi-bin directory. CERT advisory CA-96.11 recommends against placing any interpreters into cgi-bin. Even if the PHP binary can be used as a standalone interpreter, PHP is designed to prevent the attacks this setup makes possible:

Accessing system files: http://my.host/cgi-bin/php?/etc/passwd

The query information in a url after the question mark (?) is passed as command line arguments to the interpreter by the CGI interface. Usually interpreters open and execute the file specified as the first argument on the command line.

When invoked as a CGI binary, PHP refuses to interpret the command line arguments.
Accessing any web document on server: http://my.host/cgi-bin/php/secret/doc.html

The path information part of the url after the PHP binary name, /secret/doc.html is conventionally used to specify the name of the file to be opened and interpreted by the CGI program. Usually some web server configuration directives (Apache: Action) are used to redirect requests to documents like http://my.host/secret/script.php to the PHP interpreter. With this setup, the web server first checks the access permissions to the directory /secret, and after that creates the redirected request http://my.host/cgi-bin/php/secret/script.php. Unfortunately, if the request is originally given in this form, no access checks are made by web server for file /secret/script.php, but only for the /cgi-bin/php file. This way any user able to access /cgi-bin/php is able to access any protected document on the web server.

In PHP, compile-time configuration option --enable-force-cgi-redirect and runtime configuration directives doc_root and user_dir can be used to prevent this attack, if the server document tree has any directories with access restrictions. See below for full the explanation of the different combinations.

Case 1: only public files served

If your server does not have any content that is not restricted by password or ip based access control, there is no need for these configuration options. If your web server does not allow you to do redirects, or the server does not have a way to communicate to the PHP binary that the request is a safely redirected request, you can specify the option --enable-force-cgi-redirect to the configure script. You still have to make sure your PHP scripts do not rely on one or another way of calling the script, neither by directly http://my.host/cgi-bin/php/dir/script.php nor by redirection http://my.host/dir/script.php.

Redirection can be configured in Apache by using AddHandler and Action directives (see below).

Case 2: using --enable-force-cgi-redirect

This compile-time option prevents anyone from calling PHP directly with a url like http://my.host/cgi-bin/php/secretdir/script.php. Instead, PHP will only parse in this mode if it has gone through a web server redirect rule.

Usually the redirection in the Apache configuration is done with the following directives:

Action php-script /cgi-bin/php
AddHandler php-script .php

This option has only been tested with the Apache web server, and relies on Apache to set the non-standard CGI environment variable REDIRECT_STATUS on redirected requests. If your web server does not support any way of telling if the request is direct or redirected, you cannot use this option and you must use one of the other ways of running the CGI version documented here.

Case 3: setting doc_root or user_dir

To include active content, like scripts and executables, in the web server document directories is sometimes consider an insecure practice. If, because of some configuration mistake, the scripts are not executed but displayed as regular HTML documents, this may result in leakage of intellectual property or security information like passwords. Therefore many sysadmins will prefer setting up another directory structure for scripts that are accessible only through the PHP CGI, and therefore always interpreted and not displayed as such.

Also if the method for making sure the requests are not redirected, as described in the previous section, is not available, it is necessary to set up a script doc_root that is different from web document root.

You can set the PHP script document root by the configuration directive doc_root in the configuration file, or you can set the environment variable PHP_DOCUMENT_ROOT. If it is set, the CGI version of PHP will always construct the file name to open with this doc_root and the path information in the request, so you can be sure no script is executed outside this directory (except for user_dir below).

Another option usable here is user_dir. When user_dir is unset, only thing controlling the opened file name is doc_root. Opening an url like http://my.host/~user/doc.php does not result in opening a file under users home directory, but a file called ~user/doc.php under doc_root (yes, a directory name starting with a tilde [~]).

If user_dir is set to for example public_php, a request like http://my.host/~user/doc.php will open a file called doc.php under the directory named public_php under the home directory of the user. If the home of the user is /home/user, the file executed is /home/user/public_php/doc.php.

user_dir expansion happens regardless of the doc_root setting, so you can control the document root and user directory access separately.

Case 4: PHP parser outside of web tree

A very secure option is to put the PHP parser binary somewhere outside of the web tree of files. In /usr/local/bin, for example. The only real downside to this option is that you will now have to put a line similar to:

#!/usr/local/bin/php

as the first line of any file containing PHP tags. You will also need to make the file executable. That is, treat it exactly as you would treat any other CGI script written in Perl or sh or any other common scripting language which uses the #! shell-escape mechanism for launching itself.

To get PHP to handle PATH_INFO and PATH_TRANSLATED information correctly with this setup, the php parser should be compiled with the --enable-discard-path configure option.

Installed as an Apache module

When PHP is used as an Apache module it inherits Apache's user permissions (typically those of the "nobody" user). This has several impacts on security and authorization. For example, if you are using PHP to access a database, unless that database has built-in access control, you will have to make the database accessable to the "nobody" user. This means a malicious script could access and modify the database, even without a username and password. It's entirely possible that a web spider could stumble across a database administrator's web page, and drop all of your databases. You can protect against this with Apache authorization, or you can design your own access model using LDAP, .htaccess files, etc. and include that code as part of your PHP scripts.

Often, once security is established to the point where the PHP user (in this case, the apache user) has very little risk attached to it, it is discovered that PHP is now prevented from writing any files to user directories. Or perhaps it has been prevented from accessing or changing databases. It has equally been secured from writing good and bad files, or entering good and bad database transactions.

A frequent security mistake made at this point is to allow apache root permissions, or to escalate apache's abilitites in some other way.

Escalating the Apache user's permissions to root is extremely dangerous and may compromise the entire system, so sudo'ing, chroot'ing, or otherwise running as root should not be considered by those who are not security professionals.

There are some simpler solutions. By using open_basedir you can control and restrict what directories are allowed to be used for PHP. You can also set up apache-only areas, to restrict all web based activity to non-user, or non-system, files.

Filesystem Security

PHP is subject to the security built into most server systems with respect to permissions on a file and directory basis. This allows you to control which files in the filesystem may be read. Care should be taken with any files which are world readable to ensure that they are safe for reading by all users who have access to that filesystem.

Since PHP was designed to allow user level access to the filesystem, it's entirely possible to write a PHP script that will allow you to read system files such as /etc/passwd, modify your ethernet connections, send massive printer jobs out, etc. This has some obvious implications, in that you need to ensure that the files that you read from and write to are the appropriate ones.

Consider the following script, where a user indicates that they'd like to delete a file in their home directory. This assumes a situation where a PHP web interface is regularly used for file management, so the Apache user is allowed to delete files in the user home directories.

Příklad 5-1. Poor variable checking leads to....

<?php // remove a file from the user's home directory $username = $_POST['user_submitted_name']; $homedir = "/home/$username"; $file_to_delete = "$userfile"; unlink ($homedir/$userfile); echo "$file_to_delete has been deleted!"; ?>
Since the username is postable from a user form, they can submit a username and file belonging to someone else, and delete files. In this case, you'd want to use some other form of authentication. Consider what could happen if the variables submitted were "../etc/" and "passwd". The code would then effectively read:

Příklad 5-2. ... A filesystem attack

<?php // removes a file from anywhere on the hard drive that // the PHP user has access to. If PHP has root access: $username = "../etc/"; $homedir = "/home/../etc/"; $file_to_delete = "passwd"; unlink ("/home/../etc/passwd"); echo "/home/../etc/passwd has been deleted!"; ?>
There are two important measures you should take to prevent these issues.

Only allow limited permissions to the PHP web user binary.
Check all variables which are submitted.

Here is an improved script:

Příklad 5-3. More secure file name checking

<?php
// removes a file from the hard drive that
// the PHP user has access to.
$username = $_SERVER['REMOTE_USER']; // using an authentication mechanisim

$homedir = "/home/$username";

$file_to_delete = basename("$userfile"); // strip paths
unlink ($homedir/$file_to_delete);

$fp = fopen("/home/logging/filedelete.log","+a"); //log the deletion
$logstring = "$username $homedir $file_to_delete";
fputs ($fp, $logstring);
fclose($fp);

echo "$file_to_delete has been deleted!";
?>

However, even this is not without it's flaws. If your authentication system allowed users to create their own user logins, and a user chose the login "../etc/", the system is once again exposed. For this reason, you may prefer to write a more customized check:

Příklad 5-4. More secure file name checking

<?php
$username = $_SERVER['REMOTE_USER']; // using an authentication mechanisim
$homedir = "/home/$username";

if (!ereg('^[^./][^/]*$', $userfile))
     die('bad filename'); //die, do not process

if (!ereg('^[^./][^/]*$', $username))
     die('bad username'); //die, do not process
//etc...
?>

Depending on your operating system, there are a wide variety of files which you should be concerned about, including device entries (/dev/ or COM1), configuration files (/etc/ files and the .ini files), well known file storage areas (/home/, My Documents), etc. For this reason, it's usually easier to create a policy where you forbid everything except for what you explicitly allow.

Database Security

Nowadays, databases are cardinal components of any web based application by enabling websites to provide varying dynamic content. Since very sensitive or secret informations can be stored in such database, you should strongly consider to protect them somehow.

To retrieve or to store any information you need to connect to the database, send a legitimate query, fetch the result, and close the connecion. Nowadays, the commonly used query language in this interaction is the Structured Query Language (SQL). See how an attacker can tamper with an SQL query.

As you can realize, PHP cannot protect your database by itself. The following sections aim to be an introduction into the very basics of how to access and manipulate databases within PHP scripts.

Keep in mind this simple rule: defence in depth. In the more place you take the more action to increase the protection of your database, the less probability of that an attacker succeeds, and exposes or abuse any stored secret information. Good design of the database schema and the application deals with your greatest fears.

Designing Databases

The first step is always to create the database, unless you want to use an existing third party's one. When a database is created, it is assigned to an owner, who executed the creation statement. Usually, only the owner (or a superuser) can do anything with the objects in that database, and in order to allow other users to use it, privileges must be granted.

Applications should never connect to the database as its owner or a superuser, because these users can execute any query at will, for example, modifying the schema (e.g. dropping tables) or deleting its entire content.

You may create different database users for every aspect of your application with very limited rights to database objects. The most required privileges should be granted only, and avoid that the same user can interact with the database in different use cases. This means that if intruders gain access to your database using one of these credentials, they can only effect as many changes as your application can.

You are encouraged not to implement all the business logic in the web application (i.e. your script), instead to do it in the database schema using views, triggers or rules. If the system evolves, new ports will be intended to open to the database, and you have to reimplement the logic in each separate database client. Over and above, triggers can be used to transparently and automatically handle fields, which often provides insight when debugging problems with your application or tracing back transactions.

Connecting to Database

You may want to estabilish the connections over SSL to encrypt client/server communications for increased security, or you can use ssh to encrypt the network connection between clients and the database server. If either of them is done, then monitoring your traffic and gaining informations in this way will be a hard work.

Encrypted Storage Model

SSL/SSH protects data travelling from the client to the server, SSL/SSH does not protect the persistent data stored in a database. SSL is an on-the-wire protocol.

Once an attacker gains access to your database directly (bypassing the webserver), the stored sensitive data may be exposed or misused, unless the information is protected by the database itself. Encrypting the data is a good way to mitigate this threat, but very few databases offer this type of data encryption.

The easiest way to work around this problem is to first create your own encryption package, and then use it from within your PHP scripts. PHP can assist you in this case with its several extensions, such as Mcrypt and Mhash, covering a wide variety of encryption algorithms. The script encrypts the data be stored first, and decrypts it when retrieving. See the references for further examples how encryption works.

In case of truly hidden data, if its raw representation is not needed (i.e. not be displayed), hashing may be also taken into consideration. The well-known example for the hashing is storing the MD5 hash of a password in a database, instead of the password itself. See also crypt() and md5().

Příklad 5-5. Using hashed password field

// storing password hash
$query  = sprintf("INSERT INTO users(name,pwd) VALUES('%s','%s');",
            addslashes($username), md5($password));
$result = pg_exec($connection, $query);

// querying if user submitted the right password
$query = sprintf("SELECT 1 FROM users WHERE name='%s' AND pwd='%s';",
            addslashes($username), md5($password));
$result = pg_exec($connection, $query);

if (pg_numrows($result) > 0) {
    echo "Welcome, $username!";
}
else {
    echo "Authentication failed for $username.";
}

SQL Injection

Many web developers are unaware of how SQL queries can be tampered with, and assume that an SQL query is a trusted command. It means that SQL queries are able to circumvent access controls, thereby bypassing standard authentication and authorization checks, and sometimes SQL queries even may allow access to host operating system level commands.

Direct SQL Command Injection is a technique where an attacker creates or alters existing SQL commands to expose hidden data, or to override valuable ones, or even to execute dangerous system level commands on the database host. This is accomplished by the application taking user input and combining it with static parameters to build a SQL query. The following examples are based on true stories, unfortunately.

Owing to the lack of input validation and connecting to the database on behalf of a superuser or the one who can create users, the attacker may create a superuser in your database.

Příklad 5-6. Splitting the result set into pages ... and making superusers (PostgreSQL and MySQL)

$offset = argv[0]; // beware, no input validation! $query = "SELECT id, name FROM products ORDER BY name LIMIT 20 OFFSET $offset;"; // with PostgreSQL $result = pg_exec($conn, $query); // with MySQL $result = mysql_query($query);
Normal users click on the 'next', 'prev' links where the $offset is encoded into the URL. The script expects that the incoming $offset is decimal number. However, someone tries to break in with appending urlencode()'d form of the following to the URL

// in case of PostgreSQL
0;
insert into pg_shadow(usename,usesysid,usesuper,usecatupd,passwd)
    select 'crack', usesysid, 't','t','crack'
    from pg_shadow where usename='postgres';
--

// in case of MySQL
0;
UPDATE user SET Password=PASSWORD('crack') WHERE user='root';
FLUSH PRIVILEGES;

If it happened, then the script would present a superuser access to him. Note that 0; is to supply a valid offset to the original query and to terminate it.

Poznámka: It is common technique to force the SQL parser to ignore the rest of the query written by the developer with -- which is the comment sign in SQL.

A feasible way to gain passwords is to circumvent your search result pages. What the attacker needs only is to try if there is any submitted variable used in SQL statement which is not handled properly. These filters can be set commonly in a preceding form to customize WHERE, ORDER BY, LIMIT and OFFSET clauses in SELECT statements. If your database supports the UNION construct, the attacker may try to append an entire query to the original one to list passwords from an arbitrary table. Using encrypted password fields is strongly encouraged.

Příklad 5-7. Listing out articles ... and some passwords (any database server)

$query = "SELECT id, name, inserted, size FROM products WHERE size = '$size' ORDER BY $order LIMIT $limit, $offset;"; $result = odbc_exec($conn, $query);
The static part of the query can be combined with another SELECT statement which reveals all passwords:

'
union select '1', concat(uname||'-'||passwd) as name, '1971-01-01', '0' from usertable;
--

If this query (playing with the ' and --) were assigned to one of the variables used in $query, the query beast awakened.

SQL UPDATEs are also subject to attacking your database. These queries are also threatened by chopping and appending an entirely new query to it. But the attacker might fiddle with the SET clause. In this case some schema information must be possessed to manipulate the query successfully. This can be acquired by examing the form variable names, or just simply brute forcing. There are not so many naming convention for fields storing passwords or usernames.

Příklad 5-8. From resetting a password ... to gaining more privileges (any database server)

$query = "UPDATE usertable SET pwd='$pwd' WHERE uid='$uid';";
But a malicious user sumbits the value ' or uid like'%admin%'; -- to $uid to change the admin's password, or simply sets $pwd to "hehehe', admin='yes', trusted=100 " (with a trailing space) to gain more privileges. Then, the query will be twisted:

// $uid == ' or uid like'%admin%'; --
$query = "UPDATE usertable SET pwd='...' WHERE uid='' or uid like '%admin%'; --";

// $pwd == "hehehe', admin='yes', trusted=100 "
$query = "UPDATE usertable SET pwd='hehehe', admin='yes', trusted=100 WHERE ...;"

A frightening example how operating system level commands can be accessed on some database hosts.

Příklad 5-9. Attacking the database host's operating system (MSSQL Server)

$query = "SELECT * FROM products WHERE id LIKE '%$prod%'"; $result = mssql_query($query);
If attacker submits the value a%' exec master..xp_cmdshell 'net user test testpass /ADD' -- to $prod, then the $query will be:

$query  = "SELECT * FROM products
                    WHERE id LIKE '%a%'
                    exec master..xp_cmdshell 'net user test testpass /ADD'--";
$result = mssql_query($query);

MSSQL Server executes the SQL statements in the batch including a command to add a new user to the local accounts database. If this application were running as sa and the MSSQLSERVER service is running with sufficient privileges, the attacker would now have an account with which to access this machine.

Poznámka: Some of the examples above is tied to a specific database server. This does not mean that a similar attack is impossible against other products. Your database server may be so vulnerable in other manner.

Avoiding techniques

You may plead that the attacker must possess a piece of information about the database schema in most examples. You are right, but you never know when and how it can be taken out, and if it happens, your database may be exposed. If you are using an open source, or publicly available database handling package, which may belong to a content management system or forum, the intruders easily produce a copy of a piece of your code. It may be also a security risk if it is a poorly designed one.

These attacks are mainly based on exploiting the code not being written with security in mind. Never trust on any kind of input, especially which comes from the client side, even though it comes from a select box, a hidden input field or a cookie. The first example shows that such a blameless query can cause disasters.

Never connect to the database as a superuser or as the database owner. Use always customized users with very limited privileges.
Check if the given input has the expected data type. PHP has a wide range of input validating functions, from the simplest ones found in Variable Functions and in Character Type Functions (e.g. is_numeric(), ctype_digit() respectively) onwards the Perl compatible Regular Expressions support.

If the application waits for numerical input, consider to verify data with is_numeric(), or silently change its type using settype(), or use its numeric representation by sprintf().

Příklad 5-10. A more secure way to compose a query for paging

settype($offset, 'integer'); $query = "SELECT id, name FROM products ORDER BY name LIMIT 20 OFFSET $offset;"; // please note %d in the format string, using %s would be meaningless $query = sprintf("SELECT id, name FROM products ORDER BY name LIMIT 20 OFFSET %d;", $offset);

Quote each non numeric user input which is passed to the database with addslashes() or addcslashes(). See the first example. As the examples shows, quotes burnt into the static part of the query is not enough, and can be easily hacked.
Do not print out any database specific information, especially about the schema, by fair means or foul. See also Error Reporting and Error Handling and Logging Functions.
You may use stored procedures and previously defined cursors to abstract data access so that users do not directly access tables or views, but this solution has another impacts.

Besides these, you benefit from logging queries either within your script or by the database itself, if it supports. Obviously, the logging is unable to prevent any harmful attempt, but it can be helpful to trace back which application has been circumvented. The log is not useful by itself, but through the information it contains. The more detail is generally better.

Error Reporting

With PHP security, there are two sides to error reporting. One is beneficial to increasing security, the other is detrimental.

A standard attack tactic involves profiling a system by feeding it improper data, and checking for the kinds, and contexts, of the errors which are returned. This allows the system cracker to probe for information about the server, to determine possible weaknesses. For example, if an attacker had gleaned information about a page based on a prior form submission, they may attempt to override variables, or modify them:

Příklad 5-11. Attacking Variables with a custom HTML page

<form method="post" action="attacktarget?username=badfoo&password=badfoo"> <input type="hidden" name="username" value="badfoo"> <input type="hidden" name="password" value="badfoo"> </form>

The PHP errors which are normally returned can be quite helpful to a developer who is trying to debug a script, indicating such things as the function or file that failed, the PHP file it failed in, and the line number which the failure occured in. This is all information that can be exploited. It is not uncommon for a php developer to use show_source(), highlight_string(), or highlight_file() as a debugging measure, but in a live site, this can expose hidden variables, unchecked syntax, and other dangerous information. Especially dangerous is running code from known sources with built-in debugging handlers, or using common debugging techniques. If the attacker can determine what general technique you are using, they may try to brute-force a page, by sending various common debugging strings:

Příklad 5-12. Exploiting common debugging variables

<form method="post" action="attacktarget?errors=Y&showerrors=1"&debug=1"> <input type="hidden" name="errors" value="Y"> <input type="hidden" name="showerrors" value="1"> <input type="hidden" name="debug" value="1"> </form>

Regardless of the method of error handling, the ability to probe a system for errors leads to providing an attacker with more information.

For example, the very style of a generic PHP error indicates a system is running PHP. If the attacker was looking at an .html page, and wanted to probe for the back-end (to look for known weaknesses in the system), by feeding it the wrong data they may be able to determine that a system was built with PHP.

A function error can indicate whether a system may be running a specific database engine, or give clues as to how a web page or programmed or designed. This allows for deeper investigation into open database ports, or to look for specific bugs or weaknesses in a web page. By feeding different pieces of bad data, for example, an attacker can determine the order of authentication in a script, (from the line number errors) as well as probe for exploits that may be exploited in different locations in the script.

A filesystem or general PHP error can indicate what permissions the webserver has, as well as the structure and organization of files on the web server. Developer written error code can aggravate this problem, leading to easy exploitation of formerly "hidden" information.

There are three major solutions to this issue. The first is to scrutinize all functions, and attempt to compensate for the bulk of the errors. The second is to disable error reporting entirely on the running code. The third is to use PHP's custom error handling functions to create your own error handler. Depending on your security policy, you may find all three to be applicable to your situation.

One way of catching this issue ahead of time is to make use of PHP's own error_reporting(), to help you secure your code and find variable usage that may be dangerous. By testing your code, prior to deployment, with E_ALL, you can quickly find areas where your variables may be open to poisoning or modification in other ways. Once you are ready for deployment, by using E_NONE, you insulate your code from probing.

Příklad 5-13. Finding dangerous variables with E_ALL

<?php if ($username) { // Not initialized or checked before usage $good_login = 1; } if ($good_login == 1) { // If above test fails, not initialized or checked before usage fpassthru ("/highly/sensitive/data/index.html"); } ?>

Using Register Globals

One feature of PHP that can be used to enhance security is configuring PHP with register_globals = off. By turning off the ability for any user-submitted variable to be injected into PHP code, you can reduce the amount of variable poisoning a potential attacker may inflict. They will have to take the additional time to forge submissions, and your internal variables are effectively isolated from user submitted data.

While it does slightly increase the amount of effort required to work with PHP, it has been argued that the benefits far outweigh the effort.

Příklad 5-14. Working without register_globals=off

<?php if ($username) { // can be forged by a user in get/post/cookies $good_login = 1; } if ($good_login == 1) { // can be forged by a user in get/post/cookies, fpassthru ("/highly/sensitive/data/index.html"); } ?>

Příklad 5-15. Working with register_globals = off

<?php if($_COOKIE['username']){ // can only come from a cookie, forged or otherwise $good_login = 1; fpassthru ("/highly/sensitive/data/index.html"); } ?>
By using this wisely, it's even possible to take preventative measures to warn when forging is being attempted. If you know ahead of time exactly where a variable should be coming from, you can check to see if submitted data is coming from an inappropriate kind of submission. While it doesn't guarantee that data has not been forged, it does require an attacker to guess the right kind of forging.

Příklad 5-16. Detecting simple variable poisoning

<?php if ($_COOKIE['username'] && !$_POST['username'] && !$_GET['username'] ) { // Perform other checks to validate the user name... $good_login = 1; fpassthru ("/highly/sensitive/data/index.html"); } else { mail("admin@example.com", "Possible breakin attempt", $_SERVER['REMOTE_ADDR']); echo "Security violation, admin has been alerted."; exit; } ?>
Of course, simply turning off register_globals does not mean code is secure. For every piece of data that is submitted, it should also be checked in other ways.

User Submitted Data

The greatest weakness in many PHP programs is not inherent in the language itself, but merely an issue of code not being written with security in mind. For this reason, you should always take the time to consider the implications of a given piece of code, to ascertain the possible damage if an unexpected variable is submitted to it.

Příklad 5-17. Dangerous Variable Usage

<?php // remove a file from the user's home directory... or maybe // somebody else's? unlink ($evil_var); // Write logging of their access... or maybe an /etc/passwd entry? fputs ($fp, $evil_var); // Execute something trivial.. or rm -rf *? system ($evil_var); exec ($evil_var); ?>
You should always carefully examine your code to make sure that any variables being submitted from a web browser are being properly checked, and ask yourself the following questions:

Will this script only affect the intended files?
Can unusual or undesirable data be acted upon?
Can this script be used in unintended ways?
Can this be used in conjunction with other scripts in a negative manner?
Will any transactions be adequately logged?

By adequately asking these questions while writing the script, rather than later, you prevent an unfortunate re-write when you need to increase your security. By starting out with this mindset, you won't guarantee the security of your system, but you can help improve it.

You may also want to consider turning off register_globals, magic_quotes, or other convenience settings which may confuse you as to the validity, source, or value of a given variable. Working with PHP in error_reporting(E_ALL) mode can also help warn you about variables being used before they are checked or initialized (so you can prevent unusual data from being operated upon).

Hiding PHP

In general, security by obscurity is one of the weakest forms of security. But in some cases, every little bit of extra security is desirable.

A few simple techniques can help to hide PHP, possibly slowing down an attacker who is attempting to discover weaknesses in your system. By setting expose_php = off in your php.ini file, you reduce the amount of information available to them.

Another tactic is to configure web servers such as apache to parse different filetypes through PHP, either with an .htaccess directive, or in the apache configuration file itself. You can then use misleading file extensions:

Příklad 5-18. Hiding PHP as another language

# Make PHP code look like other code types AddType application/x-httpd-php .asp .py .pl
Or obscure it completely:

Příklad 5-19. Using unknown types for PHP extensions

# Make PHP code look like unknown types AddType application/x-httpd-php .bop .foo .133t
Or hide it as html code, which has a slight performance hit because all html will be parsed through the PHP engine:

Příklad 5-20. Using html types for PHP extensions

# Make all PHP code look like html AddType application/x-httpd-php .htm .html
For this to work effectively, you must rename your PHP files with the above extensions. While it is a form of security through obscurity, it's a minor preventative measure with few drawbacks.

Keeping Current

PHP, like any other large system, is under constant scrutiny and improvement. Each new version will often include both major and minor changes to enhance and repair security flaws, configuration mishaps, and other issues that will affect the overall security and stability of your system.

Like other system-level scripting languages and programs, the best approach is to update often, and maintain awareness of the latest versions and their changes.

II. Reference jazyka

Obsah
6. Základní syntaxe
7. Types
8. Proměnné
9. Konstanty
10. Výrazy
11. Operátory
12. Řídicí struktury
13. Funkce
14. Classes and Objects
15. Vysvětlení referencí (odkazů)

Kapitola 6. Základní syntaxe

Opuštění HTML

Jsou čtyři způsoby jak opustit HTML a vstoupit to "PHP módu":

Příklad 6-1. Způsoby opuštění HTML

1. <? echo ("toto je nejjednodušší SGML zpracovatelská instrukce\n"); ?> 2. <?php echo("pokud chcete zpracovávat XHTML nebo XML dokumenty, používejte toto\n"); ?> 3. <script language="php"> echo ("některé editory (například FrontPage) nemají zpracovatelské instrukce v lásce"); </script> 4. <% echo ("případně můžete používat ASP tagy"); %> <%= $variable; # toto je zkratka za "<%echo .." %>

První způsob je dostupný pouze, pokud jsou povoleny krátké tagy. To se dá udělat povolením konfigurační direktivy short_open_tag v konfiguračním souboru PHP, nebo kompilací PHP s configure volbou --enable-short-tags.

Obecně preferovanou metodou je druhý způsob, protože umožňuje snadnou implementaci dalšího generování XHTML z PHP.

Čtvrtý způsob je dostupný, pouze pokud byly povoleny ASP tagy pomocí konfigurační direktivy asp_tags.

Poznámka: Podpora ASP tagů byla přidána v 3.0.4.

Případná bezprostředně následující sekvence konce řádku je součástí uzavírajícího tagu.

Oddělování instrukcí

Instrukce se oddělují stejně jako v C nebo Perlu - ukončujte každý výraz středníkem.

Uzavírající tag (?>) také implikuje konec výrazu, takže následující ukázky jsou ekvivalentní:

<?php
    echo "Toto je test";
?>

<?php echo "Toto je test" ?>

Komentáře

PHP podporuje komentářové notace jazyků 'C', 'C++' a Unixového shellu. Například:

<?php
    echo "Toto je test"; // Toto je jednořádkový komentář typu C++
    /* Toto je víceřádkový komentář
       a ještě jeden komentář */
    echo "Toto je další test";
    echo "Poslední Test"; # Toto je komentář shellového typu
?>

Jednořádkové typy komentářů ve skutečnosti komentují do konce řádku nebo současného bloku PHP kódu, podle toho, co se vyskytuje dřív.

<h1>Toto je  <?php # echo "malý";?> příklad.</h1>
<p>Hlavička na předchozím řádku bude 'Toto je příklad'.

Měli byste si dát pozor na vnořování komentářů typu 'C++', ke kterému může dojít při zakomentování velkých bloků.

<?php
 /*
    echo "Toto je test"; /* Tento komentář způsobí problém */
 */
?>

Kapitola 7. Types

Introduction

PHP supports eight primitive types.

Four scalar types:

Two compound types:

array
object

And finally two special types:

Poznámka: In this manual you'll often find mixed parameters. This pseudo-type indicates multiple possibilities for that parameter.

The type of a variable is usually not set by the programmer; rather, it is decided at runtime by PHP depending on the context in which that variable is used.

Poznámka: If you want to check out the type and value of a certain expression, use var_dump().

If you simply want a human-readable representation of the type for debugging, use gettype(). To check for a certain type, do not use gettype(), but use the is_type functions.

If you would like to force a variable to be converted to a certain type, you may either cast the variable or use the settype() function on it.

Note that a variable may behave in different manners in certain situations, depending on what type it is at the time. For more information, see the section on Type Juggling.

Booleans

This is the easiest type. A boolean expresses a truth value. It can be either TRUE or FALSE.

Poznámka: The boolean type was introduced in PHP 4.

Syntax

To specify a boolean literal, use either the keyword TRUE or FALSE. Both are case-insensitive.

$foo = True; // assign the value TRUE to $foo

Usually you use some kind of operator which returns a boolean value, and then pass it on to a control structure.

// == is an operator which returns a boolean
if ($action == "show_version") {
    echo "The version is 1.23";
}

// this is not necessary:
if ($show_separators == TRUE) {
    echo "<hr>\n";
}

// because you can simply type this:
if ($show_separators) {
    echo "<hr>\n";
}

Converting to boolean

To explicitly convert a value to boolean, use either the (bool) or the (boolean) cast. However, in most cases you do not need to use the cast, since a value will be automatically converted if an operator, function or control structure requires a boolean argument.

Integers

An integer is a number of the set Z = {..., -2, -1, 0, 1, 2, ...}.

Syntax

Integers can be specified in decimal (10-based), hexadecimal (16-based) or octal (8-based) notation, optionally preceded by a sign (- or +).

If you use the octal notation, you must precede the number with a 0 (zero), to use hexadecimal notation precede the number with 0x.

Příklad 7-1. Integer literals

$a = 1234; # decimal number $a = -123; # a negative number $a = 0123; # octal number (equivalent to 83 decimal) $a = 0x1A; # hexadecimal number (equivalent to 26 decimal)
The size of an integer is platform-dependent, although a maximum value of about two billion is the usual value (that's 32 bits signed). PHP does not support unsigned integers.

Integer overflow

If you specify a number beyond the bounds of the integer type, it will be interpreted as a float instead. Also, if you perform an operation that results in a number beyond the bounds of the integer type, a float will be returned instead.

$large_number =  2147483647;
var_dump($large_number);
// output: int(2147483647)

$large_number =  2147483648;
var_dump($large_number);
// output: float(2147483648)

// this goes also for hexadecimal specified integers:
var_dump( 0x80000000 );
// output: float(2147483648)

$million = 1000000;
$large_number =  50000 * $million;
var_dump($large_number);
// output: float(50000000000)

Varování

Unfortunately, there was a bug in PHP so that this does not always work correctly when there are negative numbers involved. For example: when you do -50000 * $million, the result will be -429496728. However, when both operands are positive there is no problem.

This is solved in PHP 4.1.0.

There is no integer division operator in PHP. 1/2 yields the float 0.5.

var_dump( 25/7 );
// output: float(3.5714285714286)

Converting to integer

To explicitly convert a value to integer, use either the (int) or the (integer) cast. However, in most cases you do not need to use the cast, since a value will be automatically converted if an operator, function or control structure requires a integer argument.

From booleans

FALSE will yield 0 (zero), and TRUE will yield 1 (one).

From floating point numbers

When converting from float to integer, the number will be rounded towards zero.

If the float is beyond the boundaries of integer (usually +/- 2.15e+9 = 2^31), the result is undefined, since the float hasn't got enough precision to give an exact integer result. No warning, not even a notice will be issued in this case!

Varování

Never cast an unknown fraction to integer, as this can sometimes lead to unexpected results.

echo (int) ( (0.1+0.7) * 10 ); // echoes 7!

See for more information the warning about float-precision.

From strings

See String conversion

From other types

Výstraha

Behaviour of converting to integer is undefined for other types. Currently, the behaviour is the same as if the value was first converted to boolean. However, do not rely on this behaviour, as it can change without notice.

Floating point numbers

Floating point numbers (AKA "floats", "doubles" or "real numbers") can be specified using any of the following syntaxes:

$a = 1.234; $a = 1.2e3; $a = 7E-10;
The size of a float is platform-dependent, although a maximum of ~1.8e308 with a precision of roughly 14 decimal digits is a common value (that's 64 bit IEEE format).

Floating point precision

It is quite usual that simple decimal fractions like 0.1 or 0.7 cannot be converted into their internal binary counterparts without a little loss of precision. This can lead to confusing results: for example, floor((0.1+0.7)*10) will usually return 7 instead of the expected 8 as the result of the internal representation really being something like 7.9999999999....

This is related to the fact that it is impossible to exactly express some fractions in decimal notation with a finite number of digits. For instance, 1/3 in decimal form becomes 0.3333333. . ..

So never trust floating number results to the last digit and never compare floating point numbers for equality. If you really need higher precision, you should use the arbitrary precision math functions or gmp functions instead.

Strings

A string is series of characters. In PHP, a character is the same as a byte, that is, there are exactly 256 different characters possible. This also implies that PHP has no native support of Unicode.

Poznámka: It is no problem for a string to become very large. There is no practical bound to the size of strings imposed by PHP, so there is no reason at all to worry about long strings.

Syntax

A string literal can be specified in three different ways.

Single quoted

The easiest way to specify a simple string is to enclose it in single quotes (the character ').

To specify a literal single quote, you will need to escape it with a backslash (\), like in many other languages. If a backslash needs to occur before a single quote or at the end of the string, you need to double it. Note that if you try to escape any other character, the backslash too will be printed! So usually there is no need to escape the backslash itself.

Poznámka: In PHP 3, a warning will be issued at the E_NOTICE level when this happens.

Poznámka: Unlike the two other syntaxes, variables will not be expanded when they occur in single quoted strings.

echo 'this is a simple string';
echo 'You can also have embedded newlines in strings,
like this way.';
echo 'Arnold once said: "I\'ll be back"';
// output: ... "I'll be back"
echo 'Are you sure you want to delete C:\\*.*?';
// output: ... delete C:\*.*?
echo 'Are you sure you want to delete C:\*.*?';
// output: ... delete C:\*.*?
echo 'I am trying to include at this point: \n a newline';
// output: ... this point: \n a newline

Double quoted

If the string is enclosed in double-quotes ("), PHP understands more escape sequences for special characters:

Tabulka 7-1. Escaped characters

sequence	meaning
`\n`	linefeed (LF or 0x0A (10) in ASCII)
`\r`	carriage return (CR or 0x0D (13) in ASCII)
`\t`	horizontal tab (HT or 0x09 (9) in ASCII)
`\\`	backslash
`\$`	dollar sign
`\"`	double-quote
`\[0-7]{1,3}`	the sequence of characters matching the regular expression is a character in octal notation
`\x[0-9A-Fa-f]{1,2}`	the sequence of characters matching the regular expression is a character in hexadecimal notation

Again, if you try to escape any other character, the backslash will be printed too!

But the most important pre of double-quoted strings is the fact that variable names will be expanded. See string parsing for details.

Heredoc

Another way to delimit strings is by using heredoc syntax ("<<<"). One should provide an identifier after <<<, then the string, and then the same identifier to close the quotation.

The closing identifier must begin in the first column of the line. Also, the identifier used must follow the same naming rules as any other label in PHP: it must contain only alphanumeric characters and underscores, and must start with a non-digit character or underscore.

Varování

It is very important to note that the line with the closing identifier contains no other characters, except possibly a semicolon (;). That means especially that the identifier may not be indented, and there may not be any spaces or tabs after or before the semicolon.

Probably the nastiest gotcha is that there may also not be a carriage return (\r) at the end of the line, only a form feed, AKA newline (\n). Since Microsoft Windows uses the sequence \r\n as a line terminator, your heredoc may not work if you write your script in a Windows editor. However, most programming editors provide a way to save your files with a UNIX line terminator.

Heredoc text behaves just like a double-quoted string, without the double-quotes. This means that you do not need to escape quotes in your here docs, but you can still use the escape codes listed above. Variables are expanded, but the same care must be taken when expressing complex variables inside a here doc as with strings.

Příklad 7-2. Heredoc string quoting example

<?php $str = <<<EOD Example of string spanning multiple lines using heredoc syntax. EOD; /* More complex example, with variables. */ class foo { var $foo; var $bar; function foo() { $this->foo = 'Foo'; $this->bar = array('Bar1', 'Bar2', 'Bar3'); } } $foo = new foo(); $name = 'MyName'; echo <<<EOT My name is "$name". I am printing some $foo->foo. Now, I am printing some {$foo->bar[1]}. This should print a capital 'A': \x41 EOT; ?>

Poznámka: Heredoc support was added in PHP 4.

Variable parsing

When a string is specified in double quotes or with heredoc, variables are parsed within it.

There are two types of syntax, a simple one and a complex one. The simple syntax is the most common and convenient, it provides a way to parse a variable, an array value, or an object property.

The complex syntax was introduced in PHP 4, and can by recognised by the curly braces surrounding the expression.

Simple syntax

If a dollar sign ($) is encountered, the parser will greedily take as much tokens as possible to form a valid variable name. Enclose the variable name in curly braces if you want to explicitly specify the end of the name.

$beer = 'Heineken';
echo "$beer's taste is great"; // works, "'" is an invalid character for varnames
echo "He drunk some $beers"; // won't work, 's' is a valid character for varnames
echo "He drunk some ${beer}s"; // works

Similarly, you can also have an array index or an object property parsed. With array indices, the closing square bracket (]) marks the end of the index. For object properties the same rules apply as to simple variables, though with object properties there doesn't exist a trick like the one with variables.

$fruits = array( 'strawberry' => 'red' , 'banana' => 'yellow' );

// note that this works differently outside string-quotes.
echo "A banana is $fruits[banana].";

echo "This square is $square->width meters broad.";

// Won't work. For a solution, see the complex syntax.
echo "This square is $square->width00 centimeters broad.";

For anything more complex, you should use the complex syntax.

Complex (curly) syntax

This isn't called complex because the syntax is complex, but because you can include complex expressions this way.

In fact, you can include any value that is in the namespace in strings with this syntax. You simply write the expression the same way as you would outside the string, and then include it in { and }. Since you can't escape '{', this syntax will only be recognised when the $ is immediately following the {. (Use "{\$" or "\{$" to get a literal "{$"). Some examples to make it clear:

$great = 'fantastic';
echo "This is { $great}"; // won't work, outputs: This is { fantastic}
echo "This is {$great}";  // works, outputs: This is fantastic
echo "This square is {$square->width}00 centimeters broad."; 
echo "This works: {$arr[4][3]}";     

// This is wrong for the same reason
// as $foo[bar] is wrong outside a string. 
echo "This is wrong: {$arr[foo][3]}"; 

echo "You should do it this way: {$arr['foo'][3]}";
echo "You can even write {$obj->values[3]->name}";
echo "This is the value of the var named $name: {${$name}}";

String access by character

Characters within strings may be accessed by specifying the zero-based offset of the desired character after the string in curly braces.

Poznámka: For backwards compatibility, you can still use the array-braces. However, this syntax is deprecated as of PHP 4.

Příklad 7-3. Some string examples

<?php /* Assigning a string. */ $str = "This is a string"; /* Appending to it. */ $str = $str . " with some more text"; /* Another way to append, includes an escaped newline. */ $str .= " and a newline at the end.\n"; /* This string will end up being '<p>Number: 9</p>' */ $num = 9; $str = "<p>Number: $num</p>"; /* This one will be '<p>Number: $num</p>' */ $num = 9; $str = '<p>Number: $num</p>'; /* Get the first character of a string */ $str = 'This is a test.'; $first = $str{0}; /* Get the last character of a string. */ $str = 'This is still a test.'; $last = $str{strlen($str)-1}; ?>

Useful functions

Strings may be concatenated using the '.' (dot) operator. Note that the '+' (addition) operator will not work for this. Please see String operators for more information.

There are a lot of useful functions for string modification.

See the string functions section for general functions, the regular expression functions for advanced find&replacing (in two tastes: Perl and POSIX extended).

There are also functions for URL-strings, and functions to encrypt/decrypt strings (mcrypt and mhash).

Finally, if you still didn't find what you're looking for, see also the character type functions.

String conversion

When a string is evaluated as a numeric value, the resulting value and type are determined as follows.

The string will evaluate as a float if it contains any of the characters '.', 'e', or 'E'. Otherwise, it will evaluate as an integer.

The value is given by the initial portion of the string. If the string starts with valid numeric data, this will be the value used. Otherwise, the value will be 0 (zero). Valid numeric data is an optional sign, followed by one or more digits (optionally containing a decimal point), followed by an optional exponent. The exponent is an 'e' or 'E' followed by one or more digits.

$foo = 1 + "10.5";              // $foo is float (11.5)
$foo = 1 + "-1.3e3";            // $foo is float (-1299)
$foo = 1 + "bob-1.3e3";         // $foo is integer (1)
$foo = 1 + "bob3";              // $foo is integer (1)
$foo = 1 + "10 Small Pigs";     // $foo is integer (11)
$foo = 4 + "10.2 Little Piggies"; // $foo is float (14.2)
$foo = "10.0 pigs " + 1;        // $foo is float (11)
$foo = "10.0 pigs " + 1.0;      // $foo is float (11)

For more information on this conversion, see the Unix manual page for strtod(3).

If you would like to test any of the examples in this section, you can cut and paste the examples and insert the following line to see for yourself what's going on:

echo "\$foo==$foo; type is " . gettype ($foo) . "<br />\n";

Arrays

An array in PHP is actually an ordered map. A map is a type that maps values to keys. This type is optimized in several ways, so you can use it as a real array, or a list (vector), hashtable (which is an implementation of a map), dictionary, collection, stack, queue and probably more. Because you can have another PHP-array as a value, you can also quite easily simulate trees.

Explanation of those structures is beyond the scope of this manual, but you'll find at least one example for each of those structures. For more information about those structures, we refer you to external literature about this broad topic.

Syntax

Specifying with array()

An array can be created by the array() language-construct. It takes a certain number of comma-separated key => value pairs.

A key is either an integer or a string. If a key is the standard representation of an integer, it will be interpreted as such (i.e. "8" will be interpreted as 8, while "08" will be interpreted as "08").

A value can be anything.

If you omit a key, the maximum of the integer-indices is taken, and the new key will be that maximum + 1. As integers can be negative, this is also true for negative indices. Having e.g. the highest index being -6 will result in being -5 the new key. If no integer-indices exist yet, the key will be 0 (zero). If you specify a key that already has a value assigned to it, that value will be overwritten.

Using true as a key will evalute to integer 1 as key. Using false as a key will evalute to integer 0 as key. Using NULL as a key will evalute to an empty string. Using an emptry string as key will create (or overwrite) a key with an empty string and its value, it is not the same as using empty brackets.

You cannot use arrays or objects as keys. Doing so will result in a warning: Illegal offset type.

array( [key =>] value , ... ) // key is either string or nonnegative integer // value can be anything

Creating/modifying with square-bracket syntax

You can also modify an existing array, by explicitly setting values.

This is done by assigning values to the array while specifying the key in brackets. You can also omit the key, add an empty pair of brackets ("[]") to the variable-name in that case.

$arr[key] = value; $arr[] = value; // key is either string or nonnegative integer // value can be anything
If $arr doesn't exist yet, it will be created. So this is also an alternative way to specify an array. To change a certain value, just assign a new value to it. If you want to remove a key/value pair, you need to unset() it.

Useful functions

There are quite some useful function for working with arrays, see the array-functions section.

Poznámka: The unset() function allows unsetting keys of an array. Be aware that the array will NOT be reindexed.
$a = array( 1 => 'one', 2 => 'two', 3 => 'three' );
unset( $a[2] );
/* will produce an array that would have been defined as
   $a = array( 1=>'one', 3=>'three');
   and NOT
   $a = array( 1 => 'one', 2 => 'three');
*/

The foreach control structure exists specificly for arrays. It provides an easy way to traverse an array.

Array do's and don'ts

Why is `$foo[bar]` wrong?

You should always use quotes around an associative array index. For example, use $foo['bar'] and not $foo[bar]. But why is $foo[bar] wrong? You might have seen the following syntax in old scripts:

$foo[bar] = 'enemy';
echo $foo[bar];
// etc

This is wrong, but it works. Then, why is it wrong? The reason is that this code has an undefined constant (bar) rather than a string ('bar' - notice the quotes), and PHP may in future define constants which, unfortunately for your code, have the same name. It works, because the undefined constant gets converted to a string of the same name.

As stated in the syntax section, there must be an expression between the square brackets ('[' and ']'). That means that you can write things like this:

echo $arr[ foo(true) ];

This is an example of using a function return value as the array index. PHP knows also about constants, and you may have seen the E_* before.

$error_descriptions[E_ERROR] = "A fatal error has occured";
$error_descriptions[E_WARNING] = "PHP issued a warning";
$error_descriptions[E_NOTICE] = "This is just an informal notice";

Note that E_ERROR is also a valid identifier, just like bar in the first example. But the last example is in fact the same as writing:

$error_descriptions[1] = "A fatal error has occured";
$error_descriptions[2] = "PHP issued a warning";
$error_descriptions[8] = "This is just an informal notice";

because E_ERROR equals 1, etc.

Then, how is it possible that $foo[bar] works? It works, because bar is due to its syntax expected to be a constant expression. However, in this case no constant with the name bar exists. PHP now assumes that you meant bar literally, as the string "bar", but that you forgot to write the quotes.

So why is it bad then?

At some point in the future, the PHP team might want to add another constant or keyword, and then you get in trouble. For example, you already cannot use the words empty and default this way, since they are special reserved keywords.

Poznámka: When you turn error_reporting to E_ALL, you will see that PHP generates notices whenever an index is used which is not defined (put the line error_reporting(E_ALL); in your script).

Poznámka: Inside a double-quoted string, an other syntax is valid. See variable parsing in strings for more details.

Examples

The array type in PHP is very versatile, so here will be some examples to show you the full power of arrays.

// this
$a = array( 'color' => 'red'
          , 'taste' => 'sweet'
          , 'shape' => 'round'
          , 'name'  => 'apple'
          ,            4        // key will be 0
          );

// is completely equivalent with
$a['color'] = 'red';
$a['taste'] = 'sweet';
$a['shape'] = 'round';
$a['name'] = 'apple';
$a[]        = 4;        // key will be 0

$b[] = 'a';
$b[] = 'b';
$b[] = 'c';
// will result in the array array( 0 => 'a' , 1 => 'b' , 2 => 'c' ),
// or simply array('a', 'b', 'c')

Příklad 7-4. Using array()

// Array as (property-)map
$map = array( 'version'    => 4
            , 'OS'         => 'Linux'
            , 'lang'       => 'english'
            , 'short_tags' => true
            );
            
// strictly numerical keys
$array = array( 7
              , 8
              , 0
              , 156
              , -10
              );
// this is the same as array( 0 => 7, 1 => 8, ...)

$switching = array(         10 // key = 0
                  , 5    =>  6
                  , 3    =>  7 
                  , 'a'  =>  4
                  ,         11 // key = 6 (maximum of integer-indices was 5)
                  , '8'  =>  2 // key = 8 (integer!)
                  , '02' => 77 // key = '02'
                  , 0    => 12 // the value 10 will be overwritten by 12
                  );
                  
// empty array
$empty = array();

Příklad 7-5. Collection

$colors = array('red','blue','green','yellow');

foreach ( $colors as $color ) {
    echo "Do you like $color?\n";
}

/* output:
Do you like red?
Do you like blue?
Do you like green?
Do you like yellow?
*/

Note that it is currently not possible to change the values of the array directly in such a loop. A workaround is the following:

Příklad 7-6. Collection

foreach ($colors as $key => $color) { // won't work: //$color = strtoupper($color); //works: $colors[$key] = strtoupper($color); } print_r($colors); /* output: Array ( [0] => RED [1] => BLUE [2] => GREEN [3] => YELLOW ) */

This example creates a one-based array.

Příklad 7-7. One-based index

$firstquarter = array(1 => 'January', 'February', 'March'); print_r($firstquarter); /* output: Array ( [1] => 'January' [2] => 'February' [3] => 'March' ) */

Příklad 7-8. Filling real array

// fill an array with all items from a directory
$handle = opendir('.');
while ($file = readdir($handle)) 
{
    $files[] = $file;
}
closedir($handle);

Arrays are ordered. You can also change the order using various sorting-functions. See array-functions for more information.

Příklad 7-9. Sorting array

sort($files);
print_r($files);

Because the value of an array can be everything, it can also be another array. This way you can make recursive and multi-dimensional arrays.

Příklad 7-10. Recursive and multi-dimensional arrays

$fruits = array ( "fruits"  => array ( "a" => "orange"
                                     , "b" => "banana"
                                     , "c" => "apple"
                                     )
                , "numbers" => array ( 1
                                     , 2
                                     , 3
                                     , 4
                                     , 5
                                     , 6
                                     )
                , "holes"   => array (      "first"
                                     , 5 => "second"
                                     ,      "third"
                                     )
                );

Objects

Object Initialization

To initialize an object, you use the new statement to instantiate the object to a variable.

<?php
class foo
{
    function do_foo()
    {
        echo "Doing foo."; 
    }
}

$bar = new foo;
$bar->do_foo();
?>

For a full discussion, please read the section Classes and Objects.

Resource

A resource is a special variable, holding a reference to an external resource. Resources are created and used by special functions. See the appendix for a listing of all these functions and the corresponding resource types.

Poznámka: The resource type was introduced in PHP 4

Freeing resources

Due to the reference-counting system introduced with PHP4's Zend-engine, it is automatically detected when a resource is no longer referred to (just like Java). When this is the case, all resources that were in use for this resource are made free by the garbage collector. For this reason, it is rarely ever necessary to free the memory manually by using some free_result function.

Poznámka: Persistent database-links are special, they are not destroyed by the gc. See also persistent links

NULL

The special NULL value represents that a variable has no value. NULL is the only possible value of type NULL.

Poznámka: The null type was introduced in PHP 4

A variable is considered to be NULL if

it has been assigned the constant NULL.
it has not been set to any value yet.
it has been unset().

Syntax

There is only one value of type NULL, and that is the case-insensitive keyword NULL.

$var = NULL;

Type Juggling

PHP does not require (or support) explicit type definition in variable declaration; a variable's type is determined by the context in which that variable is used. That is to say, if you assign a string value to variable var, var becomes a string. If you then assign an integer value to var, it becomes an integer.

An example of PHP's automatic type conversion is the addition operator '+'. If any of the operands is a float, then all operands are evaluated as floats, and the result will be a float. Otherwise, the operands will be interpreted as integers, and the result will also be an integer. Note that this does NOT change the types of the operands themselves; the only change is in how the operands are evaluated.

$foo = "0";  // $foo is string (ASCII 48)

$foo += 2;   // $foo is now an integer (2)
$foo = $foo + 1.3;  // $foo is now a float (3.3)
$foo = 5 + "10 Little Piggies"; // $foo is integer (15)
$foo = 5 + "10 Small Pigs";     // $foo is integer (15)

If the last two examples above seem odd, see String conversion.

If you wish to force a variable to be evaluated as a certain type, see the section on Type casting. If you wish to change the type of a variable, see settype().

If you would like to test any of the examples in this section, you can use the var_dump() function.

Poznámka: The behaviour of an automatic conversion to array is currently undefined.
$a = 1;       // $a is an integer
$a[0] = "f";  // $a becomes an array, with $a[0] holding "f"
While the above example may seem like it should clearly result in $a becoming an array, the first element of which is 'f', consider this:
$a = "1";     // $a is a string
$a[0] = "f";  // What about string offsets? What happens?
Since PHP supports indexing into strings via offsets using the same syntax as array indexing, the example above leads to a problem: should $a become an array with its first element being "f", or should "f" become the first character of the string $a?

For this reason, as of PHP 3.0.12 and PHP 4.0b3-RC4, the result of this automatic conversion is considered to be undefined. Fixes are, however, being discussed.

Type Casting

Type casting in PHP works much as it does in C: the name of the desired type is written in parentheses before the variable which is to be cast.

$foo = 10;   // $foo is an integer
$bar = (float) $foo;   // $bar is a float

The casts allowed are:

(int), (integer) - cast to integer
(bool), (boolean) - cast to boolean
(float), (double), (real) - cast to float
(string) - cast to string
(array) - cast to array
(object) - cast to object

Poznámka: Instead of casting a variable to string, you can also enclose the variable in double quotes.

Note that tabs and spaces are allowed inside the parentheses, so the following are functionally equivalent:

$foo = (int) $bar;
$foo = ( int ) $bar;

It may not be obvious exactly what will happen when casting between certain types. For more info, see these sections:

When casting or forcing a conversion from array to string, the result will be the word Array. When casting or forcing a conversion from object to string, the result will be the word Object.

When casting from a scalar or a string variable to an array, the variable will become the first element of the array:

$var = 'ciao';
$arr = (array) $var;
echo $arr[0];  // outputs 'ciao'

When casting from a scalar or a string variable to an object, the variable will become an attribute of the object; the attribute name will be 'scalar':

$var = 'ciao';
$obj = (object) $var;
echo $obj->scalar;  // outputs 'ciao'

Kapitola 8. Proměnné

Základy

Proměnné jsou v PHP reprezentovány znakem dolaru, následovaným názvem příslušné proměnné. V názvech proměnných se rozlišuje velikost písmen.

Názvy proměnných jsou podřízeny stejným pravidlům jako jiná návěští v PHP. Platný název proměnné začíná písmenem nebo podtržítkem, následovaným libovolným počtem písmen, číslic nebo potržítek. Jako regulární výraz to lze zapsat takto: '[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*'

Poznámka: Pro naše účely zde budeme za písmena považovat znaky a-z, A-Z a ASCII znaky od 127 do 255 (0x7f-0xff).

$var = "Bob";
$Var = "Joe";
echo "$var, $Var";      // vypíše "Bob, Joe"

$4site = 'not yet';     // neplatné; začíná číslicí
$_4site = 'not yet';    // platné; začíná podtržítkem
$täyte = 'mansikka';    // platné; 'ä' je ASCII 228.

V PHP 3 mají proměnné vždy přiřazenu hodnotu. To znamená, že když přiřadíte výraz do proměnné, celá hodnota původního výrazu se zkopíruje do cílové proměnné. Tedy, například, po přiřazení hodnoty jedné proměnné do druhé, změna jedné z nich se na druhé neprojeví. Více informací o tomto způsobu přiřazení viz Výrazy.

PHP nabízí jiný způsob přiřazení hodnot proměnným: přiřazení odkazu. To znamená, že nová proměnná jednoduše odkazuje (jinými slovy, "stává se aliasem" nebo "ukazuje na") na původní proměnnou. Změny na nové proměnné se projeví na té původní a naopak. To také znamená, že se nic nekopíruje; proto je přiřazení rychlejší. Avšak toto zrychlení bude zjistitelné pouze v těsných cyklech nebo při přiřazování velkých polí či objektů.

Pro přiřazení odkazu stačí jednoduše před proměnnou, která bude přiřazována (zdrojová proměnná), předřadit ampersand (&). Například následující kus kódu vypíše dvakrát 'Jmenuji se Bob':

<?php
$foo = 'Bob';              // Přiřadí hodnotu 'Bob' do $foo
$bar = &$foo;              // Odkaz $foo přes $bar.
$bar = "Jmenuji se $bar";  // Změna $bar...
echo $bar;
echo $foo;                 // $foo je také změněno.
?>

Jednou z důležitých věcí, které je třeba si uvědomit, je to, že přes odkazy lze přiřazovat pouze pojmenované proměnné.

<?php
$foo = 25;
$bar = &$foo;      // Toto je platné přiřazení.
$bar = &(24 * 7);  // Neplatné; odkazuje se nepojmenovaný výraz.

function test()
{
   return 25;
}

$bar = &test();    // Neplatné.
?>

Předdefinované proměnné

PHP poskytuje velké množství předdefinovaných proměnných jakémukoli skriptu, který provádí. Mnoho těchto proměnných, bohužel, nemůže být plně zdokumentováno, protože závisejí na tom, na kterém serveru skript běží, na verzi a nastavení serveru a dalších faktorech. Některé z těchto proměnných nebudou dostupné, když PHP poběží z příkazové řádky. Seznam proměnných - viz sekce Předdefinované proměnné.

Varování

V PHP 4.2.0 a pozdějších se změnila implicitní sada předdefinovaných proměnných, které jsou globálně dostupné. Individuální vstupní a serverové proměnné se implicitně neumísťují do globálního kontextu; namísto toho jsou v následujících superglobálních polích.

Můžete však stále vynutit staré chování nastavením register_globals v souboru php.ini na 'On'.

Pro více informací a pozadí těchto změn prosím nahlédněte do PHP 4.1.0 Release Announcement.

Od verze 4.1.0 poskytuje PHP sadu předdefinovaných polí, obsahujících proměnné WWW serveru (pokud to jde), prostředí a uživatelského vstupu. Tato nová pole mají tu zvláštnost, že jsou automaticky globální -- tedy např. automaticky dostupné v každém kontextu. Z tohoto důvodu jsou často známa jako "autoglobální" nebo "superglobální". (V PHP neexistuje mechanismus pro uživatelskou definici superglobálních proměnných). Superglobální proměnné jsou vypsány níže; pro seznam jejich obsahů a další diskusi o předdefinovaných proměnných v PHP a jejich charakteru však musíte nahlédnout do části Předdefinované proměnné.

PHP superglobals (superglobální proměnné)

$GLOBALS: Obsahuje odkaz na každou proměnnou, která je momentálně dostupná v globálním kontextu skriptu. Klíči tohoto pole jsou názvy globálních proměnných.
$_SERVER: Proměnné nastavované WWW serveru nebo jinak přímo spjaté s prováděcím prostředím aktuálního skriptu. Analogické starému poli $HTTP_SERVER_VARS (které je stále dostupné, ale zavržené).
$_GET: Proměnné poskytované skriptu přes HTTP GET. Analogické starému poli $HTTP_GET_VARS (které je stále dostupné, ale zavržené).
$_POST: Proměnné poskytované skriptu přes HTTP POST. Analogické starému poli $HTTP_POST_VARS (které je stále dostupné, ale zavržené).
$_COOKIE: Proměnné poskytované skriptu přes HTTP cookies. Analogické starému poli $HTTP_COOKIE_VARS (které je stále dostupné, ale zavržené).
$_FILES: Proměnné poskytované skriptu přes HTTP post uploady souborů. Analogické uploads. Analogické starému poli $HTTP_POST_FILES (které je stále dostupné, ale zavržené). Více informací - viz Upload metodou POST.
$_ENV: Proměnné poskytované skriptu z prostředí. Analogické starému poli $HTTP_ENV_VARS (které je stále dostupné, ale zavržené).
$_REQUEST: Proměnné poskytované skriptu přes libovolný vstupní mechanismus a kterým proto nelze důvěřovat. Pozn.: při běhu z příkazové řádky zde nebudou přítomny položky argv a argc; nacházejí se v poli $_SERVER. Přítomnost a pořadí proměnných v tomto poli se definuje podle konfigurační direktivy variables_order. Toto pole nemá přímou analogii ve verzích PHP před 4.1.0.
$_SESSION: Proměnné, které jsou momentálně registrovány v aktuální relaci skriptu. Analogické starému poli $HTTP_SESSION_VARS (které je stále dostupné, ale zavržené). Více informací - viz Funkce pro obsluhu sessions.

Kontext ("scope") proměnné

Kontext proměnné je oblast, ve které je definována. Většina proměnných v PHP má pouze jediný kontext. Ten zahrnuje i soubory vložené pomocí "include" nebo "require". Například:

$a = 1;
include "b.inc";

Zde bude proměnná $a dostupná ve vloženém skriptu b.inc. Avšak uvnitř uživatelsky definovaných funkcí se zakládá jejich lokální kontext. Jakákoli proměnná použitá uvnitř funkce je implicitně omezena na tento místní kontext. Například:

$a = 1; /* globální kontext */ 

function Test()
{ 
    echo $a; /* odkaz na proměnnou v lokálním kontextu */ 
} 

Test();

Tento skript nevyprodukuje žádný výstup, protože konstrukt "echo" odkazuje na lokální verzi proměnné $a, a ta nemá v tomto kontextu přiřazenu žádnou hodnotu. Můžete si všimnout, že to je trochu jiné než v jazyce C, kde jsou globální funkce automaticky dostupné ve funkcích, pokud nejsou specificky zastíněny lokální definicí. To může způsobit problémy tím, že člověk může nechtěně změnit globální proměnnou. V PHP musí být globální proměnné deklarovány uvnitř funkce jako globální, pokud se v ní mají používat. Příklad:

$a = 1;
$b = 2;

function Sum()
{
    global $a, $b;

    $b = $a + $b;
} 

Sum();
echo $b;

Výše uvedený skript vytiskne "3". Deklarací $a a $b ve funkci jako globálních proměnných se dosáhne toho, že při odkazování na proměnné se pracuje s jejich globální verzí. Počet globálních proměnných, se kterými lze ve funkci manipulovat, není omezen.

Druhým způsobem, jak přistupovat k proměnným z globálního kontextu, je použití speciálního pole $GLOBALS, definovaného v PHP. Předchozí příklad lze přepsat:

$a = 1;
$b = 2;

function Sum()
{
    $GLOBALS["b"] = $GLOBALS["a"] + $GLOBALS["b"];
} 

Sum();
echo $b;

Pole $GLOBALS je asociativní pole s názvem globální proměnné jako klíčem a obsahem příslušné proměnné jako obsahem elementu pole.

Jinou důležitou vlastností rozlišování kontextů proměnných je možnost používání static proměnných. Statická proměnná existuje pouze v lokálním kontextu funkce, ale neztrácí svoji hodnotu, pokud provádění programu tento kontext opustí. Uvažujme následující příklad:

function Test ()
{
    $a = 0;
    echo $a;
    $a++;
}

Tato funkce je poněkud neužitečná, neboť při každém volání nastavuje $a na 0 a tiskne "0". Konstrukt $a++, který inkrementuje proměnnou, nemá žádný význam, protože při skončení vykonávání funkce se obsah proměnné $a ztrácí. Aby měla funkce skutečný význam čítače a hodnota se neztrácela, deklaruje se proměnná $a jako statická:

function Test()
{
    static $a = 0;
    echo $a;
    $a++;
}

Nyní se při každém volání funkce Test() vytiskne hodnota proměnné $a a inkrementuje se.

Statické proměnné také poskytují způsob, jak řešit rekurzívní funkce. Rekurzívní funkce je taková funkce, která volá sama sebe. Psaní rekurzívních funkcí je třeba věnovat zvláštní péči, protože může vzniknout nekonečný cyklus volání. Musíte se ujistit, že máte rekurzi adekvátně ukončenu. Následující jednoduchá funkce rekurzívně počítá do 10 za použití statické proměnné $count ke zjištění okamžiku pro ukončení:

function Test()
{
    static $count = 0;

    $count++;
    echo $count;
    if ($count < 10) {
        Test ();
    }
    $count--;
}

Proměnné s proměnnými názvy

Někdy je vhodné, aby se názvy proměnných mohly měnit, tj. aby mohly být dynamicky nastavovány a používány. Normální proměnná se nastavuje takovýmto konstruktem:

$a = "ahoj";

Proměnná s proměnným názvem vezme hodnotu proměnné a použije ji jako název proměnné. Ve výše uvedeném příkladu, ahoj lze použít jako název proměnné uvedením dvou symbolů dolaru:

$$a = "světe";

V této chvíli byly definovány dvě proměnné a byly uloženy do stromu symbolů PHP: $a s obsahem "ahoj" a $ahoj s obsahem "světe". Proto konstrukt:

echo "$a ${$a}";

provede přesně totéž jako:

echo "$a $ahoj";

tedy oba vyprodukují: ahoj světe.

Při použití proměnných s proměnnými názvy s poli musíte vyřešit problém víceznačnosti. Tj. když napíšete $$a[1], parser potřebuje vědět, máte-li na mysli použití $a[1] jako proměnné nebo chcete $$a jako proměnnou a potom index [1] v této proměnné. Syntaxe pro řešení této víceznačnosti je ${$a[1]} pro první případ a ${$a}[1] pro druhý.

Promměné zvenčí PHP

HTML formuláře (GET a POST)

Když se odešle formulář do PHP skriptu, jakékoli proměnné z tohoto formuláře budou automaticky dostupné v tomto skriptu. Je-li zapnuta konfigurační volba track_vars, budou tyto proměnné umístěny v asociativních polích $HTTP_POST_VARS, $HTTP_GET_VARS, a/nebo $HTTP_POST_FILES v závislosti na zdroji proměnných.

Pro více informací o těchto proměnných si laskavě přečtěte Předdefinované proměnné.

Příklad 8-1. Jednoduchá proměnná formuláře

<form action="foo.php" method="post"> Name: <input type="text" name="username"><br> <input type="submit"> </form>

Když se výše uvedený formulář odešle, hodnota vstupního textu bude dostupná v $HTTP_POST_VARS['username']. Je-li zapnuta konfigurační direktiva register_globals, proměnná bude dostupná i jako $username v globálním kontextu.

Poznámka: The magic_quotes_gpc configuration directive affects Get, Post and Cookie values. If turned on, value (It's "PHP!") will automagically become (It\'s \"PHP!\"). Escaping is needed for DB insertion. Also see addslashes(), stripslashes() and magic_quotes_sybase.

PHP also understands arrays in the context of form variables (see the related faq). You may, for example, group related variables together, or use this feature to retrieve values from a multiple select input:

Příklad 8-2. More complex form variables

<form action="array.php" method="post"> Name: <input type="text" name="personal[name]"><br> Email: <input type="text" name="personal[email]"><br> Beer: <br> <select multiple name="beer[]"> <option value="warthog">Warthog <option value="guinness">Guinness <option value="stuttgarter">Stuttgarter Schwabenbräu </select> <input type="submit"> </form>

In PHP 3, the array form variable usage is limited to single-dimensional arrays. In PHP 4, no such restriction applies.

IMAGE SUBMIT variable names

When submitting a form, it is possible to use an image instead of the standard submit button with a tag like:

<input type="image" src="image.gif" name="sub">

When the user clicks somewhere on the image, the accompanying form will be transmitted to the server with two additional variables, sub_x and sub_y. These contain the coordinates of the user click within the image. The experienced may note that the actual variable names sent by the browser contains a period rather than an underscore, but PHP converts the period to an underscore automatically.

HTTP Cookies

PHP transparently supports HTTP cookies as defined by Netscape's Spec. Cookies are a mechanism for storing data in the remote browser and thus tracking or identifying return users. You can set cookies using the setcookie() function. Cookies are part of the HTTP header, so the SetCookie function must be called before any output is sent to the browser. This is the same restriction as for the header() function. Any cookies sent to you from the client will automatically be turned into a PHP variable just like GET and POST method data.

If you wish to assign multiple values to a single cookie, just add [] to the cookie name. For example:

setcookie("MyCookie[]", "Testing", time()+3600);

Note that a cookie will replace a previous cookie by the same name in your browser unless the path or domain is different. So, for a shopping cart application you may want to keep a counter and pass this along. i.e.

Příklad 8-3. SetCookie Example

$Count++;
setcookie("Count", $Count, time()+3600);
setcookie("Cart[$Count]", $item, time()+3600);

Environment variables

PHP automatically makes environment variables available as normal PHP variables.

echo $HOME;  /* Shows the HOME environment variable, if set. */

Since information coming in via GET, POST and Cookie mechanisms also automatically create PHP variables, it is sometimes best to explicitly read a variable from the environment in order to make sure that you are getting the right version. The getenv() function can be used for this. You can also set an environment variable with the putenv() function.

Dots in incoming variable names

Typically, PHP does not alter the names of variables when they are passed into a script. However, it should be noted that the dot (period, full stop) is not a valid character in a PHP variable name. For the reason, look at it:

$varname.ext; /* invalid variable name */
Now, what the parser sees is a variable named $varname, followed by the string concatenation operator, followed by the barestring (i.e. unquoted string which doesn't match any known key or reserved words) 'ext'. Obviously, this doesn't have the intended result.

For this reason, it is important to note that PHP will automatically replace any dots in incoming variable names with underscores.

Determining variable types

Because PHP determines the types of variables and converts them (generally) as needed, it is not always obvious what type a given variable is at any one time. PHP includes several functions which find out what type a variable is. They are gettype(), is_array(), is_float(), is_int(), is_object(), and is_string().

Kapitola 9. Konstanty

PHP definuje několik konstant a poskytuje mechanismus pro definici dalších za běhu. Konstanty se hodně podobají proměnným s výjimkou dvou skutečností: konstanty se musí definovat pomocí funkce define(), a nemohou později nabývat jiných hodnot.

Předdefinované konstanty (dostupné vždy) jsou:

__FILE__: Název souboru skriptu, který je právě čten. Pokud je použita v souboru, který byl vložen pomocí "include" nebo "require", obsahuje název vloženého souboru, nikoli rodičovského.
__LINE__: Číslo řádku ve skriptu, který je právě čten. Pokud je použita v souboru vloženého pomocí "include" nebo "require", obsahuje pozici v rámci tohoto souboru.
PHP_VERSION: Textové vyjádření verze běžícího PHP parseru, např. '3.0.8-dev'.
PHP_OS: Název operačního systému, na kterém PHP parser běží, např. 'Linux'.
TRUE: Pravdivá hodnota (logická jednička).
FALSE: Nepravdivá hodnota (logická nula).
E_ERROR: Označuje neošetřitelnou chybu jinou než "parse error".
E_WARNING: Označuje stav, kdy PHP ví, že je něco špatně, ale bude dál pokračovat. Tyto stavy se dají ošetřit v samotném skriptu. Příkladem by byl neplatný "regexp" (regulární výraz) ve funkci ereg().
E_PARSE: Chyba při syntaktické analýze skriptu (chybná syntaxe). Ošetření není možné.
E_NOTICE: Došlo k něčemu, co by mohlo být chybou. Provádění skriptu pokračuje. Mezi příklady patří textový index pole neopatřený uvozovkami nebo práce s proměnnou, která ještě nebyla definována.
E_ALL: Všechny E_* konstanty shrnuté do jedné. Při použití s funkcí error_reporting() způsobí hlášení úplně všech problému zaregistrovaných PHP.

E_* konstanty se typicky používají s funkcí error_reporting() nastavení hladiny hlášení chyb. Viz všechny tyto konstanty v Ošetření chyb.

Další konstanty můžete definovat pomocí funkce define().

Všimněte si, že toto jsou konstanty, ne céčkovská makra; konstanty mohou reprezentovat pouze platná skalární data.

Příklad 9-1. Definice konstant

<?php define("CONSTANT", "Hello world."); echo CONSTANT; // vytiskne "Hello world." ?>

Příklad 9-2. Použití __FILE__ a __LINE__

<?php function report_error($file, $line, $message) { echo "Došlo k chybě v souboru $file na řádku $line: $message."; } report_error(__FILE__,__LINE__, "Něco je špatně!"); ?>

Kapitola 10. Výrazy

Výrazy jsou nejdůležitějšími stavebními kameny PHP. V PHP je téměř vše, co napíšete, výraz. Nejjednodušší, a přece nejpřesnější definicí výrazu je "všechno, co má hodnotu".

Nejzákladnějšími formami výrazů jsou konstanty a proměnné. Když napíšete "$a = 5", přiřazujete '5' do $a. '5' má, pochopitelně, hodnotu 5, nebo jinými slovy, '5' je výraz s hodnotou 5 (v tomto případě je '5' celočíselnou konstantou).

Po tomto přiřazení budete očekávat, že hodnota $a bude 5, takže kdybyste napsali $b = $a, očekávali byste totéž, jako při napsání $b = 5. Jinými slovy, $a je tedy výraz s hodnotou 5. Pokud vše pracuje správně, přesně to se také stane.

O něco složitějším příkladem výrazů jsou funkce. Uvažujme např. tuto funkci:

function foo ()
{
    return 5;
}

Za předpokladu, že jste dobře seznámeni s konceptem funkcí (pokud ne, nahlédněte do kapitoly o funkcích), byste předpokládali, že napsání $c = foo() je v zásadě totéž jako $c = 5, a máte pravdu. Funkce jsou výrazy s hodnotou jejich návratové hodnoty. Funkce foo() vrací 5, tudíž hodnota výrazu 'foo()' je 5. Obvykle funkce nevracejí konstantní hodnotu, nýbrž něco vypočítávají.

Hodnoty v PHP samozřejmě nemusejí být pouze celá čísla, a velmi často také nejsou. PHP podporuje tři typy skalárních hodnot: celočíselné, reálné (pohyblivá řádová čárka) a řetězce (skalární hodnoty jsou hodnoty, které nejde "rozbít" na menší části, narozdíl např. od polí). PHP podporuje také dva kompozitní (neskalární) typy: pole a objekty. Každý z těchto typů hodnot může být přiřazen do proměnné nebo vracen z funkce.

Uživatelé PHP/FI 2 by neměli pocítit změnu. Ale PHP jde ve výrazech mnohem dále, stejně jako mnoho jiných programovacích jazyků. PHP je výrazově orientovaný jazyk, ve smyslu, že téměř vše je výraz. Uvažujme příklad, kterým jsme se již zabývali, '$a = 5'. Ihned vidíme, že jsou zde zahrnuty dvě hodnoty, celočíselná konstanta '5' a hodnota $a, která je aktualizována na 5. Ale je pravda, že je tu ještě jedna hodnota, je to hodnota samotného přiřazení. Přiřazení jako takové ohodnocuje přiřazovanou hodnotu, v tomto případě 5. V praxi to znamená, že '$a = 5', bez ohledu na to co dělá, je výraz s hodnotou 5. Proto je '$b = ($a = 5)' totéž jako '$a = 5; $b = 5;' (středník označuje konec výrazu). Protože přiřezení jsou parsována zprava doleva, můžete také napsat '$b = $a = 5'.

Jiným dobrým příkladem orientace na výrazy je pre- a post-inkrementace a dekrementace. Uživatelé PHP/FI 2 a mnoha jiných jazyků znají notaci proměnná++ a proměnná--. To jsou inkrementační a dekrementační operátory. V PHP/FI 2 nemělo '$a++' žádnou hodnotu (není to výraz), a proto nešlo přiřadit nebo jinak použít. PHP rozšiřuje schopnosti přeměnou těchto konstrukcí ve výrazy, jako v C. V PHP, stejně jako v C, existují dva typy inkrementace - pre-inkrementace a post-inkrementace. Oba ve své podstatě inkrementují proměnnou a efekt na tuto proměnnou je totožný. Rozdíl je v hodnotě inkrementačního výrazu. Pre-inkrementace, zapsaná jako '++$var', ohodnocuje výraz inkrementovanou hodnotou (PHP inkrementuje proměnnou dříve, než přečte její hodnotu, proto "pre-inkrementace"). Post-inkrementace, zapsaná jako '$var++', ohodnocuje výraz původní hodnotou proměnné $var, před inkrementací (PHP inkrementuje proměnnou po přečtení její hodnoty, proto "post-inkrement").

Velmi častým typem výrazů jsou výrazy porovnávací. Tyto výrazy se ohodnocují 0 a 1 ve významu FALSE, resp. TRUE. PHP podporuje > (větší než), >= (větší nebo rovno), == (rovná se), != (nerovná se), < (menší než) a <= (menší nebo rovno). Tyto výrazy se nejčastěji používají v podmínkách, jako je konstrukt if.

Posledním příkladem výrazů, kterým se budeme zabývat, je kombinací přiřazení a operátorů. Již víte, že když chcete inkrementovat $a o jedničku, jednoduše napíšete '$a++' nebo '++$a'. Ale co když chcete hodnotu zvýšit o jiné číslo, např. o 3? Mohli byste napsat '$a++' víckrát za sebou, ale to samozřejmě není efektivní ani pohodlné. Mnohem praktičtější je napsat '$a = $a + 3'. Výraz '$a + 3' ohodnocuje hodnotu $a plus 3 a je přiřazen zpět do $a, což dává $a inkrementované o 3. V PHP, stejně jako v řadě jiných jazyků (jako je C), to můžete napsat kratším způsobem, který se časem stane jasnější i rychlejší k pochopení. Přičtení 3 k aktuální hodnotě $a lze zapsat jako '$a += 3'. Přesně to znamená "vezmi hodnotu $a, přičti k ní 3 a přiřaď zpět do $a". Kromě kratšího a přehlednějšího zápisu je výhodou také rychlejší provedení. Hodnota '$a += 3', jako hodnota regulérního přiřazení, je přiřazovaná hodnota. Uvědomte si, že to NENÍ 3, nýbrž $a plus 3 (což je hodnota výrazu přiřazovaného do $a). Takto lze použít jakýkoli binární operátor, například '$a -= 5' (odečti 5 od hodnoty $a), '$b *= 7' (vynásob hodnotu $b číslem 7) apod.

Je tu ještě jeden výraz, který se může zdát zvláštní, pokud jste ho ještě neviděli v jiných jazycích: ternární podmíněný operátor:

$prvni ? $druhy : $treti

Pokud hodnota prvního podvýrazu je TRUE (nenulová), je ohodnocen druhý podvýraz a je výsledkem celého podmíněného výrazu. Jinak je ohodnocen třetí podvýraz a je pak hodotou celého výrazu.

Následující příklad by měl pomoci lépe pochopit pre- a post-inkrementaci i výrazy obecně:

function double($i)
{
    return $i*2;
}
$b = $a = 5;        /* přiřaď hodnotu pět do proměnných $a a $b */
$c = $a++;          /* proveď post-inkrement, přiřaď původní hodnotu $a 
                       (5) do $c */
$e = $d = ++$b;     /* proveď pre-inkrement, přiřaď inkrementovanou hodnotu 
                       $b (6) do $d a $e */

/* nyní jsou hodnoty proměnných $d a $e rovny 6 */

$f = double($d++);  /* přiřaď dvakrát hodnotu $d <emphasis>před</emphasis> 
                       inkrementací, 2*6 = 12, do $f */
$g = double(++$e);  /* přiřaď dvakrát hodnotu $e <emphasis>po</emphasis>
                       inkrementaci, 2*7 = 14 do $g */
$h = $g += 10;      /* nejdříve je $g inkrementováno o 10 má pak hodnotu 24. 
                       Hodnota přiřazení (24) se přiřadí do $h a $h tím
                       získává také hodnotu 24. */

Na začátku kapitoly bylo řečeno, že si popíšeme různé typy konstruktů, a jak bylo slíbeno, výrazy mohou být konstrukty. V tomto případě mají konstrukty formát 'expr' ';', což znamená "výraz následovaný středníkem. V konstruktu '$b=$a=5;', je $a=5 platný výraz, ale samo o sobě to není konstrukt.'$b=$a=5;' je i platný konstrukt.

Pozn. překladatele: Předchozím odstavci (občas i jinde) používám termín "konstrukt" pro anglické slovo "statement". Tento překlad není příliš korektní, ale v české programátorské mluvě neexistuje vhodný termín. Kdyby někdo věděl o lepším, napište mi, prosím, na luk@php.net.

Poslední věcí, která si zaslouží zmínku, je pravdivostní hodnota výrazů. V mnoha případech, hlavně podmínkách a cyklech, vás nezajímá konkrétní hodnota výrazu, nýbrž pouze to, jestli je TRUE nebo FALSE. Konstanty TRUE a FALSE (malá/velká písmena nehrají roli) představují dvě možné boolovské (pravdivostní) hodnoty. V případě potřeby je výraz automaticky převeden na typ boolean. Detailnější informace o způsobu konverze - viz sekce o typové konverzi.

PHP poskytuje plnou a silnou implementaci výrazů a úplně je zdokumentovat přesahuje rozsah tohoto manuálu. Výše uvedené příklady by vám měli naznačit, co jsou vůbec výrazy a jak konstruovat užitečné výrazy. Ve zbývající části manuálu budeme psát expr jakožto jakýkoli platný PHP výraz.

Kapitola 11. Operátory

Aritmetické operátory

Vzpomínáte si na základní aritmetiku ze školy? Tohle je úplně stejné.

Tabulka 11-1. Aritmetické operátory

Příklad	Název	Výsledek
$a + $b	Sčítání	Součet $a a $b.
$a - $b	Odčítání	ROzdíl $a a $b.
$a * $b	Násobení	Součin $a a $b.
$a / $b	Dělení	Podíl $a a $b.
$a % $b	Zbytek	Zbytek po dělení $a a $b.

Operátor dělení ("/") vrací celočíselnou hodnotu (výsledek celočíselného dělení) právě tehdy, když oba operandy jsou celá čísla (nebo řetězce, které se dají převést na celá čísla) a podíl je celé číslo. Pokud některý z operandů celočíselný není nebo výsledek není celé číslo, vrátí se hodnota v plovoucí řádové čárce (float).

Operátory přiřazení

Základním přiřazovacím operátorem je "=". Mohli byste si zprvu myslet, že se jedná o "rovná se". Nikoliv. Skutečně to znamená, že se levému operandu přiřadí hodnota výrazu vpravo (tj. "nastav na", "přiřaď do" atd.).

Hodnotou výrazu přiřazení je hodnota, která se přiřazuje. Tj. hodnotou "$a = 3" je číslo 3. To vám umožňuje provádět různé triky:

$a = ($b = 4) + 5; // $a se ted rovná 9, a $b bylo nastaveno na 4.

Kromě základního operátoru přiřazení existují ještě "kombinované operátory" pro všechny binární aritmetické a řetězové operátory, které umožňují použít hodnotu ve výrazu a pak hodnotu tohoto výrazu přiřadit zpět. Například:

$a = 3;
$a += 5; // nastaví $a na hodnotu 8, jako kdybychom řekli: $a = $a + 5;
$b = "Ahoj ";
$b .= "tam!"; // nastaví $b na "Ahoj tam!", přesně tak, jako $b = $b . "tam!";

Uvědomte si, že přiřazení zkopíruje hodnotu původní proměnné do nové proměnné (přiřazení hodnoty), takže změny jedné z nich se na druhé proměnné neprojeví. To může mít význam také tehdy, když potřebujete zkopírovat něco jako obrovské pole uvnitř krátkého cyklu. PHP 4 podporuje přiřazení odkazem použitím syntaxe $var = &$othervar;, ale v PHP 3 to provést nelze. "Přiřazení odkazem" znamená, že obě proměnné ukazují na tatáž data a nic se nikam nekopíruje. Chcete-li se o odkazech dozvědět více, čtěte prosím Vysvětlení referencí.

Bitové operátory

Bitové operátory umožňují "přehodit" konkrétní bit v celočíselné hodnotě (integer) na jedničku nebo nulu. Pokud jsou jak levý, tak pravý parametr řetězce, pracují bitové operátory na znacích v těchto řetezcích.

<?php
    echo 12 ^ 9; // Vypíše '5'

    echo "12" ^ "9"; // Vypíše znak Backspace (ascii 8)
                     // ('1' (ascii 49)) ^ ('9' (ascii 57)) = #8

    echo "hallo" ^ "hello"; // Vypíše ascii hodnoty #0 #4 #0 #0 #0
                            // 'a' ^ 'e' = #4
?>

Tabulka 11-2. Bitové operátory

Příklad	Název	Výsledek
$a & $b	And (log. součin)	Nastavují se bity, kde je jednička v $a i v $b.
$a \| $b	Or(log. součet)	Nastavují se bity, kde je jednička v $a nebo v $b (i v obou současně).
$a ^ $b	Xor (exkluzívní log. součet)	Nastavují se bity, kde je jednička v $a nebo v $b, ale ne v obou současně.
~ $a	Not (negace)	Tam, kde je nula, bude jednička, a naopak.
$a << $b	Posun vlevo	Posune bity v $a o $b kroků (míst) vlevo (každý krok znamená "násobení dvěma").
$a >> $b	Posun vpravo	Posune bity v $a o $b kroků (míst) vpravo (každý krok znamená "dělení dvěma").

Operátory porovnání

Operátory porovnání, jak název napovídá, slouží k porovnání dvou hodnot.

Tabulka 11-3. Operátory porovnání

Příklad	Název	Výsledek
$a == $b	Rovnost	`TRUE`, právě když je $a rovno $b.
$a === $b	Identita	`TRUE` když je $a rovno $b a navíc tétož typu (pouze PHP 4).
$a != $b	Nerovnost	`TRUE` právě když $a není rovno $b.
$a <> $b	Nerovnost	`TRUE` právě když $a není rovno $b.
$a !== $b	Neidentita	`TRUE` když $a není rovno $b nebo nejsou téhož typu (pouze PHP 4).
$a < $b	Menší než	`TRUE` když je $a ostře menší než $b.
$a > $b	Větší než	`TRUE` když je $a ostře větší než $b.
$a <= $b	Menší nebo rovno	`TRUE` když je $a menší nebo rovno $b.
$a >= $b	Větší nebo rovno	`TRUE` když je $a větší nebo rovno $b.

Jiným podmínkovým operátorem je "?:" (ternární) operátor, který funguje stejně jako v C a mnohých jiných jazycích.

(expr1) ? (expr2) : (expr3);

Výraz je ohodnocen jako hodnota expr2 když má expr1 hodnotu TRUE, a expr3 když má expr1 hodnotu FALSE.

Operátory řízení chyb

PHP podporuje jeden operátor řízení chyb: znak at (@). Když ho předřadíte výrazu v PHP, jakékoli chybové zprávy, které se mohou generovat ve výrazu, budou ignorovány.

Pokud je zapnutotrack_errors, budou se všechny chybové zprávy generované výrazem ukládat do globální proměnné $php_errormsg. Tato proměnná bude přepsána při každé chybě, takže ji testujte vždy co nejdříve, pokud ji chcete používat.

<?php
/* Intentional file error */
$my_file = @file ('non_existent_file') or
    die ("Failed opening file: error was '$php_errormsg'");

// this works for any expression, not just functions:
$value = @$cache[$key]; 
// will not issue a notice if the index $key doesn't exist.

?>

Poznámka: Operátor @ pracuje pouze na výrazech. Platí jednoduché pravidlo: můžete-li získat hodnotu něčeho, můžete před to dát operátor @. To se týká například proměnných, funkcí, volání include() konstant a podobně. Nemůžete ho předřadit definicím funkcí nebo tříd a podmínkovým strukturám typu if nebo foreach.

Viz také error_reporting().

Varování

V současnosti předřazení operátoru řízení chyb "@" vyřadí i hlášení kritických chyb, které způsobí ukončení provádění skriptu. To mj. znamená, že pokud použijete "@" k potlačení chyb z nějaké funkce, a tato funkce není k dispozici nebo obsahuje chyby, skript zde skončí bez jakékoli indikace, co se stalo.

Prováděcí operátory

PHP podporuje jeden prováděcí operátor: obrácené apostrofy (``). Uvědomte si, že to nejsou obyčejné apostrofy! PHP se pokusí provést obsah uzavřený mezi těmito znaky jako příkaz shellu; výstup je vrácen (tzn. nebude pouze vypsán na výstupů může být přiřazen proměnné).

$output = `ls -al`;
echo "<pre>$output</pre>";

Poznámka: Operátor může být vyřazen, pokud je aktivní bezpečný režim nebo je vypnuto shell_exec().

Viz také escapeshellcmd(), exec(), passthru(), popen(), shell_exec(), a system().

Inkrementační/Dekrementační operátory

PHP podporuje pre- a post inkrementační a dekrementační operátory ve stylu C.

Tabulka 11-4. Inkrementační/dekrementační operátory

Příklad	Název	Účinek
++$a	Pre-inkrementace	Inkrementuje $a o jedničku, potom vrátí $a.
$a++	Post-inkrementace	Vrátí $a, potom inkrementuje $a o jedničku.
--$a	Pre-dekrementace	Dekrementuje $a o jedničku, potom vrátí $a.
$a--	Post-dekrementace	Vrátí $a, potom dkrementuje $a o jedničku.

Zde je příklad jednoduchého skriptu:

<?php
echo "<h3&gt;Postinkrementace</h3&gt;";
$a = 5;
echo "Mělo by být 5: " . $a++ . "<br>\n";
echo "Mělo by být 6: " . $a . "<br>\n";

echo "<h3>Preinkrementace</h3>";
$a = 5;
echo "Mělo by být 6: " . ++$a . "<br>\n";
echo "Mělo by být 6: " . $a . "<br>\n";

echo "<h3>Postdekrementace</h3>";
$a = 5;
echo "Mělo by být 5: " . $a-- . "<br>\n";
echo "Mělo by být: " . $a . "<br>\n";

echo "<h3>Predekrementace</h3>";
$a = 5;
echo "Mělo by být 4: " . --$a . "<br>\n";
echo "Mělo by být 4: " . $a . "<br>\n";
?>

Logické operátory

Tabulka 11-5. Logické operátory

Příklad	Název	Výsledek
$a and $b	And	`TRUE` když $a i $b jsou `TRUE`.
$a or $b	Or	`TRUE` když $a nebo $b je `TRUE`.
$a xor $b	Xor	`TRUE` když $a nebo $b je `TRUE`, ale ne oba současně.
! $a	Not	`TRUE` když $a není `TRUE`.
$a && $b	And	`TRUE` když $a i $b jsou `TRUE`.
$a \|\| $b	Or	`TRUE` když $a nebo $b je `TRUE`.

Důvodem pro dvě různé varianty operátorů "and" a "or" je to, že mají jinou prioritu. (Viz Priorita operátorů.)

Priorita operátorů

Priorita operátoru specifikuje, jak "těsně" váže dva výrazy mezi sebou. Například výraz 1 + 5 * 3, výsledkem je 16 a nikoli 18, protože operátor násobení ("*") má vyšší prioritu než operátor sčítání ("+"). K vynucení priority můžeme v případě potřeby použít závorky. Kupř. (1 + 5) * 3 má hodnotu 18.

Následující tabulka ukazuje přehled operátorů vzestupně seřazených podle priority.

Tabulka 11-6. Priorita operátorů

Asociativita	Operátory
levá	,
levá	or
levá	xor
levá	and
pravá	print
levá	= += -= *= /= .= %= &= \|= ^= ~= <<= >>=
levá	? :
levá	\|\|
levá	&&
levá	\|
levá	^
levá	&
bez asociativity	== != === !==
bez asociativity	< <= > >=
levá	<< >>
levá	+ - .
levá	* / %
pravá	! ~ ++ -- (int) (double) (string) (array) (object) @
pravá	[
bez asociativity	new

Řetězcové operátory

Existují dva řetezcové operátory. Jedním je operátor spojení ('.'), který vrací spojení pravého a levého argumentu. Druhým je operátor spojujícího přiřazení ('.='), jenž připojí argument na pravé straně k argumentu na straně levé. Pro více informací si laskavě přečtěte Operátory přiřazení.

$a = "Ahoj ";
$b = $a . "světe!"; // nyní $b obsahuje "Ahoj světe!"

$a = "Ahoj ";
$a .= "světe!";     // nyní $a obsahuje "Ahoj světe!"

Kapitola 12. Řídicí struktury

Jakýkoli PHP skript je složen ze série konstruktů. Konstrukt může být přiřazení, volání funkce, cyklus, podmínka, stejně jako konstrukt, který nic nedělá (prázdný konstrukt). Konstrukt obvykle končí středníkem. Navíc lze konstrukty seskupit do skupiny (bloku) uzavřené složenými závorkami. Tento blok je sám o sobě konstruktem. V této kapitole jsou popsány různé typy konstruktů.

`if`

Konstrukt if je jedním z nejdůležitějších prvků v mnoha jazycích, včetně PHP. Umožňuje podmíněné provádění kusu kódu. Struktura if v PHP je podobná struktuře v C:

if (expr)
    statement

Jak je popsáno v sekci o výrazech, výraz expr je ohodnoce svou boolovskou hodnotou. Poku je expr ohodnocen jako TRUE, PHP provede statement; je-li ohodnocen jako FALSE, neprovede se nic. Více informací o to, jak se výrazy ohodnocují jako FALSE najdete v části 'Konverze na typ boolean'.

Následující příklad by vypsal a je větší než b, pokud $a je větší než $b:

if ($a > $b)
    print "a je větší než b";

Často byste chtěli, aby se podmíněně prováděl více než jeden konstrukt. Není samozřejmě nutné každý konstrukt zabalit do struktury if. Místo toho můžete seskupit více konstruktů do bloku. Například tento kód by zobrazil a je větší než b, pokud $a je větší než $b a přiřadil by hodnotu $a do $b:

if ($a > $b) {
    print "a je větší než b";
    $b = $a;
}

Konstrukty if mohou být libovolně vnořovány do jiných konstruktů if, což poskytuje plnou flexibilitu podmíněného provádění různých částí programu.

`else`

Často také můžete chtít něco provádět, pokud je jistá podmínka splněna, a něco jiného, když splněna není. To umožňuje konstrukt else. else rozšiřuje konstrukt if o provádění kódu v případě, že výraz v konstruktu if je ohodnocen jako FALSE. Například následující kód vypíše a je větší než b, pokud $a je větší než $b, a a NENÍ větší než b v ostatních případech:

if ($a > $b) {
    print "a je větší než b";
} else {
    print "a NENÍ větší než b";
}

Konstrukt v else se provádí, pouze pokud je výraz v if ohodnocen jako FALSE, a pokud by zde byly nějaké výrazy elseif - pouze pokud by byly také ohodnoceny jako FALSE (viz elseif).

`elseif`

Jak název napovídá, elseif, je kombinací if a else. Stejně jako else, rozšiřuje konstrukt if k provádění odlišných konstruktů v případě, že jevýraz původního konstruktu if ohodnocen jako FALSE. Tedy, narozdíl od else, se provádí pouze tehdy, je-li výraz v podmínce elseif ohodnocen jako TRUE. Například následující kód vypíše a je větší než b, a se rovná b nebo a je menší než b:

if ($a > $b) {
    print "a je větší než b";
} elseif ($a == $b) {
    print "a se rovná b";
} else {
    print "a je menší než b";
}

V rámci jednoho konstruktu if může být více konstruktů elseif. Provádí se první konstrukt elseif (pokud vůbec nějaký), jehož výraz je ohodnocen TRUE. V PHP můžete napsat i 'else if' (dvěma slovy), chování bude naprosto totožné jako u 'elseif' (jedním slovem). Syntaktický význam je mírně odlišný (znáte-li C, je to stejné), avšak ve výsledku dostaneme přesně totožné chování.

Konstrukt elseif se provádí, pouze jsou-li příslušný (bezprostředně předcházející) výraz konstruktu if a výrazy všech příslušných předcházejících konstruktů elseif ohodnoceny jako FALSE, a konkrétní výraz v elseif ohodnocen jako TRUE.

Alternativní syntaxe řídicích struktur

PHP nabízí alternativní syntaxi pro některé z řídicích struktur, jmenovitě if, while, for, foreach, a switch. V každém z těchto případů je základním formátem alternativní syntaxe záměna otvírací závorky za dvojtečku (:) a uzavírací závorky za endif;, endwhile;, endfor;, endforeach;, resp. endswitch;.

<?php if ($a == 5): ?>
A se rovná 5
<?php endif; ?>

Ve výše uvedeném příkladu je HTML blok vnořen do konstruktu if napsaném alternativní syntaxí. Tento HTML blok by se zobrazil pouze v případě, že je $a rovno 5.

Alternativní syntaxi lze použít i pro else a elseif. Následující příklad ukazuje strukturu if, elseif a else v alternativním formátu:

if ($a == 5):
    print "a se rovná 5";
    print "...";
elseif ($a == 6):
    print "a se rovná 6";
    print "!!!";
else:
    print "a není ani 5, ani 6";
endif;

Další příklady - viz také while, for, a if.

`while`

Cykly while jsou nejjednodušším typem cyklů v PHP. Chovají se jako jejich protějšci v C. Základí formát konstruktu while je tento:

while (expr) statement

Význam konstruktu while je snadno pochopitelný. Říká PHP, že má provádět vnořený(é) konstrukt(y) tak dlouho, dokud je výraz ve while roven TRUE. Hodnota výrazu je testována pokaždé na začátku cyklu (v každé iteraci), takže i když se tato hodnota během provádění vnořených konstruktů změní, provede se zbytek kódu uvnitř cyklu - v konkrétní iteraci - až do konce (každé provedení kódu uvnitř cyklu je jedna iterace). Někdy, když je výraz ve while ohodnocen jako FALSE již při vstupu do cyklu, vnořený kód se neprovede vůbec.

Podobně, jako v případě if, můžete i zde seskupovat konstrukty uvnitř cyklu while ohraničením tohoto kódu složenými závorkami nebo za použití alternativní syntaxe:

while (expr): statement ... endwhile;

Následující příklady jsou identické, oba vypíší čísla od 1 do 10:

/* příklad 1 */

$i = 1;
while ($i <= 10) {
    print $i++;  /* vytištěná hodnota by byla rovna
                    $i před inkrementací
                    (post-inkrementace) */
}

/* příklad 2 */

$i = 1;
while ($i <= 10):
    print $i;
    $i++;
endwhile;

`do..while`

Cykly do..while jsou velmi podobné cyklům while kromě toho, že pravdivost výrazu se testuje na konci každé iterace namísto jejího začátku. Hlavní rozdíl oproti běžným cyklům while je ten, že první iterace cyklu do..while se provede vždy (pravdivostní výraz je testován až na konci iterace), což u cyklu while není zaručeno (pravdivostní výraz je testován na začátku iterace; pokud je ohodnocen jako FALSE, provádění cyklu hned skončí).

Toto je jediná syntaxe pro cykly do..while:

$i = 0;
do {
   print $i;
} while ($i>0);

Výše uvedený cyklus by se provedl právě jednou, protože po první iteraci, když se testuje pravdivostní výraz, je tento ohodnocen jako FALSE ($i není větší než 0) a provádění cyklu končí.

Pokročilí programátoři v C mohou znát i odlišné použití cyklu do..while. Kód se uzavře do do..while(0) a použije se příkaz break. To umožňuje přerušit provádění cyklu uprostřed kódu, jak je znázorněno v tomto příkladu:

do {
    if ($i < 5) {
        print "i není dost velké";
        break;
    }
    $i *= $factor;
    if ($i < $minimum_limit) {
        break;
    }
    print "i je ok";

     ...zpracuj i...

} while(0);

Nedělejte si nic z toho, že tomu hned a beze zbytku nerozumíte. Můžete psát skripty, a to i velmi účinné skripty, i bez použití této 'finty'.

`for`

Cykly for jsou nejsložitějšími cykly v PHP. Chovají se stejně, jako jejich soukmenovci v C. Syntaxe cyklu for je následující:

for (expr1; expr2; expr3) statement

První výraz (expr1) je ohodnocen (proveden) jednou, bezpodmínečně, na začátku cyklu.

Na začátku každé iterace je ohodnocen výraz expr2. Pokud má hodnotu TRUE, cyklus pokračuje a zpracovává se kód uvnitř cyklu. Je-li naopak jeho hodnota FALSE, provádění cyklu končí.

Na konci každé iterace se ohodnotí (provede) výraz expr3.

Každý z výrazů může být prázdný. Prázdný výraz expr2 znamená, že cyklus bude probíhat nekonečně dlouho (PHP, stejně jako C, implicitně předpokládá hodnotu TRUE). To nemusí být tak bez užitku, jak si můžete myslet. Často můžete totiž chtít ukončit cyklus pomocí podmíněného příkazu break, namísto použití pravdivostního výrazu v konstruktu cyklu for.

Předpokládejme následující příklady. Všechny zobrazí čísla od 1 do 10:

/* příklad 1 */

for ($i = 1; $i <= 10; $i++) {
    print $i;
}

/* příklad 2 */

for ($i = 1;;$i++) {
    if ($i > 10) {
        break;
    }
    print $i;
}

/* příklad 3 */

$i = 1;
for (;;) {
    if ($i > 10) {
        break;
    }
    print $i;
    $i++;
}

/* příklad 4 */

for ($i = 1; $i <= 10; print $i, $i++);

První příklad samozřejmě vypadá nejlépe (nebo možná i ten čtvrtý), ale můžete přijít na to, že schopnost používat prázdné výrazy v cyklech for nemusí být někdy úplně k zahození.

PHP podporuje pro cykly for také alternativní "dvojtečkovou syntaxi".

for (expr1; expr2; expr3): statement; ...; endfor;

Jiné jazyky mají konstrukt foreach k traverzování polí nebo hashů. V PHP 3 nic takového není, PHP 4 ano (viz foreach). V PHP 3 můžete k dosažení stejného efektu kombinovat while s funkcemi list() a each(). Příklady najdete v dokumentaci.

`foreach`

PHP 4 (ne PHP 3) zahrnuje konstrukt foreach, podobně jako Perl a různé další jazyky. To poskytuje snadný způsob k iteraci přes pole. Existují dvě syntaxe; ta druhá je menším, avšak užitečným rozšířením té první:

foreach(array_expression as $value) statement
foreach(array_expression as $key => $value) statement

První forma traverzuje pole dané výrazem array_expression. V každé iteraci je hodnota aktuálního elementu přiřazena do $value a vnitřní ukazatel na pole je zvýšen o jednotku (tzn. v příští iteraci budete hledět na následující element).

Druhá forma dělá totéž, kromě toho, že aktuální klíč elementu bude v každé iteraci přiřazen do proměnné $key.

Poznámka: Když foreach začne provádění první iterace, je vnitřní ukazatel automaticky nastaven na první element pole. To znamená, že před foreach nemusíte volat reset().

Poznámka: Uvědomte si také, že foreach pracuje na kopii specifikovaného pole, nikoli na poli samotném, proto ukazatel na pole není modifikován tak, jako konstruktem each() a změny na vráceném elementu se na původním poli neprojeví.

Poznámka: foreach nepodporuje možnost potlačit chybová hlášení použitím '@'.

Můžete si všimnout, že následující příklady jsou funkčně totožné:

reset ($arr);
while (list(, $value) = each ($arr)) {
    echo "Hodnota: $value<br>\n";
}

foreach ($arr as $value) {
    echo "Hodnota: $value<br>\n";
}

Následující příklady jsou rovněž funkčně totožné:

reset ($arr);
while (list($key, $value) = each ($arr)) {
    echo "Klíč: $key; Hodnota: $value<br>\n";
}

foreach ($arr as $key => $value) {
    echo "Klíč: $key; Hodnota: $value<br>\n";
}

Další příklady demonstrující použítí:

/* foreach příklad 1: pouze hodnota */

$a = array (1, 2, 3, 17);

foreach ($a as $v) {
   print "Současná hodnota \$a: $v.\n";
}

/* foreach příklad 2: hodnota (pro ilustraci je vypsán i klíč) */

$a = array (1, 2, 3, 17);

$i = 0; /* pouze pro ilustrativní účely */

foreach($a as $v) {
    print "\$a[$i] => $v.\n";
    $i++;
}

/* foreach příklad 3: klíč a hodnota */

$a = array (
    "jedna" => 1,
    "dvě" => 2,
    "tři" => 3,
    "sedmnáct" => 17
);

foreach($a as $k => $v) {
    print "\$a[$k] => $v.\n";
}

/* foreach příklad 4: vícerozměrná pole */

$a[0][0] = "a";
$a[0][1] = "b";
$a[1][0] = "y";
$a[1][1] = "z";

foreach($a as $v1) {
    foreach ($v1 as $v2) {
        print "$v2\n";
    }
}

/* foreach příklad 5: dynamická pole */

foreach(array(1, 2, 3, 4, 5) as $v) {
    print "$v\n";
}

`break`

break ukončuje provádění aktuálního konstruktu for, foreach while, do..while nebo switch.

break akceptuje nepovinný číselný argument, který říká, z kolika vnořených struktur se má vyskočit.

$arr = array ('jedna', 'dvě', 'tři', 'čtyři', 'stop', 'pět');
while (list (, $val) = each ($arr)) {
    if ($val == 'stop') {
        break;    /* Tady byste mohli napsat také 'break 1;'. */
    }
    echo "$val<br>\n";
}

/* Použití nepovinného argumentu. */

$i = 0;
while (++$i) {
    switch ($i) {
    case 5:
        echo "Při 5<br>\n";
        break 1;  /* Ukončuje pouze switch. */
    case 10:
        echo "Při 10; konec<br>\n";
        break 2;  /* Ukončuje switch a while. */
    default:
        break;
    }
}

`continue`

continue se používá uvnitř cyklů k přeskočení zbytku aktuální iterace a bezprostřednímu přechodu na následující iteraci.

continue akceptuje nepovinný číselný argument, který říká, kolik úrovní cyklů se má naráz dokončit.

while (list ($key, $value) = each ($arr)) {
    if (!($key % 2)) { // přeskoč sudé členy
        continue;
    }
    do_something_odd ($value);
}

$i = 0;
while ($i++ &lt; 5) {
    echo "Vnější<br>\n";
    while (1) {
        echo "&nbsp;&nbsp;Střední<br>\n";
        while (1) {
            echo "&nbsp;&nbsp;Vnitřní<br>\n";
            continue 3;
        }
        echo "Toto se nikdy nevytiskne.<br>\n";
    }
    echo "Ani tohle se neprovádí.<br>\n";
}

`switch`

Konstrukt switch je podobná sérii konstruktů IF, testujících tentýž výraz. V mnoha případech můžete chtít porovnávat stejnou proměnnou (nebo výraz) s mnoha různými hodnotami a provádět různé kusy kódu v závislosti na tom, které hodnotě se rovná. To je přesně to, k čemu je switch.

Následující dva příklady představují dva odlišné způsoby, jak napsat totéž; jeden používá sérii podmínek if, zatímco druhý je založen na konstruktu switch:

if ($i == 0) {
    print "i se rovná 0";
}
if ($i == 1) {
    print "i se rovná 1";
}
if ($i == 2) {
    print "i se rovná 2";
}

switch ($i) {
    case 0:
        print "i se rovná 0";
        break;
    case 1:
        print "i se rovná 1";
        break;
    case 2:
        print "i se rovná 2";
        break;
}

Je důležité pochopit, jak se konstrukt switch provádí, aby se zabránilo chybám. Konstrukt switch provádí řádek po řádku (resp. konstrukt po konstruktu). Na začátku není proveden žádný kód. Pouze tehdy, když se najde case s hodnotou odpovídající hodnotě výrazu u switch, začne PHP provádět následující konstrukty. Vykonávání kódu pokračuje, dokud se nedosáhne konce bloku switch nebo prvního příkazu break. Pokud nenapíšete na konec bloku po case příkaz break, bude PHP pokračovat v provádění dalších konstruktů (po dalším case). Například:

switch ($i) {
    case 0:
        print "i se rovná 0";
    case 1:
        print "i se rovná 1";
    case 2:
        print "i se rovná 2";
}

Zde, pokud se $i rovná 0, se budou provádět všechny příkazy "print"! Pokud se $i rovná 1, PHP provede poslední dva příkazy, a pouze rovná-li se $i číslu 2, obdržíte "očekávané" chování a zobrazí se pouze "i se rovná 2". Takže je důležité nezapomenout na příkaz break (kromě případu, kdy ho chcete vynechat záměrně k dosažení určitého cíle).

V konstruktu switch se podmínka testuje pouze jednou a výsledek se porovnává s každou hodnotou v case. V případě elseif se podmínka pokaždé testuje znovu. Pokud je vaše podmínka komplikovanější než jednoduché porovnání a/nebo je uvnitř cyklu, switch může být rychlejší.

Seznam konstruktů za case může být také prázdný, což jednoduše předá řízení následujícímu case.

switch ($i) {
    case 0:
    case 1:
    case 2:
        print "i je menší než 3, ale nezáporné";
        break;
    case 3:
        print "i je 3";
}

Speciální case je "default". Vyhovuje všem ostatním hodnotám, které nejsou pokryty některým z ostatních case a má být vždy jako poslední. Například:

switch ($i) {
    case 0:
        print "i se rovná 0";
        break;
    case 1:
        print "i se rovná 1";
        break;
    case 2:
        print "i se rovná 2";
        break;
    default:
        print "i se nerovná 0, 1 ani 2";
}

Výraz v case může být libovolný výraz, jehož hodnota je jednoduchého typu, tj. celé nebo reálné číslo nebo řetězec. Pole ani objekty nelze použít, ledaže by odkazovaly na jednoduchý typ.

Alternativní syntaxe pro konstrukty switch je podporována. Pro víc informací viz Alternativní syntaxe řídicích struktur .

switch ($i):
    case 0:
        print "i se rovná 0";
        break;
    case 1:
        print "i se rovná 1";
        break;
    case 2:
        print "i se rovná 2";
        break;
    default:
        print "i se nerovná 0, 1 ani 2";
endswitch;

`declare`

Konstrukt declare se používá k nastavení prováděcích direktiv pro blok kódu. Syntaxe declare je podobná syntaxi ostatnícj konstruktů pro řízení toku:

declare (directive) statement

Část directive umožňuje nastavit chování bloku, který má být ovlivněn pomocí declare. V současnosti je rozpoznávána pouze jediná direktiva: ticks. (Pro více informací viz níže - direktiva ticks)

Část statement bloku declare bude provedena - jak bude provedena a jaké vedlejší efekty nastanou během provádění může záležet na direktivě nastavené v bloku directive.

Ticks

Tick je událost, která nastane pro každých N nízkoúrovňových konstruktů provedených parserem uvnitř bloku declare. Hodnota N je specifikována pomocí ticks=N uvnitř sekce directive bloku declare.

Událost(i), která nastane při každém ticku, se specifikuje pomocí register_tick_function(). Více podrobností - viz příklad níže. Uvědomte si, že na každý tick může nastat více než jedna událost.

Příklad 12-1. Profile a section of PHP code

<pre> <?php // A function that records the time when it is called function profile ($dump = FALSE) { static $profile; // Return the times stored in profile, then erase it if ($dump) { $temp = $profile; unset ($profile); return ($temp); } $profile[] = microtime (); } // Set up a tick handler register_tick_function("profile"); // Initialize the function before the declare block profile (); // Run a block of code, throw a tick every 2nd statement declare (ticks=2) { for ($x = 1; $x < 50; ++$x) { echo similar_text (md5($x), md5($x*$x)), "<br>"; } } // Display the data stored in the profiler print_r (profile (TRUE)); ?> </pre>
The example profiles the PHP code within the 'declare' block, recording the time at which every second low-level statement in the block was executed. This information can then be used to find the slow areas within particular segments of code. This process can be performed using other methods: using ticks is more convenient and easier to implement.

Ticks are well suited for debugging, implementing simple multitasking, backgrounded I/O and many other tasks.

return

Zavolán uvnitř funkce, konstrukt return() okamžitě ukončí provádění této funkce a vrací svůj argument jako hodnotu volání funkce. return() také obdobně ukončí provádění konstruktu eval() nebo celého skriptu.

Pokud se volá z globálního kontextu, provádění skriptu se ukončí. Byl-li aktuální skript vložen pomocí include() nebo require(), předá se řízení volajícímu souboru. Navíc, bylo-li použito include(), bude hodnota specifikovaná v return() vrácena jako hodnota volání include(). Pokud se return() zavolá z hlavního souboru skriptu, provádění skončí. Když se jedná o soubor specifikovaný pomocí konfiguračních voleb auto_prepend_file nebo auto_append_file v konfiguračním souboru, zpracování souboru končí.

Více informací - viz Návratové hodnoty.

Poznámka: Uvědomte si, že return() je jazykový konstrukt, a nikoli funkce -- uzavření argumentů do závorek není nutné. Obvykle se vynechávají, ale nezáleží na tom, zda se použijí či nikoli.

require()

Konstrukt require() vloží a ohodnotí specifikovaný soubor.

require() vloží a ohodnotí specifikovaný soubor. Podrobné informace o tom, jak vkládání pracuje, jsou popsány v dokumentaci o include().

require() a include() jsou totožné, kromě toho, jak zpracovávají chyby. include() vyprodukuje Warning (varování), zatímco require() skončí s chybou typu Fatal Error (velmi vážná chyba). Jinak řečeno, nerozpakujte se použít require(), pokud chcete, aby nepřítomnost souboru zastavila zpracování stránky. include() se takto nechová, skript bude nerušeně pokračovat. Ujistěte se také, že máte v pořádku nastavení include_path.

Příklad 12-2. Základní příklady použití require()

<?php require 'prepend.php'; require $somefile; require ('somefile.txt'); ?>

Další příklady -- viz dokumentace include().

Poznámka: U verzí před PHP 4.0.2 platí toto: require() se vždy pokusí přečíst příslušný soubor, kromě případu, že se řádek s tímto příkazem nemůže nikdy provést. Podmíněný výraz require() neovlivňuje. Avšak pokud se řádek, na kterém require() leží, vůbec neprovádí, nebude se provádět ani kód v příslušném souboru. Podobně je tomu i v případě cyklů -- ani ty neovlivňují chování require(). Přestože kód obsažený ve vkládaném souboru je stále předmětem opakování, samotné require() se provede pouze jednou.

Viz také include(), require_once(), include_once(), eval(), file(), readfile(), virtual() a include_path.

include()

Konstrukt include() vloží a ohodnotí specifikovaný soubor.

Níže popsané platí i pro require(). Tyto dva konstrukty jsou zcela totožné, kromě toho, jak zpracovávají chyby. include() produkuje Warning (varování), zatímco require() skončí s chybou typu Fatal Error. Jinými slovy, require() použijte tehdy, chcete-li, aby se při chybějícím souboru zastavilo zpracovávání. include() se tak nechová, skript bude nerušeně pokračovat. Ujistěte se také, že máte v pořádku nastavení include_path.

Pokud se vloží soubor, potom kód v něm obsažený dědí kontext proměnné řádku, kde byl vložen. Všechny proměnné dostupné na tomto řádku volajícího souboru budou (od této chvíle) dostupné i ve volaném souboru.

Příklad 12-3. Základní příklad -- include()

vars.php <?php $color = 'zelené'; $fruit = 'jablko'; ?> test.php <?php echo "Vidím $color $fruit"; // Vidím include 'vars.php'; echo "Vidím $color $fruit"; // Vidím zelené jablko ?>

Pokud ke vložení dojde uvnitř funkce ve volajícím souboru, potom se všechen kód obsažený ve volaném souboru bude chovat, jako by byl definován uvnitř této funkce -- tedy v rámci kontextu proměnných funkce.

Příklad 12-4. Vkládání uvnitř funkcí

<?php function foo() { global $color; include 'vars.php'; echo "Vidím $color $fruit"; } /* vars.php je v kontextu foo(), takže * * $fruit NENÍ dostupná mimo tento kontext. * * Naopak $color JE, protože je deklarována * * jako globální. */ foo(); // Vidím zelené jablko echo "Vidím $color $fruit"; // Vidím zelené ?>

Při vkládání souboru přejde parsing na začátku souboru z PHP režimu do módu HTML a na jeho konci se vrací zpět do módu PHP. Z tohoho důvodu musí být prováděný PHP kód ve vkládaném souboru uzavřen mezi platnou počáteční a koncovou PHP značku.

Pokud jsou v PHP povoleny "URL fopen wrappery" (což tak implicitně je), můžete specifikovat soubor ke vložení pomocí URL (přes HTTP) namísto lokálního umístění. Pokud přískušný server interpretuje požadovaný soubor jako PHP kód, proměnné mohou být odkazovány pomocí řetězce URL požadavku jako u HTTP GET. Není to úplně totéž jako vložení souboru s děděním kontextu proměnných od rodičovského souboru; skript běží na vzdáleném serveru a výsledek se potom vloží do lokálního skriptu.

Příklad 12-5. include() přes HTTP

<?php /* Tento příklad předpokládá, že www.example.com je konfigurován k parsování * * souborů .php a nikoli souborů .txt. Tedy, 'funguje' zde znamená, že * * proměnné $foo a $bar jsou dostupné uvnitř vkládaného souboru. */ // Nefunguje; file.txt nebyl na www.example.com zpracován jako PHP include 'http://www.example.com/file.txt?foo=1&bar=2'; // Nefunguje; hledá soubor 'file.php?foo=1&bar=2' v lokálním systému souborů. include 'file.php?foo=1&bar=2'; // Funguje. include 'http://www.example.com/file.php?foo=1&bar=2'; $foo = 1; $bar = 2; include 'file.txt'; // Funguje. include 'file.php'; // Funguje. ?>
Související informace -- viz také Vzdálené soubory, fopen() a file().

Protože include() a require() jsou speciální jazykové konstrukty, pokud se provádějí podmíněně, musíte je uzavřít do bloku.

Příklad 12-6. include() a podmíněné bloky

<?php // Toto je ŠPATNĚ a (jak bylo řečeno) nebude to fungovat. if ($condition) include $file; else include $other; // Tohle je SPRÁVNĚ. if ($condition) { include $file; } else { include $other; } ?>

Obsluha návratů: Uvnitř vkládaného souboru lze provést konstrukt return() k ukončení provádění souboru a návrat do volajícího skriptu. Je tedy možné z vložených souborů vracet hodnoty. Můžete vzít hodnotu volání include, jako by to byla normální funkce.

Poznámka: V PHP 3 se return nesmí objevit uvnitř bloku, pokud to není funkční blok; tehdy však se však return() týká této funkce a ne celého souboru.

Příklad 12-7. include() a konstrukt return()

return.php <?php $var = 'PHP'; return $var; ?> noreturn.php <?php $var = 'PHP'; ?> testreturns.php <?php $foo = include 'return.php'; echo $foo; // vypíše 'PHP' $bar = include 'noreturn.php'; echo $bar; // vypíše 1 ?>

$bar má hodnotu 1, protože příkaz include byl úspěšný. Všimněte si rozdílu mezi výše uvedenými příklady. První používá ve vkládaném souboru return(), druhý nikoli. Dalšími způsoby, jak přiřadit hodnotu souboru do proměnné, jsou funkce fopen(), file() a použití include() společně s funkcemi řízení výstupu.

Viz také require(), require_once(), include_once(), readfile(), virtual(), a include_path.

require_once()

Konstrukt require_once() vloží a ohodnotí specifikovaný soubor během provádění skriptu. Chová se tedy podobně jako require(), s tím rozdílem, že pokud už byl kód ze souboru dříve vložen do skriptu, nebude znovu vkládán. Více informací o chování příkazu -- viz příkaz require().

Příkaz require_once() by se měl používat v případech, kde by mohl být během provádění skriptu tentýž soubor vložen a ohodnocen víckrát, a přitom chcete zajistit právě jedno vložení (je třeba se vyhnout redefinicím funkcí, novému přiřazení hodnot atd.).

Příklady na použití require_once() a include_once() najdete v kódu PEAR přiloženém v nejnovějších distribucích zdrojových kódů PHP.

Poznámka: Příkaz require_once() byl přidán v PHP 4.0.1pl2.

Viz také: require(), include(), include_once(), get_required_files(), get_included_files(), readfile(), a virtual().

include_once()

Konstrukt include_once() vloží a ohodnotí specifikovaný soubor během provádění skriptu. Chová se tedy podobně jako include() , s tím rozdílem, že pokud už byl kód ze souboru dříve vložen do skriptu, nebude znovu vkládán. Jak název napovídá, bude vložen právě jednou.

Příkaz include_once() by se měl používat v případech, kde by mohl být během provádění skriptu tentýž soubor vložen a ohodnocen víckrát, a přitom chcete zajistit právě jedno vložení (je třeba se vyhnout redefinicím funkcí, novému přiřazení hodnot atd.).

Příklady na použití require_once() and include_once() najdete v kódu PEAR přiloženém v nejnovějších distribucích zdrojových kódů PHP.

Poznámka: Příkaz include_once() byl přidán v PHP 4.0.1pl2.

Viz také include(), require(), require_once(), get_required_files(), get_included_files(), readfile(), a virtual().

Kapitola 13. Funkce

Uživatelsky definované funkce

Funkce může být definována pomocí syntaxe podobné této:

function foo ($arg_1, $arg_2, ..., $arg_n)
{
    echo "Ukázková funkce.\n";
    return $retval;
}

Do funkce může být vložen jakýkoli platný PHP kód, dokonce i definice jiných funkcí a tříd.

V PHP 3 musí být funkce definovány dříve, než je na ně odkazováno. V PHP už tento požadavek neplatí.

PHP nepodporuje přetěžování funkcí, není možné ani oddefinování nebo předefinovaná dříve deklarovaných funkcí.

PHP 3 nepodporuje proměnný počet argumentů funkcí, zatímco implicitní argumenty jsou podporovány (více informací - viz Implicitní hodnoty argumentů). PHP 4 podporuje obojí: více informací - viz Seznam argumentů proměnné délky a reference funkcí func_num_args(), func_get_arg(), a func_get_args().

Argumenty funkcí

Informace mohou být do funkcí předávány přes seznam argumentů, což je seznam proměnných a/nebo konstant oddělených čárkou.

PHP podporuje předávání argumentů hodnotou (implicitní), předávání odkazem, a implicitní hodnoty argumentů. Proměnná délka seznamu argumentů je podporována pouze v PHP 4 a pozdějších; viz Seznam argumentů proměnné délky a reference funkcí func_num_args(), func_get_arg(), a func_get_args(). Podobný efekt může být v PHP 3 dosažen předáním pole argumentů do funkce:

function takes_array($input)
{
    echo "$input[0] + $input[1] = ", $input[0]+$input[1];
}

Předávání argumentů odkazem

Implicitně jsou argumenty funkcí předávány hodnotou (takže když změníte hodnotu argumentu ve funkci, nezmění se mimo funkci). Pokud chcete umožnit funkci modifikovat své argumenty, musíte je předávat odkazem.

Pokud chcete, aby byl argument do funkce předáván vždy odkazem, můžete před název argumentu v definici funkce předřadit ampersand (&):

function add_some_extra(&$string)
{
    $string .= 'a něco navíc.';
}
$str = 'Toto je řetězec ';
add_some_extra($str);
echo $str;    // vypíše 'Toto je řetězec a něco navíc.'

Implicitní hodnoty argumentů

Funkce může ve stylu C++ definovat implicitní hodnoty pro skalární argumenty takto:

function makecoffee ($type = "cappucina")
{
    return "Dělám šálek $type.\n";
}
echo makecoffee ();
echo makecoffee ("espressa");

Výstupem výše uvedeného kódu je:

Dělám šálek cappucina. Dělám šálek espressa.

Implicitní hodnota musí být konstantní výraz, ne (například) proměnná nebo položka třídy.

Uvědomte si, že když používáte implicitní argumenty, jakékoli implicitní hodnoty by měly být na pravé staně neimplicitního argumentu; jinak to nebude pracovat podle očekávání. Uvažujme tento kus kódu:

function makeyogurt ($type = "acidophilus", $flavour)
{
    return "Dělám kelímek jogurtu $type $flavour.\n";
}
 
echo makeyogurt ("malina");   // nebude pracovat podle očekávání

Výstupem uvedeného příkladu bude:

Warning: Missing argument 2 in call to makeyogurt() in /usr/local/etc/httpd/htdocs/php3test/functest.html on line 41 Dělám kelímek jogurtu malina.

A nyní to porovnejme s tímto:

function makeyogurt ($flavour, $type = "acidophilus")
{
    return "Dělám kelímek jogurtu $type $flavour.\n";
}
 
echo makeyogurt ("malina");   // pracuje podle očekávání

Příklad vytiskne:

Dělám kelímek jogurtu acidophilus malina.

Seznam argumentů proměnné délky

PHP 4 má podporu pro seznam argumentů proměnné délky v uživatelských funkcích. Je to opravdu jednoduché, použitím funkcí func_num_args(), func_get_arg(), a func_get_args().

Není třeba žádná zvláštní syntaxe, seznam argumentů může být stále explicitně poskytován definicemi funkcí a bude se chovat jako normálně.

Návratové hodnoty

Hodnoty jsou vraceny pomocí nepovinné klausule return. Může být vracen libovolný typ, včetně seznamů a objektů. Klasule způsobuje, že funkce okamžitě ukončí svůj běh a předá řízení zpět na řádek, odkud byla volána. Pro více informací viz return().

function square ($num)
{
    return $num * $num;
}
echo square (4);   // vypíše '16'.

Z funkce nemůžete vracet více hodnot, ale podobného výsledku může být dosaženo vrácením seznamu.

function small_numbers()
{
    return array (0, 1, 2);
}
list ($zero, $one, $two) = small_numbers();

K vrácení odkazu z funkce musíte použít referenční operátor & jak v deklaraci funkce, tak při přiřazování vrácené hodnoty do proměnné:

function &returns_reference()
{
    return $someref;
}

$newref =& returns_reference();

Pro další informace o odkazech se laskavě podívejte na Vysvětlení odkazů.

`old_function`

Klausule old_function umožňuje deklarovat funkci s identickou syntaxí jako v PHP/FI2 (kromě toho, že musíte 'function' nahradit 'old_function'.

Toto je zavržená možnost a měla by být používána pouze PHP/FI2->PHP 3 konvertorem.

Varování

Funkce deklarované jako old_function nelze volat z interního kódu PHP. To mj. znamená, že je nemůžete používat ve funkcích jako usort(), array_walk(), a register_shutdown_function(). Toto omezení můžete obejít napsáním wrapperu (v normální PHP 3 formě), z něhož voláte old_function.

Funkce v proměnných

PHP podporuje koncept funkcí v proměnných. To znamená, že když má název proměnné připojeny závorky, PHP bude hledat funkci se stejným názvem, jako má hodnota proměnné, a pokusí se ji provést. To lze mj. použít k implementací zpětných volání, tabulek funkcí atd.

Funkce v proměnných nebudou fungovat s jazykovými konstrukty jinými než print(), jako je echo(), unset(), isset() a empty(). To je jeden z velkých rozdílů mezi funkcemi PHP a jazykovými konstrukty.

Příklad 13-1. Příklad na funkce v proměnných

<?php function foo() { echo "V foo()<br>\n"; } function bar($arg = '') { echo "V bar(); byl argument '$arg'.<br>\n"; } $func = 'foo'; $func(); $func = 'bar'; $func('test'); ?>

Kapitola 14. Classes and Objects

`class`

A class is a collection of variables and functions working with these variables. A class is defined using the following syntax:

<?php
class Cart
{
    var $items;  // Items in our shopping cart
   
    // Add $num articles of $artnr to the cart
 
    function add_item ($artnr, $num)
    {
        $this->items[$artnr] += $num;
    }
   
    // Take $num articles of $artnr out of the cart
 
    function remove_item ($artnr, $num)
    {
        if ($this->items[$artnr] > $num) {
            $this->items[$artnr] -= $num;
            return true;
        } else {
            return false;
        }   
    }
}
?>

This defines a class named Cart that consists of an associative array of articles in the cart and two functions to add and remove items from this cart.

Výstraha

The following cautionary notes are valid for PHP 4.

The name stdClass is used interally by Zend and is reserved. You cannot have a class named stdClass in PHP.

The function names __sleep and __wakeup are magical in PHP classes. You cannot have functions with these names in any of your classes unless you want the magic functionality associated with them. See below for more information.

PHP reserves all function names starting with __ as magical. It is recommended that you do not use function names with __ in PHP unless you want some documented magic functionality.

Poznámka: In PHP 4, only constant initializers for var variables are allowed. To initialize variables with non-constant values, you need an initialization function which is called automatically when an object is being constructed from the class. Such a function is called a constructor (see below).
<?php
/* None of these will work in PHP 4. */
class Cart
{
    var $todays_date = date("Y-m-d");
    var $name = $firstname;
    var $owner = 'Fred ' . 'Jones';
    var $items = array("VCR", "TV");
}

/* This is how it should be done. */
class Cart
{
    var $todays_date;
    var $name;
    var $owner;
    var $items;

    function Cart()
    {
        $this->todays_date = date("Y-m-d");
        $this->name = $GLOBALS['firstname'];
        /* etc. . . */
    }
}
?>

Classes are types, that is, they are blueprints for actual variables. You have to create a variable of the desired type with the new operator.

<?php
$cart = new Cart;
$cart->add_item("10", 1);

$another_cart = new Cart;
$another_cart->add_item("0815", 3);

This creates the objects $cart and $another_cart, both of the class Cart. The function add_item() of the $cart object is being called to add 1 item of article number 10 to the $cart. 3 items of article number 0815 are being added to $another_cart.

Both, $cart and $another_cart, have functions add_item(), remove_item() and a variable items. These are distinct functions and variables. You can think of the objects as something similar to directories in a filesystem. In a filesystem you can have two different files README.TXT, as long as they are in different directories. Just like with directories where you'll have to type the full pathname in order to reach each file from the toplevel directory, you have to specify the complete name of the function you want to call: In PHP terms, the toplevel directory would be the global namespace, and the pathname separator would be ->. Thus, the names $cart->items and $another_cart->items name two different variables. Note that the variable is named $cart->items, not $cart->$items, that is, a variable name in PHP has only a single dollar sign.

// correct, single $
$cart->items = array("10" => 1); 

// invalid, because $cart->$items becomes $cart->""
$cart->$items = array("10" => 1);

// correct, but may or may not be what was intended:
// $cart->$myvar becomes $cart->items
$myvar = 'items';
$cart->$myvar = array("10" => 1);

Within a class definition, you do not know under which name the object will be accessible in your program: at the time the Cart class was written, it was unknown that the object will be named $cart or $another_cart later. Thus, you cannot write $cart->items within the Cart class itself. Instead, in order to be able to access it's own functions and variables from within a class, one can use the pseudo-variable $this which can be read as 'my own' or 'current object'. Thus, '$this->items[$artnr] += $num' can be read as 'add $num to the $artnr counter of my own items array' or 'add $num to the $artnr counter of the items array within the current object'.

Poznámka: There are some nice functions to handle classes and objects. You might want to take a look at the Class/Object Functions

`extends`

Often you need classes with similar variables and functions to another existing class. In fact, it is good practice to define a generic class which can be used in all your projects and adapt this class for the needs of each of your specific projects. To facilitate this, classes can be extensions of other classes. The extended or derived class has all variables and functions of the base class (this is called 'inheritance' despite the fact that nobody died) and what you add in the extended definition. It is not possible to substract from a class, that is, to undefine any existing functions or variables. An extended class is always dependent on a single base class, that is, multiple inheritance is not supported. Classes are extended using the keyword 'extends'.

class Named_Cart extends Cart
{
    var $owner;
  
    function set_owner ($name)
    {
        $this->owner = $name;
    }
}

This defines a class Named_Cart that has all variables and functions of Cart plus an additional variable $owner and an additional function set_owner(). You create a named cart the usual way and can now set and get the carts owner. You can still use normal cart functions on named carts:

$ncart = new Named_Cart;    // Create a named cart
$ncart->set_owner("kris");  // Name that cart
print $ncart->owner;        // print the cart owners name
$ncart->add_item("10", 1);  // (inherited functionality from cart)

This is also called a "parent-child" relationship. You create a class, parent, and use extends to create a new class based on the parent class: the child class. You can even use this new child class and create another class based on this child class.

Poznámka: Classes must be defined before they are used! If you want the class Named_Cart to extend the class Cart, you will have to define the class Cart first. If you want to create another class called Yellow_named_cart based on the class Named_Cart you have to define Named_Cart first. To make it short: the order in which the classes are defined is important.

`Constructors`

Výstraha

In PHP 3 and PHP 4 constructors behave differently. The PHP 4 semantics are strongly preferred.

Constructors are functions in a class that are automatically called when you create a new instance of a class with new. In PHP 3, a function becomes a constructor when it has the same name as the class. In PHP 4, a function becomes a constructor, when it has the same name as the class it is defined in - the difference is subtle, but crucial (see below).

// Works in PHP 3 and PHP 4.
class Auto_Cart extends Cart
{
    function Auto_Cart()
    {
        $this->add_item ("10", 1);
    }
}

This defines a class Auto_Cart that is a Cart plus a constructor which initializes the cart with one item of article number "10" each time a new Auto_Cart is being made with "new". Constructors can take arguments and these arguments can be optional, which makes them much more useful. To be able to still use the class without parameters, all parameters to constructors should be made optional by providing default values.

// Works in PHP 3 and PHP 4.
class Constructor_Cart extends Cart
{
    function Constructor_Cart($item = "10", $num = 1)
    {
        $this->add_item ($item, $num);
    }
}
 
// Shop the same old boring stuff.
 
$default_cart = new Constructor_Cart;
 
// Shop for real...
 
$different_cart = new Constructor_Cart("20", 17);

You also can use the @ operator to mute errors occuring in the constructor, e.g. @new.

Výstraha

In PHP 3, derived classes and constructors have a number of limitations. The following examples should be read carefully to understand these limitations.

class A
{
    function A()
    {
      echo "I am the constructor of A.<br>\n";
    }
}

class B extends A
{
    function C()
    {
        echo "I am a regular function.<br>\n";
    }
}

// no constructor is being called in PHP 3.
$b = new B;

In PHP 3, no constructor is being called in the above example. The rule in PHP 3 is: 'A constructor is a function of the same name as the class.'. The name of the class is B, and there is no function called B() in class B. Nothing happens.

This is fixed in PHP 4 by introducing another rule: If a class has no constructor, the constructor of the base class is being called, if it exists. The above example would have printed 'I am the constructor of A.<br>' in PHP 4.

class A
{
    function A()
    {
        echo "I am the constructor of A.<br>\n";
    }

    function B()
    {
        echo "I am a regular function named B in class A.<br>\n";
        echo "I am not a constructor in A.<br>\n";
    }
}

class B extends A
{
    function C()
    {
        echo "I am a regular function.<br>\n";
    }
}

// This will call B() as a constructor.
$b = new B;

In PHP 3, the function B() in class A will suddenly become a constructor in class B, although it was never intended to be. The rule in PHP 3 is: 'A constructor is a function of the same name as the class.'. PHP 3 does not care if the function is being defined in class B, or if it has been inherited.

This is fixed in PHP 4 by modifying the rule to: 'A constructor is a function of the same name as the class it is being defined in.'. Thus in PHP 4, the class B would have no constructor function of its own and the constructor of the base class would have been called, printing 'I am the constructor of A.<br>'.

Výstraha

Neither PHP 3 nor PHP 4 call constructors of the base class automatically from a constructor of a derived class. It is your responsibility to propagate the call to constructors upstream where appropriate.

Poznámka: There are no destructors in PHP 3 or PHP 4. You may use register_shutdown_function() instead to simulate most effects of destructors.

Destructors are functions that are called automatically when an object is destroyed, either with unset() or by simply going out of scope. There are no destructors in PHP.

`::`

Výstraha

The following is valid for PHP 4 only.

Sometimes it is useful to refer to functions and variables in base classes or to refer to functions in classes that have not yet any instances. The :: operator is being used for this.

class A
{
    function example()
    {
        echo "I am the original function A::example().<br>\n";
    }
}

class B extends A
{
    function example()
    {
        echo "I am the redefined function B::example().<br>\n";
        A::example();
    }
}

// there is no object of class A.
// this will print
//   I am the original function A::example().<br>
A::example();

// create an object of class B.
$b = new B;

// this will print 
//   I am the redefined function B::example().<br>
//   I am the original function A::example().<br>
$b->example();

The above example calls the function example() in class A, but there is no object of class A, so that we cannot write $a->example() or similar. Instead we call example() as a 'class function', that is, as a function of the class itself, not any object of that class.

There are class functions, but there are no class variables. In fact, there is no object at all at the time of the call. Thus, a class function may not use any object variables (but it can use local and global variables), and it may no use $this at all.

In the above example, class B redefines the function example(). The original definition in class A is shadowed and no longer available, unless you are refering specifically to the implementation of example() in class A using the ::-operator. Write A::example() to do this (in fact, you should be writing parent::example(), as shown in the next section).

In this context, there is a current object and it may have object variables. Thus, when used from WITHIN an object function, you may use $this and object variables.

`parent`

You may find yourself writing code that refers to variables and functions in base classes. This is particularly true if your derived class is a refinement or specialisation of code in your base class.

Instead of using the literal name of the base class in your code, you should be using the special name parent, which refers to the name of your base class as given in the extends declation of your class. By doing this, you avoid using the name of your base class in more than one place. Should your inheritance tree change during implementation, the change is easily made by simply changing the extends declaration of your class.

class A
{
    function example()
    {
        echo "I am A::example() and provide basic functionality.<br>\n";
    }
}

class B extends A
{
    function example()
    {
        echo "I am B::example() and provide additional functionality.<br>\n";
        parent::example();
    }
}

$b = new B;

// This will call B::example(), which will in turn call A::example().
$b->example();

Serializing objects - objects in sessions

Poznámka: In PHP 3, objects will lose their class association throughout the process of serialization and unserialization. The resulting variable is of type object, but has no class and no methods, thus it is pretty useless (it has become just like an array with a funny syntax).

Výstraha

The following information is valid for PHP 4 only.

serialize() returns a string containing a byte-stream representation of any value that can be stored in PHP. unserialize() can use this string to recreate the original variable values. Using serialize to save an object will save all variables in an object. The functions in an object will not be saved, only the name of the class.

In order to be able to unserialize() an object, the class of that object needs to be defined. That is, if you have an object $a of class A on page1.php and serialize this, you'll get a string that refers to class A and contains all values of variabled contained in $a. If you want to be able to unserialize this on page2.php, recreating $a of class A, the definition of class A must be present in page2.php. This can be done for example by storing the class defintion of class A in an include file and including this file in both page1.php and page2.php.

classa.inc:
  class A 
  {
      var $one = 1;
    
      function show_one()
      {
          echo $this->one;
      }
  }
  
page1.php:
  include("classa.inc");
  
  $a = new A;
  $s = serialize($a);
  // store $s somewhere where page2.php can find it.
  $fp = fopen("store", "w");
  fputs($fp, $s);
  fclose($fp);

page2.php:
  // this is needed for the unserialize to work properly.
  include("classa.inc");

  $s = implode("", @file("store"));
  $a = unserialize($s);

  // now use the function show_one() of the $a object.  
  $a->show_one();

If you are using sessions and use session_register() to register objects, these objects are serialized automatically at the end of each PHP page, and are unserialized automatically on each of the following pages. This basically means that these objects can show up on any of your pages once they become part of your session.

It is strongly recommended that you include the class definitions of all such registered objects on all of your pages, even if you do not actually use these classes on all of your pages. If you don't and an object is being unserialized without its class definition being present, it will lose its class association and become an object of class stdClass without any functions available at all, that is, it will become quite useless.

So if in the example above $a became part of a session by running session_register("a"), you should include the file classa.inc on all of your pages, not only page1.php and page2.php.

The magic functions `sleep` and `wakeup`

serialize() checks if your class has a function with the magic name __sleep. If so, that function is being run prior to any serialization. It can clean up the object and is supposed to return an array with the names of all variables of that object that should be serialized.

The intended use of __sleep is to close any database connections that object may have, committing pending data or perform similar cleanup tasks. Also, the function is useful if you have very large objects which need not be saved completely.

Conversely, unserialize() checks for the presence of a function with the magic name __wakeup. If present, this function can reconstruct any resources that object may have.

The intended use of __wakeup is to reestablish any database connections that may have been lost during serialization and perform other reinitialization tasks.

References inside the constructor

Creating references within the constructor can lead to confusing results. This tutorial-like section helps you to avoid problems.

class Foo
{
    function Foo($name)
    {
        // create a reference inside the global array $globalref
        global $globalref;
        $globalref[] = &$this;
        // set name to passed value
        $this->setName($name);
        // and put it out
        $this->echoName();
    }

    function echoName()
    {
        echo "<br>",$this->name;
    }
	
    function setName($name)
    {
        $this->name = $name;
    }
}

Let us check out if there is a difference between $bar1 which has been created using the copy = operator and $bar2 which has been created using the reference =& operator...

$bar1 = new Foo('set in constructor');
$bar1->echoName();
$globalref[0]->echoName();

/* output:
set in constructor
set in constructor
set in constructor */

$bar2 =& new Foo('set in constructor');
$bar2->echoName();
$globalref[1]->echoName();

/* output:
set in constructor
set in constructor
set in constructor */

Apparently there is no difference, but in fact there is a very significant one: $bar1 and $globalref[0] are _NOT_ referenced, they are NOT the same variable. This is because "new" does not return a reference by default, instead it returns a copy.

Poznámka: There is no performance loss (since PHP 4 and up use reference counting) returning copies instead of references. On the contrary it is most often better to simply work with copies instead of references, because creating references takes some time where creating copies virtually takes no time (unless none of them is a large array or object and one of them gets changed and the other(s) one(s) subsequently, then it would be wise to use references to change them all concurrently).

To prove what is written above let us watch the code below.

// now we will change the name. what do you expect?
// you could expect that both $bar1 and $globalref[0] change their names...
$bar1->setName('set from outside');

// as mentioned before this is not the case.
$bar1->echoName();
$globalref[0]->echoName();

/* output:
set from outside
set in constructor */

// let us see what is different with $bar2 and $globalref[1]
$bar2->setName('set from outside');

// luckily they are not only equal, they are the same variable
// thus $bar2->name and $globalref[1]->name are the same too
$bar2->echoName();
$globalref[1]->echoName();

/* output:
set from outside
set from outside */

Another final example, try to understand it.

class A
{
    function A($i)
    {
        $this->value = $i;
        // try to figure out why we do not need a reference here
        $this->b = new B($this);
    }

    function createRef()
    {
        $this->c = new B($this);
    }

    function echoValue()
    {
        echo "<br>","class ",get_class($this),': ',$this->value;
    }
}


class B
{
    function B(&$a)
    {
        $this->a = &$a;
    }

    function echoValue()
    {
        echo "<br>","class ",get_class($this),': ',$this->a->value;
    }
}

// try to undestand why using a simple copy here would yield
// in an undesired result in the *-marked line
$a =& new A(10);
$a->createRef();

$a->echoValue();
$a->b->echoValue();
$a->c->echoValue();

$a->value = 11;

$a->echoValue();
$a->b->echoValue(); // *
$a->c->echoValue();

/*
output:
class A: 10
class B: 10
class B: 10
class A: 11
class B: 11
class B: 11
*/

Kapitola 15. Vysvětlení referencí (odkazů)

Co jsou reference

Reference (odkazy) jsou prostředek, jak v PHP přistupovat k témuž obsahu proměnné pod různými jmény. Nejsou to ukazatele (pointery) jako v C, jsou to aliasy v tabulce symbolů. Uvědomte si, že v PHP je rozdíl mezi názvem proměnné a jejím obsahem, takže stejný obsah může mít různé názvy. Nejbližší analogií jsou názvy souborů a soubory v UNIXu - názvy proměnných jsou položky adresáře, obsahy proměnných samotné soubory. Na reference může být nazíráno jako na hardlinky v UNIXovém systému souborů.

Co reference dělají

PHP reference umožňují zajistit, aby dvě proměnné odkazovaly na tentýž obsah. Tzn. když provedete:

$a =& $b

znamená to, že $a a $b ukazují na stejnou proměnnou.

Poznámka: $a a $b jsou zde úplně ekvivalentní, tj. nikoliv že $a ukazuje na $b apod., nýbrž že $a a $b ukazují na stejné místo.

Stejná syntaxe se může použít s funkcemi, které vrací reference a s operátorem new (v PHP 4.0.4 a pozdějších):

$bar =& new fooclass();
$foo =& find_var ($bar);

Poznámka: Nepoužití operátoru & způsobí zkopírování objektu. Když ve třídě použijete $this, bude se pracovat s aktuální instancí třídy. Přiřazení bez & zkopíruje instanci (např. objektu) a $this bude pracovat s touto kopií, což není vždy to, co se požaduje. Většinou chcete mít jedinou instanci, s níž budete pracovat, kvůli rychlosti a alokaci paměti.

Druhou věcí, kterou reference dělají, je předávání proměnných odkazem. To se dělá vytvořením lokální proměnné ve funkci a proměnné v kontextu volajícího prostředí, kdy se odkazuje na tentýž obsah. Například:

function foo (&$var)
{
    $var++;
}

$a=5;
foo ($a);

nastaví do $a hodnotu 6. To proto, že ve funkci foo proměnná $var odkazuje tentýž obsah jako $a. Viz detailnější vysvětlení o předávání odkazem.

Třetí věcí, kterou mohou reference dělat, je vracení přes reference.

Co reference nejsou

Jak již bylo řečeno, reference nejsou ukazatele. To znamená, že tento konstrukt nebude dělat to, co očekáváte:

function foo (&$var)
{
    $var =& $GLOBALS["baz"];
}
foo($bar);

Nastane to, že $var ve funkci foo bude přiřazena $bar ve volajícím kontextu, avšak poté bude přiřazena $GLOBALS["baz"]. Není způsob, jak přiřadit $bar ve volajícím kontextu něčemu jinému za použití mechanismu referencí, protože $bar není ve funkci foo dostupná (je reprezentována $var, ale $var má pouze obsah a nikoli spojení názvu s hodnotou v tabulce symbolů).

Předávání referencí (odkazem)

Můžete předávat proměnnou do funkce pomocí odkazu, takže funkce může modifikovat její argumenty. Syntaxe je následující:

function foo (&$var)
{
    $var++;
}

$a=5;
foo ($a);
// $a je teď 6

Všimněte si, že ve volání funkce není znak reference - pouze v její definici. Samotná definice funkce stačí na správné předávání argumentu odkazem.

Následující věci lze předávat referencí:

Proměnná, např. foo($a)
Konstrukt s new, např. foo(new foobar())
Reference, vracená z funkce, např.:
function &bar() { $a = 5; return $a; } foo(bar());
Viz také vysvětlení vracení přes reference.

Žádné jiné výrazy nemohou být předávány odkazem, výsledek tohoto není definován. Například, následující ukázky předávání odkazem jsou neplatné:

function bar() // Všimněte si chybějícího &
{
    $a = 5;
    return $a;
}
foo(bar());

foo($a = 5) // Výraz, nikoli proměnná
foo(5) // Konstanta, nikoli proměnná

Tyto požadavky platí pro PHP 4.0.4 a pozdější.

Vracení referencí

Vracení odkazem je užitečné, když chcete použít funkci k nalezení proměnné, která by měla být odkazu přiřazena. Při vracení referencí použijte tuto syntaxi:

function &find_var ($param)
{
    ...nějaký kód...
    return $found_var;
}

$foo =& find_var ($bar);
$foo->x = 2;

V tomto příkladu by bylo funkcí find_var nastaveno vlastnictví téhož objektu, nikoli jeho kopie, jak by se stalo bez použití syntaxe bez odkazů.

Poznámka: Narozdíl od předávání parametru, zde musíte & použít na obou místech - k indikaci, že vracíte odkaz a nikoli kopii jako obvykle, a k indikaci přiřazení reference do $foo namísto běžného přiřazení (hodnoty).

Odnastavení odkazů

Když odnastavíte referenci, přerušíte vazbu mezi názvem proměnné a jejím obsahem. To neznamená, že by obsah byl zničen. Například:

$a = 1;
$b =& $a;
unset ($a);

neodnastaví $b, nýbrž pouze $a.

Znovu je dobré si připomenout analogii s UNIXovým příkazem unlink.

Další výskyt referencí

Mnoho syntaktických konstruktů v PHP je implementováno přes odkazový mechanismus, takže vše, co bylo řečeno výše o přiřazování referencí, platí i na tyto konstrukty. Některé konstrukty, jako předávání a vracení přes odkazy, byly již zmíněny. Ostatní konstrukty používající reference jsou:

odkazy `global`

Když deklarujete proměnnou jako global $var, ve skutečnosti vytváříte odkaz na globální proměnnou. Tzn. je to totéž, jako:

$var =& $GLOBALS["var"];

To znamená, například, že odnastavení $var neodnastaví globální proměnnou.

`$this`

V metodě objektu je $this vždy odkazem na volající objekt.

III. Vlastnosti

Obsah
16. Zpracování chyb
17. Tvorba a úpravy obrázků
18. HTTP autentikace a PHP
19. Cookies
20. Zpracování uploadu souborů
21. Použití vzdálených souborů
22. Obsluha spojení
23. Persistentní databázová spojení
24. Bezpečný režim
25. Using PHP from the command line

Kapitola 16. Zpracování chyb

V PHP existuje několik druhů chyb a varování. Jsou to:

Tabulka 16-1. Druhy chyb v PHP

Hodnota	Konstanta	Popis	Poznámka
1	E_ERROR	významné (fatální) runtimové chyby
2	E_WARNING	runtimová varování (nevýznamné chyby)
4	E_PARSE	kompilační syntaktické chyby
8	E_NOTICE	runtimové zprávy (méně vážné než varování)
16	E_CORE_ERROR	fatální chyby, které se vyskytly během startu PHP	pouze PHP 4
32	E_CORE_WARNING	varování během startu PHP	pouze PHP 4
64	E_COMPILE_ERROR	fatální kompilační chyby	pouze PHP 4
128	E_COMPILE_WARNING	kompilační varování (nevýznamné chyby)	PHP 4 only
256	E_USER_ERROR	uživatelsky generované chybové zprávy	PHP 4 only
512	E_USER_WARNING	uživatelsky generovaná varování	PHP 4 only
1024	E_USER_NOTICE	uživatelsky generované informativní zprávy	PHP 4 only
	E_ALL	všechny z uvedených, které jsou danou verzí PHP podporovány

Výše uvedené hodnoty (ať již číselné nebo symbolické) se používají pro sestavení bitové masky, která specifikuje, které chyby se mají oznamovat. Můžete používat bitové logické operátory pro kombinaci hodnot nebo maskování určitých druhů chyb. Uvědomte si, že v souboru php.ini budou správně interpretovány pouze operátory '|', '~', '!', a '&', a že v php3.ini nelze použít žádné z těchto operátorů.

V PHP 4 je jako implicitní hodnota pro error_reporting nastaveno E_ALL & ~E_NOTICE, tzn. hlášení všech chyb a varování, které nejsou na úrovni E_NOTICE. V PHP 3 je implicitní (E_ERROR | E_WARNING | E_PARSE), což znamená totéž. Uvědomte si, že v souboru php3.ini nelze používat konstanty, a proto nastavení error_reporting musí být numerické; tedy například 7.

Iniciální nastavení může být v ini souboru změněno direktivou error_reporting, v serveru Apache v souboru httpd.conf direktivou php_error_reporting (php3_error_reporting v PHP 3), a konečně může být též nastaveno skriptem za použití funkce error_reporting().

Varování

Pokud upgradujete kód nebo server z PHP 3 na PHP 4, měli byste ověřit tato nastavení a volání error_reporting() anebo potlačit hlášení nových typů chyb, zvláště E_COMPILE_ERROR. To může vést k vyprázdnění obsahu dokumentů bez jakékoli informace o tom, co se stalo a kde hledat problém.

Všechny PHP výrazy mohou být také volány s prefixem "@", který vypíná hlášení chyb pro tento jediný výraz. Pokud během provádění výrazu nastane chyba a volba track_errors je zapnutá, najdete chybovou zprávu v globální proměnné $php_errormsg.

Poznámka: Prefixovým operátorem řízení chyb @ nelze potlačit chybová hlášení o syntaktických chybách.

Varování

V současnosti prefixový operátor řízení chyb v případě kritických chyb (které ukončí provádění skriptu) pouze potlačí chybové hlášení. Jinými slovy, pokud použijete @ k potlačení chyb z jisté funkce, která není dostupná nebo byla chybně zapsána, skript zde skončí, aniž by indikoval proč.

Níže uvedený příklad ukazuje použití schopností zpracování chyb v PHP. Definujeme funkci zpracování chyb, která zaznamenává informace do souboru (v XML formátu) a v případě kritické chyby odešle e-mailovou zprávu vývojáři.

Příklad 16-1. Použití zpracování chyb ve skriptu

<?php // uděláme si vlastní zpacování chyb error_reporting(0); // uživatelsky definovaná funkce pro zpracování chyb function userErrorHandler ($errno, $errmsg, $filename, $linenum, $vars) { // časové razítko položky $dt = date("Y-m-d H:i:s (T)"); // definuje asociativní pole pro chybový řetězec // ve skutečnosti mohou položky obsahovat pouze // hodnoty 2,8,256,512 a 1024 $errortype = array ( 1 => "Error", 2 => "Warning", 4 => "Parsing Error", 8 => "Notice", 16 => "Core Error", 32 => "Core Warning", 64 => "Compile Error", 128 => "Compile Warning", 256 => "User Error", 512 => "User Warning", 1024=> "User Notice" ); // množina chyb, pro které bude uložen výpis proměnných $user_errors = array(E_USER_ERROR, E_USER_WARNING, E_USER_NOTICE); $err = "<errorentry>\n"; $err .= "\t<datetime>".$dt."</datetime>\n"; $err .= "\t<errornum>".$errno."</errornum>\n"; $err .= "\t<errortype>".$errortype[$errno]."</errortype>\n"; $err .= "\t<errormsg>".$errmsg."</errormsg>\n"; $err .= "\t<scriptname>".$filename."</scriptname>\n"; $err .= "\t<scriptlinenum>".$linenum."</scriptlinenum>\n"; if (in_array($errno, $user_errors)) $err .= "\t<vartrace>".wddx_serialize_value($vars,"Variables")."</vartrace>\n"; $err .= "</errorentry>\n\n"; // pro testování // echo $err; // ulož do chybového protokolu a pošli mi zprávu (pokud je to kritická chyba) error_log($err, 3, "/usr/local/php4/error.log"); if ($errno == E_USER_ERROR) mail("phpdev@mydomain.com","Critical User Error",$err); } function distance ($vect1, $vect2) { if (!is_array($vect1) || !is_array($vect2)) { trigger_error("Incorrect parameters, arrays expected", E_USER_ERROR); return NULL; } if (count($vect1) != count($vect2)) { trigger_error("Vectors need to be of the same size", E_USER_ERROR); return NULL; } for ($i=0; $i<count($vect1); $i++) { $c1 = $vect1[$i]; $c2 = $vect2[$i]; $d = 0.0; if (!is_numeric($c1)) { trigger_error("Coordinate $i in vector 1 is not a number, using zero", E_USER_WARNING); $c1 = 0.0; } if (!is_numeric($c2)) { trigger_error("Coordinate $i in vector 2 is not a number, using zero", E_USER_WARNING); $c2 = 0.0; } $d += $c2*$c2 - $c1*$c1; } return sqrt($d); } $old_error_handler = set_error_handler("userErrorHandler"); // nedefinovaná konstanta, generuje varování $t = I_AM_NOT_DEFINED; // definuje nějaké "vektory" $a = array(2,3,"foo"); $b = array(5.5, 4.3, -1.6); $c = array (1,-3); // generuje uživatelskou chybu $t1 = distance($c,$b)."\n"; // generuje jinou uživatelskou chybu $t2 = distance($b,"i am not an array")."\n"; // generuje hlášení $t3 = distance($a,$b)."\n"; ?>
Toto je pouze jednoduchý příklad, který ukazuje, jak používat Funkce pro zpracování a záznam chyb.

Viz také error_reporting(), error_log(), set_error_handler(), restore_error_handler(), trigger_error(), user_error()

Kapitola 17. Tvorba a úpravy obrázků

PHP není omezeno na tvorbu pouze HTML výstupu. Může také vytvářet a upravovat obrázkové soubory různých formátů, včetně gif, png, jpg, wbmp a xpm. PHP může dokonce přímo posílat obrazové proudy do browseru. Na to budete potřebovat PHP zkompilované s GD knihovnou obrazových funkcí. GD a PHP mohou vyžadovat další knihovny v závislosti na obrazových formátech, se kterými chcete pracovat. GD přestala podporovat gif obrázky ve verzi 1.6.

Příklad 17-1. Tvorba PNG obrázků v PHP

<?php Header("Content-type: image/png"); $string=implode($argv," "); $im = imageCreateFromPng("images/button1.png"); $orange = ImageColorAllocate($im, 220, 210, 60); $px = (imagesx($im)-7.5*strlen($string))/2; ImageString($im,3,$px,9,$string,$orange); ImagePng($im); ImageDestroy($im); ?>
Tento příklad by se volal ze stránky pomocí tagu podobného tomuto: <img src="button.php?text"> Skript button.php pak vezme řetězec "text", překryje jím základní obrázek, což je v tomto případě "images/button1.png" a zobrazí výsledný obrázek. Toto je vhodný způsob jak se vyhnout kreslení nového obrázku tlačítka pokaždé, když chcete změnit text tlačítka. Touto metodou se generují automaticky.

Kapitola 18. HTTP autentikace a PHP

Prostředky HTTP autentikace jsou v PHP přístupné pouze pokud PHP běží jako modul Apache, tudíž nejsou přístupné v CGI verzi. V PHP skriptu běžícím pod modulem Apache lze použít funkci header() k odeslání zprávy "Authentication Required" klientskému browseru, což vyvolá zobrazení dialogového okna pro vložení uživatelského jména a hesla. Jakmile uživatel zadá jméno a heslo, URL obsahující tento PHP skript se zavolá znovu s proměnnými $PHP_AUTH_USER, $PHP_AUTH_PW and $PHP_AUTH_TYPE obsahujícími jméno, heslo a typ autentikace. V současnosti je podporována pouze "Basic" autentikace. Více informací viz funkce header().

Následující fragment kódu může posloužit jako ukázka vyžádání autentikace uživatele na stránce:

Příklad 18-1. Ukázka HTTP Autentikace

<?php if(!isset($PHP_AUTH_USER)) { Header("WWW-Authenticate: Basic realm=\"My Realm\""); Header("HTTP/1.0 401 Unauthorized"); echo "Text, který se odešle, pokud uživatel zmáčkne tlačítko Cancel\n"; exit; } else { echo "Ahoj $PHP_AUTH_USER.<P>"; echo "Jako heslo jsi zadal $PHP_AUTH_PW.<P>"; } ?>

Místo protého vytištění $PHP_AUTH_USER a $PHP_AUTH_PW byste asi chtěli ověřit platnost zadaného jména a hesla. Například dotazem v databázi nebo vyhledáním uživatele v dbm souboru.

Pozor na chybové browsery Internet Explorer. Zdá se, že jsou velice vybíravé, pokud jde o pořadí hlaviček. Zdá se, že odeslání hlavičky WWW-Authenticate před hlavičkou HTTP/1.0 401 zabírá.

Aby se zabránilo psaní skriptů odhalujících hesla na stránkách autentikovaných některým z tradičních externích mechanismů, PHP_AUTH proměnné se nevytvoří, pokud je pro tu kterou stránku zapnuta externí autentikace. V takovém případě můžete k identifikaci externě autentikovaného uživatele použít proměnnou $REMOTE_USER.

Všimněte si nicméně, že výše uvedené nezabrání krádežím hesel z autentikovaných URL osobou, která ovládá neautentikovanou URL na stejném serveru.

Jak Netscape, tak Internet Explorer po přijetí response kódu 401 vyprázdní autentikační cache současného realmu. Tak můžete uživatele v podstatě "odlogovat". Někteří lidé toho využívají k "vypršení" přihlášení nebo tvorbě odhlašovacího tlačítka.

Příklad 18-2. Ukázka HTTP autentikace vyžadující nové jméno a heslo

<?php
  function authenticate() {
    Header( "WWW-Authenticate: Basic realm=\"Test Authentication System\"");
    Header( "HTTP/1.0 401 Unauthorized");
    echo "K přístupu na tento zdroj musíte zadat platné ID a heslo\n";
    exit;
  }
 
  if(!isset($PHP_AUTH_USER) || ($SeenBefore == 1 && !strcmp($OldAuth, $PHP_AUTH_USER)) ) {
   authenticate();
  }
  else {
   echo "Welcome: $PHP_AUTH_USER<BR>";
   echo "Old: $OldAuth";
   echo "<FORM ACTION=\"$PHP_SELF\" METHOD=POST>\n";
   echo "<INPUT TYPE=HIDDEN NAME=\"SeenBefore\" VALUE=\"1\">\n";
   echo "<INPUT TYPE=HIDDEN NAME=\"OldAuth\" VALUE=\"$PHP_AUTH_USER\">\n";
   echo "<INPUT TYPE=Submit VALUE=\"Re Authenticate\">\n";
   echo "</FORM>\n";
  }
?>

Podle standardu HTTP Basic authentication se toto chování nevyžaduje, takže byste na to nikdy neměli spoléhat. Pokusy s Lynxem ukázaly, že Lynx po přijetí response kódu 401 nevyprázdní autentikační údaje, takže po stisknutí back a forward se znovu ukáže požadovaný zdroj (pokud se nezměnily požadavky na údaje).

Dále si všimněte, že tato vlastnost při použití IIS serveru a CGI verze PHP díky omezením IIS nefunguje.

Kapitola 19. Cookies

PHP transparentně podporuje HTTP cookies. Cookies jsou mechanismem na ukládání dat ve vzdáleném browseru a tudíž sledování nebo identifikaci vracejících se uživatelů. Cookies můžete nastavovat pomocí funkce setcookie(). Cookies jsou součástí HTTP hlavičky, tudíž setcookie() se musí volat před odesláním výstupu do browseru. To je stejné omezení, jako má funkce header().

Všechny cookies přijaté od klienta se automaticky stávají PHP proměnnou stejně jako u GET a POST dat. Pokud chcete přiřadit jednomu cookie více hodnot, přidejte [] na konec jména cookie. Více detailů viz funkce setcookie().

Kapitola 20. Zpracování uploadu souborů

Uploading metodou POST

PHP umožňuje zpracování uploadu souborů z jakéhokoli prohlížeče vyhovujícího RFC-1867 (což zahrnuje mj. Netscape Navigator 3 a pozdější, Microsoft Internet Explorer 3 se záplatou od Microsoftu, nebo pozdější bez záplaty). Tato schopnost umožňuje lidem uploadovat textové i binární soubory. S autentizací poskytovanou PHP a s funkcemi pro manipulaci se soubory máte plnou kontrolu nad tím, kdo smí uploadovat a co se má udělat s uploadovaným souborem.

Nezapomeňte, že PHP podporuje také uploady metodou PUT tak, jak se používá v Netscape Composeru a v editoru Amaya od W3C. Pro bližší detaily viz Podpora metody PUT.

Obrazovka pro upload souboru může být tvořena speciálním formulářem, který vypadá podobně jako tento:

Příklad 20-1. Formulář pro upload souboru

<form enctype="multipart/form-data" action="_URL_" method="post"> <input type="hidden" name="MAX_FILE_SIZE" value="1000"> Send this file: <input name="userfile" type="file"> <input type="submit" value="Send File"> </form>
_URL_ by mělo označovat PHP soubor. Skryté pole MAX_FILE_SIZE musí předcházet pole pro vložení souboru a jeho hodnota specifikuje maximální akceptovanou velikost souboru. Hodnota je v bytech.

Varování

Hodnota MAX_FILE_SIZE je z hlediska prohlížeče pouze informativní. Je snadné ji obejít. Takže nepočítejte s tím, že prohlížeč se bude chovat tak, jak si přejete. Nastavení maximální velikosti v PHP však samozřejmě nemůže být obelstěno.

Proměnné definované pro uploadované soubory se liší v závislosti na verzi a konfiguraci PHP. Pokud je aktivní volba track_vars, bude inicializováno pole $HTTP_POST_FILES/$_FILES. Konečně, související proměnné mohou být inicializovány jako globální, pokud je zapnuta volba register_globals. Ovšem používání globálních proměnných není doporučeno. Po úspěšném uploadu budou v cílovém skriptu definovány následující proměnné:

Poznámka: track_vars je od PHP 4.0.3 vždy zapnuto. U PHP 4.1.0 a pozdějších může být použito $_FILES namísto $HTTP_POST_FILES. $_FILES je vždy globální proměnná, takže by se neměla používat specifikace global pro proměnnou $_FILES.

$HTTP_POST_FILES/$_FILES obsahuje informace o uploadovaném souboru.

Obsah $HTTP_POST_FILES je takovýto (uvědomte si, že se předpokládá použití názvu uploadovaného souboru 'userfile' tak, jako v příkladu výše):

$HTTP_POST_FILES['userfile']['name']: Originální název souboru na klientském počítači.
$HTTP_POST_FILES['userfile']['type']: MIME typ souboru, pokud prohlížeč tuto informaci poskytuje (např. "image/gif").
$HTTP_POST_FILES['userfile']['size']: Velikost uploadovaného souboru v bytech.
$HTTP_POST_FILES['userfile']['tmp_name']: Dočasný název souboru, pod nímž byl uploadovaný soubor uložen na server.

Poznámka: PHP 4.1.0 a pozdější podporují zkrácený název proměnné $_FILES. PHP 3 nepodporuje $HTTP_POST_FILES.

Obsah proměnnách v situaci, kdy je proměnná register_globals zapnuta nastavením v souboru php.ini (uvědomte si, že se předpokládá použití názvu uploadovaného souboru 'userfile' tak, jako v příkladu výše):

$userfile - Dočasný název souboru, pod kterým byl uploadovaný soubor uložen na server.
$userfile_name - Originální název souboru nebo cesta na odesílajícím systému.
$userfile_size - Velikost uploadovaného souboru v bytech.
$userfile_type - MIME typ souboru, pokud prohlížeč tuto informaci poskytuje (např. "image/gif").

Uvědomte si, že proměnná "$userfile" ve skutečnosti představuje název pole <input> se specifikací type="file" ve formuláři. Pro výše uvedený příklad jsme zvolili název "userfile".

Poznámka: Nastavení register_globals = On se nedoporučuje z bezpečnostních a výkonnostních důvodů.

Soubory se implicitně ukládají do systémového adresáře pro dočasné soubory, pokud nebylo direktivou upload_tmp_dir v souboru php.ini stanoveno jinak. Systémový adresář pro dočasné soubory může být změněn nastavení proměnné prostředí TMPDIR v prostředí, kde PHP běží. Nastavení za použití putenv() z PHP skriptu nebude fungovat. Tato proměnná prostředí může být také použita k ujištění se, že všechny ostatní operace pracují s uploadovanými soubory.

Příklad 20-2. Ověřování uploadu souboru

Následující příklady jsou pro verze PHP 4 vyšší než PHP 4.0.2. (viz funkce is_uploaded_file() a move_uploaded_file()).

<?php // V PHP 4.1.0 a pozdějších by mělo být použito $_FILES namísto $HTTP_POST_FILES. if (is_uploaded_file($HTTP_POST_FILES['userfile']['tmp_name'])) { copy($HTTP_POST_FILES['userfile']['tmp_name'], "/place/to/put/uploaded/file"); } else { echo "Possible file upload attack. Filename: " . $HTTP_POST_FILES['userfile']['name']; } /* ...or... */ move_uploaded_file($HTTP_POST_FILES['userfile']['tmp_name'], "/place/to/put/uploaded/file"); ?>

PHP skript, který přijímá uploadované soubory, by měl implementovat veškerou logiku pro stanovení, co by se mělo udělat s uploadovaným souborem. Můžete např. použít proměnnou $HTTP_POST_FILES['userfile']['size'] pro zahození souborů, které jsou příliš malé nebo velké. Mohli byste použít také proměnnou $HTTP_POST_FILES['userfile']['type'] pro filtraci souborů podle MIME datového typu. Bez ohledu na řešení, soubor by měl být smazán nebo přesunut jinam.

Soubor bude automaticky smazán z dočasného adresáře na konci skriptu, pokud nebyl přesunut jinam nebo přejmenován.

Častá úskalí

MAX_FILE_SIZE nemůže specifikovat velikost souboru větší než je ta, která byla nastavena pomocí upload_max_filesize v konfiguraci PHP. Implicitně jsou to 2 MB.

Pokud je zapnut limit paměti, může být potřeba větší hodnota memory_limit. Ujistěte se, že je hodnota memory_limit dostatečně velká.

Pokud je nastavená hodnota max_execution_time příliš malá, doba provádění skriptu ji může překročit. Ujistěte se, že je hodnota max_execution_time dostatečně velká.

Pokud je nastavená hodnota post_max_size příliš malá, nemůže být uploadován větší soubor. Ujistěte se, že je hodnota post_max_size dostatečně velká.

Neověřování, se kterým souborem se pracuje, může znamenat, že se uživatelé mohou dostat k citlivým informacím v jiných adresářích.

Uvědomte si prosím, že server CERN httpd odstraňuje všechno, co počínaje první bílou mezerou (whitespace) v MIME hlavičce Content-Type obdrží od klienta. Za existence tohoto jevu nebude CERN httpd podporovat uploading souborů.

Uploading více souborů

Více souborů může být uploadování za použití různých názvů name pro souborové pole input.

Je také možné uploadovat více souborů současně a nechat informace automaticky zorganizovat v polích. V takovém případě je třeba použít stejnou syntaxi v HTML formuláři jako pro vícenásobné výběry a zaškrtávací políčka (checkboxy).

Poznámka: Podpora pro upload více souborů byla přidána ve verzi 3.0.10.

Příklad 20-3. Uploading více souborů

<form action="file-upload.php" method="post" enctype="multipart/form-data"> Send these files:<br> <input name="userfile[]" type="file"><br> <input name="userfile[]" type="file"><br> <input type="submit" value="Send files"> </form>

Pokud je výše uvedený formulář odeslán, pole $HTTP_POST_FILES['userfile'], $HTTP_POST_FILES['userfile']['name'], a $HTTP_POST_FILES['userfile']['size'] budou inicializována (jak $_FILES v PHP 4.1.0 a pozdějším, tak $HTTP_POST_VARS v PHP 3. Pokud je nastavení register_globals aktivní globální proměnné pro uploadované soubory jsou také inicializovány). Každé z nich bude číselně indexované pole odpovídajících hodnot pro odeslané soubory.

Kupříkladu předpokládejme, že se posílají soubory s názvy /home/test/review.html a /home/test/xwp.out. V tom případě by $HTTP_POST_FILES['userfile']['name'][0] obsahovalo hodnotu review.html a $HTTP_POST_FILES['userfile']['name'][1] hodnotu xwp.out. Podobně $HTTP_POST_FILES['userfile']['size'][0] by obsahovalo velikost review.html atd.

$HTTP_POST_FILES['userfile']['name'][0], $HTTP_POST_FILES['userfile']['tmp_name'][0], $HTTP_POST_FILES['userfile']['size'][0] a $HTTP_POST_FILES['userfile']['type'][0] budou rovněž nastaveny.

Podpora metody PUT

PHP poskytuje podporu pro HTTP PUT metodu používanou klienty jako Netscape Composer nebo W3C Amaya. Požadavky s metodou PUT jsou mnohem jednodušší než upload souborů a vypadají přibližně takto:

PUT /path/filename.html HTTP/1.1

Toto by normálně znamenalo, že by chtěl klient uložit obsah, který následuje za názvem /path/filename.html, do svého webového stromu. To samozřejmě není dobrý nápad, aby Apache nebo PHP automaticky nechal kohokoli přepsat jakékoli soubory ve stromě. Takže, pro zpracování takového požadavku je třeba nejdřív řici vašemu WWW serveru, že chcete požadavek zpracovávat konkrétním PHP skriptem. U serveru Apache se to provede direktivou Script. Může být umístěna kdekoli v konfiguračním souboru Apache. Častými místy jsou bloky <Directory> a <Virtualhost>. Použije se k tomu řádek podobný tomuto:

Skript PUT /put.php

Toto řekne serveru Apache, aby všechny PUT požadavky na nějaký URI vyhovující kontextu posílal skriptu put.php. To pochopitelně předpokládá, že máte povoleno PHP pro příponu .php a PHP je aktivní.

V souboru put.php byste potom mohli napsat něco jako:

<?php copy($PHP_UPLOADED_FILE_NAME,$DOCUMENT_ROOT.$REQUEST_URI); ?>

Toto by mělo zkopírovat soubor na místo požadované vzdáleným klientem. Pravděpodobně byste chtěli provést nějaká ověření a/nebo autentizace uživatele před provedením tohoto zkopírování. Jediným použitelným trikem je, že PHP uloží přenesený soubor do dočasného adresáře podobně, jako při použití metody POST. Až skript skončí, dočasný soubor bude odstraněn. Takže váš PHP skipt pro zpracování PUT požadavků musí soubor zkopírovat jinam. Název souboru v dočasném umístění je uložen v proměnné $PHP_PUT_FILENAME a požadovaný název cílového souboru v proměnné $REQUEST_URI (může se lišit u serverů jiných než Apache). Toto cílové jméno je to jediné, co klient specifikoval. Nemusíte ho poslechnout. Mohli byste, například, kopírovat všechny uploadované soubory do speciálního uploadového adresáře.

Kapitola 21. Použití vzdálených souborů

Pokud při konfiguraci PHP aktivujete podporu "URL fopen wrapper" (standardně je zapnutá, ledaže pro configure explicitně zadáte --disable-url-fopen-wrapper příznak (verze do 4.0.3), nebo (u novějších verzí) nastavíte allow_url_fopen v php.ini na off), můžete ve voláních většiny funkcí, které očekávají jako argument název souboru (včetně require() a include()) uvést HTTP nebo FTP URL.

Poznámka: Na Windows nelze používat vzdálené soubory v include() a require() výrazech.

Můžete například otevřít soubor na vzdáleném web serveru, vyseparovat z výstupu data, která potřebujete, a tato data potom použít v dotazu na databázi, nebo je prostě začlenit do výstupu stylem odpovídajícím zbytku vaší web site.

Příklad 21-1. Získání názvu vzdálené stránky

<?php $file = fopen ("http://www.php.net/", "r"); if (!$file) { echo "<p>Nelze otevřít vzdálený soubor.\n"; exit; } while (!feof ($file)) { $line = fgets ($file, 1024); /* Toto bude fungovat pouze pokud jsou tagy a název na jedné řádce */ if (eregi ("<title>(.*)</title>", $line, $out)) { $title = $out[1]; break; } } fclose($file); ?>

Pokud se připojíte jako uživatel s dostatečnými právy, a daný soubor už neexistuje, můžete data také ukládat po FTP. Pokud se chcete připojit jako jiný uživatel než 'anonymous', musíte v URL udat uživatelské jméno (a pravděpodobně i heslo), např. 'ftp://uzivatel:heslo@ftp.example.com/path/to/file'. (Pro přístup k souborům přes HTTP, které vyžadují Basic authentication, můžete použít stejnou syntaxi.)

Příklad 21-2. Uložení dat na vzdáleném serveru

<?php $file = fopen ("ftp://ftp.php.net/incoming/outputfile", "w"); if (!$file) { echo "<p>Nelze otevřít vzdálený soubor pro zápis.\n"; exit; } /* Zapíšeme data. */ fputs ($file, "$HTTP_USER_AGENT\n"); fclose ($file); ?>

Poznámka: Z výše uvedeného příkladu by vás mohlo napadnout využít tuto techniku k zápisu do vzdáleného logu, ale jak už bylo zmíněno výše, pomocí URL fopen() wrapperu můžete zapisovat pouze do nového souboru. Pokud máte zájem o distribuované logování, podívejte se na syslog().

Kapitola 22. Obsluha spojení

Poznámka: Následující text platí pro verzi 3.0.7 a vyšší.

Stav spojení se v PHP interně sleduje. Jsou tři možné stavy:

0 - NORMAL (normální)
1 - ABORTED (zrušeno)
2 - TIMEOUT (vypršel časový limit)

Při normálním běhu PHP skriptu je aktivní stav NORMAL. Pokud se klient odpojí, nastaví se příznak ABORTED. K odpojení vzdáleného klienta typicky dochází, když uživatel zmáčkne tlačítko STOP. Pokud se dosáhne časového limitu (viz set_time_limit()), nastaví se stavový příznak TIMEOUT.

Můžete se rozhodnout jestli chcete, aby odpojení klienta způsobilo předčasné ukončení vašeho skriptu. Někdy je užitečné nechat skripty doběhnout do konce, přestože není vzdáleného browseru, který by přijímal výstup. Výchozí chování je nicméně takové, že při odpojení vzdáleného klienta dojde k ukončení běhu skriptu. Toto chování se dá změnit skrze konfigurační direktivu ignore_user_abort v php3.ini, odpovídající direktivu php3_ignore_user_abort v .conf souboru Apache, či funkci ignore_user_abort(). Pokud nedáte PHP pokyn ignorovat odpojení uživatele a ten se odpojí, váš skript se ukončí. Výjimkou je, pokud máte pomocí register_shutdown_function() zaregistrovanou funkci pro provedení při ukončení skriptu. V tom případě, pokud vzdálený uživatel zmáčkne tlačítko STOP, při dalším pokusu tohoto skriptu odeslat výstup PHP detekuje, že spojení bylo zrušeno, a zavolá se funkce zaregistrovaná pro provedení při ukončení skriptu. Tato funkce se zavolá také na konci běhu skriptu končícím normálně, takže pokud chcete po zrušeném spojení udělat něco jiného, můžete použít connection_aborted(). Tato funkce vrátí TRUE, pokud bylo spojení zrušeno.

Váš skript může také ukončit vestavěný čítač času. Výchozí časový limit je 30 sekund. To se dá změnit max_execution_time direktivou v phpš.ini nebo odpovídající php3_max_execution_time direktivou v .conf souboru Apahe, či voláním funkce set_time_limit(). Když čítač času doběhne, skript se ukončí, a jako ve výše uvedeném případě uživatelského odpojení, pokud je zaregistrovaná funkce pro provedení při ukončení skriptu, tato se zavolá. Uvnitř této funkce můžte zkontrolovat, jestli její zavolání způsobilo doběhnutí čítače času zavoláním funkce connection_timeout(). Tato funkce vrátí TRUE, pokud volání funkce registrované pro provedení při ukončení skriptu způsobilo doběhnutí čítače času.

Skutečností hodnou povšimnutí je, že stavy ABORTED a TIMEOUT mohou být aktivní současně. Možné je to v případě, že nařídíte PHP ignorovat odpojení uživatee. PHP i tak bude vědět, že uživatel přerušil spojení, ale skript poběží dál. Pokud potom dosáhne časového limitu, bude ukončen, a zavolá se vaše funkce pro provedení při ukončení skriptu, pokud existuje. V tomto okamžiku zjistíte, že jak connection_timeout(), tak connection_aborted() vracejí TRUE. Oba stavy můžete zkontrolovat jediným voláním funkce connection_status(). Tato funkce vrací bitové pole aktivních stavů. Takže například, pokud jsou aktivní oba tyto stavy, vrátí 3.

Kapitola 23. Persistentní databázová spojení

Trvalá spojení jsou SQL spojení, která se nezavírají na konci průběhu skriptu. Při požadavku na trvalé spojení PHP nejdříve zkontroluje, jestli už neexistuje identické spojení (které zůstalo otevřeno z dřívějška) - a pokud existuje, použije ho. Pokud neexistuje, PHP ho otevře. "Identické" spojení je spojení, které bylo otevřeno se stejným serverem, uživatelským jménem a heslem (pokud je zadáte).

Poznámka: Existují i další rozšíření, která vytváří trvalá spojení, například Rozšíření IMAP.

Lidé, kteří nejsou důkladně obeznámeni se způsobem, jakým web servery fungují a distribuují zátěž, mohou pokládat trvalá spojení za něco čím nejsou. Zvláště neumožňují otvírání "uživatelských sessions" na stejném SQL spojení, neumožňují efektivní tvorbu transakcí, a neumožňují spoustu dalších věcí. Dokonce, aby o tom bylo opravdu a důkladně jasno, vám trvalá spojení nedají žádnou funkcionalitu, která by nebyla možná s jejich netrvalými protějšky.

Proč?

To je dáno způsobem, jakým fungují webové servery. Jsou tři způsoby, jakými váš web server může využít PHP ke generování webových stránek.

První metodou je použít PHP jako CGI "obal". V tomto režimu se vytváří a ničí jedna instance PHP interpretru pro každý požadavek (na PHP strnánku) na vašem web serveru. Protože je zničena po obsloužení požadavku, všechny zdroje, které získá (jako třeba spojení s databázovým serverem) jsou při jejím zničení zavřeny. V tomto případě pokusem o použití trvalých spojení nic nezískáte - prostě nevydrží.

Druhou, a nejpopulárnější, metodou, je provozovat PHP jako modul v multiprocesním web serveru, což je množina, která v současnosti obsahuje pouze Apache. Multiprocesní web server má typicky jeden proces (rodiče), který řídí skupinu procesů (svých dětí), které dělají vlastní práci - servírují stránky. Každý požadavek, který přijde od klienta, je obsloužen jedním z dětí, které právě neobsluhuje jiného klienta. To znamená, že když stejný klient vznese další požadavek na stejný server, tento může být obsloužen jiným dětským procesem než ten první. Trvalá spojení zajišťují, aby se každý dětský proces musel na váš SQL server přihlásit pouze při prvním odeslání stránky, která takové spojení využívá. Když spojení s SQL serverem vyžaduje další stránka, může použít spojení, které toto dítě otevřelo už dříve.

Poslední metodou je použít PHP jako plug-in v multivláknovém web serveru. Aktuálně PHP 4 má tuto podporu pro ISAPI, WSAPI a NSAPI (na Windows), což umožnuje používat PHP jako plug-in v multivláknových serverech jako Netscape FastTrack (iPlanet), Microsoft Internet Information Server (IIS), a O'Reilly's WebSite Pro. Chování je stejné jako u multiprocesním modelu popsaném dříve. Podpora pro SAPI není dostupná v PHP 3.

Pokud trvalá spojení neposkytují žádnou přidanou funkcionalitu, k čemu jsou dobrá?

Odpověď na tuto otázku je velmi jednoduchá - efektivita. Trvalá spojení jsou dobrá, pokud má tvorba spojení s vaším SQL serverem vysokou režii. Reálná výše této režie záleží na mnoha faktorech. Například jaký je to typ databáze, jestli sídlí na stejném počítači jako váš webserver, jak zatížený je stroj, na kterém váš SQL server běží a tak dále. Pointa je, že pokud je spojovací režie vysoká, trvalá spojení vám znatelně pomohou. Umožní dětskému procesu připojit se pouze jednou za celý jeho životní cyklus místo každého zpracování stránky, která vyžaduje spojení s SQL serverem. To znamená, že každé dítě, které otevřelo trvalé spojení, bude mít otevřené vlastní trvalé spojení se serverem. Pokud například máte 20 dětských procesů, které spustily skript, který otevřel trvalé spojení s vaším SQL serverem, máte 20 nezávislých spojení s SQL serverem, po jednom z každého dítěte.

Všimněte si nicméně, že to může mít nevýhody, pokud používate databázi s omezeným počtem připojení, který trvalá spojení dětí překročí. Pokud má vaše databáze limit 16 současných připojení, a v rušném okamžiku se pokusí připojit 17 dětských procesů, jednomu se to nepodaří. Pokud máte ve svých skriptech chyby, které brání zavírání spojení (např. nekonečné smyčky), databáze s pouhými 32 spojeními bude brzy zaplavena. Vyhledejte si v dokumentaci vaší databáze informace o obsluze opuštěných nebo nečinných spojení.

Varování

Zde je několik dodatečných námitek, které se usadily v mysli během používání trvalých spojení. Jedna z nich je, když používáte zamknuté tabulky při trvalém spojení a skript z jakéhokoli důvodu nemůže uvolnit zámek, pak následující skript, který používá stejné spojení, bude nejspíše na trvalo zablokován a možná bude nutné, abyste pokaždé restartovali http server nebo databázový server. Dále pak v případě použití transakcí se transakční blok přenese i do dalšího skriptu používajícího stejné spojení, pokud jeho vykonání končí dříve než transakční blok. V každém případě můžete použít register_shutdown_function() k registraci a jednoduchému vyčištění funkce pro odemknutí tabulek nebo zrušení běžící transakce (roll back). Nejlépe se problému vyvarujete úplně nepoužíváním trvalých spojení ve skriptech, ve kterých se zamykají tabulky nebo používají transakce (můžete je stále používat na mnohých dalších místech).

Důležitý souhrn. Trvalá spojení byla navržena tak, aby odpovídala jedna k jedné normálním spojením. To znamená, že byste vždy měli být schopni nahradit trvalá spojení netrvalými beze změny fungování vašeho skriptu. Může to (a pravděpodobně bude) mít vliv na efektivitu tohoto skriptu, ale ne jeho chování!

Dále také: fbsql_pconnect(), ibase_pconnect(), ifx_pconnect(), imap_popen(), ingres_pconnect(), msql_pconnect(), mssql_pconnect(), mysql_pconnect(), OCIPLogon(), odbc_pconnect(), Ora_pLogon(), pfsockopen(), pg_pconnect() a sybase_pconnect().

Kapitola 24. Bezpečný režim

Bezpečný režim PHP je pokus o řešení bezpečnosti sdílených serverů. Je architekturálně nekorektní pokoušet se řešit tento problém na úrovni PHP, ale protože řešení na úrovni webovského serveru a operačního systému nejsou příliš realistická, mnoho lidí, zvlaště ISP, používá nyní bezpečný režim.

Konfigurační direktivy, které ovládají bezpečný režim:

safe_mode = Off open_basedir = safe_mode_exec_dir = safe_mode_allowed_env_vars = PHP_ safe_mode_protected_env_vars = LD_LIBRARY_PATH disable_functions =

Pokud je safe_mode zapnutý, PHP kontroluje, je-li vlastník běžícího skriptu vlastníkem souboru, s nímž se má manipulovat. Například:

-rw-rw-r-- 1 rasmus rasmus 33 Jul 1 19:20 script.php -rw-r--r-- 1 root root 1116 May 26 18:01 /etc/passwd
Spuštění skriptu script.php

<?php readfile('/etc/passwd'); ?>
bude mít v bezpečném režimu za výsledek tuto chybu:

Warning: SAFE MODE Restriction in effect. The script whose uid is 500 is not allowed to access /etc/passwd owned by uid 0 in /docroot/script.php on line 2

Pokud namísto safe_mode nastavíte adresář open_basedir, potom všechny operace se soubory budou omezeny pod specifikovaný adresář. Například (příklad Apache httpd.conf):

<Directory /docroot> php_admin_value open_basedir /docroot </Directory>
Když spustíte tentýž soubor script.php s timto nastavením open_basedir, dostanete tento výsledek:

Warning: open_basedir restriction in effect. File is in wrong directory in /docroot/script.php on line 2

Můžete také vypnout jednotlivé funkce. Pokud přidáme toto do souboru php.ini:

disable_functions readfile,system
získáme takovýto výstup:

Warning: readfile() has been disabled for security reasons in /docroot/script.php on line 2

Funkce omezené/deaktivované v bezpečném režimu

Toto je pravděpodobně neúplný a možná nesprávný přehled funkcí omezených v bezpečném režimu.

Tabulka 24-1. Funkce omezené v bezpečném režimu

Funkce	Omezení
dbmopen()	Kontroluje, zda soubory/adresáře, se kterými pracujete, mají stejné UID jako spuštěný skript.
dbase_open()	Kontroluje, zda soubory/adresáře, se kterými pracujete, mají stejné UID jako spuštěný skript.
filepro()	Kontroluje, zda soubory/adresáře, se kterými pracujete, mají stejné UID jako spuštěný skript.
filepro_rowcount()	Kontroluje, zda soubory/adresáře, se kterými pracujete, mají stejné UID jako spuštěný skript.
filepro_retrieve()	Kontroluje, zda soubory/adresáře, se kterými pracujete, mají stejné UID jako spuštěný skript.
*ifx_()**	sql_safe_mode restrictions, (!= safe mode)
*ingres_()**	sql_safe_mode restrictions, (!= safe mode)
*mysql_()**	sql_safe_mode restrictions, (!= safe mode)
pg_loimport()	Kontroluje, zda soubory/adresáře, se kterými pracujete, mají stejné UID jako spuštěný skript.
posix_mkfifo()	Kontroluje, zda adresář, ve kterém pracujete, má stejné UID jako spuštěný skript.
putenv()	Obeys the safe_mode_protected_env_vars and safe_mode_allowed_env_vars ini-directives. Viz také dokumentaci putenv()
move_uploaded_file()	Kontroluje, zda soubory/adresáře, se kterými pracujete, mají stejné UID jako spuštěný skript.
chdir()	Kontroluje, zda adresář, ve kterém pracujete, má stejné UID jako spuštěný skript.
dl()	Tyto funkce jsou v bezpečném režimu (safe-mode) deaktivovány.
backtick operátor	Tyto funkce jsou v bezpečném režimu (safe-mode) deaktivovány.
shell_exec() (funkční ekvivalent backticks)	Tyto funkce jsou v bezpečném režimu (safe-mode) deaktivovány.
exec()	Můžete spouštět programy pouze uvnitř adresáře safe_mode_exec_dir. Z praktických důvodů není momentálně možné mít v cestě k souboru s programem komponenty `..`.
system()	Můžete spouštět programy pouze uvnitř adresáře safe_mode_exec_dir. Z praktických důvodů není momentálně možné mít v cestě k souboru s programem komponenty `..`.
passthru()	Můžete spouštět programy pouze uvnitř adresáře safe_mode_exec_dir. Z praktických důvodů není momentálně možné mít v cestě k souboru s programem komponenty `..`.
popen()	Můžete spouštět programy pouze uvnitř adresáře safe_mode_exec_dir. Z praktických důvodů není momentálně možné mít v cestě k souboru s programem komponenty `..`.
mkdir()	Kontroluje, zda adresář, ve kterém pracujete, má stejné UID jako spuštěný skript.
rmdir()	Kontroluje, zda soubory/adresáře, se kterými pracujete, mají stejné UID jako spuštěný skript.
rename()	Kontroluje, zda soubory/adresáře, se kterými pracujete, mají stejné UID jako spuštěný skript. Kontroluje, zda adresář, ve kterém pracujete, má stejné UID jako spuštěný skript.
unlink()	Kontroluje, zda soubory/adresáře, se kterými pracujete, mají stejné UID jako spuštěný skript. Kontroluje, zda adresář, ve kterém pracujete, má stejné UID jako spuštěný skript.
copy()	Kontroluje, zda soubory/adresáře, se kterými pracujete, mají stejné UID jako spuštěný skript. Kontroluje, zda adresář, ve kterém pracujete, má stejné UID jako spuštěný skript. (pro `source` a `target`)
chgrp()	Kontroluje, zda soubory/adresáře, se kterými pracujete, mají stejné UID jako spuštěný skript.
chown()	Kontroluje, zda soubory/adresáře, se kterými pracujete, mají stejné UID jako spuštěný skript.
chmod()	Kontroluje, zda soubory/adresáře, se kterými pracujete, mají stejné UID jako spuštěný skript. Navíc nemůžete nastavovat SUID, SGID a sticky bit
touch()	Kontroluje, zda soubory/adresáře, se kterými pracujete, mají stejné UID jako spuštěný skript. Kontroluje, zda adresář, ve kterém pracujete, má stejné UID jako spuštěný skript.
symlink()	Kontroluje, zda soubory/adresáře, se kterými pracujete, mají stejné UID jako spuštěný skript. Kontroluje, zda adresář, ve kterém pracujete, má stejné UID jako spuštěný skript. (pozn.: testován je pouze cíl)
link()	Kontroluje, zda soubory/adresáře, se kterými pracujete, mají stejné UID jako spuštěný skript. Kontroluje, zda adresář, ve kterém pracujete, má stejné UID jako spuštěný skript. (pozn.: testován je pouze cíl)
getallheaders()	V bezpečném režimu nebudou hlavičky začínající 'authorization' (bez ohledu na velikost písmen) vraceny. Varování: toto nefunguje s aol-server implementací getallheaders()!
Jakékoli funkce které používají `php4/main/fopen_wrappers.c`	??

Kapitola 25. Using PHP from the command line

Since version 4.3, PHP supports a new SAPI type (Server Application Programming Interface) named CLI which means Command Line Interface. As the name implies, this SAPI type main focus is on developing shell (or desktop as well) applications with PHP. There are quite some differences between the CLI SAPI and other SAPIs which are further explained throughout this chapter.

The CLI SAPI was released for the first time with PHP 4.2.0, but was still experimental back then and had to be explicitely enabled with --enable-cli when running ./configure. Since PHP 4.3.0 the CLI SAPI is no longer experimental and is therefore always built and installed as the php (called php.exe on Windows) binary.

Remarkable differences of the CLI SAPI compared to other SAPIs:

Unlikely the CGI SAPI, no headers are written to the output.

Though the CGI SAPI provies a way to suppress HTTP headers, there's not equivalent switch to enable them in the CLI SAPI.

The are certain php.ini directives which are overriden by the CLI SAPI because the do not make sense in shell environments:

Tabulka 25-1. Overriden php.ini directives

Directive	`CLI SAPI` default value	Comment
html_errors	`FALSE`	It can be quite hard to read the error message in your shell when it's cluttered with all those meaningless `HTML` tags, therefore this directive defaults to `FALSE`.
implicit_flush	`TRUE`	It is desired that any output coming from print(), echo() and friends is immidiately written to the output and not cached in any buffer. You still can use output buffering if you want to defer or manipulate standard output.
max_execution_time	0 (unlimited)	Due to endless possibilities of using `PHP` in shell environments, the maximum execution time has been set to unlimited. Whereas applications written for the web are executed within splits of a seconds, shell application tend to have a much longer execution time.
register_argc_argv	`TRUE`	The global `PHP` variables `$argc` (number of arguments passed to the application) and `$argv` (array of the actual arguments) are always registered and filled in with the appropriate values when using the `CLI SAPI`.

Poznámka: These directives cannot be initialzied with another value from the configuration file php.ini or a custom one (if specified). This is a limitation because those default values are applied after all configuration files have been parsed. However, their value can be changed during runtime (which does not make sense for all of those directives, e.g. register_argc_argv).

To ease working in the shell environment, the following constants are defined:

Tabulka 25-2. CLI specific Constants

Constant Description

STDIN

An already opened stream to stdin. This saves opening it with

$stdin = fopen('php://stdin', 'r');

STDOUT

An already opened stream to stdout. This saves opening it with

$stdout = fopen('php://stdout', 'w');

STDERR

An already opened stream to stdout. This saves opening it with

$stderr = fopen('php://stderr', 'w');

Given the above, you don't need to open e.g. a stream for stderr yourself but simply use the constant instead of the stream resource:

php -r 'fwrite(STDERR, "stderr\n");'
You do not need to explicitly close these streams, this is automatically done by PHP.

The CLI SAPI does not change the current directory to the directory of the executed script !
Example showing the difference to the CGI SAPI:
<?php /* Our simple test application */ echo getcwd(), "\n"; ?>
When using the CGI version, the output is
$ pwd /tmp $ php-cgi -f another_directory/test.php /tmp/another_directory
This clearly shows that PHP changes its current directory to the one of the executed script.
Using the CLI SAPI yields:
$ pwd /tmp $ php -f another_directory/test.php /tmp
This allows greater flexibility when writing shell tools in PHP.
Poznámka: The CGI SAPI supports the CLI SAPI behaviour by means of the -C switch when ran from the command line.

The list of command line options provided by the PHP binary can be queried anytime by running PHP with the -h switch:

Usage: php [options] [-f] <file> [args...] php [options] -r <code> [args...] php [options] [-- args...] -s Display colour syntax highlighted source. -w Display source with stripped comments and whitespace. -f <file> Parse <file>. -v Version number -c <path>|<file> Look for php.ini file in this directory -a Run interactively -d foo[=bar] Define INI entry foo with value 'bar' -e Generate extended information for debugger/profiler -z <file> Load Zend extension <file>. -l Syntax check only (lint) -m Show compiled in modules -i PHP information -r <code> Run PHP <code> without using script tags <?..?> -h This help args... Arguments passed to script. Use -- args when first argument starts with - or script is read from stdin

The CLI SAPI has three different ways of getting the PHP code you want to execute:

Telling PHP to execute a certain file.
php my_script.php php -f my_script.php
Both ways (using the -f switch or not) execute the given file my_script.php. You can choose any file to execute, your PHP scripts do not have to end with the .php extension but can give them any name or extension you want them to have.
Pass the PHP code to execute directly on the command line.
php -r 'print_r(get_defined_constants());'
Special care has to be taken in regards of shell variable substitution and quoting usage.
Poznámka: Read the example carefully, thera are no beginning or ending tags! The -r switch simply does not need them. Using them will lead to a parser error.
Provide the PHP code to execute via standard input (stdin).
This gives the powerful ability to dynamically create PHP code and feed it to the binary, as shown in this (fictional) example:
$ some_application | some_filter | php | sort -u >final_output.txt

You cannot combine any of the three ways to execute code.

Like every shell application, the PHP binary accepts a number of arguments but also your PHP script can receive them. The number of arguments which can be passed to your script is not limited by PHP (the shell has a certain size limit in numbers of characters which can be passed; usually you won't hit this limit). The arguments passed to your script are available in the global array $argv. The zero index always contains the script name (which is - in case the PHP code is coming from either standard input or from the command line switch -r). The second registered global variable is $argc which contains the number of elements in the $argv array (not the number of arguments passed to the script).

As long as the arguments you want to pass to your script do not start with the - character, there's nothing special to watch out for. Passing an argument to your script which starts with a - will cause trouble because PHP itself thinks it has to handle it. To prevent this use the argument list separator --. After the argument has been parsed by PHP, every argument following it is passed untoched/unparsed to your script.

# This will not execute the given code but will show the PHP usage
$ php -r 'var_dump($argv);' -h
Usage: php [options] [-f] <file> [args...]
[...]

# This will pass the '-h' argument to your script and prevent PHP from showing it's usage
$ php -r 'var_dump($argv);' -- -h
array(2) {
  [0]=>
  string(1) "-"
  [1]=>
  string(2) "-h"
}

However, there's another way of using PHP for shell scripting. You can write a script where the first line starts with #!/usr/bin/php and then following the normal PHP code included within the PHP starting and end tags and set the execution attributes of the file appropriately. This way it can be executed like a normal shell or perl script:

#!/usr/bin/php <?php var_dump($argv); ?>
Assuming this file is named test in the current directory, we can now do the following:

$ chmod 755 test $ ./test -h -- foo array(4) { [0]=> string(6) "./test" [1]=> string(2) "-h" [2]=> string(2) "--" [3]=> string(3) "foo" }
As you see no care has to be taken when passing parameters to your script which start with -.

Tabulka 25-3. Command line options

Option Description

-s

Display colour syntax highlighted source.

This option uses the internal mechanism to parse the file and produces a HTML highlighted version of it and writes it to standard output. Note that all it does it to generate a block of <code> [...] </code> HTML tags, no HTML headers.

Poznámka: This option does not work together with the -r option.

-w

Display source with stripped comments and whitespace.

Poznámka: This option does not work together with the -r option.

-f

Parses and executed the given filename to the -f option. This switch is optional and can be left out. Only providing the filename to execute is sufficient.

-v

Writes the PHP, PHP SAPI, and Zend version to standard output, e.g.

$ php -v PHP 4.3.0-dev (cli), Copyright (c) 1997-2002 The PHP Group Zend Engine v1.2.1, Copyright (c) 1998-2002 Zend Technologies

-c

With this option one can either specify a directory where to look for php.ini or you can specify a custom INI file directly (which does not need to be named php.ini), e.g.:

$ php -c /custom/directory/ my_script.php $ php -c /custom/directory/custom-file.ini my_script.php

-a

Runs PHP interactively.

-d

This option allows to set a custom value for any of the configuration directives allowed in php.ini. The syntax is:

-d configuration_directive[=value]

Examples:

# Ommiting the value part will set the given configuration directive to "1" $ php -d max_execution_time -r '$foo = ini_get("max_execution_time"); var_dump($foo);' string(1) "1" # Passing an empty value part will set the configuration directive to "" php -d max_execution_time= -r '$foo = ini_get("max_execution_time"); var_dump($foo);' string(0) "" # The configuration directive will be set to anything passed after the '=' character $ php -d max_execution_time=20 -r '$foo = ini_get("max_execution_time"); var_dump($foo);' string(2) "20" $ php -d max_execution_time=doesntmakesense -r '$foo = ini_get("max_execution_time"); var_dump($foo);' string(15) "doesntmakesense"

-e

Generate extended information for debugger/profiler.

-z

Load Zend extension. If only a filename is given, PHP tries to load this extension from the current default library path on your system (usually specified /etc/ld.so.conf on Linux systems). Passing a filename with an absolute path information will not use the systems library search path. A relative filename with a directory information will tell PHP only to try to load the extension relative to the current directory.

-l

This option provides a convenient way to only perform a syntax check on the given PHP code. On succes, the text No syntax errors detected in <filename> is written to standard output and the shell return code is 0. On failure, the text Errors parsing <filename> in addition to the internal parser error message is written to standard output and the shell return code is set to 255.

This option won't find fatal errors (like undefined functions). Use -f if you would like to test for fatal errors too.

Poznámka: This option does not work together with the -r option.

-m

Using this option, PHP prints out the built in (and loaded) PHP and Zend modules:

$ php -m [PHP Modules] xml tokenizer standard session posix pcre overload mysql mbstring ctype [Zend Modules]

-i This command line option calls phpinfo(), and prints out the results. If PHP is not working well, it is advisable to make a php -i and see if any error messages are printed out before or in place of the information tables. Beware that the output is in HTML and therefore quite huge.

-r

This option allows execution of PHP right from within the command line. The PHP start and end tags (<?php and ?>) are not needed and will cause a parser errors.

Poznámka: Care has to be taken when using this form of PHP to not collide with command line variable substitution done by the shell.
Example showing a parser error
$ php -r "$foo = get_defined_constants();"
Command line code(1) : Parse error - parse error, unexpected '='
The problem here is that the sh/bash performs variable substritution even when using double quotes ". Since the variable $foo is unlikely to be defined, it expands to nothing which results in being the code passed to PHP for executin in fact reads:
$ php -r " = get_defined_constants();"
The correct way would be to use single quotes '. variables in strings quoted with single quotes are not expanded by sh/bash.
$ php -r '$foo = get_defined_constants(); var_dump($foo);'
array(370) {
  ["E_ERROR"]=>
  int(1)
  ["E_WARNING"]=>
  int(2)
  ["E_PARSE"]=>
  int(4)
  ["E_NOTICE"]=>
  int(8)
  ["E_CORE_ERROR"]=>
  [...]
If you are using a shell different from sh/bash, you might experience further issues. Feel free to open a bug report or send a mail to phpdoc@lists.php.net. One still can easily run intro troubles when trying to get shell variables into the code or using backslashes for escaping. You've been warned.

-h With this option, you can get information about the actual list of command line options and some one line descriptions about what they do.

The PHP executable can be used to run PHP scripts absolutely independent from the web server. If you are on a Unix system, you should add a special first line to your PHP script, and make it executable, so the system will know, what program should run the script. On a Windows platform you can associate php.exe with the double click option of the .php files, or you can make a batch file to run the script through PHP. The first line added to the script to work on Unix won't hurt on Windows, so you can write cross platform programs this way. A simple example of writing a command line PHP program can be found below.

Příklad 25-1. Script intended to be run from command line (script.php)

#!/usr/bin/php
<?php

if ($argc != 2 || in_array($argv[1], array('--help', '-help', '-h', '-?'))) {
?>

This is a command line PHP script with one option.

  Usage:
  <?php echo $argv[0]; ?> <option>

  <option> can be some word you would like
  to print out. With the --help, -help, -h,
  or -? options, you can get this help.

<?php
} else {
    echo $argv[1];
}
?>

In the script above, we used the special first line to indicate, that this file should be run by PHP. We work with a CLI version here, so there will be no HTTP header printouts. There are two variables you can use while writing command line applications with PHP: $argc and $argv. The first is the number of arguments plus one (the name of the script running). The second is an array containing the arguments, starting with the script name as number zero ($argv[0]).

In the program above we checked if there are less or more than one arguments. Also if the argument was --help, -help, -h or -?, we printed out the help message, printing the script name dynamically. If we received some other argument we echoed that out.

If you would like to run the above script on Unix, you need to make it executable, and simply call it as script.php echothis or script.php -h. On Windows, you can make a batch file for this task:

Příklad 25-2. Batch file to run a command line PHP script (script.bat)

@c:\php\php.exe script.php %1 %2 %3 %4

Assuming, you named the above program as script.php, and you have your php.exe in c:\php\php.exe this batch file will run it for you with your added options: script.bat echothis or script.bat -h.

See also the Readline extension documentation for more functions you can use to enhance your command line applications in PHP.

IV. Reference funkcí

Obsah
I. Funkce specifické pro Apache
II. Funkce pro práci s poli
III. Aspell funkce
IV. BCMath funkce pro výpočty s libovolnou přesností
V. Kompresní funkce bzip2
VI. Kalendářové funkce
VII. CCVS API Funkce
VIII. Funkce na podporu COM ve Windows
IX. Funkce pro práci s třídami/objekty
X. ClibPDF functions
XI. Crack functions
XII. Funkce pro práci s CURL, Client URL Library
XIII. Cybercash platební funkce
XIV. Crédit Mutuel CyberMUT functions
XV. Cyrus IMAP administration functions
XVI. Character type functions
XVII. Database (dbm-style) abstraction layer functions
XVIII. Date and Time functions
XIX. dBase functions
XX. DBM Funkce
XXI. dbx functions
XXII. DB++ Functions
XXIII. Direct IO functions
XXIV. Adresářové funkce
XXV. DOM XML funkce
XXVI. .NET functions
XXVII. Error Handling and Logging Functions
XXVIII. FrontBase Functions
XXIX. filePro funkce
XXX. Filesystémové funkce
XXXI. Forms Data Format functions
XXXII. FriBiDi functions
XXXIII. FTP functions
XXXIV. Funkce pro práci s funkcemi
XXXV. GNU Gettext
XXXVI. GMP functions
XXXVII. HTTP funkce
XXXVIII. Hyperwave functions
XXXIX. Hyperwave API functions
XL. ICAP funkce
XLI. iconv functions
XLII. Image functions
XLIII. IMAP, POP3 and NNTP functions
XLIV. Informix functions
XLV. InterBase functions
XLVI. Ingres II functions
XLVII. IRC Gateway Functions
XLVIII. Java
XLIX. LDAP functions
L. Mailové funkce
LI. mailparse functions
LII. Mathematical Functions
LIII. Multi-Byte String Functions
LIV. MCAL functions
LV. Mcrypt Encryption Functions
LVI. Mhash funkce
LVII. Mimetype Functions
LVIII. Microsoft SQL Server functions
LIX. Ming functions for Flash
LX. Smíšené funkce
LXI. mnoGoSearch Functions
LXII. mSQL functions
LXIII. MySQL Funkce
LXIV. Mohawk Software session handler functions
LXV. muscat functions
LXVI. Síťové funkce
LXVII. Ncurses terminal screen control functions
LXVIII. Lotus Notes functions
LXIX. Unified ODBC functions
LXX. Oracle 8 functions
LXXI. OpenSSL funkce
LXXII. Oracle functions
LXXIII. Ovrimos SQL functions
LXXIV. Output Control funkce
LXXV. Object property and method call overloading
LXXVI. PDF funkce
LXXVII. Funkce pro práci s Verisign Payflow Pro
LXXVIII. PHP volby & informace
LXXIX. POSIX functions
LXXX. PostgreSQL functions
LXXXI. Process Control Functions
LXXXII. Funkce Spouštění Programů
LXXXIII. Printer functions
LXXXIV. Pspell Functions
LXXXV. GNU Readline
LXXXVI. GNU Recode funkce
LXXXVII. Regular Expression Functions (Perl-Compatible)
LXXXVIII. qtdom functions
LXXXIX. Regular Expression Functions (POSIX Extended)
XC. Funkce pro práci se semafory a sdílenou pamětí
XCI. SESAM database functions
XCII. Session handling functions
XCIII. Funkce pro práci se sdílenou pamětí
XCIV. Shockwave Flash functions
XCV. SNMP functions
XCVI. Socket functions
XCVII. Funkce pro práci s řetězci
XCVIII. Sybase functions
XCIX. Tokenizer functions
C. URL Functions
CI. Variable Functions
CII. vpopmail functions
CIII. W32api functions
CIV. WDDX funkce
CV. XML parser functions
CVI. XML-RPC functions
CVII. XSLT funkce
CVIII. YAZ functions
CIX. Funkce pro práci s YP/NIS
CX. Zip File Functions (Read Only Access)
CXI. Zlib Compression Functions

I. Funkce specifické pro Apache

Obsah
apache_child_terminate -- Terminate apache process after this request
apache_lookup_uri -- Provádí částečný požadavek na zadanou URI a vrací všechno info o ní
apache_note -- Získává a nastavuje poznámky požadavku u Apache.
apache_request_headers -- Fetch all HTTP request headers
apache_response_headers -- Fetch all HTTP response headers
apache_setenv -- Set an Apache subprocess_env variable
ascii2ebcdic -- Překládá řetězec z ASCII do EBCDIC
ebcdic2ascii -- Překládá řetězec z EBCDIC do ASCII
getallheaders -- Získává všechny hlavičky HTTP požadavku
virtual -- Provádí sub-požadavek Apache

apache_child_terminate

(PHP 4 >= 4.0.5)

apache_child_terminate -- Terminate apache process after this request

Description

bool apache_child_terminate ( void)

apache_child_terminate() will register the Apache process executing the current PHP request for termination once execution of PHP code it is completed. It may be used to terminate a process after a script with high memory consumption has been run as memory will usually only be freed internally but not given back to the operating system.

Poznámka: The availability of this feature is controlled by the php.ini directive apache.child_terminate, which is set to off by default.

This feature is also not available on multithreaded versions of apache like the win32 version.

apache_lookup_uri

(PHP 3>= 3.0.4, PHP 4 )

apache_lookup_uri -- Provádí částečný požadavek na zadanou URI a vrací všechno info o ní

Popis

class apache_lookup_uri ( string filename)

Tato funkce provádí částečný požadavek na URI. Jde jen tak daleko, aby získala všechny důležité informace o daném zdroji a vrací tyto informace ve třídě. Vlastnosti této třídy jsou:

status

the_request

status_line

method

content_type

handler

uri

filename

path_info

args

boundary

no_cache

no_local_copy

allowed

send_bodyct

bytes_sent

byterange

clength

unparsed_uri

mtime

request_time

Poznámka: apache_lookup_uri() pouze, pokud je PHP nainstalováno jako modul Apache.

apache_note

(PHP 3>= 3.0.2, PHP 4 )

apache_note -- Získává a nastavuje poznámky požadavku u Apache.

Popis

string apache_note ( string note_name [, string note_value])

apache_note() je funkce specifická pro Apache, která získává a nastavuje hodnoty v tabulce poznámek požadavku. Při volání s jedním argumentem vrací současnou hodnotu poznámky note_name. Při volání se dvěma argumenty nastavuje hodnotu poznámky note_name na note_value, a vrací předchozí hodnotu poznámky note_name.

apache_request_headers

(unknown)

apache_request_headers -- Fetch all HTTP request headers

Description

array apache_request_headers ( void)

apache_request_headers() returns an associative array of all the HTTP headers in the current request. This is only supported when PHP runs as an Apache module.

Poznámka: Prior to PHP 4.3.0, apache_request_headers() was called getallheaders(). After PHP 4.3.0, getallheaders() is an alias for apache_request_headers().

Příklad 1. apache_request_headers() Example

<?php $headers = apache_request_headers(); foreach ($headers as $header => $value) { echo "$header: $value <br />\n"; } ?>

Poznámka: You can also get at the value of the common CGI variables by reading them from the environment, which works whether or not you are using PHP as an Apache module. Use phpinfo() to see a list of all of the available environment variables.

apache_response_headers

(unknown)

apache_response_headers -- Fetch all HTTP response headers

Description

array apache_response_headers ( void)

Returns an array of all Apache response headers.

apache_setenv

(PHP 4 >= 4.2.0)

apache_setenv -- Set an Apache subprocess_env variable

Description

int apache_setenv ( string variable, string value [, bool walk_to_top])

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

ascii2ebcdic

(PHP 3>= 3.0.17)

ascii2ebcdic -- Překládá řetězec z ASCII do EBCDIC

Popis

int ascii2ebcdic ( string ascii_str)

ascii2ebcdic() je funkce specifická pro Apache dostupná pouze na operačních systémech založených na EBCDIC (OS/390, BS2000). Překládá (binárně bezpečně) řežězec v ASCII kódování ascii_str na jeho ekvivalentní EBCDIC reprezentaci, a vrací výsledek.

Viz také opačnou funkci ebcdic2ascii()

ebcdic2ascii

(PHP 3>= 3.0.17)

ebcdic2ascii -- Překládá řetězec z EBCDIC do ASCII

Popis

int ebcdic2ascii ( string ebcdic_str)

ebcdic2ascii() je funkce specifická pro Apache dostupná pouze na operačních systémech založených na EBCDIC (OS/390, BS2000). Překládá (binárně bezpečně) řežězec v kódování EBCDIC ascii_str na jeho ekvivalentní ASCII reprezentaci, a vrací výsledek.

Viz také opačnou funkci ascii2ebcdic()

getallheaders

(PHP 3, PHP 4 )

getallheaders -- Získává všechny hlavičky HTTP požadavku

Popis

array getallheaders ( void )

Tato funkce vrací asociativní pole všech HTTP hlaviček v současném požadavku.

Poznámka: Hodnotu běžných CGI proměnných můžete také získat tím, že je přečtete z prostředí, což funguje, ať používáte PHP jako modu Apache nebo ne. Pokud chcete vidět seznam všech systémových proměnných definovaných tímto způsobem, použijte phpinfo().

Příklad 1. getallheaders() Example

$headers = getallheaders(); while (list ($header, $value) = each ($headers)) { echo "$header: $value<br>\n"; }

Tento příklad zobrazí všechny hlavičky současného požadavku.

Poznámka: getallheaders() je v současnosti podporována jen když PHP běží jako modul Apache.

virtual

(PHP 3, PHP 4 )

virtual -- Provádí sub-požadavek Apache

Popis

int virtual ( string filename)

virtual() je funkce specifická pro Apache ekvivalentní s  v mod_include. Provádí sub-požadavek Apache. Je užitečná pro vkládání CGI skriptů nebo .shtml souborů, nebo čehokoliv jiného, co má Apache parsovat. CGI skripty musí generovat platné CGI hlavičky. To znamená, že musí přinejmenším generovat Content-type hlavičku. Pro PHP soubory musíte použít include() nebo require(); virtual() se nedá použít k vložení dokumentu, který je sám PHP skriptem.

II. Funkce pro práci s poli

Tyto funkce vám umožňují manipulovat a interagovat různými způsoby s poli. Pole jsou nezbytná pro ukládání a práci se sadami proměnných.

Podporována jsou jednoduchá a vícerozměrná pole; vytvářet se dají uživatelsky i jako výstup funkce. Existují databázové funkce na plnění polí výsledky databázových dotazů, a několik dalších funkcí vrací pole.

Viz také: is_array(), explode(), implode(), split() a join().

Obsah
array_change_key_case -- Returns an array with all string keys lowercased or uppercased
array_chunk -- Split an array into chunks
array_count_values -- Spočítat všechny hodnoty v poli
array_diff -- Spočítat rozdíl polí
array_fill -- Fill an array with values
array_filter -- Filters elements of an array using a callback function
array_flip -- Prohodit klíče a hodnoty pole
array_intersect -- Spočítat průnik polí
array_key_exists -- Checks if the given key or index exists in the array
array_keys -- Vrátit všechny klíče pole
array_map -- Applies the callback to the elements of the given arrays
array_merge_recursive -- Rekurzivně sloučit dvě nebo více polí
array_merge -- Sloučit dvě nebo více polí
array_multisort -- Třídit více polí, nebo vícerozměrné pole
array_pad -- Doplnit pole hodnotou na určenou délku
array_pop -- Odstranit prvek z konce pole
array_push -- Přidat jeden nebo více prvků na konec pole
array_rand -- Vybrat náhodně jeden nebo více prvků pole
array_reduce -- Iteratively reduce the array to a single value using a callback function
array_reverse -- Vrátit pole s prvky v opačném pořadí
array_search -- Searches the array for a given value and returns the corresponding key if successful
array_shift -- Odstranit prvek ze začátku pole
array_slice -- Vytáhnout část pole
array_splice -- Odstranit část pole a nahradit ji něčím jiným
array_sum -- Calculate the sum of values in an array.
array_unique -- Odstranit z pole duplicitní hodnoty
array_unshift -- Připojit jeden nebo více prvků na začátek pole
array_values -- Vrátit všechny hodnoty v poli
array_walk -- Použít uživatelskou funkci na všechny prvky pole
array -- Vytvořit pole
arsort -- Třídit pole sestupně se zachováním klíčů
asort -- Třídit pole se zachováním indexů
compact -- Vytvořit pole obsahující proměnné a jejich hodnoty
count -- Spočítat prvky v proměnné
current -- Vrátit současný prvek pole
each -- Vrací další klíč/hodnota pár z pole
end -- Nastavit vnitřní ukazatel pole na jeho poslední prvek
extract -- Importovat proměnné z pole do symbolové tabulky
in_array -- Vrátit TRUE, pokud v poli existuje daná hodnota
key -- Fetch a key from an associative array
krsort -- Třídit pole sestupně podle klíčů
ksort -- Třídit pole podle klíčů
list -- Přiřadit hodnoty přoměnným jako kdyby byly polem
natcasesort -- Třídit pole s využitím algoritmu "přirozeného třídění" (case-insensitive)
natsort -- Třídit pole s využitím algoritmu "přirozeného třídění"
next -- Posunout interní ukazatel pole
pos -- Získat současný prvek pole
prev -- Rewind interní ukazatel pole
range -- Vytvořit pole obsahující rozsah integerů
reset -- Nastavit interní ukazatel pole na jeho první prvek
rsort -- Třídit pole sestupně
shuffle -- Zamíchat pole
sizeof -- Zjistit počet prvků v poli
sort -- Třídit pole
uasort -- Třídit pole pomocí uživatelsky definované porovnávací funkce se zachováním klíčů
uksort -- Třídit pole podle klíčů pomocí uživatelsky definovane porovnávací funkce
usort -- Třídit pole podle hodnot pomocí uživatelsky definované porovnávací funkce

array_change_key_case

(PHP 4 >= 4.2.0)

array_change_key_case -- Returns an array with all string keys lowercased or uppercased

Description

array array_change_key_case ( array input [, int case])

array_change_key_case() changes the keys in the input array to be all lowercase or uppercase. The change depends on the last optional case parameter. You can pass two constants there, CASE_UPPER and CASE_LOWER. The default is CASE_LOWER. The function will leave number indices as is.

Příklad 1. array_change_key_case() example

$input_array = array("FirSt" => 1, "SecOnd" => 4);
print_r(array_change_key_case($input_array, CASE_UPPER));

The printout of the above program will be:

Array ( [FIRST] => 1 [SECOND] => 2 )

array_chunk

(PHP 4 >= 4.2.0)

array_chunk -- Split an array into chunks

Description

array array_chunk ( array input, int size [, bool preserve_keys])

array_chunk() splits the array into several arrays with size values in them. You may also have an array with less values at the end. You get the arrays as members of a multidimensional array indexed with numbers starting from zero.

By setting the optional preserve_keys parameter to TRUE, you can force PHP to preserve the original keys from the input array. If you specify FALSE new number indices will be used in each resulting array with indices starting from zero. The default is FALSE.

Příklad 1. array_chunk() example

$input_array = array('a', 'b', 'c', 'd', 'e');
print_r(array_chunk($input_array, 2));
print_r(array_chunk($input_array, 2, TRUE));

The printout of the above program will be:

Array ( [0] => Array ( [0] => a [1] => b ) [1] => Array ( [0] => c [1] => d ) [2] => Array ( [0] => e ) ) Array ( [0] => Array ( [0] => a [1] => b ) [1] => Array ( [2] => c [3] => d ) [2] => Array ( [4] => e ) )

array_count_values

(PHP 4 )

array_count_values -- Spočítat všechny hodnoty v poli

Popis

array array_count_values ( array input)

array_count_values() vrací pole používající hodnoty z input jako klíče a jejich četnosti v input jako hodnoty.

Příklad 1. Ukázka array_count_values()

$array = array (1, "hello", 1, "world", "hello"); array_count_values ($array); // vrací array(1=>2, "hello"=>2, "world"=>1)

array_diff

(PHP 4 >= 4.0.1)

array_diff -- Spočítat rozdíl polí

Popis

array array_diff ( array array1, array array2 [, array ...])

array_diff() vrací pole obsahující všechny hodnoty z array1, které se nevyskytují v žádném z dalších argumentů. Klíče jsou zachovány.

Příklad 1. Ukázka array_diff()

$array1 = array ("a" => "green", "red", "blue"); $array2 = array ("b" => "green", "yellow", "red"); $result = array_diff ($array1, $array2);

$result obsahuje array ("blue");

Viz také: array_intersect().

array_fill

(PHP 4 >= 4.2.0)

array_fill -- Fill an array with values

Description

array array_fill ( int start_index, int num, mixed value)

array_fill() fills an array with num entries of the value of the value parameter, keys starting at the start_index parameter.

Příklad 1. array_fill() example

$a = array_fill(5, 6, 'banana');

$a now has the following entries using print_r():

Array ( [5] => banana [6] => banana [7] => banana [8] => banana [9] => banana [10] => banana )

array_filter

(PHP 4 >= 4.0.6)

array_filter -- Filters elements of an array using a callback function

Description

array array_filter ( array input [, mixed callback])

array_filter() returns an array containing all the elements of input filtered according a callback function. If the input is an associative array the keys are preserved.

Příklad 1. array_filter() example

function odd($var) { return ($var % 2 == 1); } function even($var) { return ($var % 2 == 0); } $array1 = array ("a"=>1, "b"=>2, "c"=>3, "d"=>4, "e"=>5); $array2 = array (6, 7, 8, 9, 10, 11, 12); echo "Odd :\n"; print_r(array_filter($array1, "odd")); echo "Even:\n"; print_r(array_filter($array2, "even"));

The printout of the program above will be:

Odd : Array ( [a] => 1 [c] => 3 [e] => 5 ) Even: Array ( [0] => 6 [2] => 8 [4] => 10 [6] => 12 )

Poznámka: Místo názvu funkce může použito pole obsahující odkaz na objekt a název metody.

Users may not change the array itself from the callback function. e.g. Add/delete an element, unset the array that array_filter() is applied to. If the array is changed, the behavior of this function is undefined.

See also array_map() and array_reduce().

array_flip

(PHP 4 )

array_flip -- Prohodit klíče a hodnoty pole

Popis

array array_flip ( array trans)

array_flip() pole s prohozenými klíči a hodnotami.

Příklad 1. Ukázka array_flip()

$trans = array_flip ($trans); $original = strtr ($str, $trans);

array_intersect

(PHP 4 >= 4.0.1)

array_intersect -- Spočítat průnik polí

Popis

array array_intersect ( array array1, array array2 [, array ...])

array_intersect() vrací pole obsahující všechny hodnoty z array1, které se vyskytují ve všech argumentech. Klíče jsou zachovány.

Příklad 1. Ukázka array_intersect()

$array1 = array ("a" => "green", "red", "blue"); $array2 = array ("b" => "green", "yellow", "red"); $result = array_intersect ($array1, $array2);

$result obsahuje array ("a" => "green", "red");

Viz také: array_diff().

array_key_exists

(PHP 4 >= 4.1.0)

array_key_exists -- Checks if the given key or index exists in the array

Description

bool array_key_exists ( mixed key, array search)

array_key_exists() returns TRUE if the given key is set in the array. key can be any value possible for an array index.

Příklad 1. array_key_exists() example

$search_array = array("first" => 1, "second" => 4); if (array_key_exists("first", $search_array)) { echo "The 'first' element is in the array"; }

Poznámka: The name of this function is key_exists() in PHP version 4.0.6.

array_keys

(PHP 4 )

array_keys -- Vrátit všechny klíče pole

Popis

array array_keys ( array input [, mixed search_value])

array_keys() vrací klíče, numerické i textové, z pole input.

Pokud je přítomen volitelný argument search_value, vrací pouze klíče této hodnoty. Jinak vrací všechny klíče z pole input.

Příklad 1. Ukázka array_keys()

$array = array (0 => 100, "color" => "red"); array_keys ($array); // vrací array (0, "color") $array = array ("blue", "red", "green", "blue", "blue"); array_keys ($array, "blue"); // vrací array (0, 3, 4) $array = array ("color" => array("blue", "red", "green"), "size" => array("small", "medium", "large")); array_keys ($array); // vrací array ("color", "size")

Poznámka: Tato funkce byla přidána v PHP 4, dále je uvedena implementace pro ty, kteří stále používají PHP 3.
Příklad 2. Implementace array_keys() pro uživatele PHP 3
function array_keys ($arr, $term="") {
    $t = array();
    while (list($k,$v) = each($arr)) {
        if ($term && $v != $term)
            continue;
            $t[] = $k;
        }
        return $t;
}

Viz také: array_values().

array_map

(PHP 4 >= 4.0.6)

array_map -- Applies the callback to the elements of the given arrays

Description

array array_map ( mixed callback, array arr1 [, array arr2...])

array_map() returns an array containing all the elements of arr1 after applying the callback function to each one. The number of parameters that the callback function accepts should match the number of arrays passed to the array_map()

bool array_multisort ( array ar1 [, mixed arg [, mixed ... [, array ...]]])

array_multisort() se dá využít k třídění několika polí najednou nebo k třídění vícerozměrného pole XXX according by one of more dimensions. Při třídění udržuje asociace klíčů.

Vstupní pole jsou manipulována jako sloupce tabulky, která se má třídit podle řádků - připomíná to funkcionalitu SQL klauzule ORDER BY. První pole je to, podle kterého se bude třídit. Řádky (hodnoty) v tomto poli that compare the same are sorted by the next input array, and so on.

Struktura argumentů této funkce je trochu neobvyklá, ale pružná. První argument musí být pole. Každý další argument může být buď pole nebo jeden z příznak z následujících seznamů:

Příznaky směru třídění:

SORT_ASC - třídit vzestupně
SORT_DESC - třídit sestupně

Příznaky typu třídění:

SORT_REGULAR - porovnávat položky normálně
SORT_NUMERIC - porovnávat položky číselně
SORT_STRING - porovnávat položky jako řetězce

Po každém poli můžete specifikovat jeden příznak každého typu. Příznaky třídění specifikované po každém poli platí pouze pro toto pole - pro další pole se resetují na defaultní SORT_ASC a SORT_REGULAR.

Při úspěchu vrací TRUE, při selhání FALSE.

Příklad 1. Třídění více polí

$ar1 = array ("10", 100, 100, "a"); $ar2 = array (1, 3, "2", 1); array_multisort ($ar1, $ar2);

V této ukázce bude po setřídění první pole obsahovat 10, "a", 100, 100. Druhé pole bude obsahovat 1, 1, 2, "3". Položky druhého pole odpovídající identickým položkám v prvním poli (100 a 100) byly také setříděny.

Příklad 2. Třídění vícerozměrného pole

$ar = array (array ("10", 100, 100, "a"), array (1, 3, "2", 1)); array_multisort ($ar[0], SORT_ASC, SORT_STRING, $ar[1], SORT_NUMERIC, SORT_DESC);

V této ukázce bude po setřídění první pole obsahovat 10, 100, 100, "a" (bylo tříděno vzestupně jako řetězce) a druhé pole bude obsahovat 1, 3, "2", 1 (tříděno jako čísla, sestupně).

array_pad

(PHP 4 )

array_pad -- Doplnit pole hodnotou na určenou délku

Popis

array array_pad ( array input, int pad_size, mixed pad_value)

array_pad() vrací kopii pole input doplněnou na velikost pad_size hodnotou pad_value. Pokud je pad_size kladná, pole je doplněno zprava, pokud je negativní, zleva. Pokud je absolutní hodnota pad_size menší nebo rovna velikosti input, k doplnění nedojde.

Příklad 1. Ukázka array_pad()

$input = array (12, 10, 9); $result = array_pad ($input, 5, 0); // výsledek je array (12, 10, 9, 0, 0) $result = array_pad ($input, -7, -1); // výsledek je array (-1, -1, -1, -1, 12, 10, 9) $result = array_pad ($input, 2, "noop"); // nedoplněno

array_pop

(PHP 4 )

array_pop -- Odstranit prvek z konce pole

Popis

mixed array_pop ( array array)

array_pop() odstraní a vrátí poslední hodnotu pole array, čímž ho zkrátí o jeden prvek.

Příklad 1. Ukázka array_pop()

$stack = array ("orange", "apple", "raspberry"); $fruit = array_pop ($stack);

$stack má teď pouze dva prvky: "orange" a "apple", a $fruit obsahuje "raspberry".

Viz také: array_push(), array_shift() a array_unshift().

array_push

(PHP 4 )

array_push -- Přidat jeden nebo více prvků na konec pole

Popis

int array_push ( array array, mixed var [, mixed ...])

array_push() připojuje předané proměnné na konec array. Délka array se zvětšuje o počet přidaných proměnných. Účinek je stejný jako:

$array[] = $var;
opakované pro každou var.

Vrací nový počet prvků v poli.

Příklad 1. Ukázka array_push()

$stack = array (1, 2); array_push ($stack, "+", 3);

Výsledkem této ukázky by byl $stack obsahující 4 prvky: 1, 2, "+" a 3.

Viz také: array_pop(), array_shift() a array_unshift().

array_rand

(PHP 4 )

array_rand -- Vybrat náhodně jeden nebo více prvků pole

Popis

mixed array_rand ( array input [, int num_req])

array_rand() je poměrně užitečná, když chcete z pole vybrat náhodně jednu nebo více hodnot. Přijímá pole input a volitelný argument num_req, který určuje, kolik položek chcete. Jeho defaultní hodnota je 1.

Pokud vybíráte pouze jednu položku, array_rand() vrací klíč náhodné položky. Jinak vrací pole klíčů náhodně vybraných položek. Takto můžete vybírat náhodně hodnoty i klíče.

Nezapomeňte inicializovat generátor náhodných čísel pomocí srand().

Příklad 1. Ukázka array_rand()

srand ((double) microtime() * 10000000); $input = array ("Neo", "Morpheus", "Trinity", "Cypher", "Tank"); $rand_keys = array_rand ($input, 2); print $input[$rand_keys[0]]."\n"; print $input[$rand_keys[1]]."\n";

array_reduce

(PHP 4 >= 4.0.5)

array_reduce -- Iteratively reduce the array to a single value using a callback function

Description

mixed array_reduce ( array input, mixed callback [, int initial])

array_reduce() applies iteratively the callback function to the elements of the array input, so as to reduce the array to a single value. If the optional initial is available, it will be used at the beginning of the process, or as a final result in case the array is empty.

Příklad 1. array_reduce() example

function rsum($v, $w) { $v += $w; return $v; } function rmul($v, $w) { $v *= $w; return $v; } $a = array(1, 2, 3, 4, 5); $x = array(); $b = array_reduce($a, "rsum"); $c = array_reduce($a, "rmul", 10); $d = array_reduce($x, "rsum", 1);

This will result in $b containing 15, $c containing 1200 (= 1*2*3*4*5*10), and $d containing 1.

See also array_filter() and array_map().

array_reverse

(PHP 4 )

array_reverse -- Vrátit pole s prvky v opačném pořadí

Popis

array array_reverse ( array array [, bool preserve_keys])

array_reverse() takes input array and returns a new array with the order of the elements reversed, preserving the keys if preserve_keys is TRUE.

Příklad 1. array_reverse() example

$input = array ("php", 4.0, array ("green", "red")); $result = array_reverse ($input); $result_keyed = array_reverse ($input, true);

$result teď obsahuje array (array ("green", "red"), 4.0, "php"). Ale $result2[0] je stále "php".

Poznámka: Druhý argument byl přidán v PHP 4.0.3.

array_search

(PHP 4 >= 4.0.5)

array_search -- Searches the array for a given value and returns the corresponding key if successful

Description

mixed array_search ( mixed needle, array haystack [, bool strict])

Searches haystack for needle and returns the key if it is found in the array, FALSE otherwise.

Poznámka: Prior to PHP 4.2.0, array_search() returns NULL on failure instead of FALSE.

If the optional third parameter strict is set to TRUE then the array_search() will also check the types of the needle in the haystack.

Varování

Tato funkce může vracet booleovskou hodnotu FALSE, ale také nebooleovskou hodnotu odpovídající ohodnocení FALSE, například 0 nebo "". Čtěte prosím sekci o typu Boolean, kde najdete více informací. Pro testování návratové hodnoty této funkce použijte operátor ===.

See also array_keys() and in_array().

array_shift

(PHP 4 )

array_shift -- Odstranit prvek ze začátku pole

Popis

mixed array_shift ( array array)

array_shift() vrací první položku array a odstraní ji, čímž zkrátí array o jeden prvek a ostatní posune dolů.

Příklad 1. Ukázka array_shift()

$args = array ("-v", "-f"); $opt = array_shift ($args);

$args teď má jeden prvek: "-f" a $opt je "-v".

Viz také: array_unshift(), array_push() a array_pop().

array_slice

(PHP 4 )

array_slice -- Vytáhnout část pole

Popis

array array_slice ( array array, int offset [, int length])

array_slice() vrací sekvenci prvků array určených argumenty offset a length.

Pokud je offset kladný, tato sekvence začne offset položek od začátku array. Pokud je offset záporný, tato sekvence začne tolik položek od konce array.

Pokud je length kladná, tato sekvence bude obsahovat tolik prvků. Pokud je length záporná, tato sekvence skončí tolik prvků od konce array. Pokud length vynecháte, tato sekvence bude obsahovat všechny prvky array od offset do konce.

Příklad 1. Ukázka array_slice()

$input = array ("a", "b", "c", "d", "e"); $output = array_slice ($input, 2); // returns "c", "d", and "e" $output = array_slice ($input, 2, -1); // returns "c", "d" $output = array_slice ($input, -2, 1); // returns "d" $output = array_slice ($input, 0, 3); // returns "a", "b", and "c"

Viz také: array_splice().

array_splice

(PHP 4 )

array_splice -- Odstranit část pole a nahradit ji něčím jiným

Popis

array array_splice ( array input, int offset [, int length [, array replacement]])

array_splice() odstraňuje prvky pole input určené argumenty offset a length, a případně je nahrazuje prvky volitelného argumentu (pole) replacement.

Pokud je offset kladný, tato odstraněná část začne offset položek od začátku array. Pokud je offset záporný, začne tolik položek od konce array.

Pokud vynecháte length, array_splice() odstraní všechno od offset do konce pole. Pokud je length kladná, odstraní se právě tolik prvků. Pokud je length záporná, konec odstraněné části bude právě tolik prvků od konce pole. Tip: k odstranění všech prvků od offset do konce pole při současně určeném argumentu replacement použijte jako length count($input).

Pokud zadáte replacement pole, odstraněné prvky se nahradí prvky tohoto pole. Pokud argumenty offset a length definovány tak, že se nic neodstraní, prvky pole replacement se vloží na místo určené argumentem offset. Tip: pokud je replacement jen jedna hodnota, není nutno ji umisťovat do array(), ledaže chcete, aby tato položka byla opravdu pole.

Následující volání jsou ekvivalentní:

array_push ($input, $x, $y) array_splice ($input, count ($input), 0, array ($x, $y)) array_pop ($input) array_splice ($input, -1) array_shift ($input) array_splice ($input, 0, 1) array_unshift ($input, $x, $y) array_splice ($input, 0, 0, array ($x, $y)) $a[$x] = $y array_splice ($input, $x, 1, $y)

Vrací pole odstraněných prvků.

Příklad 1. Ukázky array_splice()

$input = array ("red", "green", "blue", "yellow"); array_splice ($input, 2); // $input is now array ("red", "green") array_splice ($input, 1, -1); // $input is now array ("red", "yellow") array_splice ($input, 1, count($input), "orange"); // $input is now array ("red", "orange") array_splice ($input, -1, 1, array("black", "maroon")); // $input is now array ("red", "green", // "blue", "black", "maroon")

Viz také: array_slice().

array_sum

(PHP 4 >= 4.0.4)

array_sum -- Calculate the sum of values in an array.

Description

mixed array_sum ( array array)

array_sum() returns the sum of values in an array as an integer or float.

Příklad 1. array_sum() examples

$a = array(2, 4, 6, 8); echo "sum(a) = ".array_sum($a)."\n"; $b = array("a"=>1.2,"b"=>2.3,"c"=>3.4); echo "sum(b) = ".array_sum($b)."\n";

The printout of the program above will be:

sum(a) = 20 sum(b) = 6.9

Poznámka: PHP versions prior to 4.0.6 modified the passed array itself and converted strings to numbers (which most of the time converted them to zero, depending on their value).

array_unique

(PHP 4 >= 4.0.1)

array_unique -- Odstranit z pole duplicitní hodnoty

Popis

array array_unique ( array array)

array_unique() přijímá pole array a vrací nové pole bez duplicitních hodnot. Klíče jsou zachovány.

Příklad 1. Ukázka array_unique()

$input = array ("a" => "green", "red", "b" => "green", "blue", "red"); $result = array_unique ($input);

$result teď obsahuje array ("a" => "green", "red", "blue");.

array_unshift

(PHP 4 )

array_unshift -- Připojit jeden nebo více prvků na začátek pole

Popis

int array_unshift ( array array, mixed var [, mixed ...])

array_unshift() připojí předané prvky na začátek array. Všechny prvky jsou přidány jako celek, čili přidané prvky si zachovávají pořadí.

vrací nový počet prvků v array.

Příklad 1. Ukázka array_unshift()

$queue = array ("p1", "p3"); array_unshift ($queue, "p4", "p5", "p6");

$queue bude mít 5 prvků: "p4", "p5", "p6", "p1" a "p3".

Viz také: array_shift(), array_push() a array_pop().

array_values

(PHP 4 )

array_values -- Vrátit všechny hodnoty v poli

Popis

array array_values ( array input)

array_values() vrací všechny hodnoty pole input.

Příklad 1. Ukázka array_values()

$array = array ("size" => "XL", "color" => "gold"); array_values ($array); // vrátí array ("XL", "gold")

Poznámka: Tato funkce byla přidána v PHP 4, následuje implementace pro ty, kdo stále používají PHP 3.
Příklad 2. Implementace array_values() pro uživatele PHP 3
function array_values ($arr) {
    $t = array();
    while (list($k, $v) = each ($arr)) {
        $t[] = $v;
        return $t;
    }
}

array_walk

(PHP 3>= 3.0.3, PHP 4 )

array_walk -- Použít uživatelskou funkci na všechny prvky pole

Popis

int array_walk ( array arr, string func, mixed userdata)

Aplikuje funkci func na všechny prvky pole arr. Funkci func se jako první argument předá hodnota a jako druhý klíč. Pokud je přítomen argument userdata, bude uživatelské funkci předán jako třetí argument.

Pokud func vyžaduje více než dva nebo tři argumenty (v závislosti na userdata), pro každé volání func z array_walk() se vygeneruje varování. Tato varování se dají potlačit přidáním znaku '@' před volání array_walk() nebo pomocí error_reporting().

Poznámka: Pokud func potřebuje pracovat přímo s daným polem, první argument func se musí předávat odkazem. Všechny změny těchto hodnot se pak promítnou přímo v arr.

Poznámka: Druhý a třetí argument func byly přidány v PHP 4.0.

V PHP 4 je třeba volat podle potřeby reset(), protože array_walk() sama vstupní pole neresetuje.

Příklad 1. Ukázka array_walk()

$fruits = array ("d"=>"lemon", "a"=>"orange", "b"=>"banana", "c"=>"apple"); function test_alter (&$item1, $key, $prefix) { $item1 = "$prefix: $item1"; } function test_print ($item2, $key) { echo "$key. $item2<br>\n"; } array_walk ($fruits, 'test_print'); reset ($fruits); array_walk ($fruits, 'test_alter', 'fruit'); reset ($fruits); array_walk ($fruits, 'test_print');

Viz také: each() a list().

array

(unknown)

array -- Vytvořit pole

Popis

array array ( [mixed ...])

Vrací pole argumentů. Argumentům může být přiřazen index pomocí operátoru =>.

Poznámka: array() je jazykový konstrukt používaný k reprezentaci polí, nikoliv běžná funkce.

Syntaxe "index => hodnota", s čárko jako oddělovačem, definuje indexy a hodnoty. Index může být řetězec nebo číslo. Pokud se index vynechá, automaticky se generuje číselný index začínající na 0. Pokud je index integer, další generovaný index bude nejvyšší celočíselný index + 1. Pozn.: pokud jsou definovány dva identické indexy, první se přepíše posledním.

Následující ukázka demonstruje jak vytvořit dvourozměrné pole, jak určit klíče v asociativních polích, a jak přeskakovat číselné indexy v normálních polích.

Příklad 1. Ukázka array()

$fruits = array ( "fruits" => array ("a"=>"orange", "b"=>"banana", "c"=>"apple"), "numbers" => array (1, 2, 3, 4, 5, 6), "holes" => array ("first", 5 => "second", "third") );

Příklad 2. Automatický index a array()

$array = array( 1, 1, 1, 1, 1, 8=>1, 4=>1, 19, 3=>13); print_r($array);
výstup bude následující:

Array
(
    [0] => 1
    [1] => 1
    [2] => 1
    [3] => 13
    [4] => 1
    [8] => 1
    [9] => 19
)

Index 3 je definován dvakrát, a podrží si poslední hodnotu 13. Index 4 je definován po indexu 8 a další generovaný index (hodnota 19) je 9, protože nejvyšší index byl 8.

Tato ukázka vytvoří pole číslované od 1.

Příklad 3. Index začínající 1 s array()

$firstquarter = array(1 => 'January', 'February', 'March'); print_r($firstquarter);
toto bude výstup:

Array
(
    [1] => 'January'
    [2] => 'February'
    [3] => 'March'
)

Viz také: list().

arsort

(PHP 3, PHP 4 )

arsort -- Třídit pole sestupně se zachováním klíčů

Popis

void arsort ( array array [, int sort_flags])

arsort() třídí pole tak, že indexy pole si zachovávají korelace s prvky, se kterými jsou asociovány. Toto je užitečné hlavně při třídění asociativních polí, kde je pořadí prvků signifikantní.

Příklad 1. Ukázka arsort()

$fruits = array ("d"=>"lemon", "a"=>"orange", "b"=>"banana", "c"=>"apple"); arsort ($fruits); reset ($fruits); while (list ($key, $val) = each ($fruits)) { echo "$key = $val\n"; }

Tato ukázka zobrazí:

fruits[a] = orange
fruits[d] = lemon
fruits[b] = banana
fruits[c] = apple

Ovoce bylo sestupně setříděno podle abecedy, a indexy asociované s jednotlivými prvky byly zachovány.

Chování třídění můžete upravit pomocí volitelného argumentu sort_flags, detaily viz sort().

Viz také: asort(), rsort(), ksort() a sort().

asort

(PHP 3, PHP 4 )

asort -- Třídit pole se zachováním indexů

Popis

void asort ( array array [, int sort_flags])

asort() třídí pole tak, že si indexy zachovají corelace s prvky, se kterými jsou spojeny. To je užitečné hlavně při třídění asociativních polí, u kterých je pořadí prvků signifikantní.

Příklad 1. Ukázka asort()

$fruits = array ("d"=>"lemon", "a"=>"orange", "b"=>"banana", "c"=>"apple"); asort ($fruits); reset ($fruits); while (list ($key, $val) = each ($fruits)) { echo "$key = $val\n"; }

Tato ukázka zobrazí:

fruits[c] = apple
fruits[b] = banana
fruits[d] = lemon
fruits[a] = orange

Ovoce bylo setříděno podle abecedy a indexy spojené s jednotlivými prvky byly zachovány.

Chování třídění můžete upravit pomocí volitelného argumentu sort_flags, detaily viz sort().

Viz také: arsort(), rsort(), ksort() a sort().

compact

(PHP 4 )

compact -- Vytvořit pole obsahující proměnné a jejich hodnoty

Popis

array compact ( mixed varname [, mixed ...])

compact() přijímá proměnný počet argumentů. Každý argument může být buď řetězec obsahující název proměnné nebo pole názvů proměnných. Toto pole může také obsahovat pole názvů proměnnýchů; compact() je rekurzivně zpracuje.

Pro každý z řetězců compact() vyhledá v aktivní symbolové tabulce proměnnou tohoto jména a přidá ji do výsledného pole tak, že název této proměnné se stane klíčem a obsah této proměnné hodnotou tohoto klíče. Stručně řečeno, dělá pravý opak toho, co extract(). Vrací pole obsahující všechny tyto proměnné.

Řetězce, které neobsahují názvy platných proměnných se přeskočí.

Příklad 1. Ukázka compact()

$city = "San Francisco"; $state = "CA"; $event = "SIGGRAPH"; $location_vars = array ("city", "state"); $result = compact ("event", "nothing_here", $location_vars);

$result bude array ("event" => "SIGGRAPH", "city" => "San Francisco", "state" => "CA").

Viz také: extract().

count

(PHP 3, PHP 4 )

count -- Spočítat prvky v proměnné

Popis

int count ( mixed var)

Vrací počet prvků v var, která je typicky pole (jelikož všechno ostatní má jeden prvek).

Vrací 1, pokud var není pole.

Vrací 0, pokud var není inicializována.

Varování

count() vrací 0 pro proměnné, které nejsou inicializovány, ale vrací také 0 pro proměnné, které obsahují prázdné pole. Pokud potřebujete zjistit, jestli dotyčná proměnná existuje, použijte isset().

Příklad 1. Ukázka count()

$a[0] = 1; $a[1] = 3; $a[2] = 5; $result = count ($a); //$result == 3

Viz také: sizeof(), isset() a is_array().

current

(PHP 3, PHP 4 )

current -- Vrátit současný prvek pole

Popis

mixed current ( array array)

Každé pole má vnitřní ukazatel na jeho "současny" prvek, který se inicializuje na první prvek vložený do tohoto pole.

current() vrací prvek, na který tento interní ukazatel právě ukazuje. Nijak tento ukazatel nemění. Pokud teto vnitřní ukazatel ukazuje za konec seznamu prvků, current() returns FALSE.

Varování

Pokud toto pole obsahuje prázdné prvky (0 nebo "", prázdný řetězec), tato funkce pro tyto prvky také vrátí FALSE. Je proto nemožné určit pomocí current(), jestli jste opravdu na konci pole. To properly traverse an array that may contain empty elements, use the each() function.

Viz také: end(), next(), prev() a reset().

each

(PHP 3, PHP 4 )

each -- Vrací další klíč/hodnota pár z pole

Popis

array each ( array array)

Vrací současný klíč/hodnota pár z pole array a posune interní ukazatel pole. Tento pár se vrací jako pole čtyř prvků s klíči 0, 1, key a value. Prvky 0 a key obsahují název klíče tohoto prvku pole a 1 a value obsahují hodnotu.

Pokud interní ukazatel pole ukazuje za konec tohoto pole, each() vrací FALSE.

Příklad 1. Ukázky each()

$foo = array ("bob", "fred", "jussi", "jouni", "egon", "marliese"); $bar = each ($foo);

$bar teď obsahuje následující klíč/hodnota páry:

0 => 0
1 => 'bob'
key => 0
value => 'bob'

$foo = array ("Robert" => "Bob", "Seppo" => "Sepi"); $bar = each ($foo);

$bar teď obsahuje následující klíč/hodnota páry:

0 => 'Robert'
1 => 'Bob'
key => 'Robert'
value => 'Bob'

each() se většinou používa s list() k průchodu polem, např. $HTTP_POST_VARS:

Příklad 2. Průchod $HTTP_POST_VARS pomocí each()

echo "Hodnoty odeslané metodou POST:<br>"; reset ($HTTP_POST_VARS); while (list ($key, $val) = each ($HTTP_POST_VARS)) { echo "$key => $val<br>"; }

Poté, co proběhne each(), se interní ukazatel pole posune na další prvek pole nebo zůstane na posledním prvku pole, pokud dojde na konec.

Viz také: key(), list(), current(), reset(), next() a prev().

end

(PHP 3, PHP 4 )

end -- Nastavit vnitřní ukazatel pole na jeho poslední prvek

Popis

mixed end ( array array)

end() posune vnitřní ukazatel pole array na jeho poslední prvek a vrací tento prvek.

Viz také: current(), each(), end(), next() a reset().

extract

(PHP 3>= 3.0.7, PHP 4 )

extract -- Importovat proměnné z pole do symbolové tabulky

Popis

int extract ( array var_array [, int extract_type [, string prefix]])

Tato funkce se používá k importu proměnných z pole do aktivní symbolové tabulky. Přijímá pole var_array; z klíčů vytváří názvy proměnných a z hodnot hodnoty těchto proměnných. Vytváří jednu proměnnou z každého klíč/hodnota páru (s ohledem na argumenty extract_type a prefix).

Poznámka: Od PHP 4.0.5 tato funkce vrací počet extrahovaných proměnných.

extract() ověřuje, jestli všechny klíče tvoří platné názvy proměnných, a také jestli nekolidují s proměnnými existujícími v aktivní symbolové tabulce. Způsob, jakým se nakládá s neplatnými/numerickými klíči a kolizemi závisí na extract_type. Ten může mít jednu z následujících hodnot.

EXTR_OVERWRITE: Pokud existuje kolize, přepsat existující proměnnou.
EXTR_SKIP: Pokud existuje kolize, nepřepsat existující proměnnou.
EXTR_PREFIX_SAME: Pokud existuje kolize, předřadit před název nové proměnné prefix.
EXTR_PREFIX_ALL: Opatřit prefixem prefix všechny názvy proměnných. Od PHP 4.0.5 toto zahrnuje i číselné indexy.
EXTR_PREFIX_INVALID: Prefixem prefix opatřit pouze neplatné/číselné názvy proměnných. Tento příznak byl přidán v PHP 4.0.5.

Defaultní extract_type je EXTR_OVERWRITE.

Pozn.: prefix se vyžaduje pouze pokud je extract_type EXTR_PREFIX_SAME, EXTR_PREFIX_ALL nebo EXTR_PREFIX_INVALID. Pokud výsledný název (vč. prefixu) není platný název proměnné, nenaimportuje se do symbolové tabulky.

extract() vrací počet proměnných úspěšně naimportovaných do symbolové tabulky.

Možné využití extract() je import proměnných do symbolové tabulky z asociativního pole vráceného wddx_deserialize().

Příklad 1. Ukázka extract()

<?php /* Předpokládejme, že $var_array je pole vrácené z wddx_deserialize */ $size = "large"; $var_array = array ("color" => "blue", "size" => "medium", "shape" => "sphere"); extract ($var_array, EXTR_PREFIX_SAME, "wddx"); print "$color, $size, $shape, $wddx_size\n"; ?>

Výše uvedená ukázka vytiskne:

blue, large, sphere, medium

$size se nepřepsala, protože bylo specifikováno EXTR_PREFIX_SAME, tudíž se vytvořila proměnná $wddx_size. Pokud by bylo zadáno EXTR_SKIP, nevytvořila by se ani $wddx_size. EXTR_OVERWRITE by způsobilo přepsání hodnoty $size na "medium", a EXTR_PREFIX_ALL by vytvořilo nové proměnné pojmenované $wddx_color, $wddx_size a $wddx_shape.

U PHP verzí nižších než 4.0.5 musíte použít asociativní pole.

Viz také: compact().

in_array

(PHP 4 )

in_array -- Vrátit TRUE, pokud v poli existuje daná hodnota

Popis

bool in_array ( mixed needle, array haystack, bool strict)

Hledá v haystack needle a pokud ji najde, vrací TRUE, jinak FALSE.

Pokud je třetí argument strict TRUE, in_array() také kontroluje typ needle v haystack.

Příklad 1. Ukázka in_array()

$os = array ("Mac", "NT", "Irix", "Linux"); if (in_array ("Irix", $os)){ print "Got Irix"; }

Příklad 2. Ukázka in_array() s argumentem strict

// Výstup bude: 1.13 found with strict check

key

(PHP 3, PHP 4 )

key -- Fetch a key from an associative array

Popis

mixed key ( array array)

key() vrací index současného prvku pole.

Viz také: current() a next().

krsort

(PHP 3>= 3.0.13, PHP 4 )

krsort -- Třídit pole sestupně podle klíčů

Popis

int krsort ( array array [, int sort_flags])

Třídí pole sestupně podle klíčů se zachování asociací indexů. To je užitečné hlavně při práci s asociativními poli.

Příklad 1. krsort() example

$fruits = array ("d"=>"lemon", "a"=>"orange", "b"=>"banana", "c"=>"apple"); krsort ($fruits); reset ($fruits); while (list ($key, $val) = each ($fruits)) { echo "$key -> $val\n"; }

Tato ukázka vytiskne:

fruits[d] = lemon
fruits[c] = apple
fruits[b] = banana
fruits[a] = orange

Vlastnosti třídění lze upravit pomocí volitelného argumentu sort_flags, detaily viz sort().

Viz také: asort(), arsort(), ksort(), sort(), natsort() a rsort().

ksort

(PHP 3, PHP 4 )

ksort -- Třídit pole podle klíčů

Popis

int ksort ( array array [, int sort_flags])

Třídí pole podle klíčů se zachování asociací indexů. To je užitečné hlavně při práci s asociativními poli.

Příklad 1. ksort() example

$fruits = array ("d"=>"lemon", "a"=>"orange", "b"=>"banana", "c"=>"apple"); ksort ($fruits); reset ($fruits); while (list ($key, $val) = each ($fruits)) { echo "$key -> $val\n"; }

Tato ukázka vytiskne:

fruits[a] = orange
fruits[b] = banana
fruits[c] = apple
fruits[d] = lemon

Vlastnosti třídění lze upravit pomocí volitelného argumentu sort_flags, detaily viz sort().

Viz také: asort(), arsort(), sort(), natsort() a rsort().

Poznámka: Druhý argument byl přidán v PHP 4.

list

(unknown)

list -- Přiřadit hodnoty přoměnným jako kdyby byly polem

Popis

void list ( mixed ...)

Stejně jako array(), list() vlastně není funkce, ale jazykový konstrukt. Používá se k přiřazení hodnot více proměnným v jedné operaci.

Příklad 1. Ukázka list()

<table> <tr> <th>Employee name</th> <th>Salary</th> </tr> <?php $result = mysql ($conn, "SELECT id, name, salary FROM employees"); while (list ($id, $name, $salary) = mysql_fetch_row ($result)) { print (" <tr>\n". " <td><a href=\"info.php3?id=$id\">$name</a></td>\n". " <td>$salary</td>\n". " </tr>\n"); } ?> </table>

Viz také: each() a array().

natcasesort

(PHP 4 )

natcasesort -- Třídit pole s využitím algoritmu "přirozeného třídění" (case-insensitive)

Popis

void natcasesort ( array array)

Tato funkce implementuje srovnávací algoritmus který třídí alfanumerické řetězce stejným způsobem jako člověk, toto se popisuje jako "přirozené třídění".

natcasesort() je case-insensitive verze natsort(). Ukázka rozdílu mezi tímto algoritmem a běžným počítačovým tříděním řetězců viz natsort().

Více informací viz stránka Martina Poola Natural Order String Comparison.

Viz také: sort(), natsort(), strnatcmp() and strnatcasecmp().

natsort

(PHP 4 )

natsort -- Třídit pole s využitím algoritmu "přirozeného třídění"

Popis

void natsort ( array array)

Tato funkce implementuje srovnávací algoritmus který třídí alfanumerické řetězce stejným způsobem jako člověk, toto se popisuje jako "přirozené třídění". Ukázka rozdílu mězi tímto algoritmem a běžnými počítačovými algoritmy pro řazení řetězců (např. sort()):

Příklad 1. Ukázka natsort()

$array1 = $array2 = array ("img12.png","img10.png","img2.png","img1.png"); sort($array1); echo "Standardní třídění\n"; print_r($array1); natsort($array2); echo "\nPřirozené třídění\n"; print_r($array2);

Výše uvedený kód vygeneruje následující výstup:

Standardní třídění
Array
(
    [0] => img1.png
    [1] => img10.png
    [2] => img12.png
    [3] => img2.png
)

Přirozené třídění
Array
(
    [3] => img1.png
    [2] => img2.png
    [1] => img10.png
    [0] => img12.png
)

Více informací viz stránka Martina Poola Natural Order String Comparison.

Viz také: natcasesort(), strnatcmp() a strnatcasecmp().

(PHP 3, PHP 4 )

next -- Posunout interní ukazatel pole

Popis

mixed next ( array array)

Vrací další prvek pole nebo FALSE, pokud prvky došly.

next() se chová jako current(), s jedním rozdílem: posouvá interní ukazatel pole o jeden prvek a vrací prvek, na který tento ukazatel ukazuje po posunu. To znamená, že vrací další prvek pole a posouvá interní ukazatel o jeden. Pokud by ukazatel po psunu ukazoval mimo pole, next() vrací FALSE.

Varování

Pokud toto pole obsahuje prázdné prvky, nebo prvky, jejichž index je 0, tato funkce vrátí FALSE i pro tyto prvky. Ke správnému průchodu polem, které může obsahovat prázdné prvky nebo prvky s indexem 0 použijte each().

Viz také: current(), end(), prev() a reset().

pos

(PHP 3, PHP 4 )

pos -- Získat současný prvek pole

Popis

mixed pos ( array array)

Toto je alias k current().

Viz také: end(), next(), prev() a reset().

(PHP 3, PHP 4 )

prev -- Rewind interní ukazatel pole

Popis

mixed prev ( array array)

Vrací prvek pole před tím prvkem, na který ukazuje interní ukazatel pole, nebo FALSE, pokud prvky došly.

Varování

Pokud toto pole obsahuje prázdné prvky, tato funkce vrátí FALSE i pro tyto prvky. Ke správnému průchodu polem, které může obsahovat prázdné prvky použijte each().

prev() se chová stejně jako next(), ale posouvá interní ukazatel pole o jedno místo zpátky místo dopředu.

Viz také: current(), end(), next() a reset().

range

(PHP 3>= 3.0.8, PHP 4 )

range -- Vytvořit pole obsahující rozsah integerů

Popis

array range ( int low, int high)

range() vrací pole integerů od low po high včetně.

Ukázka použití viz shuffle().

reset

(PHP 3, PHP 4 )

reset -- Nastavit interní ukazatel pole na jeho první prvek

Popis

mixed reset ( array array)

reset() přetočí interní ukazatel pole array na jeho první prvek.

reset() vrací hodnotu prvního prvku pole.

Viz také: current(), each(), next() a prev().

rsort

(PHP 3, PHP 4 )

rsort -- Třídit pole sestupně

Popis

void rsort ( array array [, int sort_flags])

Tato funkce sestupně třídí pole.

Příklad 1. Ukázka rsort()

$fruits = array ("lemon", "orange", "banana", "apple"); rsort ($fruits); reset ($fruits); while (list ($key, $val) = each ($fruits)) { echo "$key -> $val\n"; }

Tato ukázka zobrazí:

fruits[0] = orange
fruits[1] = lemon
fruits[2] = banana
fruits[3] = apple

void sort ( array array [, int sort_flags])

sort() třídí pole. Prvky se uspořádají od nejmenšího k největšímu.

Příklad 1. Ukázka sort()

<?php $fruits = array ("lemon", "orange", "banana", "apple"); sort ($fruits); reset ($fruits); while (list ($key, $val) = each ($fruits)) { echo "fruits[".$key."] = ".$val; } ?>

Tato ukázka zobrazí:

fruits[0] = apple
fruits[1] = banana
fruits[2] = lemon
fruits[3] = orange

Ovoce bylo seřazeno podle abecedy.

Vlastnosti třídění lze upravit pomocí volitelného argumentu sort_flags, který může nabývat těchto hodnot:

Typy třídění:

SORT_REGULAR - normální porovnávání
SORT_NUMERIC - numerické porovnávání
SORT_STRING - textové porovnávání

Viz také: arsort(), asort(), ksort(), natsort(), natcasesort(), rsort(), usort(), array_multisort() a uksort().

Poznámka: Druhý argument byl přidán v PHP 4.

uasort

(PHP 3>= 3.0.4, PHP 4 )

uasort -- Třídit pole pomocí uživatelsky definované porovnávací funkce se zachováním klíčů

Popis

void uasort ( array array, function cmp_function)

Tato funkce třídí pole tak, že si indexy uchovávají spojení s hodnotami. To je užitečné hlavně při třídění asociativních polí, kde je důležité pořadí prvků. Srovnávací funkce je uživatelsky definována.

Poznámka: Ukázky uživatelsky definovaných porovnávacích funkcí viz usort() a uksort().

Viz také: usort(), uksort(), sort(), asort(), arsort(), ksort() a rsort().

uksort

(PHP 3>= 3.0.4, PHP 4 )

uksort -- Třídit pole podle klíčů pomocí uživatelsky definovane porovnávací funkce

Popis

void uksort ( array array, function cmp_function)

Tato funkce třídí pole podle klíčů pomocí uživatelsky definované porovnávací funkce. Pokud potřebujete třídit pole podle komplikovanějších kritérií, měli byste použít tuto funkci.

Příklad 1. Ukázka uksort()

function cmp ($a, $b) { if ($a == $b) return 0; return ($a > $b) ? -1 : 1; } $a = array (4 => "four", 3 => "three", 20 => "twenty", 10 => "ten"); uksort ($a, "cmp"); while (list ($key, $value) = each ($a)) { echo "$key: $value\n"; }

Tato ukázka zobrazí:

20: twenty
10: ten
4: four
3: three

Viz také: usort(), uasort(), sort(), asort(), arsort(), ksort(), natsort() a rsort().

usort

(PHP 3>= 3.0.3, PHP 4 )

usort -- Třídit pole podle hodnot pomocí uživatelsky definované porovnávací funkce

Popis

void usort ( array array, string cmp_function)

Tato funkce třídí pole podle hodnot pomocí uživatelsky definované porovnávací funkce. Pokud potřebujete třídit pole podle komplikovanějších kritérií, měli byste použít tuto funkci.

Porovnávací funkce musí vrace integer menší než 0, 0, a větší než 0, pokud je první argument menší než, stejný, nebo větší než druhý argument. Pokud jsou dvě porovnávané hodnoty stejné, jejich pořadí v tříděném poli je nedefinováno.

Příklad 1. Ukázka usort()

function cmp ($a, $b) { if ($a == $b) return 0; return ($a > $b) ? -1 : 1; } $a = array (3, 2, 5, 6, 1); usort ($a, "cmp"); while (list ($key, $value) = each ($a)) { echo "$key: $value\n"; }

Tato ukázka zobrazí:

0: 6
1: 5
2: 3
3: 2
4: 1

Poznámka: V tomto jednoduchém případě by pochopitelně bylo vhodnější použít rsort().

Příklad 2. Ukázka usort() s vícerozměrným polem

function cmp ($a, $b) { return strcmp($a["fruit"],$b["fruit"]); } $fruits[0]["fruit"] = "lemons"; $fruits[1]["fruit"] = "apples"; $fruits[2]["fruit"] = "grapes"; usort($fruits, "cmp"); while (list ($key, $value) = each ($fruits)) { echo "\$fruits[$key]: " . $value["fruit"] . "\n"; }

Při třídění vícerozměrného pole $a a $b obsahují reference na první index pole.

Tato ukázka zobrazí:

$fruits[0]: apples
$fruits[1]: grapes
$fruits[2]: lemons

Varování

Použitá quicksort funkce v některých C knihovnách (např. na systémech Solaris) může způsobit zhroucení PHP, pokud porovnávací funkce nevrací konsistentní hodnoty.

Viz také: uasort(), uksort(), sort(), asort(), arsort(), ksort(), natsort() a rsort().

III. Aspell funkce

aspell() funkce umožňují ověřit hláskování slova a nabídnout možné opravy.

Poznámka: aspell funguje pouze s velmi starými (do přibližně .27.*) verzemi aspell knihovny. Tento modul, ani tyto verze aspell knihovny už nejsou podporovány. Pokud chcete v PHP použít kontrolu hláskování, použijte místo toho pspell. Využívá pspell knihovnu, a pracuje s novějšími verzemi aspellu.

Budete potřebovat aspell knihovnu dostupnou z: http://aspell.sourceforge.net/.

Obsah
aspell_check_raw -- Zkontrolovat slovo beze změny velikosti písmen nebo pokusů o ořezání
aspell_check -- Zkontrolovat slovo
aspell_new -- Načíst nový slovník
aspell_suggest -- Nabídnout možné hláskování slova

IV. BCMath funkce pro výpočty s libovolnou přesností

Tyto funkce jsou dostupné pouze pokud bylo PHP zkonfigurováno s --enable-bcmath.

Obsah
bcadd -- Sečíst dvě čísla s libovolnou přesností
bccomp -- Porovnat dvě čísla s libovolnou přesností
bcdiv -- Dělit dvě čísla s libovolnou přesností
bcmod -- Získat modulus čísla s libovolnou přesností
bcmul -- Vynásobit dvě čísla s libovolnou přesností
bcpow -- Umocnit jedno číslo na jiné s libovolnou přesností
bcscale -- Nastavit výchozí škálu pro všechny bc math funkce
bcsqrt -- Získat druhou odmocninu čísla s libovolnou přesností
bcsub -- Odečíst jedno číslo od druhého s libovolnou přesností

bcadd

(PHP 3, PHP 4 )

bcadd -- Sečíst dvě čísla s libovolnou přesností

Popis

string bcadd ( string left operand, string right operand [, int scale])

Přičte left operand k right operand a vrátí součet v řetězci. Volitelný argument scale se používá k určení počtu desetinných míst ve výsledku.

Viz také bcsub().

bccomp

(PHP 3, PHP 4 )

bccomp -- Porovnat dvě čísla s libovolnou přesností

string bcscale ( int scale)

Tato funkce nastaví výchozí škálu pro všechna následná volání bc math funkcí, ktera neudávají explicitně škálu přesnosti.

bcsqrt

(PHP 3, PHP 4 )

bcsqrt -- Získat druhou odmocninu čísla s libovolnou přesností

Popis

string bcsqrt ( string operand, int scale)

Vrátí druhou odmocninu argumentu operand. Volitelný argument scale se používá k určení počtu desetinných míst ve výsledku.

Viz také bcpow().

bcsub

(PHP 3, PHP 4 )

bcsub -- Odečíst jedno číslo od druhého s libovolnou přesností

Popis

string bcsub ( string left operand, string right operand [, int scale])

Odečte argument right operand od argumentu left operand a vrátí výsledek v řetězci. Volitelný argument scale se používá k určení počtu desetinných míst ve výsledku.

Viz také bcadd().

V. Kompresní funkce bzip2

Úvod

Funkce bzip2 se používají k transparentnímu čtení a zápisu souborů komprimovaných algoritmem bzip2 (.bz2).

Požadavky

Tento modul používá funkce z knihovny bzip2 od Juliana Sewarda.

Instalace

Podpora bzip2 není v PHP implicitně k dispozici. K aktivaci budete muset při kompilaci PHP použít konfigurační volbu --with-bz2. Tento modul vyžaduje bzip2/libbzip2 verze >= 1.0.x.

Konfigurace běhu

Toto rozšíření nemá definováno žádné konfigurační direktivy.

Typy prostředků

Toto rozšíření definuje jeden typ prostředku: souborový ukazatel identifikující soubor bz2, nad kterým se pracuje.

Předdefinované konstanty

Toto rozšíření nemá definovány žádné konstanty.

Příklady

Tento příklad otevře dočasný soubor a zapíše do něj testovací řetezec; potom vypíše obsah souboru.

Příklad 1. Malý příklad na bzip2

<?php

$filename = "/tmp/testfile.bz2";
$str = "Toto je testovací řetězec.\n";

// otevři soubor pro zápis
$bz = bzopen($filename, "w");

// zapoš řetězec do souboru
bzwrite($bz, $str);

// zavři soubor
bzclose($bz);

// otevři soubor pro čtení
$bz = bzopen($filename, "r");

// přečti 10 znaků
print bzread($bz, 10);

// tiskni dokud není konec souboru (nebo následující 1024. znak) a zavři soubor  
print bzread($bz);

bzclose($bz);

?>

Obsah
bzclose -- Zavře ukazatel na soubor bzip2
bzcompress -- Zkomprimuje řetězec algoritmem bzip2
bzdecompress -- Dekomprimuje data komprimovaná pomocí bzip2
bzerrno -- Returns a bzip2 error number
bzerror -- Returns the bzip2 error number and error string in an array
bzerrstr -- Returns a bzip2 error string
bzflush -- Force a write of all buffered data
bzopen -- Open a bzip2 compressed file
bzread -- Binary safe bzip2 file read
bzwrite -- Binary safe bzip2 file write

bzclose

(PHP 4 >= 4.0.4)

bzclose -- Zavře ukazatel na soubor bzip2

Popis

int bzclose ( resource bz)

Zavře soubor bzip2 odkazovaný ukazatelem bz.

Vrací TRUE při úspěchu, FALSE při selhání.

Ukazatel na soubor musí být platný a musí ukazovat na soubor úspěšně otevřený pomocí bzopen().

Viz také bzopen().

bzcompress

(PHP 4 >= 4.0.4)

bzcompress -- Zkomprimuje řetězec algoritmem bzip2

Popis

string bzcompress ( string source [, int blocksize [, int workfactor]])

bzcompress() komprimuje řetězec source a vrací ho ve formě dat získaných pomocí algoritmu bzip2.

Nepovinný parametr blocksize specifikuje velikost bloku použitou při komprimaci; mělo by to být číslo od 1 do 9, kde 9 znamená nejúčinnější kompresi, ale s většími nároky na potřebné prostředky. Implicitní hodnota blocksize je 4.

Nepovinný parametr workfactor určuje, jak se kompresní mechanismus chová v případě nejhorších, velmi se opakujících, vstupnách dat. Může nabývat hodnot mezi 0 a 250; 0 představuje speciální případ, 30 je implicitní hodnota. Generovaný výstup je bez ohledu na workfactor vždy stejný.

Příklad 1. bzcompress() Příklad

<?php $str = "zkušební data"; $bzstr = bzcompress($str, 9); print( $bzstr ); ?>

Viz také bzdecompress().

bzdecompress

(PHP 4 >= 4.0.4)

bzdecompress -- Dekomprimuje data komprimovaná pomocí bzip2

Popis

string bzdecompress ( string source [, int small])

bzdecompress() dekomprimuje řetězec source obsahující data komprimovaná pomocí algoritmu bzip2, a vrací je. Pokud má nepovinný parametr small hodnotu TRUE, použije se alternativní dekompresní algoritmus s nižšími nároky na paměť (maximální pamětové požadavky klesnou na cca 2300 KB), ale zhruba poloviční rychlostí. Více informací najdete v dokumentaci k bzip2.

Příklad 1. bzdecompress()

<?php $start_str = "Tohle není upřímný obličej?"; $bzstr = bzcompress($start_str); print( "Komprimovaný řetězec: " ); print( $bzstr ); print( "\n<br>\n" ); $str = bzdecompress($bzstr); print( "Dekomprimovaný řetezec: " ); print( $str ); print( "\n<br>\n" ); ?>

Viz také bzcompress().

bzerrno

(PHP 4 >= 4.0.4)

bzerrno -- Returns a bzip2 error number

Description

int bzerrno ( resource bz)

Returns the error number of any bzip2 error returned by the file pointer bz.

See also bzerror() and bzerrstr().

bzerror

(PHP 4 >= 4.0.4)

bzerror -- Returns the bzip2 error number and error string in an array

Description

array bzerror ( resource bz)

Returns the error number and error string, in an associative array, of any bzip2 error returned by the file pointer bz.

Příklad 1. bzerror() Example

<?php $error = bzerror($bz); echo $error["errno"]; echo $error["errstr"]; ?>

See also bzerrno() and bzerrstr().

bzerrstr

(PHP 4 >= 4.0.4)

bzerrstr -- Returns a bzip2 error string

int bzwrite ( resource bz, string data [, int length])

bzwrite() writes the contents of the string data to the bzip2 file stream pointed to by bz. If the optional length argument is given, writing will stop after length (uncompressed) bytes have been written or the end of string is reached, whichever comes first.

Příklad 1. bzwrite() Example

<?php $str = "uncompressed data"; $bz = bzopen("/tmp/foo.bz2", "w"); bzwrite($bz, $str, strlen($str)); bzclose($bz); ?>

VI. Kalendářové funkce

Kalendářové funkce jsou přístupné pouze pokud máte zkompilovanout calendar extenzi umístěnou v adresáři "dl" or "ext" ve zdrojovém kódu PHP. Před jejím použitím si prosím přečtěte README soubor.

Calendar extenze představuje sadu funkcí určených ke zjednodušení převodů mezi různými kalendáři. Prostředníkem nebo standardem, na kterém je založena je Julian Day Count. To je počet dní začínající daleko před jakýmkoli datem o které by se většina lidí zajímala (někde kolem 4000 př. n. l.). Pokud chcete převádět mezi kalendářovými systémy, musíte nejdřív převést na Julian Day Count, potom na kýžený kalendář. Julian Day Count se velmi liší od Juliánského kaledáře! Více informací o kalendářových systémech viz http://genealogy.org/~scottlee/cal-overview.html. Tyto instrukce obsahují výňatky z této stránky (v uvozovkách).

Obsah
cal_days_in_month -- Return the number of days in a month for a given year and calendar
cal_from_jd -- Converts from Julian Day Count to a supported calendar and return extended information
cal_info -- Returns information about a particular calendar
cal_to_jd -- Converts from a supported calendar to Julian Day Count
easter_date -- Zjistit UNIXový timestamp Velikonoční půlnoci v daném roce
easter_days -- Get number of days after March 21 on which Easter falls for a given year
FrenchToJD -- Převést datum z Francouzského republikánského kalendáře na Julian Day Count
GregorianToJD -- Převést Gregoriánské datum na Julian Day Count
JDDayOfWeek -- Vrátit den v týdnu
JDMonthName -- Vrátit název měsíce
JDToFrench -- Převést Julian Day Count na Francouzský republikánský kalendář
JDToGregorian -- Převést Julian Day Count na Gregoriánské datum
JDToJewish -- Převést Julian Day Count na idovský kalendář
JDToJulian -- Převést Julian Day Count na Juliánské datum
jdtounix -- Převést Julian Day Count na UNIXový timestamp
JewishToJD -- Převést datum podle idovského kalendáře na Julian Day Count
JulianToJD -- Převést Juliánské datum na Julian Day Count
unixtojd -- Převést UNIXový timestamp na Julian Day Count

cal_days_in_month

(PHP 4 >= 4.1.0)

cal_days_in_month -- Return the number of days in a month for a given year and calendar

Description

int cal_days_in_month ( int calendar, int month, int year)

This function will return the number of days in the month of year for the specified calendar.

cal_from_jd

(PHP 4 >= 4.1.0)

cal_from_jd -- Converts from Julian Day Count to a supported calendar and return extended information

Description

array cal_from_jd ( int jd, int calendar)

cal_info

(PHP 4 >= 4.1.0)

cal_info -- Returns information about a particular calendar

Description

array cal_info ( int calendar)

cal_to_jd

(PHP 4 >= 4.1.0)

cal_to_jd -- Converts from a supported calendar to Julian Day Count

Description

int cal_to_jd ( int calendar, int month, int day, int year)

easter_date

(PHP 3>= 3.0.9, PHP 4 )

easter_date -- Zjistit UNIXový timestamp Velikonoční půlnoci v daném roce

Popis

int easter_date ( int year)

Vrací UNIXový timestamp odpovídající Velikonoční půlnoci v daném roce. Default year je současný rok.

Varování: Tato funkce vygeneruje varování, pokud je year mimo rozsah UNIXových timestampů (tj. před 1970 nebo po 2037).

Příklad 1. Ukázka easter_date()

echo date ("M-d-Y", easter_date(1999)); /* "Apr-04-1999" */ echo date ("M-d-Y", easter_date(2000)); /* "Apr-23-2000" */ echo date ("M-d-Y", easter_date(2001)); /* "Apr-15-2001" */

Datum Velikonoc bylo definováno Nicaejským koncilem v r. 325 n. l. jako neděle po prvním úplňku který připadá na nebo po jarní rovnodennosti. Rovnodennost se vždy předpokládá na 21. března, takže se výpočet redukuje na určení data úplňku a data následující neděle. Zde použitý algoritmus byl poprvé použit kolem roku 532 Dionysiem Exiguem. V Juliánském kalendáři (pro léta před 1753) se na sledování fází Měsíce používal jednoduchý devatenáctiletý cyklus. V Gregoriánském kalendáři (pro léta po 1753 - navržen Claviem a Liliem a zaveden papežem Řehořem XIII v říjnu 1582, v Británii a jejích koloniích v září 1752) se přidávají dva faktory, které tento cyklus zpřesňují.

(Kód je založen na C programu od Simona Kershawa, <webmaster@ely.anglican.org>)

Výpočet Velikonoc před rokem 1970 nebo po roce 2037 viz easter_days().

easter_days

(PHP 3>= 3.0.9, PHP 4 )

easter_days -- Get number of days after March 21 on which Easter falls for a given year

Popis

int easter_days ( int year)

Vrací počet dní od 21. března do Velikonoc v daném roce. Default year je současný rok.

mixed jddayofweek ( int julianday, int mode)

Vrací den v týdnu. V závislosti na módu vrací řetězec nebo integer.

Tabulka 1. Kalendářové týdenní módy

Mód	Význam
0	Vrací číslo dne jako integer (0=sunday, 1=monday, etc)
1	Vrací řetězec obsahující název dne v týdnu (anglický gregoriánský)
2	Vrací řetězec obsahující zkrácený název dne v týdnu (anglický gregoriánský)

JDMonthName

(PHP 3, PHP 4 )

JDMonthName -- Vrátit název měsíce

Popis

string jdmonthname ( int julianday, int mode)

Vrací řetězec obsahující název měsíce. mode určuje, na který kalendář se má Julian Day Count konvertovat a jaký typ jména se má vrátit.

Tabulka 1. Kalendářové módy

Mód	Význam
0	Gregoriánský - zkrácený
1	Gregoriánský
2	Juliánský - zkrácený
3	Juliánský
4	idovský
5	Francouzský republikánský

Viz také: jdtounix().

Poznámka: Tato funkce byla přidána v PHP 4 RC2.

Poznámka: Tato funkce byla přidána v PHP 4 RC2.

VII. CCVS API Funkce

Tyto funkce představují interface k CCVS API, a umožnují tak přímo pracovat s CCVS z vašich PHP skriptů. CCVS je RedHatí řešení "zprostředkovatele" ve zpracování kreditních karet. Umož%nuje vám oslovovat přímo zpracovatele kreditních karet přes váš *nix systém a modem. Pomocí CCVS modulu pro PHP můžete zpracovávat kreditní karty přes CCVS ve vašich PHP skriptech. Následující reference tento proces přiblíží.

Pokud chcete zapnout CCVS podporu v PHP, zjistěte si nejdříve instalační adresář CCVS. Potom budete muset PHP zkonfigurovat s --with-ccvs. Pokud toto použijete be udání cesty k vaší instalaci CCVS, PHP se pokusí podívat do defaultní instalační lokace CCVS (/usr/local/ccvs). Pokud je CCVS na nestandardním místě, spustěte configure s: --with-ccvs=$ccvs_path, kde $ccvs_path je cesta k vaší instalaci CVS. Pozn.: Podpora CCVS vyžaduje existenci $ccvs_path/lib a $ccvs_path/include, a přítomnost cv_api.h v adresáři include a libccvs.a v adresáři lib.

Dále je potřeba, aby běžel proces ccvsd. Navíc, PHP processy musí běhat pod stejným uživatelem, pod kterým běhá CCVS (např. pokud jste instalovali ccvs jako 'ccvs', vaše PHP procesy musí také běhat jako 'ccvs').

Další informace o CCVS jsou na http://www.redhat.com/products/ccvs.

Na této sekci dokumentace se pracuje. Prozatím RedHat udržuje mírně zastaralou, ale stále užitečnou dokumentaci na http://www.redhat.com/products/ccvs/support/CCVS3.3docs/ProgPHP.html.

Obsah
ccvs_add -- Add data to a transaction
ccvs_auth -- Perform credit authorization test on a transaction
ccvs_command -- Performs a command which is peculiar to a single protocol, and thus is not available in the general CCVS API
ccvs_count -- Find out how many transactions of a given type are stored in the system
ccvs_delete -- Delete a transaction
ccvs_done -- Terminate CCVS engine and do cleanup work
ccvs_init -- Initialize CCVS for use
ccvs_lookup -- Look up an item of a particular type in the database #
ccvs_new -- Create a new, blank transaction
ccvs_report -- Return the status of the background communication process
ccvs_return -- Transfer funds from the merchant to the credit card holder
ccvs_reverse -- Perform a full reversal on an already-processed authorization
ccvs_sale -- Transfer funds from the credit card holder to the merchant
ccvs_status -- Check the status of an invoice
ccvs_textvalue -- Get text return value for previous function call
ccvs_void -- Perform a full reversal on a completed transaction

VIII. Funkce na podporu COM ve Windows

Tyto funkce jsou dostupné pouze ve Windows verzi PHP. Byly přidány v PHP 4.

Obsah
COM -- COM class
VARIANT -- VARIANT class
com_addref -- Increases the components reference counter.
com_get -- Získává hodnotu vlastnosti COM komponenty
com_invoke -- Volá metodu COM komponenty.
com_isenum -- Grabs an IEnumVariant
com_load_typelib -- Loads a Typelib
com_load -- Vytvoří nový odkaz na COM komponentu
com_propget -- Získává hodnotu vlastnosti COM komponenty
com_propput -- Přiřazuje hodnotu vlastnosti COM komponenty.
com_propset -- Přiřazuje hodnotu vlastnosti COM komponenty.
com_release -- Decreases the components reference counter.
com_set -- Přiřazuje hodnotu vlastnosti COM komponenty.

COM

(unknown)

COM -- COM class

Přehled

$obj = new COM("server.object")

Description

The COM class provides a framework to integrate (D)COM components into your php scripts.

Methods

string COM::COM ( string module_name [, string server_name [, int codepage]])

COM class constructor. Parameters:

module_name: name or class-id of the requested component.
server_name: name of the DCOM server from which the component should be fetched. If NULL, localhost is assumed. To allow DCOM com.allow_dcom has to be set to TRUE in php.ini.
codepage: specifies the codepage that is used to convert php-strings to unicode-strings and vice versa. Possible values are CP_ACP, CP_MACCP, CP_OEMCP, CP_SYMBOL, CP_THREAD_ACP, CP_UTF7 and CP_UTF8.

Příklad 1. COM example (1)

// starting word $word = new COM("word.application") or die("Unable to instanciate Word"); print "Loaded Word, version {$word->Version}\n"; //bring it to front $word->Visible = 1; //open an empty document $word->Documents->Add(); //do some weird stuff $word->Selection->TypeText("This is a test..."); $word->Documents[1]->SaveAs("Useless test.doc"); //closing word $word->Quit(); //free the object $word->Release(); $word = null;

Příklad 2. COM example (2)

$conn = new COM("ADODB.Connection") or die("Cannot start ADO"); $conn->Open("Provider=SQLOLEDB; Data Source=localhost; Initial Catalog=database; User ID=user; Password=password"); $rs = $conn->Execute("SELECT * FROM sometable"); // Recordset $num_columns = $rs->Fields->Count(); echo $num_columns . "\n"; for ($i=0; $i < $num_columns; $i++) { $fld[$i] = $rs->Fields($i); } $rowcount = 0; while (!$rs->EOF) { for ($i=0; $i < $num_columns; $i++) { echo $fld[$i]->value . "\t"; } echo "\n"; $rowcount++; // increments rowcount $rs->MoveNext(); } $rs->Close(); $conn->Close(); $rs->Release(); $conn->Release(); $rs = null; $conn = null;

VARIANT

(unknown)

VARIANT -- VARIANT class

Přehled

$vVar = new VARIANT($var)

Description

A simple container to wrap variables into VARIANT structures.

Methods

string VARIANT::VARIANT ( [mixed value [, int type [, int codepage]]])

VARIANT class constructor. Parameters:

value: initial value. if omitted an VT_EMPTY object is created.
type: specifies the content type of the VARIANT object. Possible values are VT_UI1, VT_UI2, VT_UI4, VT_I1, VT_I2, VT_I4, VT_R4, VT_R8, VT_INT, VT_UINT, VT_BOOL, VT_ERROR, VT_CY, VT_DATE, VT_BSTR, VT_DECIMAL, VT_UNKNOWN, VT_DISPATCH and VT_VARIANT. These values are mutual exclusive, but they can be combined with VT_BYREF to specify being a value. If omitted, the type of value is used. Consult the msdn library for additional information.
codepage: specifies the codepage that is used to convert php-strings to unicode-strings and vice versa. Possible values are CP_ACP, CP_MACCP, CP_OEMCP, CP_SYMBOL, CP_THREAD_ACP, CP_UTF7 and CP_UTF8.

com_addref

(PHP 4 >= 4.1.0)

com_addref -- Increases the components reference counter.

Description

void com_addref ( void)

Increases the components reference counter.

com_get

(PHP 3>= 3.0.3, PHP 4 >= 4.0.5)

com_get -- Získává hodnotu vlastnosti COM komponenty

Popis

mixed com_get ( resource com_object, string property)

Vrací hodnotu property COM komponenty odkazované com_object. Při chybě vrací FALSE.

com_invoke

(PHP 3>= 3.0.3)

com_invoke -- Volá metodu COM komponenty.

Popis

mixed com_invoke ( resource com_object, string function_name [, mixed parametry funkce, ...])

com_invoke() volá metodu COM komponenty odkazované com_object. Pokud dojde k chybě, vrací FALSE, při úspěchu vrací návratovou hodnotu metody function_name.

com_isenum

(PHP 4 >= 4.1.0)

com_isenum -- Grabs an IEnumVariant

Description

void com_isenum ( object com_module)

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

com_load_typelib

(PHP 4 >= 4.1.0)

com_load_typelib -- Loads a Typelib

Description

Popis

void com_set ( resource com_object, string property, mixed value)

Nastavuje hodnotu vlastnosti property COM komponent odkazované com_object. Vrací TRUE, pokud je property nastaveno. Při chybě vrací FALSE.

IX. Funkce pro práci s třídami/objekty

Úvod

About

Tyto funkce vám umožňují získávat informace o třídách a instancích. Můžete zjistit název třídy do které objekt patří nebo jeho proměnné a metody. Pomocí těchto funkcí můžete zjistit nejen příslušnost objektu k třídě, ale i jeho předka (tj. kterou třídu třída tohoto objektu rozšiřuje).

Ukázka použití

V této ukázce nejdříve definujeme základní třídu a rozšíření této třídy. Základní třída popisuje obecnou zeleninu, ať už je jedlá nebo ne a bez ohledu na její barvu. Podtřída Spenat přidává metodu na uvaření této zeleniny a další, která zjistí, jestli je vařená.

Příklad 1. classes.inc

<?php // základní třída s členskými proměnnými a metodami class Zelenina { var $jedla; var $barva; function Zelenina( $jedla, $barva="green" ) { $this->jedla = $jedla; $this->barva = $barva; } function je_jedla() { return $this->jedla; } function jaka_barva() { return $this->barva; } } // konec tridy zelenina // rozsiruje zakladni tridu class Spenat extends Zelenina { var $varena = false; function Spenat() { $this->Zelenina( true, "zelena" ); } function cook_it() { $this->varena = true; } function je_varena() { return $this->varena; } } // konec tridy Spenat ?>

Potom z těchto tříd vytvoříme 2 objekty a vytiskneme informace o nich, vč. rodičovských tříd. Také definujeme některé pomocné funkce, především kvůli pohodlnému tisku informací.

Příklad 2. test_script.php

<pre> <?php include "classes.inc"; // pomocné funkce function vytiskni_promenne($obj) { $pole = get_object_vars($obj); while (list($vlastnost, $hodnota) = each($pole)) echo "\t$vlastnost = $hodnota\n"; } function vytiskni_metody($obj) { $pole = get_class_methods(get_class($obj)); foreach ($pole as $metoda) echo "\tfunction $metoda()\n"; } function class_parentage($obj, $class) { global $$obj; if (is_subclass_of($$obj, $class)) { echo "Objekt $obj patri do tridy ".get_class($$obj); echo " ktera je podtridou $class\n"; } else { echo "Objekt $obj nepatri do podtridy tridy $class\n"; } } // instancujeme 2 objekty $zeleninka = new Zelenina(true,"modra"); $listnaty = new Spenat(); // vytisknout informace o obou objektech echo "zeleninka: CLASS ".get_class($zeleninka)."\n"; echo "listnaty: CLASS ".get_class($listnaty); echo ", PARENT ".get_parent_class($listnaty)."\n"; // vytisknout vlastnosti zeleninky echo "\nzeleninka: Vlastnosti\n"; print_vars($zeleninka); // a metody objektu listnaty echo "\nlistnaty: Metody\n"; print_methods($listnaty); echo "\nRodic:\n"; class_parentage("listnaty", "Spenat"); class_parentage("listnaty", "Zelenina"); ?> </pre>

Je třeba poznamenat, že ve výše uvedené ukázce je objekt $listnaty instancí třídy Spenat, která je podtřídou třídy Zelenina, a poslední část výše uvedeného skriptu tudíž vytiskne:

[...]
Rodic:
Objekt listnaty nepatri do podtridy tridy Spenat
Object listnaty patri do tridy Spenat, ktera je podtridou tridy Zelenina

Obsah
call_user_method_array -- Call a user method given with an array of parameters [deprecated]
call_user_method -- Zavolat uživatelsky definouvanou metodu určitého objektu
class_exists -- Zjistit, jestli je třída definována
get_class_methods -- Vrátit pole názvů metod třídy
get_class_vars -- Vrátit pole defaultních vlastností třídy
get_class -- Vrátit jméno třídy objektu
get_declared_classes -- Vrátit pole názvů definovaných tříd
get_object_vars -- Vrátit asociativní pole vlastností objektu
get_parent_class -- Vrátit název rodičovské třídy objektu
is_a -- Returns TRUE if the object is of this class or has this class as one of its parents
is_subclass_of -- Zjistit, jestli objekt patří do podtřídy určité třídy
method_exists -- Zjistit, jestli má třída určitou metodu

call_user_method_array

(PHP 4 >= 4.0.5)

call_user_method_array -- Call a user method given with an array of parameters [deprecated]

Description

mixed call_user_method_array ( string method_name, object obj [, array paramarr])

Varování

The call_user_method_array() function is deprecated as of PHP 4.1.0, use the call_user_func_array() variety with the array(&$obj, "method_name") syntax instead.

Calls the method referred by method_name from the user defined obj object, using the parameters in paramarr.

Poznámka: This function was added to the CVS code after release of PHP 4.0.4pl1

call_user_method

(PHP 3>= 3.0.3, PHP 4 )

call_user_method -- Zavolat uživatelsky definouvanou metodu určitého objektu

Popis

mixed call_user_method ( string method_name, object obj [, mixed parameter [, mixed ...]])

Zavolá metodu method_name objektu obj. Ukázka využití je níže, kde definujeme třídu, vytvoříme objekt a použijeme call_user_method() k nepřímému volání její print_info metody.

<?php
class Country {
    var $NAME;
    var $TLD;

    function Country($name, $tld) {
        $this->NAME = $name;
        $this->TLD = $tld;
    }

    function print_info($prestr="") {
        echo $prestr."Country: ".$this->NAME."\n";
        echo $prestr."Top Level Domain: ".$this->TLD."\n";
    }
}

$cntry = new Country("Peru","pe");

echo "* Calling the object method directly\n";
$cntry->print_info();

echo "\n* Calling the same method indirectly\n";
call_user_method ("print_info", $cntry, "\t");
?>

Viz také call_user_func().

class_exists

(PHP 4 )

class_exists -- Zjistit, jestli je třída definována

Popis

This function returns TRUE if the object is of this class or has this class as one of its parents, FALSE otherwise.

is_subclass_of

(PHP 4 )

is_subclass_of -- Zjistit, jestli objekt patří do podtřídy určité třídy

Popis

bool is_subclass_of ( object obj, string superclass)

Tato funkce vrací TRUE, pokud je objekt obj instancí třídy, která je podtřídou superclass, jinak FALSE.

Viz také get_class(), get_parent_class()

method_exists

(PHP 4 )

method_exists -- Zjistit, jestli má třída určitou metodu

Popis

bool method_exists ( object object, string method_name)

Tato funkce vrací TRUE, pokud má object definovánu metodu method_name, jinak FALSE.

X. ClibPDF functions

Úvod

ClibPDF lets you create PDF documents with PHP. It is available for download from FastIO, but requires that you purchase a license for commercial use. ClibPDF functionality and API are similar to PDFlib.

This documentation should be read alongside the ClibPDF manual since it explains the library in much greater detail.

Many functions in the native ClibPDF and the PHP module, as well as in PDFlib, have the same name. All functions except for cpdf_open() take the handle for the document as their first parameter.

Currently this handle is not used internally since ClibPDF does not support the creation of several PDF documents at the same time. Actually, you should not even try it, the results are unpredictable. I can't oversee what the consequences in a multi threaded environment are. According to the author of ClibPDF this will change in one of the next releases (current version when this was written is 1.10). If you need this functionality use the pdflib module.

A nice feature of ClibPDF (and PDFlib) is the ability to create the pdf document completely in memory without using temporary files. It also provides the ability to pass coordinates in a predefined unit length. (This feature can also be simulated by pdf_translate() when using the PDFlib functions.)

Another nice feature of ClibPDF is the fact that any page can be modified at any time even if a new page has been already opened. The function cpdf_set_current_page() allows to leave the current page and presume modifying an other page.

Most of the functions are fairly easy to use. The most difficult part is probably creating a very simple PDF document at all. The following example should help you to get started. It creates a document with one page. The page contains the text "Times-Roman" in an outlined 30pt font. The text is underlined.

Předdefinované konstanty

Tyto konstanty jsou definovány tímto rozšířením a budou k dispozici pouze tehdy, bylo-li rozšíření zkompilováno společně s PHP nebo dynamicky zavedeno za běhu.

CPDF_PM_NONE (integer)
CPDF_PM_OUTLINES (integer)
CPDF_PM_THUMBS (integer)
CPDF_PM_FULLSCREEN (integer)
CPDF_PL_SINGLE (integer)
CPDF_PL_1COLUMN (integer)
CPDF_PL_2LCOLUMN (integer)
CPDF_PL_2RCOLUMN (integer)

Příklady

Příklad 1. Simple ClibPDF Example

<?php
$cpdf = cpdf_open(0);
cpdf_page_init($cpdf, 1, 0, 595, 842, 1.0);
cpdf_add_outline($cpdf, 0, 0, 0, 1, "Page 1");
cpdf_begin_text($cpdf);
cpdf_set_font($cpdf, "Times-Roman", 30, "WinAnsiEncoding");
cpdf_set_text_rendering($cpdf, 1);
cpdf_text($cpdf, "Times Roman outlined", 50, 750);
cpdf_end_text($cpdf);
cpdf_moveto($cpdf, 50, 740);
cpdf_lineto($cpdf, 330, 740);
cpdf_stroke($cpdf);
cpdf_finalize($cpdf);
Header("Content-type: application/pdf");
cpdf_output_buffer($cpdf);
cpdf_close($cpdf);
?>

The pdflib distribution contains a more complex example which creates a series of pages with an analog clock. Here is that example converted into PHP using the ClibPDF extension:

Příklad 2. pdfclock example from pdflib 2.0 distribution

<?php
$radius = 200;
$margin = 20;
$pagecount = 40;

$pdf = cpdf_open(0);
cpdf_set_creator($pdf, "pdf_clock.php3");
cpdf_set_title($pdf, "Analog Clock");
  
while($pagecount-- > 0) {
  cpdf_page_init($pdf, $pagecount+1, 0, 2 * ($radius + $margin), 2 * ($radius + $margin), 1.0);
  
  cpdf_set_page_animation($pdf, 4, 0.5, 0, 0, 0);  /* wipe */
  
  cpdf_translate($pdf, $radius + $margin, $radius + $margin);
  cpdf_save($pdf);
  cpdf_setrgbcolor($pdf, 0.0, 0.0, 1.0);
  
  /* minute strokes */
  cpdf_setlinewidth($pdf, 2.0);
  for ($alpha = 0; $alpha < 360; $alpha += 6)
    {
    cpdf_rotate($pdf, 6.0);
    cpdf_moveto($pdf, $radius, 0.0);
    cpdf_lineto($pdf, $radius-$margin/3, 0.0);
    cpdf_stroke($pdf);
    }
  
  cpdf_restore($pdf);
  cpdf_save($pdf);
 
  /* 5 minute strokes */
  cpdf_setlinewidth($pdf, 3.0);
  for ($alpha = 0; $alpha < 360; $alpha += 30)
  {
    cpdf_rotate($pdf, 30.0);
    cpdf_moveto($pdf, $radius, 0.0);
    cpdf_lineto($pdf, $radius-$margin, 0.0);
    cpdf_stroke($pdf);
  }

  $ltime = getdate();

  /* draw hour hand */
  cpdf_save($pdf);
  cpdf_rotate($pdf, -(($ltime['minutes']/60.0) + $ltime['hours'] - 3.0) * 30.0);
  cpdf_moveto($pdf, -$radius/10, -$radius/20);
  cpdf_lineto($pdf, $radius/2, 0.0);
  cpdf_lineto($pdf, -$radius/10, $radius/20);
  cpdf_closepath($pdf);
  cpdf_fill($pdf);
  cpdf_restore($pdf);

  /* draw minute hand */
  cpdf_save($pdf);
  cpdf_rotate($pdf, -(($ltime['seconds']/60.0) + $ltime['minutes'] - 15.0) * 6.0);
  cpdf_moveto($pdf, -$radius/10, -$radius/20);
  cpdf_lineto($pdf, $radius * 0.8, 0.0);
  cpdf_lineto($pdf, -$radius/10, $radius/20);
  cpdf_closepath($pdf);
  cpdf_fill($pdf);
  cpdf_restore($pdf);

  /* draw second hand */
  cpdf_setrgbcolor($pdf, 1.0, 0.0, 0.0);
  cpdf_setlinewidth($pdf, 2);
  cpdf_save($pdf);
  cpdf_rotate($pdf, -(($ltime['seconds'] - 15.0) * 6.0));
  cpdf_moveto($pdf, -$radius/5, 0.0);
  cpdf_lineto($pdf, $radius, 0.0);
  cpdf_stroke($pdf);
  cpdf_restore($pdf);

  /* draw little circle at center */
  cpdf_circle($pdf, 0, 0, $radius/30);
  cpdf_fill($pdf);

  cpdf_restore($pdf);

  cpdf_finalize_page($pdf, $pagecount+1);
}

cpdf_finalize($pdf);
Header("Content-type: application/pdf");
cpdf_output_buffer($pdf);
cpdf_close($pdf);
?>

Viz také

See also the PDFlib extension documentation.

Obsah
cpdf_add_annotation -- Adds annotation
cpdf_add_outline -- Adds bookmark for current page
cpdf_arc -- Draws an arc
cpdf_begin_text -- Starts text section
cpdf_circle -- Draw a circle
cpdf_clip -- Clips to current path
cpdf_close -- Closes the pdf document
cpdf_closepath_fill_stroke -- Close, fill and stroke current path
cpdf_closepath_stroke -- Close path and draw line along path
cpdf_closepath -- Close path
cpdf_continue_text -- Output text in next line
cpdf_curveto -- Draws a curve
cpdf_end_text -- Ends text section
cpdf_fill_stroke -- Fill and stroke current path
cpdf_fill -- Fill current path
cpdf_finalize_page -- Ends page
cpdf_finalize -- Ends document
cpdf_global_set_document_limits -- Sets document limits for any pdf document
cpdf_import_jpeg -- Opens a JPEG image
cpdf_lineto -- Draws a line
cpdf_moveto -- Sets current point
cpdf_newpath -- Starts a new path
cpdf_open -- Opens a new pdf document
cpdf_output_buffer -- Outputs the pdf document in memory buffer
cpdf_page_init -- Starts new page
cpdf_place_inline_image -- Places an image on the page
cpdf_rect -- Draw a rectangle
cpdf_restore -- Restores formerly saved environment
cpdf_rlineto -- Draws a line
cpdf_rmoveto -- Sets current point
cpdf_rotate_text -- Sets text rotation angle
cpdf_rotate -- Sets rotation
cpdf_save_to_file -- Writes the pdf document into a file
cpdf_save -- Saves current environment
cpdf_scale -- Sets scaling
cpdf_set_action_url -- Sets hyperlink
cpdf_set_char_spacing -- Sets character spacing
cpdf_set_creator -- Sets the creator field in the pdf document
cpdf_set_current_page -- Sets current page
cpdf_set_font_directories -- Sets directories to search when using external fonts
cpdf_set_font_map_file -- Sets fontname to filename translation map when using external fonts
cpdf_set_font -- Select the current font face and size
cpdf_set_horiz_scaling -- Sets horizontal scaling of text
cpdf_set_keywords -- Sets the keywords field of the pdf document
cpdf_set_leading -- Sets distance between text lines
cpdf_set_page_animation -- Sets duration between pages
cpdf_set_subject -- Sets the subject field of the pdf document
cpdf_set_text_matrix -- Sets the text matrix
cpdf_set_text_pos -- Sets text position
cpdf_set_text_rendering -- Determines how text is rendered
cpdf_set_text_rise -- Sets the text rise
cpdf_set_title -- Sets the title field of the pdf document
cpdf_set_viewer_preferences -- How to show the document in the viewer
cpdf_set_word_spacing -- Sets spacing between words
cpdf_setdash -- Sets dash pattern
cpdf_setflat -- Sets flatness
cpdf_setgray_fill -- Sets filling color to gray value
cpdf_setgray_stroke -- Sets drawing color to gray value
cpdf_setgray -- Sets drawing and filling color to gray value
cpdf_setlinecap -- Sets linecap parameter
cpdf_setlinejoin -- Sets linejoin parameter
cpdf_setlinewidth -- Sets line width
cpdf_setmiterlimit -- Sets miter limit
cpdf_setrgbcolor_fill -- Sets filling color to rgb color value
cpdf_setrgbcolor_stroke -- Sets drawing color to rgb color value
cpdf_setrgbcolor -- Sets drawing and filling color to rgb color value
cpdf_show_xy -- Output text at position
cpdf_show -- Output text at current position
cpdf_stringwidth -- Returns width of text in current font
cpdf_stroke -- Draw line along path
cpdf_text -- Output text with parameters
cpdf_translate -- Sets origin of coordinate system

Poznámka: The return value will be needed in further versions of ClibPDF as the first parameter in all other functions which are writing to the pdf document.

The ClibPDF library takes the filename "-" as a synonym for stdout. If PHP is compiled as an apache module this will not work because the way ClibPDF outputs to stdout does not work with apache. You can solve this problem by skipping the filename and using cpdf_output_buffer() to output the pdf document.

Description

void cpdf_rotate_text ( int pdfdoc, float angle)

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

cpdf_rotate

(PHP 3>= 3.0.8, PHP 4 )

cpdf_rotate -- Sets rotation

Description

void cpdf_rotate ( int pdf document, float angle)

The cpdf_rotate() function set the rotation in degrees to angle.

cpdf_save_to_file

(PHP 3>= 3.0.8, PHP 4 )

cpdf_save_to_file -- Writes the pdf document into a file

Description

void cpdf_save_to_file ( int pdf document, string filename)

void cpdf_set_action_url ( int pdfdoc, float xll, float yll, float xur, float xur, string url [, int mode])

void cpdf_set_font_directories ( int pdfdoc, string pfmdir, string pfbdir)

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

cpdf_set_font_map_file

(PHP 4 >= 4.0.6)

cpdf_set_font_map_file -- Sets fontname to filename translation map when using external fonts

Description

void cpdf_set_font_map_file ( int pdfdoc, string filename)

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

cpdf_set_font

(PHP 3>= 3.0.8, PHP 4 )

cpdf_set_font -- Select the current font face and size

Description

void cpdf_set_font ( int pdf document, string font name, float size, string encoding)

The cpdf_set_font() function sets the current font face, font size and encoding. Currently only the standard postscript fonts are supported.

void cpdf_set_page_animation ( int pdf document, int transition, float duration)

The cpdf_set_page_animation() function set the transition between following pages.

The value of transition can be

0 for none,

1 for two lines sweeping across the screen reveal the page,

2 for multiple lines sweeping across the screen reveal the page,

3 for a box reveals the page,

4 for a single line sweeping across the screen reveals the page,

5 for the old page dissolves to reveal the page,

6 for the dissolve effect moves from one screen edge to another,

void cpdf_set_text_rendering ( int pdf document, int mode)

void cpdf_show_xy ( int pdf document, string text, float x-coor, float y-coor [, int mode])

The cpdf_show_xy() function outputs the string text at position with coordinates (x-coor, y-coor).

Poznámka: The function cpdf_show_xy() is identical to cpdf_text() without the optional parameters.

The optional parameter mode determines the unit length. If it's 0 or omitted the default unit as specified for the page is used. Otherwise the coordinates are measured in postscript points disregarding the current unit. The optional parameter orientation is the rotation of the text in degree. The optional parameter alignmode determines how the text is aligned.

See the ClibPDF documentation for possible values.

cpdf_translate

(PHP 3>= 3.0.8, PHP 4 )

cpdf_translate -- Sets origin of coordinate system

Description

void cpdf_translate ( int pdf document, float x-coor, float y-coor [, int mode])

The cpdf_translate() function set the origin of coordinate system to the point (x-coor, y-coor).

XI. Crack functions

Úvod

These functions allow you to use the CrackLib library to test the 'strength' of a password. The 'strength' of a password is tested by that checks length, use of upper and lower case and checked against the specified CrackLib dictionary. CrackLib will also give helpful diagnostic messages that will help 'strengthen' the password.

Požadavky

More information regarding CrackLib along with the library can be found at http://www.users.dircon.co.uk/~crypto/.

Instalace

In order to use these functions, you must compile PHP with Crack support by using the --with-crack[=DIR] option.

Konfigurace běhu

Toto rozšíření nemá definováno žádné konfigurační direktivy.

Typy prostředků

Toto rezšíření nemá definován žádný typ prostředku (resource).

Předdefinované konstanty

Toto rozšíření nemá definovány žádné konstanty.

Příklady

This example shows how to open a CrackLib dictionary, test a given password, retrieve any diagnostic messages, and close the dictionary.

Příklad 1. CrackLib example

<?php // Open CrackLib Dictionary $dictionary = crack_opendict('/usr/local/lib/pw_dict') or die('Unable to open CrackLib dictionary'); // Perform password check $check = crack_check($dictionary, 'gx9A2s0x'); // Retrieve messages $diag = crack_getlastmessage(); echo $diag; // 'strong password' // Close dictionary crack_closedict($dictionary); ?>

Poznámka: If crack_check() returns TRUE, crack_getlastmessage() will return 'strong password'.

Obsah
crack_check -- Performs an obscure check with the given password
crack_closedict -- Closes an open CrackLib dictionary
crack_getlastmessage -- Returns the message from the last obscure check
crack_opendict -- Opens a new CrackLib dictionary

crack_check

(PHP 4 >= 4.0.5)

crack_check -- Performs an obscure check with the given password

Description

bool crack_check ( [resource dictionary, string password])

Returns TRUE if password is strong, or FALSE otherwise.

Varování

Tato funkce je EXPERIMENTÁLNÍ. To znamená, že chování této funkce a její název, přesněji řečeno COKOLI, co je zde zdokumentováno, se v budoucích verzích PHP může BEZ OHLÁŠENÍ změnit. Berte to v úvahu a používejte tuto funkci na vlastní nebezpečí.

crack_check() performs an obscure check with the given password on the specified dictionary . If dictionary is not specified, the last opened dictionary is used.

crack_closedict

(PHP 4 >= 4.0.5)

crack_closedict -- Closes an open CrackLib dictionary

Description

bool crack_closedict ( [resource dictionary])

Vrací TRUE při úspěchu, FALSE při selhání.

Varování

crack_closedict() closes the specified dictionary identifier. If dictionary is not specified, the current dictionary is closed.

crack_getlastmessage

(PHP 4 >= 4.0.5)

crack_getlastmessage -- Returns the message from the last obscure check

Description

string crack_getlastmessage ( void)

Varování

crack_getlastmessage() returns the message from the last obscure check.

crack_opendict

(PHP 4 >= 4.0.5)

crack_opendict -- Opens a new CrackLib dictionary

Description

resource crack_opendict ( string dictionary)

Returns a dictionary resource identifier on success, or FALSE on failure.

Varování

crack_opendict() opens the specified CrackLib dictionary for use with crack_check().

Poznámka: Only one dictionary may be open at a time.

See also: crack_check(), and crack_closedict().

XII. Funkce pro práci s CURL, Client URL Library

PHP podporuje libcurl, knihovnu vytvořenou Danielem Stenbergem, která umožňuje spojení a komunikaci s mnoha různými typy serverů v mnoha různých typech protokolů. libcurl v současné době podporuje http, https, ftp, gopher, telnet, dict, file a ldap protokoly. libcurl také podporuje HTTPS certifikáty, HTTP POST, HTTP PUT, FTP uploady (toto umožňuje i ftp extenze PHP), HTTP formulářové uploady, proxy, cookies a user+password autentikaci.

Pokud chcete používat CURL funkce, musíte nainstalovat CURL. PHP vyžaduje použití CURL 7.0.2-beta nebo vyšší. S verzemi CURL staršími než 7.0.2-beta PHP nebude pracovat.

Dále musíte PHP zkompilovat s --with-curl[=DIR], kde DIR je umístění adresáře obsahujícího lib a include adresáře. V "include" adresáři by měl být adresář pojmenovaný "curl", který by měl obsahovat soubory easy.h and curl.h. V adresáři "lib" by měl být soubor pojmenovaný "libcurl.a".

Tyto funkce byly přidány v PHP 4.0.2.

Pokud máte PHP zkompilované s podporou CURL, můžete začít používat CURL funkce. Základní principem těchto funkcí je, že pomocí curl_init() inicializujete CURL session, potom pomocí curl_exec() nastavíte hodnoty přenosu a nakonec session zavřete pomocí curl_close(). Následuje ukázka, která využíva CURL funkce ke stažení homepage PHP do souboru:

Příklad 1. Použití CURL extenze ke stažení homepage PHP

<?php $ch = curl_init ("http://www.php.net/"); $fp = fopen ("php_homepage.txt", "w"); curl_setopt ($ch, CURLOPT_FILE, $fp); curl_setopt ($ch, CURLOPT_HEADER, 0); curl_exec ($ch); curl_close ($ch); fclose ($fp); ?>

Obsah
curl_close -- Zavřít CURL session
curl_errno -- Return an integer containing the last error number
curl_error -- Return a string containing the last error for the current session
curl_exec -- Provést CURL session
curl_getinfo -- Get information regarding a specific transfer
curl_init -- Inicializovat CURL session
curl_setopt -- Nastavit parametr CURL transferu
curl_version -- Vrátit verzi CURL

curl_close

(PHP 4 >= 4.0.2)

curl_close -- Zavřít CURL session

Popis

void curl_close ( int ch)

Tato funkce zavře CURL session a uvolní všechny zdroje. CURL handle, ch, se také smaže.

curl_errno

(PHP 4 >= 4.0.3)

curl_errno -- Return an integer containing the last error number

Description

int curl_errno ( resource ch)

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

curl_error

(PHP 4 >= 4.0.3)

curl_error -- Return a string containing the last error for the current session

Description

string curl_error ( resource ch)

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

curl_exec

(PHP 4 >= 4.0.2)

curl_exec -- Provést CURL session

Popis

bool curl_exec ( int ch)

Tuto funkci byste měli zavolat po inicializaci CURL session a nastavení všech jejích parametrů. Jejím účelem je provést předdefinovanou CURL session (určenou argumentem ch).

curl_getinfo

(PHP 4 >= 4.0.4)

curl_getinfo -- Get information regarding a specific transfer

Description

string curl_getinfo ( resource ch, int opt)

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

curl_init

(PHP 4 >= 4.0.2)

curl_init -- Inicializovat CURL session

Popis

int curl_init ( [string url])

curl_init() inicializuje novou session a vrací CURL handle pro použití s funkcemi curl_setopt(), curl_exec() a curl_close(). Pokud je přítomen volitelný argument url, CURLOPT_URL se nastaví na hodnotu tohoto argumentu. Můžete to udělat i ručně, pomocí funkce curl_setopt().

Příklad 1. Inicializace nové CURL session a stažení webové stránky

<?php $ch = curl_init(); curl_setopt ($ch, CURLOPT_URL, "http://www.zend.com/"); curl_setopt ($ch, CURLOPT_HEADER, 0); curl_exec ($ch); curl_close ($ch); ?>

Viz také: curl_close(), curl_setopt()

curl_setopt

(PHP 4 >= 4.0.2)

curl_setopt -- Nastavit parametr CURL transferu

Popis

bool curl_setopt ( int ch, string option, mixed value)

curl_setopt() nastavuje parametry CURL session ch. option je parametr, který chcete nastavit a value je hodnota, na kterou se má option nastavit.

Argument value by měl u následujících hodnot argumentu option obsahovat integer:

CURLOPT_INFILESIZE: Tento parametr by měl u uploadů obsahovat velikost uploadovaného souboru.
CURLOPT_VERBOSE: Pokud chcete, aby CURL podávala zprávy o všem co se děje, nastavte tento parametr na nenulovou hodnotu.
CURLOPT_HEADER: Pokud chcete, aby výstup obsahoval hlavičky, nastavte tento parametr na nenulovou hodnotu.
CURLOPT_NOPROGRESS: Pokud PHP nemá zobrazit měřidlo postupu CURL transferu, nastavte tento parametr na nenulovou hodnotu.

Poznámka: PHP tento parametr automaticky nastavuje na nenulovou hodnotu, změna je vhodná pouze pro účely ladění.
CURLOPT_NOBODY: Pokud nechete, aby bylo ve výstupu zahrnuto tělo výstupu, nastavte tento parametr na nenulovou hodnotu.
CURLOPT_FAILONERROR: Pokud má PHP tiše ukončit transfer po přijetí HTTP server kódu většího než 300, nastavte tento parametr na nenulovou hodnotu. Defaultní chování je ignorovat návratový kód a normálně vrátit stránku.
CURLOPT_UPLOAD: Pokud chcete PHP připravit na upload, nastavte tento parametr na nenulovou hodnotu.
CURLOPT_POST: Pokud chcete, aby PHP provedl běžný HTTP POST pořadavek, nastavte tento parametr na nenulovou hodnotu. Jedná se o běžný application/x-www-from-urlencoded POST požadavek, který se většinou používá u HTML formulářů.
CURLOPT_FTPLISTONLY: Pokud chcete, aby PHP vypsalo názvy souborů v FTP adresáři, nastavte tento parametr na nenulovou hodnotu.
CURLOPT_FTPAPPEND: Pokud chcete, aby PHP místo přepsání vzdáleného souboru připojilo upload k jeho obsahu, nastavte tento parametr na nenulovou hodnotu.
CURLOPT_NETRC: Pokud má PHP ve vašem ~./netrc souboru hledat vaše uživatelské jméno a heslo pro server ke kterému se připojujete.
CURLOPT_FOLLOWLOCATION: Pokud má PHP provádět přesměrování u případných "Location: " hlaviček vrácených serverem. (Pozn.: rekurzivní, PHP provede přesměrování pro všechny "Location: " hlavičky, které přijme.)
CURLOPT_PUT: Pokud chcete uploadovat soubor pomocí HTTP metody PUT, nastavte tento parametr na nenulovou hodnotu. Uploadovaný soubor musí být určen parametry CURLOPT_INFILE a CURLOPT_INFILESIZE.
CURLOPT_MUTE: Pokud má být PHP naprosto tiché ohledně CURL funkcí, nastavte tento parametr na nenulovou hodnotu.
CURLOPT_TIMEOUT: Integer určující maximální čas ve vteřinách, který mohou CURL funkce zabrat.
CURLOPT_LOW_SPEED_LIMIT: Integer určující minimální rychlost přenosu v bytech za sekundu. Pokud rychlost přenosu klesne pod tento limit po dobu CURLOPT_LOW_SPEED_TIME sekund, PHP ukončí transfer.
CURLOPT_LOW_SPEED_TIME: Integer určující čas ve vteřinách. Pokud rychlost přenosu klesne na tuto dobu pod CURLOPT_LOW_SPEED_LIMIT, PHP zruší transfer.
CURLOPT_RESUME_FROM: Integer určující offset v bytech, na kterém má transfer začít.
CURLOPT_SSLVERSION: Integer určující, jaká verze SSL (2 nebo 3) se má použít. Defaultně se PHP pokusí určit verzi samo, ale v některých případech je nutno verzi určit manuálně.
CURLOPT_TIMECONDITION: Definující chování CURLOPT_TIMEVALUE. Tento parametr může nabýt buď hodnoty TIMECOND_IFMODSINCE nebo TIMECOND_ISUNMODSINCE. Funguje pouze u HTTP přenosů.
CURLOPT_TIMEVALUE: Integer určující počet vteřin od 1. ledna 1970. Tento čas se použije podle intervalu CURLOPT_TIMEVALUE, default je použití TIMECOND_IFMODSINCE.

Argument value by měl u následujících hodnot argumentu option obsahovat řetězec:

CURLOPT_URL: Toto je URL, kterou má PHP stáhnout. Tento parametr můžete také nastavit při inicializaci CURL session pomocí funkce curl_init().
CURLOPT_USERPWD: Řetězec ve tvaru [username]:[password] pro použití při spojení.
CURLOPT_PROXYUSERPWD: Řetězec ve tvaru [username]:[password] pro použití při spojení s HTTP proxy.
CURLOPT_RANGE: Pass the specified range you want. It should be in the "X-Y" format, where X or Y may be left out. The HTTP transfers also support several intervals, seperated with commas as in X-Y,N-M.
CURLOPT_POSTFIELDS: Řetězec obsahující kompletní data, která se mají odeslat v HTTP POST požadavku.
CURLOPT_REFERER: Řetězec obsahující "referer" hlavičku pro použití v HTTP požadavku.
CURLOPT_USERAGENT: Řetězec obsahující "user-agent" hlavičku pro použití v HTTP požadavku.
CURLOPT_FTPPORT: Řetězec, na jehož základě se získá IP adresa pro FTP "POST" instrukci. POST instrukce říká serveru, aby se připojil na danou IP adresu. Tento řetězec může obsahovat IP adresu, hostname, a network interface name (under UNIX) nebo '-' (použije se defaultní IP adresa systému).
CURLOPT_COOKIE: Řetězec obsahující cookie, který se má poslat v HTTP hlavičce tohoto přenosu.
CURLOPT_SSLCERT: Řetězec obsahující název souboru PEM certifikátu.
CURLOPT_SSLCERTPASSWD: Řetězec obsahující heslo vyžadované pro použití CURLOPT_SSLCERT certifikátu.
CURLOPT_COOKIEFILE: Řetězec obsahující název souboru obsahujícího cookie data. Cookie soubor může být buď v Netscape formátu nebo obsahovat HTTP hlavičky.
CURLOPT_CUSTOMREQUEST: Řetězec, který se má v HTTP požadavku použít místo GET nebo HEAD. Toto je užitečné při DELETE či jiných, obskurnějších HTTP požadavcích.

Poznámka: Používejte pouze v případě, že váš server tento příkaz podporuje.

Následující parametry očekávají deskriptor vrácený funkcí fopen():

CURLOPT_FILE: Soubor, do kterého se má umístit výstup CURL transferu. Default je STDOUT.
CURLOPT_INFILE: Soubor, který obsahuje vstup CURL transferu.
CURLOPT_WRITEHEADER: Soubor, do kterého se mají zapsat hlavičky výstupu.
CURLOPT_STDERR: Soubor, do kterého se mají zapisovat chyby místo na STDERR.

curl_version

(PHP 4 >= 4.0.2)

curl_version -- Vrátit verzi CURL

Popis

string curl_version ( void)

curl_version() vrací řetězec obsahující použitou verzi CURL.

XIII. Cybercash platební funkce

Tyto funkce jsou dostupné pouze pokud bylo PHP zkompilováno s --with-cybercash=[DIR]. Tyto funkce byly přidány v PHP 4.

Obsah
cybercash_base64_decode --
cybercash_base64_encode -- ???
cybercash_decr -- ???
cybercash_encr -- ???

tato funkce vrací asociativní pole s elementem "errcode", a pokud je "errcode" FALSE, "outbuff" (string), "outLth" (long) a "macbuff" (string).

cybercash_encr

(PHP 4 )

cybercash_encr -- ???

Popis

array cybercash_encr ( string wmk, string sk, string inbuff)

Tato funkce vrací asociativní pole s elementem "errcode", a pokud je "errcode" FALSE, "outbuff" (string), "outLth" (long) and "macbuff" (string).

XIV. Crédit Mutuel CyberMUT functions

Úvod

This extension allows you to process credit cards transactions using Crédit Mutuel CyberMUT system (http://www.creditmutuel.fr/centre_commercial/vendez_sur_internet.html).

CyberMUT is a popular Web Payment Service in France, provided by the Crédit Mutuel bank. If you are foreign in France, these functions will not be useful for you.

The use of these functions is almost identical to the original SDK functions, except for the parameters of return for cybermut_creerformulairecm() and cybermut_creerreponsecm(), which are returned directly by functions PHP, whereas they had passed in reference in the original functions.

These functions have been added in PHP 4.0.6.

Poznámka: These functions only provide a link to CyberMUT SDK. Be sure to read the CyberMUT Developers Guide for full details of the required parameters.

Instalace

These functions are only available if PHP has been compiled with the --with-cybermut[=DIR] option, where DIR is the location of libcm-mac.a and cm-mac.h. You will require the appropriate SDK for your platform, which may be sent to you after your CyberMUT's subscription (contact them via Web, or go to the nearest Crédit Mutuel).

Obsah
cybermut_creerformulairecm -- Generate HTML form of request for payment
cybermut_creerreponsecm -- Generate the acknowledgement of delivery of the confirmation of payment
cybermut_testmac -- Make sure that there no was data diddling contained in the received message of confirmation

cybermut_creerformulairecm

(PHP 4 >= 4.0.5)

cybermut_creerformulairecm -- Generate HTML form of request for payment

Description

string cybermut_creerformulairecm ( string url_CM, string version, string TPE, string montant, string ref_commande, string texte_libre, string url_retour, string url_retour_ok, string url_retour_err, string langue, string code_societe, string texte_bouton)

cybermut_creerformulairecm() is used to generate the HTML form of request for payment.

Příklad 1. First step of payment (equiv cgi1.c)

<?php
// Directory where the keys are located
putenv("CMKEYDIR=/var/creditmut/cles");
 
// Version number
$VERSION="1.2";

  $retour =  cybermut_creerformulairecm(
  "https://www.creditmutuel.fr/test/telepaiement/paiement.cgi",
  $VERSION,
  "1234567890",
  "300FRF",
  $REFERENCE,
  $TEXTE_LIBRE,
  $URL_RETOUR,
  $URL_RETOUR_OK,
  $URL_RETOUR_ERR,
  "francais",
  "company",
  "Paiement par carte bancaire");
 
  echo $retour;                                                               
?>

cybermut_creerreponsecm

(PHP 4 >= 4.0.5)

cybermut_creerreponsecm -- Generate the acknowledgement of delivery of the confirmation of payment

Description

string cybermut_creerreponsecm ( string phrase)

cybermut_creerreponsecm() returns a string containing delivery acknowledgement message.

The parameter is "OK" if the message of confirmation of the payment was correctly identified by cybermut_testmac(). Any other chain is regarded as an error message.

cybermut_testmac

(PHP 4 >= 4.0.5)

cybermut_testmac -- Make sure that there no was data diddling contained in the received message of confirmation

Description

bool cybermut_testmac ( string code_MAC, string version, string TPE, string cdate, string montant, string ref_commande, string texte_libre, string code-retour)

cybermut_testmac() is used to make sure that there was not data diddling contained in the received message of confirmation. Pay attention to parameters code-retour and texte-libre, which cannot be evaluated as is, because of the dash. You must retrieve them by using:

<?php $code_retour = $_GET["code-retour"]; $texte_libre = $_GET["texte-libre"]; ?>

Příklad 1. Last step of payment (equiv cgi2.c)

<?php
// Make sure that Enable Track Vars is ON.
// Directory where are located the keys
putenv("CMKEYDIR=/var/creditmut/cles");
 
// Version number
$VERSION="1.2";

$texte_libre = $_GET["texte-libre"];
$code_retour = $_GET["code-retour"];                                     

$mac_ok = cybermut_testmac($MAC,$VERSION,$TPE,$date,$montant,$reference,$texte_libre,$code_retour);

if ($mac_ok) {

  //
  // insert data processing here
  //
  //

  $result=cybermut_creerreponsecm("OK");
} else {
  $result=cybermut_creerreponsecm("Document Falsifie");
}
 
?>

XV. Cyrus IMAP administration functions

Úvod

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

Předdefinované konstanty

Tyto konstanty jsou definovány tímto rozšířením a budou k dispozici pouze tehdy, bylo-li rozšíření zkompilováno společně s PHP nebo dynamicky zavedeno za běhu.

CYRUS_CONN_NONSYNCLITERAL (integer)
CYRUS_CONN_INITIALRESPONSE (integer)
CYRUS_CALLBACK_NUMBERED (integer)
CYRUS_CALLBACK_NOLITERAL (integer)

Obsah
cyrus_authenticate -- Authenticate against a Cyrus IMAP server
cyrus_bind -- Bind callbacks to a Cyrus IMAP connection
cyrus_close -- Close connection to a Cyrus IMAP server
cyrus_connect -- Connect to a Cyrus IMAP server
cyrus_query -- Send a query to a Cyrus IMAP server
cyrus_unbind -- Unbind ...

XVI. Character type functions

Úvod

The functions provided by this extension check whether a character or string falls into a certain character class according to the current locale (see also setlocale()).

When called with an integer argument these functions behave exactly like their C counterparts from "ctype.h".

When called with a string argument they will check every character in the string and will only return TRUE if every character in the string matches the requested criteria. When called with an empty string the result will always be TRUE.

Passing anything else but a string or integer will return FALSE immediately.

Požadavky

None besides functions from the standard C library which are always available.

Instalace

Beginning with PHP 4.2.0 these functions are enabled by default. For older versions you have to configure and compile PHP with --enable-ctype.

Konfigurace běhu

Toto rozšíření nemá definováno žádné konfigurační direktivy.

Typy prostředků

Toto rezšíření nemá definován žádný typ prostředku (resource).

Předdefinované konstanty

Toto rozšíření nemá definovány žádné konstanty.

Obsah
ctype_alnum -- Check for alphanumeric character(s)
ctype_alpha -- Check for alphabetic character(s)
ctype_cntrl -- Check for control character(s)
ctype_digit -- Check for numeric character(s)
ctype_graph -- Check for any printable character(s) except space
ctype_lower -- Check for lowercase character(s)
ctype_print -- Check for printable character(s)
ctype_punct -- Check for any printable character which is not whitespace or an alphanumeric character
ctype_space -- Check for whitespace character(s)
ctype_upper -- Check for uppercase character(s)
ctype_xdigit -- Check for character(s) representing a hexadecimal digit

See also ctype_alpha() and ctype_upper().

ctype_print

(PHP 4 >= 4.0.4)

ctype_print -- Check for printable character(s)

Description

bool ctype_print ( string text)

Returns TRUE if every character in text will actually create output (including blanks). Returns FALSE if text contains control characters or characters that do not have any output or control function at all.

ctype_punct

(PHP 4 >= 4.0.4)

ctype_punct -- Check for any printable character which is not whitespace or an alphanumeric character

Description

bool ctype_punct ( string text)

Returns TRUE if every character in text is printable, but neither letter, digit or blank, FALSE otherwise.

See also ctype_cntrl(), ctype_graph(), and ctype_punct().

ctype_space

(PHP 4 >= 4.0.4)

ctype_space -- Check for whitespace character(s)

Description

bool ctype_space ( string text)

Returns TRUE if every character in text creates some sort of white space, FALSE otherwise. Besides the blank character this also includes tab, vertical tab, line feed, carriage return and form feed characters.

ctype_upper

(PHP 4 >= 4.0.4)

ctype_upper -- Check for uppercase character(s)

Description

bool ctype_upper ( string text)

Returns TRUE if every character in text is a uppercase letter in the current locale.

See also ctype_alpha() and ctype_lower().

ctype_xdigit

(PHP 4 >= 4.0.4)

ctype_xdigit -- Check for character(s) representing a hexadecimal digit

Description

bool ctype_xdigit ( string text)

Returns TRUE if every character in text is a hexadecimal 'digit', that is a decimal digit or a character from [A-Fa-f] , FALSE otherwise.

XVII. Database (dbm-style) abstraction layer functions

Úvod

These functions build the foundation for accessing Berkeley DB style databases.

This is a general abstraction layer for several file-based databases. As such, functionality is limited to a common subset of features supported by modern databases such as Sleepycat Software's DB2. (This is not to be confused with IBM's DB2 software, which is supported through the ODBC functions.)

Požadavky

The behaviour of various aspects depends on the implementation of the underlying database. Functions such as dba_optimize() and dba_sync() will do what they promise for one database and will do nothing for others. You have to download and install supported dba-Handlers.

Tabulka 1. List of DBA handlers

Handler	Notes
`dbm`	Dbm is the oldest (original) type of Berkeley DB style databases. You should avoid it, if possible. We do not support the compatibility functions built into DB2 and gdbm, because they are only compatible on the source code level, but cannot handle the original dbm format.
`ndbm`	Ndbm is a newer type and more flexible than dbm. It still has most of the arbitrary limits of dbm (therefore it is deprecated).
`gdbm`	Gdbm is the GNU database manager.
`db2`	DB2 is Sleepycat Software's DB2. It is described as "a programmatic toolkit that provides high-performance built-in database support for both standalone and client/server applications.
`db3`	DB3 is Sleepycat Software's DB3.
`cdb`	Cdb is "a fast, reliable, lightweight package for creating and reading constant databases." It is from the author of qmail and can be found here. Since it is constant, we support only reading operations.

When invoking the dba_open() or dba_popen() functions, one of the handler names must be supplied as an argument. The actually available list of handlers is displayed by invoking phpinfo().

Instalace

By using the --enable-dba=shared configuration option you can build a dynamic loadable modul to enable PHP for basic support of dbm-style databases. You also have to add support for at least one of the following handlers by specifying the --with-XXXX configure switch to your PHP configure line.

Tabulka 2. Supported DBA handlers

Handler	Configure Switch
`dbm`	To enable support for dbm add `--with-dbm[=DIR]`.
`ndbm`	To enable support for ndbm add `--with-ndbm[=DIR]`.
`gdbm`	To enable support for gdbm add `--with-gdbm[=DIR]`.
`db2`	To enable support for db2 add `--with-db2[=DIR]`.
`db3`	To enable support for db3 add `--with-db3[=DIR]`.
`cdb`	To enable support for cdb add `--with-cdb[=DIR]`.

Konfigurace běhu

Toto rozšíření nemá definováno žádné konfigurační direktivy.

Typy prostředků

The functions dba_open() and dba_popen() return a handle to the specified database file to access which is used by all other dba-function calls.

Předdefinované konstanty

Toto rozšíření nemá definovány žádné konstanty.

Příklady

Příklad 1. DBA example

<?php $id = dba_open ("/tmp/test.db", "n", "db2"); if (!$id) { echo "dba_open failed\n"; exit; } dba_replace ("key", "This is an example!", $id); if (dba_exists ("key", $id)) { echo dba_fetch ("key", $id); dba_delete ("key", $id); } dba_close ($id); ?>

DBA is binary safe and does not have any arbitrary limits. However, it inherits all limits set by the underlying database implementation.

All file-based databases must provide a way of setting the file mode of a new created database, if that is possible at all. The file mode is commonly passed as the fourth argument to dba_open() or dba_popen().

You can access all entries of a database in a linear way by using the dba_firstkey() and dba_nextkey() functions. You may not change the database while traversing it.

Příklad 2. Traversing a database

<?php // ...open database... $key = dba_firstkey ($id); while ($key != false) { if (...) { // remember the key to perform some action later $handle_later[] = $key; } $key = dba_nextkey ($id); } for ($i = 0; $i < count($handle_later); $i++) dba_delete ($handle_later[$i], $id); ?>

Obsah
dba_close -- Close database
dba_delete -- Delete entry specified by key
dba_exists -- Check whether key exists
dba_fetch -- Fetch data specified by key
dba_firstkey -- Fetch first key
dba_insert -- Insert entry
dba_nextkey -- Fetch next key
dba_open -- Open database
dba_optimize -- Optimize database
dba_popen -- Open database persistently
dba_replace -- Replace or insert entry
dba_sync -- Synchronize database

dba_insert() returns TRUE or FALSE, depending on whether it succeeds of fails, respectively.

dba_nextkey

(PHP 3>= 3.0.8, PHP 4 )

dba_nextkey -- Fetch next key

Description

string dba_nextkey ( resource handle)

dba_nextkey() returns the next key of the database specified by handle and advances the internal key pointer.

handle is a database handle returned by dba_open().

dba_nextkey() returns the key or FALSE depending on whether it succeeds or fails, respectively.

See also: dba_firstkey() and example 2 in the DBA examples

dba_open

(PHP 3>= 3.0.8, PHP 4 )

dba_open -- Open database

Description

resource dba_open ( string path, string mode, string handler [, ...])

dba_open() establishes a database instance for path with mode using handler.

path is commonly a regular path in your filesystem.

mode is "r" for read access, "w" for read/write access to an already existing database, "c" for read/write access and database creation if it doesn't currently exist, and "n" for create, truncate and read/write access.

handler is the name of the handler which shall be used for accessing path. It is passed all optional parameters given to dba_open() and can act on behalf of them.

dba_open() returns a positive handle or FALSE, in the case the open is successful or fails, respectively.

dba_optimize

(PHP 3>= 3.0.8, PHP 4 )

dba_optimize -- Optimize database

Description

bool dba_optimize ( resource handle)

dba_optimize() optimizes the underlying database specified by handle.

handle is a database handle returned by dba_open().

dba_optimize() returns TRUE or FALSE, if the optimization succeeds or fails, respectively.

dba_popen

(PHP 3>= 3.0.8, PHP 4 )

dba_popen -- Open database persistently

Description

resource dba_popen ( string path, string mode, string handler [, ...])

dba_popen() establishes a persistent database instance for path with mode using handler.

path is commonly a regular path in your filesystem.

handler is the name of the handler which shall be used for accessing path. It is passed all optional parameters given to dba_popen() and can act on behalf of them.

dba_popen() returns a positive handle or FALSE, in the case the open is successful or fails, respectively.

dba_replace

(PHP 3>= 3.0.8, PHP 4 )

dba_replace -- Replace or insert entry

Description

bool dba_replace ( string key, string value, resource handle)

dba_replace() replaces or inserts the entry described with key and value into the database specified by handle.

key is the key of the entry to be inserted.

value is the value to be inserted.

handle is a database handle returned by dba_open().

dba_replace() returns TRUE or FALSE, depending on whether it succeeds of fails, respectively.

dba_sync

(PHP 3>= 3.0.8, PHP 4 )

dba_sync -- Synchronize database

Description

bool dba_sync ( resource handle)

dba_sync() synchronizes the database specified by handle. This will probably trigger a physical write to disk, if supported.

handle is a database handle returned by dba_open().

dba_sync() returns TRUE or FALSE, if the synchronization succeeds or fails, respectively.

XVIII. Date and Time functions

Úvod

You can use this functions to handle date and time. This functions allow you to get date and time from the server where PHP is running on. You can use this functions to format the output of date and time in many different ways.

Poznámka: Please keep in mind that this functions are depending on the locale settings of your server. Especially consider daylight saving time settings and leap years.

Požadavky

Tyto funkce jsou k dispozici jako součást standardního modulu, který je vždy dostupný.

Instalace

K používání těchto funkcí není třeba žádná instalace, jsou součástí jádra PHP.

Konfigurace běhu

Toto rozšíření nemá definováno žádné konfigurační direktivy.

Typy prostředků

Toto rezšíření nemá definován žádný typ prostředku (resource).

Předdefinované konstanty

Toto rozšíření nemá definovány žádné konstanty.

Obsah
checkdate -- Validate a gregorian date/time
date -- Format a local time/date
getdate -- Get date/time information
gettimeofday -- Get current time
gmdate -- Format a GMT/CUT date/time
gmmktime -- Get UNIX timestamp for a GMT date
gmstrftime -- Format a GMT/CUT time/date according to locale settings
localtime -- Get the local time
microtime -- Return current UNIX timestamp with microseconds
mktime -- Get UNIX timestamp for a date
strftime -- Format a local time/date according to locale settings
strtotime -- Parse about any English textual datetime description into a UNIX timestamp
time -- Return current UNIX timestamp

checkdate

(PHP 3, PHP 4 )

checkdate -- Validate a gregorian date/time

Description

bool checkdate ( int month, int day, int year)

Returns TRUE if the date given is valid; otherwise returns FALSE. Checks the validity of the date formed by the arguments. A date is considered valid if:

year is between 1 and 32767 inclusive
month is between 1 and 12 inclusive
Day is within the allowed number of days for the given month. Leap years are taken into consideration.

See also mktime() and strtotime().

date

(PHP 3, PHP 4 )

date -- Format a local time/date

Description

string date ( string format [, int timestamp])

Returns a string formatted according to the given format string using the given integer timestamp or the current local time if no timestamp is given.

Poznámka: The valid range of a timestamp is typically from Fri, 13 Dec 1901 20:45:54 GMT to Tue, 19 Jan 2038 03:14:07 GMT. (These are the dates that correspond to the minimum and maximum values for a 32-bit signed integer). On windows this range is limited from 01-01-1970 to 19-01-2038.

To generate a timestamp from a string representation of the date, you may be able to use strtotime(). Additionally, some databases have functions to convert their date formats into timestamps (such as MySQL's UNIX_TIMESTAMP function).

The following characters are recognized in the format string:

a - "am" or "pm"
A - "AM" or "PM"
B - Swatch Internet time
d - day of the month, 2 digits with leading zeros; i.e. "01" to "31"
D - day of the week, textual, 3 letters; e.g. "Fri"
F - month, textual, long; e.g. "January"
g - hour, 12-hour format without leading zeros; i.e. "1" to "12"
G - hour, 24-hour format without leading zeros; i.e. "0" to "23"
h - hour, 12-hour format; i.e. "01" to "12"
H - hour, 24-hour format; i.e. "00" to "23"
i - minutes; i.e. "00" to "59"
I (capital i) - "1" if Daylight Savings Time, "0" otherwise.
j - day of the month without leading zeros; i.e. "1" to "31"
l (lowercase 'L') - day of the week, textual, long; e.g. "Friday"
L - boolean for whether it is a leap year; i.e. "0" or "1"
m - month; i.e. "01" to "12"
M - month, textual, 3 letters; e.g. "Jan"
n - month without leading zeros; i.e. "1" to "12"
O - Difference to Greenwich time in hours; e.g. "+0200"
r - RFC 822 formatted date; e.g. "Thu, 21 Dec 2000 16:01:07 +0200" (added in PHP 4.0.4)
s - seconds; i.e. "00" to "59"
S - English ordinal suffix for the day of the month, 2 characters; i.e. "st", "nd", "rd" or "th"
t - number of days in the given month; i.e. "28" to "31"
T - Timezone setting of this machine; e.g. "EST" or "MDT"
U - seconds since the Unix Epoch (January 1 1970 00:00:00 GMT)
w - day of the week, numeric, i.e. "0" (Sunday) to "6" (Saturday)
W - ISO-8601 week number of year, weeks starting on Monday (added in PHP 4.1.0)
Y - year, 4 digits; e.g. "1999"
y - year, 2 digits; e.g. "99"
z - day of the year; i.e. "0" to "365"
Z - timezone offset in seconds (i.e. "-43200" to "43200"). The offset for timezones west of UTC is always negative, and for those east of UTC is always positive.

Unrecognized characters in the format string will be printed as-is. The "Z" format will always return "0" when using gmdate().

Příklad 1. date() example

echo date ("l dS of F Y h:i:s A"); echo "July 1, 2000 is on a " . date ("l", mktime(0,0,0,7,1,2000));

You can prevent a recognized character in the format string from being expanded by escaping it with a preceding backslash. If the character with a backslash is already a special sequence, you may need to also escape the backslash.

Příklad 2. Escaping characters in date()

echo date("l \\t\h\e jS"); // prints something like 'Saturday the 8th'

It is possible to use date() and mktime() together to find dates in the future or the past.

Příklad 3. date() and mktime() example

$tomorrow = mktime (0,0,0,date("m") ,date("d")+1,date("Y")); $lastmonth = mktime (0,0,0,date("m")-1,date("d"), date("Y")); $nextyear = mktime (0,0,0,date("m"), date("d"), date("Y")+1);

Poznámka: This can be more reliable than simply adding or subtracting the number of seconds in a day or month to a timestamp because of daylight savings time.

Some examples of date() formatting. Note that you should escape any other characters, as any which currently have a special meaning will produce undesirable results, and other characters may be assigned meaning in future PHP versions. When escaping, be sure to use single quotes to prevent characters like \n from becoming newlines.

Příklad 4. date() Formatting

/* Today is March 10th, 2001, 5:16:18 pm */ $today = date("F j, Y, g:i a"); // March 10, 2001, 5:16 pm $today = date("m.d.y"); // 03.10.01 $today = date("j, n, Y"); // 10, 3, 2001 $today = date("Ymd"); // 20010310 $today = date('h-i-s, j-m-y, it is w Day z '); // 05-16-17, 10-03-01, 1631 1618 6 Fripm01 $today = date('\i\t \i\s \t\h\e jS \d\a\y.'); // It is the 10th day. $today = date("D M j G:i:s T Y"); // Sat Mar 10 15:16:08 MST 2001 $today = date('H:m:s \m \i\s\ \m\o\n\t\h'); // 17:03:17 m is month $today = date("H:i:s"); // 17:16:17

To format dates in other languages, you should use the setlocale() and strftime() functions.

getdate

(PHP 3, PHP 4 )

getdate -- Get date/time information

Description

array getdate ( [int timestamp])

Returns an associative array containing the date information of the timestamp, or the current local time if no timestamp is given, as the following array elements:

"seconds" - seconds
"minutes" - minutes
"hours" - hours
"mday" - day of the month
"wday" - day of the week, numeric : from 0 as Sunday up to 6 as Saturday
"mon" - month, numeric
"year" - year, numeric
"yday" - day of the year, numeric; i.e. "299"
"weekday" - day of the week, textual, full; i.e. "Friday"
"month" - month, textual, full; i.e. "January"

Příklad 1. getdate() example

$today = getdate(); 
$month = $today['month']; 
$mday = $today['mday']; 
$year = $today['year']; 
echo "$month $mday, $year";

gettimeofday

(PHP 3>= 3.0.7, PHP 4 )

gettimeofday -- Get current time

Description

array gettimeofday ( void)

This is an interface to gettimeofday(2). It returns an associative array containing the data returned from the system call.

"sec" - seconds
"usec" - microseconds
"minuteswest" - minutes west of Greenwich
"dsttime" - type of dst correction

"tm_sec" - seconds
"tm_min" - minutes
"tm_hour" - hour
"tm_mday" - day of the month
"tm_mon" - month of the year, starting with 0 for January
"tm_year" - Years since 1900
"tm_wday" - Day of the week
"tm_yday" - Day of the year
"tm_isdst" - Is daylight savings time in effect

microtime

(PHP 3, PHP 4 )

microtime -- Return current UNIX timestamp with microseconds

Description

string microtime ( void)

Returns the string "msec sec" where sec is the current time measured in the number of seconds since the Unix Epoch (0:00:00 January 1, 1970 GMT), and msec is the microseconds part. This function is only available on operating systems that support the gettimeofday() system call.

Both portions of the string are returned in units of seconds.

Příklad 1. microtime() example

function getmicrotime(){ list($usec, $sec) = explode(" ",microtime()); return ((float)$usec + (float)$sec); } $time_start = getmicrotime(); for ($i=0; $i < 1000; $i++){ //do nothing, 1000 times } $time_end = getmicrotime(); $time = $time_end - $time_start; echo "Did nothing in $time seconds";

mktime

(PHP 3, PHP 4 )

mktime -- Get UNIX timestamp for a date

Description

int mktime ( int hour, int minute, int second, int month, int day, int year [, int is_dst])

Warning: Note the strange order of arguments, which differs from the order of arguments in a regular UNIX mktime() call and which does not lend itself well to leaving out parameters from right to left (see below). It is a common error to mix these values up in a script.

Returns the Unix timestamp corresponding to the arguments given. This timestamp is a long integer containing the number of seconds between the Unix Epoch (January 1 1970) and the time specified.

Arguments may be left out in order from right to left; any arguments thus omitted will be set to the current value according to the local date and time.

is_dst can be set to 1 if the time is during daylight savings time, 0 if it is not, or -1 (the default) if it is unknown whether the time is within daylight savings time or not. If it's unknown, PHP tries to figure it out itself. This can cause unexpected (but not incorrect) results.

Poznámka: is_dst was added in 3.0.10.

mktime() is useful for doing date arithmetic and validation, as it will automatically calculate the correct value for out-of-range input. For example, each of the following lines produces the string "Jan-01-1998".

Příklad 1. mktime() example

echo date ("M-d-Y", mktime (0,0,0,12,32,1997)); echo date ("M-d-Y", mktime (0,0,0,13,1,1997)); echo date ("M-d-Y", mktime (0,0,0,1,1,1998)); echo date ("M-d-Y", mktime (0,0,0,1,1,98));
Year may be a two or four digit value, with values between 0-69 mapping to 2000-2069 and 70-99 to 1970-1999 (on systems where time_t is a 32bit signed integer, as most common today, the valid range for year is somewhere between 1902 and 2037).

The last day of any given month can be expressed as the "0" day of the next month, not the -1 day. Both of the following examples will produce the string "The last day in Feb 2000 is: 29".

Příklad 2. Last day of next month

$lastday = mktime (0,0,0,3,0,2000); echo strftime ("Last day in Feb 2000 is: %d", $lastday); $lastday = mktime (0,0,0,4,-31,2000); echo strftime ("Last day in Feb 2000 is: %d", $lastday);

Date with year, month and day equal to zero is considered illegal (otherwise it what be regarded as 30.11.1999, which would be strange behavior).

strftime

(PHP 3, PHP 4 )

strftime -- Format a local time/date according to locale settings

Description

string strftime ( string format [, int timestamp])

Returns a string formatted according to the given format string using the given timestamp or the current local time if no timestamp is given. Month and weekday names and other language dependent strings respect the current locale set with setlocale().

The following conversion specifiers are recognized in the format string:

%a - abbreviated weekday name according to the current locale
%A - full weekday name according to the current locale
%b - abbreviated month name according to the current locale
%B - full month name according to the current locale
%c - preferred date and time representation for the current locale
%C - century number (the year divided by 100 and truncated to an integer, range 00 to 99)
%d - day of the month as a decimal number (range 01 to 31)
%D - same as %m/%d/%y
%e - day of the month as a decimal number, a single digit is preceded by a space (range ' 1' to '31')
%g - like %G, but without the century.
%G - The 4-digit year corresponding to the ISO week number (see %V). This has the same format and value as %Y, except that if the ISO week number belongs to the previous or next year, that year is used instead.
%h - same as %b
%H - hour as a decimal number using a 24-hour clock (range 00 to 23)
%I - hour as a decimal number using a 12-hour clock (range 01 to 12)
%j - day of the year as a decimal number (range 001 to 366)
%m - month as a decimal number (range 01 to 12)
%M - minute as a decimal number
%n - newline character
%p - either `am' or `pm' according to the given time value, or the corresponding strings for the current locale
%r - time in a.m. and p.m. notation
%R - time in 24 hour notation
%S - second as a decimal number
%t - tab character
%T - current time, equal to %H:%M:%S
%u - weekday as a decimal number [1,7], with 1 representing Monday

Varování

Sun Solaris seems to start with Sunday as 1 although ISO 9889:1999 (the current C standard) clearly specifies that it should be Monday.
%U - week number of the current year as a decimal number, starting with the first Sunday as the first day of the first week
%V - The ISO 8601:1988 week number of the current year as a decimal number, range 01 to 53, where week 1 is the first week that has at least 4 days in the current year, and with Monday as the first day of the week. (Use %G or %g for the year component that corresponds to the week number for the specified timestamp.)
%W - week number of the current year as a decimal number, starting with the first Monday as the first day of the first week
%w - day of the week as a decimal, Sunday being 0
%x - preferred date representation for the current locale without the time
%X - preferred time representation for the current locale without the date
%y - year as a decimal number without a century (range 00 to 99)
%Y - year as a decimal number including the century
%Z - time zone or name or abbreviation
%% - a literal `%' character

Poznámka: Not all conversion specifiers may be supported by your C library, in which case they will not be supported by PHP's strftime(). This means that %T and %D will not work on Windows.

Příklad 1. strftime() example

setlocale (LC_TIME, "C");
print (strftime ("%A in Finnish is "));
setlocale (LC_TIME, "fi_FI");
print (strftime ("%A, in French "));
setlocale (LC_TIME, "fr_FR");
print (strftime ("%A and in German "));
setlocale (LC_TIME, "de_DE");
print (strftime ("%A.\n"));

This example works if you have the respective locales installed in your system.

strtotime

(PHP 3>= 3.0.12, PHP 4 )

strtotime -- Parse about any English textual datetime description into a UNIX timestamp

Description

int strtotime ( string time [, int now])

The function expects to be given a string containing an English date format and will try to parse that format into a UNIX timestamp relative to the timestamp given in now, or the current time if none is supplied. Upon failure, -1 is returned.

Because strtotime() behaves according to GNU date syntax, have a look at the GNU manual page titled Date Input Formats. Described there is valid syntax for the time parameter.

Příklad 1. strtotime() examples

echo strtotime ("now"), "\n"; echo strtotime ("10 September 2000"), "\n"; echo strtotime ("+1 day"), "\n"; echo strtotime ("+1 week"), "\n"; echo strtotime ("+1 week 2 days 4 hours 2 seconds"), "\n"; echo strtotime ("next Thursday"), "\n"; echo strtotime ("last Monday"), "\n";

Příklad 2. Checking for failure

$str = 'Not Good'; if (($timestamp = strtotime($str)) === -1) { echo "The string ($str) is bogus"; } else { echo "$str == ". date('l dS of F Y h:i:s A',$timestamp); }

Poznámka: The valid range of a timestamp is typically from Fri, 13 Dec 1901 20:45:54 GMT to Tue, 19 Jan 2038 03:14:07 GMT. (These are the dates that correspond to the minimum and maximum values for a 32-bit signed integer.)

time

(PHP 3, PHP 4 )

time -- Return current UNIX timestamp

Description

int time ( void)

Returns the current time measured in the number of seconds since the Unix Epoch (January 1 1970 00:00:00 GMT).

XIX. dBase functions

Úvod

These functions allow you to access records stored in dBase-format (dbf) databases.

There is no support for indexes or memo fields. There is no support for locking, too. Two concurrent webserver processes modifying the same dBase file will very likely ruin your database.

dBase files are simple sequential files of fixed length records. Records are appended to the end of the file and delete records are kept until you call dbase_pack().

We recommend that you do not use dBase files as your production database. Choose any real SQL server instead; MySQL or Postgres are common choices with PHP. dBase support is here to allow you to import and export data to and from your web database, because the file format is commonly understood by Windows spreadsheets and organizers.

Instalace

In order to use these functions, you must compile PHP with the --enable-dbase option.

Konfigurace běhu

Toto rozšíření nemá definováno žádné konfigurační direktivy.

Typy prostředků

Toto rezšíření nemá definován žádný typ prostředku (resource).

Předdefinované konstanty

Toto rozšíření nemá definovány žádné konstanty.

Obsah
dbase_add_record -- Add a record to a dBase database
dbase_close -- Close a dBase database
dbase_create -- Creates a dBase database
dbase_delete_record -- Deletes a record from a dBase database
dbase_get_record_with_names -- Gets a record from a dBase database as an associative array
dbase_get_record -- Gets a record from a dBase database
dbase_numfields -- Find out how many fields are in a dBase database
dbase_numrecords -- Find out how many records are in a dBase database
dbase_open -- Opens a dBase database
dbase_pack -- Packs a dBase database
dbase_replace_record -- Replace a record in a dBase database

dbase_add_record

array dbase_get_record_with_names ( int dbase_identifier, int record)

Returns the data from record in an associative array. The array also includes an associative member named 'deleted' which is set to 1 if the record has been marked for deletion (see dbase_delete_record()).

Each field is converted to the appropriate PHP type, except:

Dates are left as strings
Integers that would have caused an overflow (> 32 bits) are returned as strings

dbase_get_record

(PHP 3, PHP 4 )

dbase_get_record -- Gets a record from a dBase database

Description

array dbase_get_record ( int dbase_identifier, int record)

Returns the data from record in an array. The array is indexed starting at 0, and includes an associative member named 'deleted' which is set to 1 if the record has been marked for deletion (see dbase_delete_record().

Each field is converted to the appropriate PHP type, except:

Dates are left as strings
Integers that would have caused an overflow (> 32 bits) are returned as strings

Returns a dbase_identifier for the opened database, or FALSE if the database couldn't be opened.

Poznámka: Pokud je zapnut bezpečný režim (safe-mode), PHP kontroluje, zda soubory/adresáře, se kterými pracujete, mají stejné UID jako spuštěný skript.

dbase_pack

(PHP 3, PHP 4 )

dbase_pack -- Packs a dBase database

Description

bool dbase_pack ( int dbase_identifier)

Packs the specified database (permanently deleting all records marked for deletion using dbase_delete_record()).

dbase_replace_record

(PHP 3>= 3.0.11, PHP 4 )

dbase_replace_record -- Replace a record in a dBase database

Description

bool dbase_replace_record ( int dbase_identifier, array record, int dbase_record_number)

Replaces the data associated with the record record_number with the data in the record in the database. If the number of items in the supplied record is not equal to the number of fields in the database, the operation will fail and FALSE will be returned.

dbase_record_number is an integer which spans from 1 to the number of records in the database (as returned by dbase_numrecords()).

XX. DBM Funkce

Tyto funkce vám umožňují ukládat záznamy do databází typu dbm. Tento typ databází (podporovaný Berkeley DB, GDBM, některými systémovými knihovnami, a také vestavěnou flatfile knihovnou) ukládá klíč/hodnota páry (oproti plnohodnotným relačním databázím).

Příklad 1. Ukázka DBM

$dbm = dbmopen ("lastseen", "w"); if (dbmexists ($dbm, $userid)) { $last_seen = dbmfetch ($dbm, $userid); } else { dbminsert ($dbm, $userid, time()); } do_stuff(); dbmreplace ($dbm, $userid, time()); dbmclose ($dbm);

Obsah
dblist -- Získat název používané DBM-kompatibilní knihovny
dbmclose -- Zavřít dbm databázi
dbmdelete -- Smazat v DMB databázi hodnotu spojenou s určitým klíčem
dbmexists -- Zjistí, jestli pro zadaný klíč existuje v DBM databázi hodnota
dbmfetch -- Získat z DBM databáze hodnotu spojenou s určitým klíčem
dbmfirstkey -- Získat z DBM databáze první klíč
dbminsert -- Vložit do DBM databáze hodnotu a klíč
dbmnextkey -- Získat další klíč z DBM databáze
dbmopen -- Otevřít DBM databázi
dbmreplace -- Nahredit v DBM databázi hodnotu s určitým klíčem

dblist

(PHP 3, PHP 4 )

dblist -- Získat název používané DBM-kompatibilní knihovny

Popis

string dblist ( void)

dbmclose

(PHP 3, PHP 4 )

dbmclose -- Zavřít dbm databázi

Popis

bool dbmclose ( int dbm_identifier)

Odemkne a zavře určenou databázi.

dbmdelete

(PHP 3, PHP 4 )

dbmdelete -- Smazat v DMB databázi hodnotu spojenou s určitým klíčem

Popis

bool dbmdelete ( int dbm_identifier, string key)

int dbminsert ( int dbm_identifier, string key, string value)

Přidá do databáze hodnotu s určeným klíčem.

Vrací -1, pokud byla databáze otevřena pouze pro čtení, 0, pokud bylo vložení úspěšné, a 1, pokud už určený klíč existuje. (K nahražení hodnoty použijte dbmreplace().)

dbmnextkey

(PHP 3, PHP 4 )

dbmnextkey -- Získat další klíč z DBM databáze

Popis

string dbmnextkey ( int dbm_identifier, string key)

Vrací klíč násůedující po key. Zavoláním dbmfirstkey() následovaným postupným voláním dbmnextkey() se dají získat všechny key/value páry v DBM databázi. Například:

Příklad 1. Získání všech key/value párů v DBM databázi

$key = dbmfirstkey ($dbm_id); while ($key) { echo "$key = " . dbmfetch ($dbm_id, $key) . "\n"; $key = dbmnextkey ($dbm_id, $key); }

dbmopen

(PHP 3, PHP 4 )

dbmopen -- Otevřít DBM databázi

Popis

int dbmopen ( string filename, string flags)

První argument je název DBM souboru (plná cesta), který se má otevřít, druhý argument je jedno z "r" (pouze pro čtení), "n" (nový, implikuje čtení/zápis, a nejspíš smaže existující databázi stejného jména), "c" (vytvořit, implikuje čtení/zápis, a nesmaže existující databázi stejného jména) nebo "w" (čtení/zápis).

Při úspěchu vrací identifikátor, který se předává dalším DBM funkcím success, jinak FALSE.

Pokud používáte NDBM, NDBM ve skutečnosti vytváří soubory soubor.dir a soubor.pag. GDBM používá pouze jeden soubr, stejně jako interní flatfile podpora, a Berkeley DB vytváří soubor filename.db. Pozn.: Vedle případného zamykání souborů vlastní DBM knihovnou provádí PHP svoje vlastní zamykání souborů. PHP nemaže .lck soubory, které vytváří. Používá tyto soubory jako pevné inodes, na kterých provádí zamykání souborů. Více informací o DBM souborech viz vaše Unixové man stránky, nebo si stáhněte GNU GDBM.

dbmreplace

(PHP 3, PHP 4 )

dbmreplace -- Nahredit v DBM databázi hodnotu s určitým klíčem

Popis

bool dbmreplace ( int dbm_identifier, string key, string value)

Nahradí v databázi hodnotu spojenou s určeným klíčem.

Pokud tento klíče v databázi neexistuje, přidá ho.

XXI. dbx functions

Úvod

The dbx module is a database abstraction layer (db 'X', where 'X' is a supported database). The dbx functions allow you to access all supported databases using a single calling convention. The dbx-functions themselves do not interface directly to the databases, but interface to the modules that are used to support these databases.

Požadavky

To be able to use a database with the dbx-module, the module must be either linked or loaded into PHP, and the database module must be supported by the dbx-module. Currently, following databases are supported, but others will follow (soon, I hope :-):

FrontBase (available from PHP 4.1.0).
Microsoft SQL Server
MySQL
ODBC
PostgreSQL
Sybase-CT (available from PHP 4.2.0).

Documentation for adding additional database support to dbx can be found at http://www.guidance.nl/php/dbx/doc/.

Instalace

In order to have these functions available, you must compile PHP with dbx support by using the --enable-dbx option and all options for the databases that will be used, e.g. for MySQL you must also specify --with-mysql=[DIR]. To get other supported databases to work with the dbx-module refer to their specific documentation.

Konfigurace běhu

Toto rozšíření nemá definováno žádné konfigurační direktivy.

Typy prostředků

There are two resource types used in the dbx module. The first one is the link-object for a database connection, the second a result-object which helds the result of a query.

Předdefinované konstanty

Tyto konstanty jsou definovány tímto rozšířením a budou k dispozici pouze tehdy, bylo-li rozšíření zkompilováno společně s PHP nebo dynamicky zavedeno za běhu.

DBX_MYSQL (integer)
DBX_ODBC (integer)
DBX_PGSQL (integer)
DBX_MSSQL (integer)
DBX_FBSQL (integer)
DBX_OCI8 (integer)
DBX_SYBASECT (integer)
DBX_PERSISTENT (integer)
DBX_RESULT_INFO (integer)
DBX_RESULT_INDEX (integer)
DBX_RESULT_ASSOC (integer)
DBX_CMP_NATIVE (integer)
DBX_CMP_TEXT (integer)
DBX_CMP_NUMBER (integer)
DBX_CMP_ASC (integer)
DBX_CMP_DESC (integer)

Obsah
dbx_close -- Close an open connection/database
dbx_compare -- Compare two rows for sorting purposes
dbx_connect -- Open a connection/database
dbx_error -- Report the error message of the latest function call in the module (not just in the connection)
dbx_query -- Send a query and fetch all results (if any)
dbx_sort -- Sort a result from a dbx_query by a custom sort function

dbx_close

(PHP 4 >= 4.0.6)

dbx_close -- Close an open connection/database

Description

bool dbx_close ( object link_identifier)

Vrací TRUE při úspěchu, FALSE při selhání.

Příklad 1. dbx_close() example

<?php
$link = dbx_connect(DBX_MYSQL, "localhost", "db", "username", "password")
    or die ("Could not connect");

print("Connected successfully");
dbx_close($link);
?>

Poznámka: Always refer to the module-specific documentation as well.

dbx_compare

(PHP 4 >= 4.1.0)

dbx_compare -- Compare two rows for sorting purposes

Description

int dbx_compare ( array row_a, array row_b, string column_key [, int flags])

dbx_compare() returns 0 if the row_a[$column_key] is equal to row_b[$column_key], and 1 or -1 if the former is greater or is smaller than the latter one, respectively, or vice versa if the flag is set to DBX_CMP_DESC. dbx_compare() is a helper function for dbx_sort() to ease the make and use of the custom sorting function.

The flags can be set to specify comparison direction:

DBX_CMP_ASC - ascending order
DBX_CMP_DESC - descending order

and the preferred comparison type:

DBX_CMP_NATIVE - no type conversion
DBX_CMP_TEXT - compare items as strings
DBX_CMP_NUMBER - compare items numerically

One of the direction and one of the type constant can be combined with bitwise OR operator (|). The default value for the flags parameter is DBX_CMP_ASC | DBX_CMP_NATIVE.

Příklad 1. dbx_compare() example

<?php
function user_re_order ($a, $b) {
    $rv = dbx_compare ($a, $b, "parentid", DBX_CMP_DESC);
    if ( !$rv ) {
        $rv = dbx_compare ($a, $b, "id", DBX_CMP_NUMBER);
    }
    return $rv;
}

$link   = dbx_connect (DBX_ODBC, "", "db", "username", "password")
    or die ("Could not connect");

$result = dbx_query ($link, "SELECT id, parentid, description FROM table ORDER BY id");
    // data in $result is now ordered by id

dbx_sort ($result, "user_re_order");
    // date in $result is now ordered by parentid (descending), then by id

dbx_close ($link);
?>

dbx_connect

(PHP 4 >= 4.0.6)

dbx_connect -- Open a connection/database

Description

object dbx_connect ( mixed module, string host, string database, string username, string password [, int persistent])

dbx_connect() returns an object on success, FALSE on error. If a connection has been made but the database could not be selected, the connection is closed and FALSE is returned. The persistent parameter can be set to DBX_PERSISTENT, if so, a persistent connection will be created.

The module parameter can be either a string or a constant, though the latter form is preferred. The possible values are given below, but keep in mind that they only work if the module is actually loaded.

DBX_MYSQL or "mysql"
DBX_ODBC or "odbc"
DBX_PGSQL or "pgsql"
DBX_MSSQL or "mssql"
DBX_FBSQL or "fbsql" (available from PHP 4.1.0)
DBX_SYBASECT or "sybase_ct" (available from PHP 4.2.0)

The host, database, username and password parameters are expected, but not always used depending on the connect functions for the abstracted module.

The returned object has three properties:

database

It is the name of the currently selected database.

handle

It is a valid handle for the connected database, and as such it can be used in module-specific functions (if required).

$link = dbx_connect (DBX_MYSQL, "localhost", "db", "username", "password");
mysql_close ($link->handle); // dbx_close($link) would be better here

module

It is used internally by dbx only, and is actually the module number mentioned above.

Příklad 1. dbx_connect() example

<?php $link = dbx_connect (DBX_ODBC, "", "db", "username", "password", DBX_PERSISTENT) or die ("Could not connect"); print ("Connected successfully"); dbx_close ($link); ?>

Poznámka: Always refer to the module-specific documentation as well.

dbx_error

(PHP 4 >= 4.0.6)

dbx_error -- Report the error message of the latest function call in the module (not just in the connection)

Description

string dbx_error ( object link_identifier)

dbx_error() returns a string containing the error message from the last function call of the abstracted module (e.g. mysql module). If there are multiple connections in the same module, just the last error is given. If there are connections on different modules, the latest error is returned for the module specified by the link_identifier parameter.

Příklad 1. dbx_error() example

<?php
$link   = dbx_connect(DBX_MYSQL, "localhost", "db", "username", "password")
    or die ("Could not connect");

$result = dbx_query($link, "select id from non_existing_table");
if ( $result == 0 ) {
    echo dbx_error ($link);
}
dbx_close ($link);
?>

Poznámka: Always refer to the module-specific documentation as well.

The error message for Microsoft SQL Server is actually the result of the mssql_get_last_message() function.

dbx_query

(PHP 4 >= 4.0.6)

dbx_query -- Send a query and fetch all results (if any)

Description

object dbx_query ( object link_identifier, string sql_statement [, long flags])

dbx_query() returns an object or 1 on success, and 0 on failure. The result object is returned only if the query given in sql_statement produces a result set.

Příklad 1. How to handle the returned value

<?php
$link   = dbx_connect(DBX_ODBC, "", "db", "username", "password")
    or die("Could not connect");

$result = dbx_query($link, 'SELECT id, parentid, description FROM table');

if ( is_object($result) ) {
    // ... do some stuff here, see detailed examples below ...
    // first, print out field names and types 
    // then, draw a table filled with the returned field values
}
else if ( $result == 1 ) {
    echo("Query executed successfully, but no result set returned");
}
else {
    exit("Query failed");
}

dbx_close($link);
?>

The flags parameter is used to control the amount of information that is returned. It may be any combination of the following constants with the bitwise OR operator (|):

DBX_RESULT_INDEX

It is always set, that is, the returned object has a data property which is a 2 dimensional array indexed numerically. For example, in the expression data[2][3] 2 stands for the row (or record) number and 3 stands for the column (or field) number. The first row and column are indexed at 0.

If DBX_RESULT_ASSOC is also specified, the returning object contains the information related to DBX_RESULT_INFO too, even if it was not specified.

DBX_RESULT_INFO

It provides info about columns, such as field names and field types.

DBX_RESULT_ASSOC

It effects that the field values can be accessed with the respective column names used as keys to the returned object's data property.

Associated results are actually references to the numerically indexed data, so modifying data[0][0] causes that data[0]['field_name_for_first_column'] is modified as well.

Note that DBX_RESULT_INDEX is always used, regardless of the actual value of flags parameter. This means that the following combinations is effective only:

DBX_RESULT_INDEX
DBX_RESULT_INDEX | DBX_RESULT_INFO
DBX_RESULT_INDEX | DBX_RESULT_INFO | DBX_RESULT_ASSOC - this is the default, if flags is not specified.

The returing object has four or five properties depending on flags:

handle

It is a valid handle for the connected database, and as such it can be used in module specific functions (if required).

$result = dbx_query ($link, "SELECT id FROM table");
mysql_field_len ($result->handle, 0);

cols and rows

These contain the number of columns (or fields) and rows (or records) respectively.

$result = dbx_query ($link, 'SELECT id FROM table');
echo $result->rows; // number of records
echo $result->cols; // number of fields

info (optional)

It is returned only if either DBX_RESULT_INFO or DBX_RESULT_ASSOC is specified in the flags parameter. It is a 2 dimensional array, that has two named rows (name and type) to retrieve column information.

Příklad 2. lists each field's name and type

$result = dbx_query ($link, 'SELECT id FROM table',
                     DBX_RESULT_INDEX | DBX_RESULT_INFO);

for ($i = 0; $i < $result->cols; $i++ ) {
    echo $result->info['name'][$i] . "\n";
    echo $result->info['type'][$i] . "\n";  
}

data

This property contains the actual resulting data, possibly associated with column names as well depending on flags. If DBX_RESULT_ASSOC is set, it is possible to use $result->data[2]["field_name"].

Příklad 3. outputs the content of data property into HTML table

$result = dbx_query ($link, 'SELECT id, parentid, description FROM table');

echo "<table>\n";
foreach ( $result->data as $row ) {
    echo "<tr>\n";
    foreach ( $row as $field ) {
        echo "<td>$field</td>";
    }
    echo "</tr>\n";
}
echo "</table>\n";

Poznámka: Always refer to the module-specific documentation as well.

dbx_sort

(PHP 4 >= 4.0.6)

dbx_sort -- Sort a result from a dbx_query by a custom sort function

Description

bool dbx_sort ( object result, string user_compare_function)

Vrací TRUE při úspěchu, FALSE při selhání.

Poznámka: It is always better to use ORDER BY SQL clause instead of dbx_sort(), if possible.

Příklad 1. dbx_sort() example

<?php
function user_re_order ($a, $b) {
    $rv = dbx_compare ($a, $b, "parentid", DBX_CMP_DESC);
    if ( !$rv ) {
        $rv = dbx_compare ($a, $b, "id", DBX_CMP_NUMBER);
    }
    return $rv;
}

$link   = dbx_connect (DBX_ODBC, "", "db", "username", "password")
    or die ("Could not connect");

$result = dbx_query ($link, "SELECT id, parentid, description FROM tbl ORDER BY id");
    // data in $result is now ordered by id

dbx_sort ($result, "user_re_order");
    // data in $result is now ordered by parentid (descending), then by id

dbx_close ($link);
?>

XXII. DB++ Functions

Varování

Tento modul je EXPERIMENTÁLNÍ. To znamená, že chování těchto funkcí a jejich názvy, přesněji řečeno COKOLI, co je zde zdokumentováno, se v budoucích verzích PHP může BEZ OHLÁŠENÍ změnit. Berte to v úvahu a používejte tento modul na vlastní nebezpečí.

Úvod

db++, made by the German company Concept asa, is a relational database system with high performance and low memory and disk usage in mind. While providing SQL as an additional language interface, it is not really a SQL database in the first place but provides its own AQL query language which is much more influenced by the relational algebra then SQL is.

Concept asa always had an interest in supporting open source languages, db++ has had Perl and Tcl call interfaces for years now and uses Tcl as its internal stored procedure language.

Požadavky

This extension relies on external client libraries so you have to have a db++ client installed on the system you want to use this extension on.

Concept asa provides db++ Demo versions and documentation for Linux, some other UNIX versions. There is also a Windows version of db++, but this extension doesn't support it (yet).

Instalace

In order to build this extension yourself you need the db++ client libraries and header files to be installed on your system (these are included in the db++ installation archives by default). You have to run configure with option --with-dbplus to build this extension.

configure looks for the client libraries and header files under the default paths /usr/dbplus, /usr/local/dbplus and /opt/dblus. If you have installed db++ in a different place you have add the installation path to the configure option like this: --with-dbplus=/your/installation/path.

Konfigurace běhu

Toto rozšíření nemá definováno žádné konfigurační direktivy.

Typy prostředků

dbplus_relation

Most db++ functions operate on or return dbplus_relation resources. A dbplus_relation is a handle to a stored relation or a relation generated as the result of a query.

Předdefinované konstanty

Tyto konstanty jsou definovány tímto rozšířením a budou k dispozici pouze tehdy, bylo-li rozšíření zkompilováno společně s PHP nebo dynamicky zavedeno za běhu.

db++ error codes

Tabulka 1. DB++ Error Codes

PHP Constant	db++ constant	meaning
`DBPLUS_ERR_NOERR` (integer)	ERR_NOERR	Null error condition
`DBPLUS_ERR_DUPLICATE` (integer)	ERR_DUPLICATE	Tried to insert a duplicate tuple
`DBPLUS_ERR_EOSCAN` (integer)	ERR_EOSCAN	End of scan from rget()
`DBPLUS_ERR_EMPTY` (integer)	ERR_EMPTY	Relation is empty (server)
`DBPLUS_ERR_CLOSE` (integer)	ERR_CLOSE	The server can't close
`DBPLUS_ERR_WLOCKED` (integer)	ERR_WLOCKED	The record is write locked
`DBPLUS_ERR_LOCKED` (integer)	ERR_LOCKED	Relation was already locked
`DBPLUS_ERR_NOLOCK` (integer)	ERR_NOLOCK	Relation cannot be locked
`DBPLUS_ERR_READ` (integer)	ERR_READ	Read error on relation
`DBPLUS_ERR_WRITE` (integer)	ERR_WRITE	Write error on relation
`DBPLUS_ERR_CREATE` (integer)	ERR_CREATE	Create() system call failed
`DBPLUS_ERR_LSEEK` (integer)	ERR_LSEEK	Lseek() system call failed
`DBPLUS_ERR_LENGTH` (integer)	ERR_LENGTH	Tuple exceeds maximum length
`DBPLUS_ERR_OPEN` (integer)	ERR_OPEN	Open() system call failed
`DBPLUS_ERR_WOPEN` (integer)	ERR_WOPEN	Relation already opened for writing
`DBPLUS_ERR_MAGIC` (integer)	ERR_MAGIC	File is not a relation
`DBPLUS_ERR_VERSION` (integer)	ERR_VERSION	File is a very old relation
`DBPLUS_ERR_PGSIZE` (integer)	ERR_PGSIZE	Relation uses a different page size
`DBPLUS_ERR_CRC` (integer)	ERR_CRC	Invalid crc in the superpage
`DBPLUS_ERR_PIPE` (integer)	ERR_PIPE	Piped relation requires lseek()
`DBPLUS_ERR_NIDX` (integer)	ERR_NIDX	Too many secondary indices
`DBPLUS_ERR_MALLOC` (integer)	ERR_MALLOC	Malloc() call failed
`DBPLUS_ERR_NUSERS` (integer)	ERR_NUSERS	Error use of max users
`DBPLUS_ERR_PREEXIT` (integer)	ERR_PREEXIT	Caused by invalid usage
`DBPLUS_ERR_ONTRAP` (integer)	ERR_ONTRAP	Caused by a signal
`DBPLUS_ERR_PREPROC` (integer)	ERR_PREPROC	Error in the preprocessor
`DBPLUS_ERR_DBPARSE` (integer)	ERR_DBPARSE	Error in the parser
`DBPLUS_ERR_DBRUNERR` (integer)	ERR_DBRUNERR	Run error in db
`DBPLUS_ERR_DBPREEXIT` (integer)	ERR_DBPREEXIT	Exit condition caused by prexit() * procedure
`DBPLUS_ERR_WAIT` (integer)	ERR_WAIT	Wait a little (Simple only)
`DBPLUS_ERR_CORRUPT_TUPLE` (integer)	ERR_CORRUPT_TUPLE	A client sent a corrupt tuple
`DBPLUS_ERR_WARNING0` (integer)	ERR_WARNING0	The Simple routines encountered a non fatal error which was corrected
`DBPLUS_ERR_PANIC` (integer)	ERR_PANIC	The server should not really die but after a disaster send ERR_PANIC to all its clients
`DBPLUS_ERR_FIFO` (integer)	ERR_FIFO	Can't create a fifo
`DBPLUS_ERR_PERM` (integer)	ERR_PERM	Permission denied
`DBPLUS_ERR_TCL` (integer)	ERR_TCL	TCL_error
`DBPLUS_ERR_RESTRICTED` (integer)	ERR_RESTRICTED	Only two users
`DBPLUS_ERR_USER` (integer)	ERR_USER	An error in the use of the library by an application programmer
`DBPLUS_ERR_UNKNOWN` (integer)	ERR_UNKNOWN

Obsah
dbplus_add -- Add a tuple to a relation
dbplus_aql -- Perform AQL query
dbplus_chdir -- Get/Set database virtual current directory
dbplus_close -- Close a relation
dbplus_curr -- Get current tuple from relation
dbplus_errcode -- Get error string for given errorcode or last error
dbplus_errno -- Get error code for last operation
dbplus_find -- Set a constraint on a relation
dbplus_first -- Get first tuple from relation
dbplus_flush -- Flush all changes made on a relation
dbplus_freealllocks -- Free all locks held by this client
dbplus_freelock -- Release write lock on tuple
dbplus_freerlocks -- Free all tuple locks on given relation
dbplus_getlock -- Get a write lock on a tuple
dbplus_getunique -- Get a id number unique to a relation
dbplus_info -- ???
dbplus_last -- Get last tuple from relation
dbplus_lockrel -- Request write lock on relation
dbplus_next -- Get next tuple from relation
dbplus_open -- Open relation file
dbplus_prev -- Get previous tuple from relation
dbplus_rchperm -- Change relation permissions
dbplus_rcreate -- Creates a new DB++ relation
dbplus_rcrtexact -- Creates an exact but empty copy of a relation including indices
dbplus_rcrtlike -- Creates an empty copy of a relation with default indices
dbplus_resolve -- Resolve host information for relation
dbplus_restorepos -- ???
dbplus_rkeys -- Specify new primary key for a relation
dbplus_ropen -- Open relation file local
dbplus_rquery -- Perform local (raw) AQL query
dbplus_rrename -- Rename a relation
dbplus_rsecindex -- Create a new secondary index for a relation
dbplus_runlink -- Remove relation from filesystem
dbplus_rzap -- Remove all tuples from relation
dbplus_savepos -- ???
dbplus_setindex -- ???
dbplus_setindexbynumber -- ???
dbplus_sql -- Perform SQL query
dbplus_tcl -- Execute TCL code on server side
dbplus_tremove -- Remove tuple and return new current tuple
dbplus_undo -- ???
dbplus_undoprepare -- ???
dbplus_unlockrel -- Give up write lock on relation
dbplus_unselect -- Remove a constraint from relation
dbplus_update -- Update specified tuple in relation
dbplus_xlockrel -- Request exclusive lock on relation
dbplus_xunlockrel -- Free exclusive lock on relation

dbplus_add

(4.1.0 - 4.2.1 only)

dbplus_add -- Add a tuple to a relation

Description

int dbplus_add ( resource relation, array tuple)

Varování

This function will add a tuple to a relation. The tuple data is an array of attribute/value pairs to be inserted into the given relation. After successful execution the tuple array will contain the complete data of the newly created tuple, including all implicitly set domain fields like sequences.

The function will return zero (aka. DBPLUS_ERR_NOERR) on success or a db++ error code on failure. See dbplus_errcode() or the introduction to this chapter for more information on db++ error codes.

dbplus_aql

(4.1.0 - 4.2.1 only)

dbplus_aql -- Perform AQL query

Description

resource dbplus_aql ( string query [, string server [, string dbpath]])

Varování

resource dbplus_open ( string name)

resource dbplus_rcreate ( string name, mixed domlist [, boolean overwrite])

resource dbplus_rkeys ( resource relation, mixed domlist)

resource dbplus_rsecindex ( resource relation, mixed domlist, int type)

int dbplus_tcl ( int sid, string script)

Tyto funkce jsou k dispozici jako součást standardního modulu, který je vždy dostupný.

Installation

To get these functions to work, you have to configure PHP with --enable-dio.

Konfigurace běhu

Toto rozšíření nemá definováno žádné konfigurační direktivy.

Typy prostředků

One resource type is defined by this extension: a file descriptor returnded by dio_open().

Předdefinované konstanty

Toto rozšíření nemá definovány žádné konstanty.

Obsah
dio_close -- Closes the file descriptor given by fd
dio_fcntl -- Performs a c library fcntl on fd
dio_open -- Opens a new filename with specified permissions of flags and creation permissions of mode
dio_read -- Reads n bytes from fd and returns them, if n is not specified, reads 1k block
dio_seek -- Seeks to pos on fd from whence
dio_stat -- Gets stat information about the file descriptor fd
dio_truncate -- Truncates file descriptor fd to offset bytes
dio_write -- Writes data to fd with optional truncation at length

dio_close

(PHP 4 >= 4.2.0)

dio_close -- Closes the file descriptor given by fd

Description

void dio_close ( resource fd)

The function dio_close() closes the file descriptor resource.

dio_fcntl

(PHP 4 >= 4.2.0)

dio_fcntl -- Performs a c library fcntl on fd

Description

mixed dio_fcntl ( resource fd, int cmd [, mixed arg])

The dio_fcntl() function performs the operation specified by cmd on the file descriptor fd. Some commands require additional arguments args to be supplied.

arg is an associative array, when cmd is F_SETLK or F_SETLLW, with the following keys:

"start" - offset where lock begins
"length" - size of locked area. zero means to end of file
"wenth" - Where l_start is relative to: can be SEEK_SET, SEEK_END and SEEK_CUR
"type" - type of lock: can be F_RDLCK (read lock), F_WRLCK (write lock) or F_UNLCK (unlock)

cmd can be one of the following operations:

F_SETLK - Lock is set or cleared. If the lock is held by someone else dio_fcntl() returns -1.
F_SETLKW - like F_SETLK, but in case the lock is held by someone else, dio_fcntl() waits until the lock is released.
F_GETLK - dio_fcntl() returns an associative array (as described above) if someone else prevents lock. If there is no obstruction key "type" will set to F_UNLCK.
F_DUPFD - finds the lowest numbered available file descriptor greater or equal than arg and returns them.

dio_open

(PHP 4 >= 4.2.0)

dio_open -- Opens a new filename with specified permissions of flags and creation permissions of mode

Description

resource dio_open ( string filename, int flags [, int mode])

dio_open() opens a file and returns a new file descriptor for it, or -1 if any error occurred. If flags is O_CREAT, optional third parameter mode will set the mode of the file (creation permissions). The flags parameter can be one of the following options:

O_RDONLY - opens the file for read access
O_WRONLY - opens the file for write access
O_RDWR - opens the file for both reading and writing

The flags parameter can also include any combination of the following flags:

O_CREAT - creates the file, if it doesn't already exist
O_EXCL - if both, O_CREAT and O_EXCL are set, dio_open() fails, if file already exists
O_TRUNC - if file exists, and its opened for write access, file will be truncated to zero length.
O_APPEND - write operations write data at the end of file
O_NONBLOCK - sets non blocking mode

dio_read

(PHP 4 >= 4.2.0)

dio_read -- Reads n bytes from fd and returns them, if n is not specified, reads 1k block

Description

string dio_read ( resource fd [, int n])

The function dio_read() reads and returns n bytes from file with descriptor resource. If n is not specified, dio_read() reads 1K sized block and returns them.

dio_seek

(PHP 4 >= 4.2.0)

dio_seek -- Seeks to pos on fd from whence

Description

int dio_seek ( resource fd, int pos, int whence)

The function dio_seek() is used to change the file position of the file with descriptor resource. The parameter whence specifies how the position pos should be interpreted:

SEEK_SET - specifies that pos is specified from the beginning of the file
SEEK_CUR - Specifies that pos is a count of characters from the current file position. This count may be positive or negative
SEEK_END - Specifies that pos is a count of characters from the end of the file. A negative count specifies a position within the current extent of the file; a positive count specifies a position past the current end. If you set the position past the current end, and actually write data, you will extend the file with zeros up to that position

dio_stat

(PHP 4 >= 4.2.0)

dio_stat -- Gets stat information about the file descriptor fd

Description

array dio_stat ( resource fd)

Function dio_stat() returns information about the file with file descriptor fd. dio_stat() returns an associative array with the following keys:

"device" - device
"inode" - inode
"mode" - mode
"nlink" - number of hard links
"uid" - user id
"gid" - group id
"device_type" - device type (if inode device)
"size" - total size in bytes
"blocksize" - blocksize
"blocks" - number of blocks allocated
"atime" - time of last access
"mtime" - time of last modification
"ctime" - time of last change

On error dio_stat() returns NULL.

dio_truncate

(PHP 4 >= 4.2.0)

dio_truncate -- Truncates file descriptor fd to offset bytes

Description

bool dio_truncate ( resource fd, int offset)

Function dio_truncate() causes the file referenced by fd to be truncated to at most offset bytes in size. If the file previously was larger than this size, the extra data is lost. If the file previously was shorter, it is unspecified whether the file is left unchanged or is extended. In the latter case the extended part reads as zero bytes. Returns 0 on success, otherwise -1.

dio_write

(PHP 4 >= 4.2.0)

dio_write -- Writes data to fd with optional truncation at length

Description

int dio_write ( resource fd, string data [, int len])

The function dio_write() writes up to len bytes from data to file fd. If len is not specified, dio_write() writes all data to the specified file. dio_write() returns the number of bytes written to fd.

XXIV. Adresářové funkce

Obsah
chdir -- change directory
chroot -- change the root directory
dir -- directory class
closedir -- Zavírá otevřený adresář
getcwd -- Získává aktuální pracovní adresář
opendir -- Otevře adresář
readdir -- Přečte položku z deskriptoru adresáře
rewinddir -- návrat na začátek adresáře

chdir

(PHP 3, PHP 4 )

chdir -- change directory

Popis

int chdir ( string directory)

Mění aktuální adresář PHP na directory. Pokud se nepodařilo změnít adresář, vrací FALSE, jinak TRUE.

chroot

(PHP 4 >= 4.0.5)

chroot -- change the root directory

Description

bool chroot ( string directory)

Changes the root directory of the current process to directory. Returns FALSE if unable to change the root directory, TRUE otherwise.

Poznámka: It's not wise to use this function when running in a webserver environment, because it's not possible to reset the root directory to / again at the end of the request. This function will only function correct when running as CGI this way.

Všimněte si, že readdir() vrací také . a .. položky (odkaz na sebe sama a na nadřazený adresář. Pokud je nechcete, můžete je snadno vynechat:

Příklad 2. Vypiš všechny soubory v adresáři a vynech . a ..

<?php $handle=opendir('.'); while (false!==($file = readdir($handle))) { if ($file != "." && $file != "..") { echo "$file\n"; } } closedir($handle); ?>

rewinddir

(PHP 3, PHP 4 )

rewinddir -- návrat na začátek adresáře

Popis

void rewinddir ( int dir_handle)

Vrací adresářový proud odkazovaný deskriptorem dir_handle na začátek adresáře.

XXV. DOM XML funkce

Varování

Tyto funkce jsou přístupné pouze pokud bylo PHP zkonfigurováno s volbou --with-dom=[DIR], s využitím GNOME xml knihovny. Je potřeba nejméně libxml-2.0.0 (ne betaverze). Tyto funkce byly přidány v PHP 4.

Tento modul definuje následující konstanty:

Tabulka 1. XML konstanty

Konstanta	Hodnota	Popis
XML_ELEMENT_NODE	1
XML_ATTRIBUTE_NODE	2
XML_TEXT_NODE	3
XML_CDATA_SECTION_NODE	4
XML_ENTITY_REF_NODE	5
XML_ENTITY_NODE	6
XML_PI_NODE	7
XML_COMMENT_NODE	8
XML_DOCUMENT_NODE	9
XML_DOCUMENT_TYPE_NODE	10
XML_DOCUMENT_FRAG_NODE	11
XML_NOTATION_NODE	12
XML_GLOBAL_NAMESPACE	1
XML_LOCAL_NAMESPACE	2

Tento modul definuje několik tříd. DOM XML funkce vrací rozparsovaný strom XML dokumentu, kde každý uzel je objektem patrícím do jedné z těchto tříd.

Obsah
DomAttribute->name -- Returns name of attribute
DomAttribute->specified -- Checks if attribute is specified
DomAttribute->value -- Returns value of attribute
DomDocument->add_root [deprecated] -- Adds a root node
DomDocument->create_attribute -- Create new attribute
DomDocument->create_cdata_section -- Create new cdata node
DomDocument->create_comment -- Create new comment node
DomDocument->create_element -- Create new element node
DomDocument->create_entity_reference --
DomDocument->create_processing_instruction -- Creates new PI node
DomDocument->create_text_node -- Create new text node
DomDocument->doctype -- Returns the document type
DomDocument->document_element -- Returns root element node
DomDocument->dump_file -- Dumps the internal XML tree back into a file
DomDocument->dump_mem -- Dumps the internal XML tree back into a string
DomDocument->get_element_by_id -- Searches for an element with a certain id
DomDocument->get_elements_by_tagname --
DomDocument->html_dump_mem -- Dumps the internal XML tree back into a string as HTML
DomDocumentType->entities -- Returns list of entities
DomDocumentType->internal_subset -- Returns internal subset
DomDocumentType->name -- Returns name of document type
DomDocumentType->notations -- Returns list of notations
DomDocumentType->public_id -- Returns public id of document type
DomDocumentType->system_id -- Returns system id of document type
DomElement->get_attribute_node -- Returns value of attribute
DomElement->get_attribute -- Returns value of attribute
DomElement->get_elements_by_tagname -- Adds new attribute
DomElement->has_attribute -- Adds new attribute
DomElement->remove_attribute -- Adds new attribute
DomElement->set_attribute -- Adds new attribute
DomElement->tagname -- Returns name of element
DomNode->append_child -- Adds new child at the end of the children
DomNode->append_sibling -- Adds new sibling to a node
DomNode->attributes -- Returns list of attributes
DomNode->child_nodes -- Returns children of node
DomNode->clone_node -- Clones a node
DomNode->dump_node -- Dumps a single node
DomNode->first_child -- Returns first child of node
DomNode->get_content -- Gets content of node
DomNode->has_attributess -- Checks if node has attributes
DomNode->has_child_nodes -- Checks if node has children
DomNode->insert_before -- Inserts new node as child
DomNode->is_blank_node -- Checks if node is blank
DomNode->last_child -- Returns last child of node
DomNode->next_sibling -- Returns the next sibling of node
DomNode->node_name -- Returns name of node
DomNode->node_type -- Returns type of node
DomNode->node_value -- Returns value of a node
DomNode->owner_document -- Returns the document this node belongs to
DomNode->parent_node -- Returns the parent of the node
DomNode->prefix -- Returns name space prefix of node
DomNode->previous_sibling -- Returns the previous sibling of node
DomNode->remove_child -- Removes child from list of children
DomNode->replace_child -- Replaces a child
DomNode->replace_node -- Replaces node
DomNode->set_content -- Sets content of node
DomNode->set_name -- Sets name of node
DomNode->unlink_node -- Deletes node
DomProcessingInstruction->data -- Returns data of pi node
DomProcessingInstruction->target -- Returns target of pi node
domxml_new_doc -- Creates new empty XML document
domxml_open_file -- Creates a DOM object from XML file
domxml_open_mem -- Creates a DOM object of an XML document
domxml_version -- Get XML library version
domxml_xmltree -- Creates a tree of PHP objects from an XML document
xpath_eval_expression -- Evaluates the XPath Location Path in the given string
xpath_eval -- Evaluates the XPath Location Path in the given string
xpath_new_context -- Creates new xpath context
xptr_eval -- Evaluate the XPtr Location Path in the given string
xptr_new_context -- Create new XPath Context

The return value is false if an error occured.

DomDocument->create_element

(unknown)

DomDocument->create_element -- Create new element node

Description

object DomDocument->create_element ( string name)

This function returns a new instance of class DomElement. The tag name of the element is the value of the passed parameter. This node will not show up in the document unless it is inserted with e.g. DomNode_append_child().

The return value is false if an error occured.

See also DomNode_append_child(), DomDocument_create_text(), DomDocument_create_comment(), DomDocument_create_attribute(), DomDocument_create_processing_instruction(), DomDocument_create_entity_reference(), DomNode_insert_before().

DomDocument->create_entity_reference

(unknown)

DomDocument->create_entity_reference --

string DomDocument->dump_file ( string filename [, bool compressionmode [, bool format]])

Creates an XML document from the dom representation. This function usually is called after building a new dom document from scratch as in the example below. The format specifies whether the output should be neatly formatted, or not. The first parameter specifies the name of the filename and the second parameter, whether it should be compressed or not.

Příklad 1. Creating a simple HTML document header

<?php $doc = domxml_new_doc("1.0"); $root = $doc->create_element("HTML"); $root = $doc->append_child($root); $head = $doc->create_element("HEAD"); $head = $root->append_child($head); $title = $doc->create_element("TITLE"); $title = $head->append_child($title); $text = $doc->create_text_node("This is the title"); $text = $title->append_child($text); $doc->dump_file("/tmp/test.xml", false, true); ?>

See also DomDocument_dump_mem() DomDocument_html_dump_mem().

DomDocument->dump_mem

(unknown)

DomDocument->dump_mem -- Dumps the internal XML tree back into a string

Description

string DomDocument->dump_mem ( [bool format])

Varování

Poznámka: The first parameter was added in PHP 4.3.0.

See also DomDocument_dump_file(), DomDocument_html_dump_mem().

DomDocument->get_element_by_id

(unknown)

DomDocument->get_element_by_id -- Searches for an element with a certain id

Description

object DomDocument->get_element_by_id ( string id)

This function is similar to DomDocument_get_elements_by_tagname() but searches for an element with a given id. According to the DOM standard this requires a DTD which defines the attribute ID to be of type ID, though the current implementation simply does an xpath search for "//*[@ID = '%s']". This does not comply to the DOM standard which requires to return null if it is not known which attribute is of type id. This behaviour is likely to be fixed, so do not rely on the current behaviour.

See also DomDocument_get_elements_by_tagname()

DomDocument->get_elements_by_tagname

(unknown)

This functions appends a child to an existing list of children or creates a new list of children. The child can be created with e.g. DomDocument_create_element(), DomDocument_create_text() etc. or simply by using any other node.

Before a new child is appended it is first duplicated. Therefore the new child is a completely new copy which can be modified without changing the node which was passed to this function. If the node passed has children itself, they will be duplicated as well, which makes it quite easy to duplicate large parts of a xml document. The return value is the appended child. If you plan to do further modifications on the appended child you must use the returned node.

The following example will add a new element node to a fresh document and sets the attribute "align" to "left".

Příklad 1. Adding a child

<?php $doc = domxml_new_doc("1.0"); $node = $doc->create_element("para"); $newnode = $doc->append_child($node); $newnode->set_attribute("align", "left"); ?>
The above example could also be written as the following:

Příklad 2. Adding a child

<?php $doc = domxml_new_doc("1.0"); $node = $doc->create_element("para"); $node->set_attribute("align", "left"); $newnode = $doc->append_child($node); ?>
A more comples example is the one below. It first searches for a certain element, duplicates it including its children and adds it as a sibling. Finally a new attribute is added to one of the children of the new sibling and the whole document is dumped.

Příklad 3. Adding a child

<?php include("example.inc"); if(!$dom = domxml_open_mem($xmlstr)) { echo "Error while parsing the document\n"; exit; } $elements = $dom->get_elements_by_tagname("informaltable"); print_r($elements); $element = $elements[0]; $parent = $element->parent_node(); $newnode = $parent->append_child($element); $children = $newnode->children(); $attr = $children[1]->set_attribute("align", "left"); echo "<PRE>"; $xmlfile = $dom->dump_mem(); echo htmlentities($xmlfile); echo "</PRE>"; ?>
The above example could also be done with DomNode_insert_before() instead of DomNode_append_child().

DomNode->append_sibling

(unknown)

DomNode->append_sibling -- Adds new sibling to a node

Description

object DomNode->append_sibling ( object newnode)

This functions appends a sibling to an existing node. The child can be created with e.g. DomDocument_create_element(), DomDocument_create_text() etc. or simply by using any other node.

Before a new sibling is added it is first duplicated. Therefore the new child is a completely new copy which can be modified without changing the node which was passed to this function. If the node passed has children itself, they will be duplicated as well, which makes it quite easy to duplicate large parts of a xml document. The return value is the added sibling. If you plan to do further modifications on the added sibling you must use the returned node.

This function has been added to provide the behaviour of DomNode_append_child() as it works till PHP 4.2.

DomNode->attributes

(unknown)

DomNode->attributes -- Returns list of attributes

bool DomNode->has_attributes ( void)

This function checks if the node has attributes.

DomNode->has_child_nodes

(unknown)

DomNode->has_child_nodes -- Checks if node has children

Description

bool DomNode->has_child_nodes ( void)

This function checks if the node has children.

DomNode->insert_before

(unknown)

DomNode->insert_before -- Inserts new node as child

Description

object DomNode->insert_before ( object newnode, object refnode)

object DomNode->next_sibling ( void)

This function returns the next sibling of the current node. If there is no next sibling it returns false. You can use this function to iterate over all children of a node as shown in the example.

Příklad 1. Iterate over children

<?php include("example.inc"); if(!$dom = domxml_open_mem($xmlstr)) { echo "Error while parsing the document\n"; exit; } $elements = $dom->get_elements_by_tagname("tbody"); $element = $elements[0]; $child = $element->first_child(); while($child) { print_r($child); $child = $child->next_sibling(); } ?>

See also DomNode_previous_sibling().

DomNode->node_name

(unknown)

DomNode->node_name -- Returns name of node

Description

string DomNode->node_name ( void)

Returns name of the node. The name has different meanings for the different types of nodes as illustrated in the following table.

Tabulka 1. Meaning of value

Type	Meaning
DomAttribute	value of attribute
DomAttribute
DomCDataSection	#cdata-section
DomComment	#comment
DomDocument	#document
DomDocumentType	document type name
DomElement	tag name
DomEntity	name of entity
DomEntityReference	name of entity reference
DomNotation	notation name
DomProcessingInstruction	target
DomText	#text

DomNode->node_type

(unknown)

DomNode->node_type -- Returns type of node

Description

int DomNode->node_type ( void)

Returns the type of the node. All possible types are listed in the table in the introduction.

DomNode->node_value

(unknown)

DomNode->node_value -- Returns value of a node

Description

string DomNode->node_value ( void)

Returns value of the node. The value has different meanings for the different types of nodes as illustrated in the following table.

Tabulka 1. Meaning of value

Type	Meaning
DomAttribute	value of attribute
DomAttribute
DomCDataSection	content
DomComment	content of comment
DomDocument	null
DomDocumentType	null
DomElement	null
DomEntity	null
DomEntityReference	null
DomNotation	null
DomProcessingInstruction	entire content without target
DomText	content of text

DomNode->owner_document

(unknown)

DomNode->owner_document -- Returns the document this node belongs to

Description

object DomNode->owner_document ( void)

This function returns the document the current node belongs to.

The following example will create two identical lists of children.

Příklad 1. Finding the document of a node

<?php $doc = domxml_new_doc("1.0"); $node = $doc->create_element("para"); $node = $doc->append_child($node); $children = $doc->children(); print_r($children); $doc2 = $node->owner_document(); $children = $doc2->children(); print_r($children); ?>

DomNode->parent_node

(unknown)

DomNode->parent_node -- Returns the parent of the node

Description

object DomNode->parent_node ( void)

object DomNode->remove_child ( object oldchild)

bool DomNode->set_content ( void)

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

DomNode->set_name

(unknown)

DomNode->set_name -- Sets name of node

string domxml_version ( void)

This function returns the version of the XML library version currently used.

domxml_xmltree

(PHP 4 >= 4.2.1)

domxml_xmltree -- Creates a tree of PHP objects from an XML document

Description

object domxml_xmltree ( string str)

int xptr_eval ( [object xpath_context, string eval_str])

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

xptr_new_context

(PHP 4 >= 4.0.4)

xptr_new_context -- Create new XPath Context

Description

string xptr_new_context ( [object doc_handle])

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

XXVI. .NET functions

Úvod

Varování

Obsah
dotnet_load -- Loads a DOTNET module

dotnet_load

(unknown)

dotnet_load -- Loads a DOTNET module

Description

int dotnet_load ( string assembly_name [, string datatype_name [, int codepage]])

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

XXVII. Error Handling and Logging Functions

Úvod

These are functions dealing with error handling and logging. They allow you to define your own error handling rules, as well as modify the way the errors can be logged. This allows you to change and enhance error reporting to suit your needs.

With the logging functions, you can send messages directly to other machines, to an email (or email to pager gateway!), to system logs, etc., so you can selectively log and monitor the most important parts of your applications and websites.

The error reporting functions allow you to customize what level and kind of error feedback is given, ranging from simple notices to customized functions returned during errors.

Požadavky

Tyto funkce jsou k dispozici jako součást standardního modulu, který je vždy dostupný.

Instalace

K používání těchto funkcí není třeba žádná instalace, jsou součástí jádra PHP.

Předdefinované konstanty

These constants are part of the PHP core and always available. You may use these constant names in php.ini but not outside of PHP, like in httpd.conf, where you'd use the bitmask values instead.

Tabulka 1. Errors and Logging

Value	Constant	Description
1	`E_ERROR` (integer)	Fatal run-time errors. These indicate errors that can not be recovered from, such as a memory allocation problem. Execution of the script is halted.
2	`E_WARNING` (integer)	Run-time warnings (non-fatal errors). Execution of the script is not halted.
4	`E_PARSE` (integer)	Compile-time parse errors. Parse errors should only be generated by the parser.
8	`E_NOTICE` (integer)	Run-time notices. Indicate that the script encountered something that could indicate an error, but could also happen in the normal course of running a script.
16	`E_CORE_ERROR` (integer)	Fatal errors that occur during PHP's initial startup. This is like an `E_ERROR`, except it is generated by the core of PHP.
32	`E_CORE_WARNING` (integer)	Warnings (non-fatal errors) that occur during PHP's initial startup. This is like an `E_WARNING`, except it is generated by the core of PHP. PHP 4 only.
64	`E_COMPILE_ERROR` (integer)	Fatal compile-time errors. This is like an `E_ERROR`, except it is generated by the Zend Scripting Engine. PHP 4 only.
128	`E_COMPILE_WARNING` (integer)	Compile-time warnings (non-fatal errors). This is like an `E_WARNING`, except it is generated by the Zend Scripting Engine. PHP 4 only.
256	`E_USER_ERROR` (integer)	User-generated error message. This is like an `E_ERROR`, except it is generated in PHP code by using the PHP function trigger_error(). PHP 4 only.
512	`E_USER_WARNING` (integer)	User-generated warning message. This is like an `E_WARNING`, except it is generated in PHP code by using the PHP function trigger_error(). PHP 4 only.
1024	`E_USER_NOTICE` (integer)	User-generated notice message. This is like an `E_NOTICE`, except it is generated in PHP code by using the PHP function trigger_error(). PHP 4 only.
2047	`E_ALL` (integer)	All errors and warnings, as supported.

Viz také

Fore more Information see the section Error Handling.

Obsah
error_log -- send an error message somewhere
error_reporting -- set which PHP errors are reported
restore_error_handler -- Restores the previous error handler function
set_error_handler -- Sets a user-defined error handler function.
trigger_error -- Generates a user-level error/warning/notice message
user_error -- Generates a user-level error/warning/notice message

error_log

(PHP 3, PHP 4 )

error_log -- send an error message somewhere

Description

int error_log ( string message [, int message_type [, string destination [, string extra_headers]]])

Sends an error message to the web server's error log, a TCP port or to a file. The first parameter, message, is the error message that should be logged. The second parameter, message_type says where the message should go:

Tabulka 1. error_log() log types

0	`message` is sent to PHP's system logger, using the Operating System's system logging mechanism or a file, depending on what the error_log configuration directive is set to.
1	`message` is sent by email to the address in the `destination` parameter. This is the only message type where the fourth parameter, `extra_headers` is used. This message type uses the same internal function as mail() does.
2	`message` is sent through the PHP debugging connection. This option is only available if remote debugging has been enabled. In this case, the `destination` parameter specifies the host name or IP address and optionally, port number, of the socket receiving the debug information.
3	`message` is appended to the file `destination`.

Varování

Remote debugging via TCP/IP is a PHP 3 feature that is not available in PHP 4.

Příklad 1. error_log() examples

// Send notification through the server log if we can not // connect to the database. if (!Ora_Logon ($username, $password)) { error_log ("Oracle database not available!", 0); } // Notify administrator by email if we run out of FOO if (!($foo = allocate_new_foo()) { error_log ("Big trouble, we're all out of FOOs!", 1, "operator@mydomain.com"); } // other ways of calling error_log(): error_log ("You messed up!", 2, "127.0.0.1:7000"); error_log ("You messed up!", 2, "loghost"); error_log ("You messed up!", 3, "/var/tmp/my-errors.log");

error_reporting

(PHP 3, PHP 4 )

error_reporting -- set which PHP errors are reported

Description

int error_reporting ( [int level])

The error_reporting() function sets the error_reporting directive at runtime. PHP has many levels of errors, using this function sets that level for the duration (runtime) of your script.

error_reporting() sets PHP's error reporting level, and returns the old level. The level parameter takes on either a bitmask, or named constants. Using named constants is strongly encouraged to ensure compatibility for future versions. As error levels are added, the range of integers increases, so older integer-based error levels will not always behave as expected.

Some example uses:

Příklad 1. error_reporting() examples

<?php // Turn off all error reporting error_reporting(0); // Report simple running errors error_reporting (E_ERROR | E_WARNING | E_PARSE); // Reporting E_NOTICE can be good too (to report uninitialized // variables or catch variable name misspellings ...) error_reporting (E_ERROR | E_WARNING | E_PARSE | E_NOTICE); // Report all errors except E_NOTICE // This is the default value set in php.ini error_reporting (E_ALL ^ E_NOTICE); // Report all PHP errors (bitwise 63 may be used in PHP 3) error_reporting (E_ALL); // Same as error_reporting(E_ALL); ini_set ('error_reporting', E_ALL); ?>

The available error level constants are listed below. The actual meanings of these error levels are described in the error handling section of the manual.

Tabulka 1. error_reporting() level constants and bit values

value	constant
1	E_ERROR
2	E_WARNING
4	E_PARSE
8	E_NOTICE
16	E_CORE_ERROR
32	E_CORE_WARNING
64	E_COMPILE_ERROR
128	E_COMPILE_WARNING
256	E_USER_ERROR
512	E_USER_WARNING
1024	E_USER_NOTICE
2047	E_ALL

See also the display_errors directive and ini_set().

restore_error_handler

(PHP 4 >= 4.0.1)

restore_error_handler -- Restores the previous error handler function

Description

void restore_error_handler ( void)

Used after changing the error handler function using set_error_handler(), to revert to the previous error handler (which could be the built-in or a user defined function)

set_error_handler

(PHP 4 >= 4.0.1)

set_error_handler -- Sets a user-defined error handler function.

Description

string set_error_handler ( string error_handler)

Sets a user function (error_handler) to handle errors in a script. Returns the previously defined error handler (if any), or FALSE on error. This function can be used for defining your own way of handling errors during runtime, for example in applications in which you need to do cleanup of data/files when a critical error happens, or when you need to trigger an error under certain conditions (using trigger_error())

The user function needs to accept 2 parameters: the error code, and a string describing the error. From PHP 4.0.2, an additional 3 optional parameters are supplied: the filename in which the error occurred, the line number in which the error occurred, and the context in which the error occurred (an array that points to the active symbol table at the point the error occurred).

Poznámka: The following error types cannot be handled with a user defined function: E_ERROR, E_PARSE, E_CORE_ERROR, E_CORE_WARNING, E_COMPILE_ERROR and E_COMPILE_WARNING.

The example below shows the handling of internal exceptions by triggering errors and handling them with a user defined function:

Příklad 1. Error handling with set_error_handler() and trigger_error()

<?php // redefine the user error constants - PHP 4 only define (FATAL,E_USER_ERROR); define (ERROR,E_USER_WARNING); define (WARNING,E_USER_NOTICE); // set the error reporting level for this script error_reporting (FATAL | ERROR | WARNING); // error handler function function myErrorHandler ($errno, $errstr, $errfile, $errline) { switch ($errno) { case FATAL: echo "<b>FATAL</b> [$errno] $errstr<br>\n"; echo " Fatal error in line ".$errline." of file ".$errfile; echo ", PHP ".PHP_VERSION." (".PHP_OS.")<br>\n"; echo "Aborting...<br>\n"; exit 1; break; case ERROR: echo "<b>ERROR</b> [$errno] $errstr<br>\n"; break; case WARNING: echo "<b>WARNING</b> [$errno] $errstr<br>\n"; break; default: echo "Unkown error type: [$errno] $errstr<br>\n"; break; } } // function to test the error handling function scale_by_log ($vect, $scale) { if ( !is_numeric($scale) || $scale <= 0 ) trigger_error("log(x) for x <= 0 is undefined, you used: scale = $scale", FATAL); if (!is_array($vect)) { trigger_error("Incorrect input vector, array of values expected", ERROR); return null; } for ($i=0; $i<count($vect); $i++) { if (!is_numeric($vect[$i])) trigger_error("Value at position $i is not a number, using 0 (zero)", WARNING); $temp[$i] = log($scale) * $vect[$i]; } return $temp; } // set to the user defined error handler $old_error_handler = set_error_handler("myErrorHandler"); // trigger some errors, first define a mixed array with a non-numeric item echo "vector a\n"; $a = array(2,3,"foo",5.5,43.3,21.11); print_r($a); // now generate second array, generating a warning echo "----\nvector b - a warning (b = log(PI) * a)\n"; $b = scale_by_log($a, M_PI); print_r($b); // this is trouble, we pass a string instead of an array echo "----\nvector c - an error\n"; $c = scale_by_log("not array",2.3); var_dump($c); // this is a critical error, log of zero or negative number is undefined echo "----\nvector d - fatal error\n"; $d = scale_by_log($a, -2.5); ?>
And when you run this sample script, the output will be

vector a
Array
(
    [0] => 2
    [1] => 3
    [2] => foo
    [3] => 5.5
    [4] => 43.3
    [5] => 21.11
)
----
vector b - a warning (b = log(PI) * a)
<b>WARNING</b> [1024] Value at position 2 is not a number, using 0 (zero)<br>
Array
(
    [0] => 2.2894597716988
    [1] => 3.4341896575482
    [2] => 0
    [3] => 6.2960143721717
    [4] => 49.566804057279
    [5] => 24.165247890281
)
----
vector c - an error
<b>ERROR</b> [512] Incorrect input vector, array of values expected<br>
NULL
----
vector d - fatal error
<b>FATAL</b> [256] log(x) for x <= 0 is undefined, you used: scale = -2.5<br>
  Fatal error in line 36 of file trigger_error.php, PHP 4.0.2 (Linux)<br>
Aborting...<br>

It is important to remember that the standard PHP error handler is completely bypassed. error_reporting() settings will have no effect and your error handler will be called regardless - however you are still able to read the current value of error_reporting and act appropriately. Of particular note is that this value will be 0 if the statement that caused the error was prepended by the @ error-control operator.

Also note that it is your responsibility to die() if necessary. If the error-handler function returns, script execution will continue with the next statement after the one that caused an error.

Poznámka: If errors occur before the script is executed (e.g. on file uploads) the custom error handler cannot be called since it is not registered at that time.

trigger_error

(PHP 4 >= 4.0.1)

trigger_error -- Generates a user-level error/warning/notice message

Description

void trigger_error ( string error_msg [, int error_type])

Used to trigger a user error condition, it can be used by in conjunction with the built-in error handler, or with a user defined function that has been set as the new error handler (set_error_handler()). It only works with the E_USER family of constants, and will default to E_USER_NOTICE.

This function is useful when you need to generate a particular response to an exception at runtime. For example:

if (assert ($divisor == 0))
   trigger_error ("Cannot divide by zero", E_USER_ERROR);

Poznámka: See set_error_handler() for a more extensive example.

user_error

(PHP 4 )

user_error -- Generates a user-level error/warning/notice message

Description

void user_error ( string error_msg [, int error_type])

This is an alias for the function trigger_error().

XXVIII. FrontBase Functions

Úvod

These functions allow you to access FrontBase database servers. More information about FrontBase can be found at http://www.frontbase.com/.

Documentation for FrontBase can be found at http://www.frontbase.com/cgi-bin/WebObjects/FrontBase.woa/wa/productsPage?currentPage=Documentation.

Frontbase support has been added to PHP 4.0.6.

Požadavky

You must install the FrontBase database server or at least the fbsql client libraries to use this functions. You can get FrontBase from http://www.frontbase.com/.

Instalace

In order to have these functions available, you must compile PHP with fbsql support by using the --with-fbsql option. If you use this option without specifying the path to fbsql, PHP will search for the fbsql client libraries in the default installation location for the platform. Users who installed FrontBase in a non standard directory should always specify the path to fbsql: --with-fbsql=/path/to/fbsql. This will force PHP to use the client libraries installed by FrontBase, avoiding any conflicts.

Konfigurace běhu

Typy prostředků

Předdefinované konstanty

Tyto konstanty jsou definovány tímto rozšířením a budou k dispozici pouze tehdy, bylo-li rozšíření zkompilováno společně s PHP nebo dynamicky zavedeno za běhu.

FBSQL_ASSOC (integer)
FBSQL_NUM (integer)
FBSQL_BOTH (integer)
FBSQL_LOCK_DEFERRED (integer)
FBSQL_LOCK_OPTIMISTIC (integer)
FBSQL_LOCK_PESSIMISTIC (integer)
FBSQL_ISO_READ_UNCOMMITTED (integer)
FBSQL_ISO_READ_COMMITTED (integer)
FBSQL_ISO_REPEATABLE_READ (integer)
FBSQL_ISO_SERIALIZABLE (integer)
FBSQL_ISO_VERSIONED (integer)
FBSQL_UNKNOWN (integer)
FBSQL_STOPPED (integer)
FBSQL_STARTING (integer)
FBSQL_RUNNING (integer)
FBSQL_STOPPING (integer)
FBSQL_NOEXEC (integer)
FBSQL_LOB_DIRECT (integer)
FBSQL_LOB_HANDLE (integer)

Obsah
fbsql_affected_rows -- Get number of affected rows in previous FrontBase operation
fbsql_autocommit -- Enable or disable autocommit
fbsql_change_user -- Change logged in user of the active connection
fbsql_close -- Close FrontBase connection
fbsql_commit -- Commits a transaction to the database
fbsql_connect -- Open a connection to a FrontBase Server
fbsql_create_blob -- Create a BLOB
fbsql_create_clob -- Create a CLOB
fbsql_create_db -- Create a FrontBase database
fbsql_data_seek -- Move internal result pointer
fbsql_database_password -- Sets or retrieves the password for a FrontBase database
fbsql_database -- Get or set the database name used with a connection
fbsql_db_query -- Send a FrontBase query
fbsql_db_status -- Get the status for a given database
fbsql_drop_db -- Drop (delete) a FrontBase database
fbsql_errno -- Returns the numerical value of the error message from previous FrontBase operation
fbsql_error -- Returns the text of the error message from previous FrontBase operation
fbsql_fetch_array -- Fetch a result row as an associative array, a numeric array, or both
fbsql_fetch_assoc -- Fetch a result row as an associative array
fbsql_fetch_field -- Get column information from a result and return as an object
fbsql_fetch_lengths -- Get the length of each output in a result
fbsql_fetch_object -- Fetch a result row as an object
fbsql_fetch_row -- Get a result row as an enumerated array
fbsql_field_flags -- Get the flags associated with the specified field in a result
fbsql_field_len -- Returns the length of the specified field
fbsql_field_name -- Get the name of the specified field in a result
fbsql_field_seek -- Set result pointer to a specified field offset
fbsql_field_table -- Get name of the table the specified field is in
fbsql_field_type -- Get the type of the specified field in a result
fbsql_free_result -- Free result memory
fbsql_get_autostart_info -- No description given yet
fbsql_hostname -- Get or set the host name used with a connection
fbsql_insert_id -- Get the id generated from the previous INSERT operation
fbsql_list_dbs -- List databases available on a FrontBase server
fbsql_list_fields -- List FrontBase result fields
fbsql_list_tables -- List tables in a FrontBase database
fbsql_next_result -- Move the internal result pointer to the next result
fbsql_num_fields -- Get number of fields in result
fbsql_num_rows -- Get number of rows in result
fbsql_password -- Get or set the user password used with a connection
fbsql_pconnect -- Open a persistent connection to a FrontBase Server
fbsql_query -- Send a FrontBase query
fbsql_read_blob -- Read a BLOB from the database
fbsql_read_clob -- Read a CLOB from the database
fbsql_result -- Get result data
fbsql_rollback -- Rollback a transaction to the database
fbsql_select_db -- Select a FrontBase database
fbsql_set_lob_mode -- Set the LOB retrieve mode for a FrontBase result set
fbsql_set_transaction -- Set the transaction locking and isolation
fbsql_start_db -- Start a database on local or remote server
fbsql_stop_db -- Stop a database on local or remote server
fbsql_tablename -- Get table name of field
fbsql_username -- Get or set the host user used with a connection
fbsql_warnings -- Enable or disable FrontBase warnings

fbsql_affected_rows

(PHP 4 >= 4.0.6)

fbsql_affected_rows -- Get number of affected rows in previous FrontBase operation

Description

int fbsql_affected_rows ( [resource link_identifier])

fbsql_affected_rows() returns the number of rows affected by the last INSERT, UPDATE or DELETE query associated with link_identifier. If the link identifier isn't specified, the last link opened by fbsql_connect() is assumed.

Poznámka: If you are using transactions, you need to call fbsql_affected_rows() after your INSERT, UPDATE, or DELETE query, not after the commit.

If the last query was a DELETE query with no WHERE clause, all of the records will have been deleted from the table but this function will return zero.

Poznámka: When using UPDATE, FrontBase will not update columns where the new value is the same as the old value. This creates the possibility that fbsql_affected_rows() may not actually equal the number of rows matched, only the number of rows that were literally affected by the query.

Returns: TRUE on success, FALSE on error.

fbsql_close() closes the connection to the FrontBase server that's associated with the specified link identifier. If link_identifier isn't specified, the last opened link is used.

Using fbsql_close() isn't usually necessary, as non-persistent open links are automatically closed at the end of the script's execution.

Příklad 1. fbsql_close() example

<?php
    $link = fbsql_connect ("localhost", "_SYSTEM", "secret")
        or die ("Could not connect");
    print ("Connected successfully");
    fbsql_close ($link);
?>

fbsql_commit

(PHP 4 >= 4.0.6)

fbsql_commit -- Commits a transaction to the database

Description

bool fbsql_commit ( [resource link_identifier])

Vrací TRUE při úspěchu, FALSE při selhání.

fbsql_commit() ends the current transaction by writing all inserts, updates and deletes to the disk and unlocking all row and table locks held by the transaction. This command is only needed if autocommit is set to false.

fbsql_connect

(PHP 4 >= 4.0.6)

fbsql_connect -- Open a connection to a FrontBase Server

Description

resource fbsql_connect ( [string hostname [, string username [, string password]]])

Returns a positive FrontBase link identifier on success, or an error message on failure.

fbsql_connect() establishes a connection to a FrontBase server. The following defaults are assumed for missing optional parameters: hostname = 'NULL', username = '_SYSTEM' and password = empty password.

If a second call is made to fbsql_connect() with the same arguments, no new link will be established, but instead, the link identifier of the already opened link will be returned.

The link to the server will be closed as soon as the execution of the script ends, unless it's closed earlier by explicitly calling fbsql_close().

Příklad 1. fbsql_connect() example

<?php

    $link = fbsql_connect ("localhost", "_SYSTEM", "secret")
        or die ("Could not connect");
    print ("Connected successfully");
    fbsql_close ($link);

?>

fbsql_create_blob

(PHP 4 >= 4.2.0)

fbsql_create_blob -- Create a BLOB

Description

string fbsql_create_blob ( string blob_data [, resource link_identifier])

Returns: A resource handle to the newly created blob.

fbsql_create_blob() creates a blob from blob_data. The returned resource handle can be used with insert and update commands to store the blob in the database.

Příklad 1. fbsql_create_blob() example

<?php
    $link = fbsql_pconnect ("localhost", "_SYSTEM", "secret")
        or die ("Could not connect");
    $filename = "blobfile.bin";
    $fp = fopen($filename, "rb");
    $blobdata = fread($fp, filesize($filename));
    fclose($fp);
    
    $blobHandle = fbsql_create_blob($blobdata, $link);
    
    $sql = "INSERT INTO BLOB_TABLE (BLOB_COLUMN) VALUES ($blobHandle);";
    $rs = fbsql_query($sql, $link);
?>

fbsql_create_clob

(PHP 4 >= 4.2.0)

fbsql_create_clob -- Create a CLOB

Description

string fbsql_create_clob ( string clob_data [, resource link_identifier])

Returns: A resource handle to the newly created CLOB.

fbsql_create_clob() creates a clob from clob_data. The returned resource handle can be used with insert and update commands to store the clob in the database.

Příklad 1. fbsql_create_clob() example

<?php
    $link = fbsql_pconnect ("localhost", "_SYSTEM", "secret")
        or die ("Could not connect");
    $filename = "clob_file.txt";
    $fp = fopen($filename, "rb");
    $clobdata = fread($fp, filesize($filename));
    fclose($fp);
    
    $clobHandle = fbsql_create_clob($clobdata, $link);
    
    $sql = "INSERT INTO CLOB_TABLE (CLOB_COLUMN) VALUES ($clobHandle);";
    $rs = fbsql_query($sql, $link);
?>

fbsql_create_db

(PHP 4 >= 4.0.6)

fbsql_create_db -- Create a FrontBase database

Description

bool fbsql_create_db ( string database name [, resource link_identifier])

fbsql_create_db() attempts to create a new database on the server associated with the specified link identifier.

Příklad 1. fbsql_create_db() example

<?php
    $link = fbsql_pconnect ("localhost", "_SYSTEM", "secret")
        or die ("Could not connect");
    if (fbsql_create_db ("my_db")) {
        print("Database created successfully\n");
    } else {
        printf("Error creating database: %s\n", fbsql_error ());
    }
?>

fbsql_data_seek

(PHP 4 >= 4.0.6)

fbsql_data_seek -- Move internal result pointer

Description

bool fbsql_data_seek ( resource result_identifier, int row_number)

Vrací TRUE při úspěchu, FALSE při selhání.

fbsql_data_seek() moves the internal row pointer of the FrontBase result associated with the specified result identifier to point to the specified row number. The next call to fbsql_fetch_row() would return that row.

Row_number starts at 0.

Příklad 1. fbsql_data_seek() example

<?php
    $link = fbsql_pconnect ("localhost", "_SYSTEM", "secret")
        or die ("Could not connect");

    fbsql_select_db ("samp_db")
        or die ("Could not select database");

    $query = "SELECT last_name, first_name FROM friends;";
    $result = fbsql_query ($query)
        or die ("Query failed");

    # fetch rows in reverse order

    for ($i = fbsql_num_rows ($result) - 1; $i >=0; $i--) {
        if (!fbsql_data_seek ($result, $i)) {
            printf ("Cannot seek to row %d\n", $i);
            continue;
        }

        if(!($row = fbsql_fetch_object ($result)))
            continue;

        printf("%s %s<BR>\n", $row->last_name, $row->first_name);
    }

    fbsql_free_result ($result);
?>

fbsql_database_password

(PHP 4 >= 4.0.6)

fbsql_database_password -- Sets or retrieves the password for a FrontBase database

Description

string fbsql_database_password ( resource link_identifier [, string database_password])

Returns: The database password associated with the link identifier.

fbsql_database_password() sets and retrieves the database password used by the connection. if a database is protected by a database password, the user must call this function before calling fbsql_select_db(). if the second optional parameter is given the function sets the database password for the specified link identifier. If no link identifier is specified, the last opened link is assumed. If no link is open, the function will try to establish a link as if fbsql_connect() was called, and use it.

This function does not change the database password in the database nor can it be used to retrive the database password for a database.

Příklad 1. fbsql_create_clob() example

<?php
    $link = fbsql_pconnect ("localhost", "_SYSTEM", "secret")
        or die ("Could not connect");
    fbsql_database_password($link, "secret db password");
    fbsql_select_db($database, $link);
?>

The return value can be one of the following constants:

FALSE - The exec handler for the host was invalid. This error will occur when the link_identifier connects directly to a database by using a port number. FBExec can be available on the server but no connection has been made for it.
FBSQL_UNKNOWN - The Status is unknown.
FBSQL_STOPPED - The database is not running. Use fbsql_start_db() to start the database.
FBSQL_STARTING - The database is starting.
FBSQL_RUNNING - The database is running and can be used to perform SQL operations.
FBSQL_STOPPING - The database is stopping.
FBSQL_NOEXEC - FBExec is not running on the server and it is not possible to get the status of the database.

fbsql_drop_db

(PHP 4 >= 4.0.6)

fbsql_drop_db -- Drop (delete) a FrontBase database

Description

fbsql_fetch_array() is an extended version of fbsql_fetch_row(). In addition to storing the data in the numeric indices of the result array, it also stores the data in associative indices, using the field names as keys.

If two or more columns of the result have the same field names, the last column will take precedence. To access the other column(s) of the same name, you must the numeric index of the column or make an alias for the column.

select t1.f1 as foo t2.f1 as bar from t1, t2

An important thing to note is that using fbsql_fetch_array() is NOT significantly slower than using fbsql_fetch_row(), while it provides a significant added value.

The optional second argument result_type in fbsql_fetch_array() is a constant and can take the following values: FBSQL_ASSOC, FBSQL_NUM, and FBSQL_BOTH.

For further details, see also fbsql_fetch_row() and fbsql_fetch_assoc().

Příklad 1. fbsql_fetch_array() example

<?php 
fbsql_connect ($host, $user, $password);
$result = fbsql_db_query ("database","select user_id, fullname from table");
while ($row = fbsql_fetch_array ($result)) {
    echo "user_id: ".$row["user_id"]."<br>\n";
    echo "user_id: ".$row[0]."<br>\n";
    echo "fullname: ".$row["fullname"]."<br>\n";
    echo "fullname: ".$row[1]."<br>\n";
}
fbsql_free_result ($result);
?>

fbsql_fetch_assoc

(PHP 4 >= 4.0.6)

fbsql_fetch_assoc -- Fetch a result row as an associative array

Description

array fbsql_fetch_assoc ( resource result)

Returns an associative array that corresponds to the fetched row, or FALSE if there are no more rows.

fbsql_fetch_assoc() is equivalent to calling fbsql_fetch_array() with FBSQL_ASSOC for the optional second parameter. It only returns an associative array. This is the way fbsql_fetch_array() originally worked. If you need the numeric indices as well as the associative, use fbsql_fetch_array().

If two or more columns of the result have the same field names, the last column will take precedence. To access the other column(s) of the same name, you must use fbsql_fetch_array() and have it return the numeric indices as well.

An important thing to note is that using fbsql_fetch_assoc() is NOT significantly slower than using fbsql_fetch_row(), while it provides a significant added value.

For further details, see also fbsql_fetch_row() and fbsql_fetch_array().

Příklad 1. fbsql_fetch_assoc() example

<?php 
fbsql_connect ($host, $user, $password);
$result = fbsql_db_query ("database","select * from table");
while ($row = fbsql_fetch_assoc ($result)) {
    echo $row["user_id"];
    echo $row["fullname"];
}
fbsql_free_result ($result);
?>

fbsql_fetch_field

(PHP 4 >= 4.0.6)

fbsql_fetch_field -- Get column information from a result and return as an object

Description

object fbsql_fetch_field ( resource result [, int field_offset])

Returns an object containing field information.

fbsql_fetch_field() can be used in order to obtain information about fields in a certain query result. If the field offset isn't specified, the next field that wasn't yet retrieved by fbsql_fetch_field() is retrieved.

The properties of the object are:

name - column name
table - name of the table the column belongs to
max_length - maximum length of the column
not_null - 1 if the column cannot be NULL
type - the type of the column

Příklad 1. fbsql_fetch_field() example

<?php 
fbsql_connect ($host, $user, $password)
    or die ("Could not connect");
$result = fbsql_db_query ("database", "select * from table")
    or die ("Query failed");
# get column metadata
$i = 0;
while ($i < fbsql_num_fields ($result)) {
    echo "Information for column $i:<BR>\n";
    $meta = fbsql_fetch_field ($result);
    if (!$meta) {
        echo "No information available<BR>\n";
    }
    echo "<PRE>
max_length:   $meta->max_length
name:         $meta->name
not_null:     $meta->not_null
table:        $meta->table
type:         $meta->type
</PRE>";
    $i++;
}
fbsql_free_result ($result);
?>

fbsql_fetch_lengths

(PHP 4 >= 4.0.6)

fbsql_fetch_lengths -- Get the length of each output in a result

Description

array fbsql_fetch_lengths ( [resource result])

Returns: An array that corresponds to the lengths of each field in the last row fetched by fbsql_fetch_row(), or FALSE on error.

fbsql_fetch_lengths() stores the lengths of each result column in the last row returned by fbsql_fetch_row(), fbsql_fetch_array() and fbsql_fetch_object() in an array, starting at offset 0.

fbsql_fetch_object

(PHP 4 >= 4.0.6)

fbsql_fetch_object -- Fetch a result row as an object

Description

object fbsql_fetch_object ( resource result [, int result_type])

Returns an object with properties that correspond to the fetched row, or FALSE if there are no more rows.

fbsql_fetch_object() is similar to fbsql_fetch_array(), with one difference - an object is returned, instead of an array. Indirectly, that means that you can only access the data by the field names, and not by their offsets (numbers are illegal property names).

The optional argument result_type is a constant and can take the following values: FBSQL_ASSOC, FBSQL_NUM, and FBSQL_BOTH.

Speed-wise, the function is identical to fbsql_fetch_array(), and almost as quick as fbsql_fetch_row() (the difference is insignificant).

Příklad 1. fbsql_fetch_object() example

<?php fbsql_connect ($host, $user, $password); $result = fbsql_db_query ("database", "select * from table"); while ($row = fbsql_fetch_object ($result)) { echo $row->user_id; echo $row->fullname; } fbsql_free_result ($result); ?>

fbsql_fetch_row

(PHP 4 >= 4.0.6)

fbsql_fetch_row -- Get a result row as an enumerated array

Description

array fbsql_fetch_row ( resource result)

Returns: An array that corresponds to the fetched row, or FALSE if there are no more rows.

fbsql_fetch_row() fetches one row of data from the result associated with the specified result identifier. The row is returned as an array. Each result column is stored in an array offset, starting at offset 0.

fbsql_field_name() returns the name of the specified field index. result must be a valid result identifier and field_index is the numerical offset of the field.

Poznámka: field_index starts at 0.

e.g. The index of the third field would actually be 2, the index of the fourth field would be 3 and so on.

Příklad 1. fbsql_field_name() example

// The users table consists of three fields: // user_id // username // password. $res = fbsql_db_query("users", "select * from users", $link); echo fbsql_field_name($res, 0) . "\n"; echo fbsql_field_name($res, 2);

The above example would produce the following output:

user_id
password

fbsql_insert_id() returns 0 if the previous query does not generate an DEFAULT UNIQUE value. If you need to save the value for later, be sure to call fbsql_insert_id() immediately after the query that generates the value.

Poznámka: The value of the FrontBase SQL function LAST_INSERT_ID() always contains the most recently generated DEFAULT UNIQUE value, and is not reset between queries.

fbsql_list_dbs

(PHP 4 >= 4.0.6)

fbsql_list_dbs -- List databases available on a FrontBase server

Description

resource fbsql_list_dbs ( [resource link_identifier])

fbsql_list_dbs() will return a result pointer containing the databases available from the current fbsql daemon. Use the fbsql_tablename() function to traverse this result pointer.

Příklad 1. fbsql_list_dbs() example

$link = fbsql_connect('localhost', 'myname', 'secret'); $db_list = fbsql_list_dbs($link); while ($row = fbsql_fetch_object($db_list)) { echo $row->Database . "\n"; }

The above example would produce the following output:

database1
database2
database3
...

Poznámka: The above code would just as easily work with fbsql_fetch_row() or other similar functions.

fbsql_list_fields

(PHP 4 >= 4.0.6)

fbsql_list_fields -- List FrontBase result fields

Description

resource fbsql_list_fields ( string database_name, string table_name [, resource link_identifier])

fbsql_list_fields() retrieves information about the given tablename. Arguments are the database name and the table name. A result pointer is returned which can be used with fbsql_field_flags(), fbsql_field_len(), fbsql_field_name(), and fbsql_field_type().

A result identifier is a positive integer. The function returns -1 if a error occurs. A string describing the error will be placed in $phperrmsg, and unless the function was called as @fbsql() then this error string will also be printed out.

Příklad 1. fbsql_list_fields() example

$link = fbsql_connect('localhost', 'myname', 'secret'); $fields = fbsql_list_fields("database1", "table1", $link); $columns = fbsql_num_fields($fields); for ($i = 0; $i < $columns; $i++) { echo fbsql_field_name($fields, $i) . "\n";; }

The above example would produce the following output:

field1
field2
field3
...

fbsql_list_tables

(PHP 4 >= 4.0.6)

fbsql_list_tables -- List tables in a FrontBase database

Description

resource fbsql_list_tables ( string database [, resource link_identifier])

fbsql_list_tables() takes a database name and returns a result pointer much like the fbsql_db_query() function. The fbsql_tablename() function should be used to extract the actual table names from the result pointer.

fbsql_next_result

(PHP 4 >= 4.0.6)

fbsql_next_result -- Move the internal result pointer to the next result

Description

bool fbsql_next_result ( resource result_id)

When sending more than one SQL statement to the server or executing a stored procedure with multiple results will cause the server to return multiple result sets. This function will test for additional results available form the server. If an additional result set exists it will free the existing result set and prepare to fetch the words from the new result set. The function will return TRUE if an additional result set was available or FALSE otherwise.

Příklad 1. fbsql_next_result() example

<?php
    $link = fbsql_connect ("localhost", "_SYSTEM", "secret");
    fbsql_select_db("MyDB", $link);
    $SQL = "Select * from table1; select * from table2;";
    $rs = fbsql_query($SQL, $link);
    do {
        while ($row = fbsql_fetch_row($rs)) {
        }
    } while (fbsql_next_result($rs));
    fbsql_free_result($rs);
    fbsql_close ($link);
?>

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

fbsql_pconnect

(PHP 4 >= 4.0.6)

fbsql_pconnect -- Open a persistent connection to a FrontBase Server

Description

resource fbsql_pconnect ( [string hostname [, string username [, string password]]])

Returns: A positive FrontBase persistent link identifier on success, or FALSE on error.

fbsql_pconnect() establishes a connection to a FrontBase server. The following defaults are assumed for missing optional parameters: host = 'localhost', username = "_SYSTEM" and password = empty password.

fbsql_pconnect() acts very much like fbsql_connect() with two major differences.

To set Frontbase server port number, use fbsql_select_db().

First, when connecting, the function would first try to find a (persistent) link that's already open with the same host, username and password. If one is found, an identifier for it will be returned instead of opening a new connection.

Second, the connection to the SQL server will not be closed when the execution of the script ends. Instead, the link will remain open for future use.

This type of links is therefore called 'persistent'.

fbsql_query

(PHP 4 >= 4.0.6)

fbsql_query -- Send a FrontBase query

Description

resource fbsql_query ( string query [, resource link_identifier])

fbsql_query() sends a query to the currently active database on the server that's associated with the specified link identifier. If link_identifier isn't specified, the last opened link is assumed. If no link is open, the function tries to establish a link as if fbsql_connect() was called with no arguments, and use it.

Poznámka: The query string shall always end with a semicolon.

mixed fbsql_result ( resource result, int row [, mixed field])

fbsql_result() returns the contents of one cell from a FrontBase result set. The field argument can be the field's offset, or the field's name, or the field's table dot field's name (tabledname.fieldname). If the column name has been aliased ('select foo as bar from...'), use the alias instead of the column name.

When working on large result sets, you should consider using one of the functions that fetch an entire row (specified below). As these functions return the contents of multiple cells in one function call, they're MUCH quicker than fbsql_result(). Also, note that specifying a numeric offset for the field argument is much quicker than specifying a fieldname or tablename.fieldname argument.

Calls to fbsql_result() should not be mixed with calls to other functions that deal with the result set.

Recommended high-performance alternatives: fbsql_fetch_row(), fbsql_fetch_array(), and fbsql_fetch_object().

fbsql_rollback

(PHP 4 >= 4.0.6)

fbsql_rollback -- Rollback a transaction to the database

Description

bool fbsql_rollback ( [resource link_identifier])

Vrací TRUE při úspěchu, FALSE při selhání.

fbsql_rollback() ends the current transaction by rolling back all statements issued since last commit. This command is only needed if autocommit is set to false.

fbsql_select_db

(PHP 4 >= 4.0.6)

fbsql_select_db -- Select a FrontBase database

Description

bool fbsql_select_db ( string database_name [, resource link_identifier])

Returns: TRUE on success, FALSE on error.

fbsql_select_db() sets the current active database on the server that's associated with the specified link identifier. If no link identifier is specified, the last opened link is assumed. If no link is open, the function will try to establish a link as if fbsql_connect() was called, and use it.

The client contacts FBExec to obtain the port number to use for the connection to the database. If the database name is a number the system will use that as a port number and it will not ask FBExec for the port number. The FrontBase server can be stared as FRontBase -FBExec=No -port=<port number> <database name>.

Every subsequent call to fbsql_query() will be made on the active database.

if the database is protected with a database password, the user must call fbsql_database_password() before selecting the database.

fbsql_set_lob_mode

(PHP 4 >= 4.2.0)

fbsql_set_lob_mode -- Set the LOB retrieve mode for a FrontBase result set

Description

bool fbsql_set_lob_mode ( resource result, string database_name)

Returns: TRUE on success, FALSE on error.

fbsql_set_lob_mode() sets the mode for retrieving LOB data from the database. When BLOB and CLOB data is stored in FrontBase it can be stored direct or indirect. Direct stored LOB data will always be fetched no matter the setting of the lob mode. If the LOB data is less than 512 bytes it will always be stored directly.

FBSQL_LOB_DIRECT - LOB data is retrieved directly. When data is fetched from the database with fbsql_fetch_row(), and other fetch functions, all CLOB and BLOB columns will be returned as ordinary columns. This is the default value on a new FrontBase result.
FBSQL_LOB_HANDLE - LOB data is retrieved as handles to the data. When data is fetched from the database with fbsql_fetch_row (), and other fetch functions, LOB data will be returned as a handle to the data if the data is stored indirect or the data if it is stored direct. If a handle is returned it will be a 27 byte string formatted as "@'000000000000000000000000'".

(PHP 4 >= 4.0.6)

fbsql_username -- Get or set the host user used with a connection

Description

string fbsql_username ( resource link_identifier [, string username])

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

fbsql_warnings

(PHP 4 >= 4.0.6)

fbsql_warnings -- Enable or disable FrontBase warnings

Description

bool fbsql_warnings ( [bool OnOff])

Returns TRUE if warnings is turned on otherwise FALSE.

fbsql_warnings() enables or disables FrontBase warnings.

XXIX. filePro funkce

Tyto funkce umožňují read-only (pouze pro čtení) přístup k datům uloženým ve filePro databázích.

filePro je registrovaná obchodní značka fP Technologies, Inc. Více informací o filePro najdete na http://www.fptech.com/.

Obsah
filepro_fieldcount -- Zjistit, kolik sloupců je ve filePro databázi
filepro_fieldname -- Zjistit název sloupce
filepro_fieldtype -- Zjistit typ sloupce
filepro_fieldwidth -- Zjistit šířku sloupce
filepro_retrieve -- Získat data z filePro databáze
filepro_rowcount -- Zjistit, kolik řádků je ve filePro databázi
filepro -- Přečíst a ověřit mapový soubor

filepro_fieldcount

(PHP 3, PHP 4 )

filepro_fieldcount -- Zjistit, kolik sloupců je ve filePro databázi

Popis

int filepro_fieldcount ( void)

int filepro_rowcount ( void)

Vrátí počet řádků v otevřené filePro databázi.

Viz také filepro().

filepro

(PHP 3, PHP 4 )

filepro -- Přečíst a ověřit mapový soubor

Popis

bool filepro ( string directory)

Přečte a ověří mapový soubor a uloží počet sloupců a info.

Nedochází k zamykání, takže byste se měli vyhnout úpravám vaší filePro databáze, pokud může být otevřena v PHP.

XXX. Filesystémové funkce

Obsah
basename -- Vrátí část cesty obsahující název souboru
chgrp -- Změnit skupinu souboru
chmod -- Změnit mód souboru
chown -- Změní vlastníka souboru
clearstatcache -- Vymaže cache stavu souborů
copy -- Zkopíruje soubor
delete -- Falešná položka manuálu
dirname -- Vrací část cesty obsahující název adresáře
disk_free_space -- Returns available space in directory
disk_total_space -- Returns the total size of a directory
diskfreespace -- Vrátí diskový prostor dostupný v adresáři
fclose -- Zavře otevřený deskriptor souboru
feof -- Test na konec souboru
fflush -- Zapíše obsah výstupního bufferu
fgetc -- Načte 1 znak ze souboru
fgetcsv -- Načte řádek ze souboru a parsuje ho na CSV hodnoty
fgets -- Přečte řádek ze souboru
fgetss -- Přečte řádek ze souboru a odstraní HTML značky
file_exists -- Zjistí, zda soubor existuje
file_get_contents -- Reads entire file into a string
file_get_wrapper_data -- Retrieves header/meta data from "wrapped" file pointers
file_register_wrapper -- Register a URL wrapper implemented as a PHP class
file -- Načte celý soubor do pole
fileatime -- Vrací čas posledního přístupu k souboru
filectime -- Vrací čas změny inodu souboru
filegroup -- Vrací skupinu pro soubor
fileinode -- Vrací inode souboru
filemtime -- Vrací čas změny souboru
fileowner -- Vrací vlastníka souboru
fileperms -- Vrací přístupová práva k souboru
filesize -- Vrací velikost souboru
filetype -- Vrací typ souboru
flock -- Jednotné "portable advisory" zamykání souboru
fopen -- Otevře soubor nebo URL
fpassthru -- Vypíše všechna zbývající data v souboru
fputs -- Zapíše do souboru
fread -- Binárně bezpečné čtení ze souboru
fscanf -- Parsuje vstup ze souboru podle formátu
fseek -- Posouvá ukazatel v souboru
fstat -- Vrací informace o otevřeném souboru
ftell -- Vrací pozici v souboru
ftruncate -- Zkrátí soubor na danou délku
fwrite -- Binárně bezpečný zápis do souboru
glob -- Find pathnames matching a pattern
is_dir -- Zjistí, zda je daný soubor adresářem
is_executable -- Zjistí, zda je soubor spustitelný
is_file -- Zjistí, zda se jedná o obyčejný (regular) soubor
is_link -- Zjistí, zda se jedná o symbolický odkaz (link)
is_readable -- Zjistí, zda lze ze souboru číst
is_uploaded_file -- Zjistí, zda byl soubor uploadován pomocí HTTP POST
is_writable -- Zjistí, zda lze do souboru zapisovat
is_writeable -- Tells whether the filename is writable
link -- Vytvoří hard link
linkinfo -- Vrací informaci o odkazu (linku)
lstat -- Zjišťuje informace o souboru nebo symbolickém odkazu
mkdir -- Vytvoří adresář
move_uploaded_file -- Přesune uploadovaný soubor na nové místo
parse_ini_file -- Parse a configuration file
pathinfo -- Returns information about a file path
pclose -- Zavře procesový soubor (rouru)
popen -- Otevře procesový soubor (rouru)
readfile -- Vypíše soubor
readlink -- Vrací cíl symbolického odkazu
realpath -- Vrátí absolutní cestu v kanonickém tvaru
rename -- Přejmenuje soubor
rewind -- Vrátí ukazatel v souboru na začátek
rmdir -- Odstraní adresář
set_file_buffer -- Nastaví buffer pro soubor
stat -- Zjišťuje informace o souboru
symlink -- Vytvoří symbolický odkaz
tempnam -- Vytvoří soubor s unikátním názvem
tmpfile -- Vytvoří dočasný soubor
touch -- Nastavit čas změny souboru
umask -- Změní současné nastavení umask
unlink -- Smazat soubor

Viz také chown() a chgrp().

Poznámka: Tato funkce nefunguje na Windows systémech

chown

(PHP 3, PHP 4 )

chown -- Změní vlastníka souboru

Popis

int chown ( string filename, mixed user)

Pokusí se změnit vlastníka souboru na user. Pouze superuživatel může změnit majitele souboru.

Při úspěchu vrací TRUE, jinak FALSE.

Viz také chown() a chmod().

Poznámka: Tato funkce nefunguje na Windows systémech

clearstatcache

(PHP 3, PHP 4 )

clearstatcache -- Vymaže cache stavu souborů

Popis

void clearstatcache ( void)

string dirname ( string path)

Přijímá řetězec obsahující cestu na soubor a vrací název adresáře.

Na Windows se jako oddělovač sesty dají používat jak lomítko (/), tak zpětné lomítko (\). Na ostatních systémech je to lomítko (/).

Příklad 1. Ukázka dirname()

$path = "/etc/passwd"; $file = dirname ($path); // $file obsahuje "/etc"

Viz také basename()

disk_free_space

(PHP 4 >= 4.1.0)

disk_free_space -- Returns available space in directory

Description

float disk_free_space ( string directory)

Given a string containing a directory, this function will return the number of bytes available on the corresponding filesystem or disk partition.

Příklad 1. disk_free_space() example

$df = disk_free_space("/"); // $df contains the number of bytes // available on "/"

disk_total_space

(PHP 4 >= 4.1.0)

disk_total_space -- Returns the total size of a directory

Description

float disk_total_space ( string directory)

Given a string containing a directory, this function will return the total number of bytes on the corresponding filesystem or disk partition.

Příklad 1. disk_total_space() example

$df = disk_total_space("/"); // $df contains the total number of // bytes available on "/"

diskfreespace

(PHP 3>= 3.0.7, PHP 4 )

diskfreespace -- Vrátí diskový prostor dostupný v adresáři

Popis

float diskfreespace ( string directory)

Přijímá řetězec obsahující cestu na adresář, vrací počet bytů dostupných na odpovídajícím filesystému nebo oddílu.

Příklad 1. Ukázka diskfreespace()

$df = diskfreespace("/"); // $df obsahuje pocet bytu // dostupnych na "/"

fclose

(PHP 3, PHP 4 )

fclose -- Zavře otevřený deskriptor souboru

Popis

int fclose ( int fp)

Viz také fgets(), fopen(), fsockopen(), popen(), a strip_tags().

file_exists

(PHP 3, PHP 4 )

file_exists -- Zjistí, zda soubor existuje

Popis

bool file_exists ( string filename)

Vrací TRUE, pokud soubor specifikovaný pomocí filename existuje, jinak FALSE.

file_exists() nefunguje na vzdálených souborech; soubor k ověření musí být přístupný prostřednictvím filesystému serveru.

Výsledek této funkce je cachován. Více informací - viz clearstatcache().

file_get_contents

(PHP 4 CVS only)

file_get_contents -- Reads entire file into a string

Description

string file_get_contents ( string filename [, int use_include_path])

Identical to readfile(), except that file_get_contents() returns the file in a string.

Poznámka: Tato funkce je binárně bezpečná.

Tip: S touto funkcí můžete používat URL jako název souboru, pokud je zapnuta volba "fopen wrappers". Více detailů - viz funkce fopen().

file_get_wrapper_data

(PHP 4 CVS only)

file_get_wrapper_data -- Retrieves header/meta data from "wrapped" file pointers

Description

mixed file_get_wrapper_data ( int fp)

This function returns header or meta data from files opened with fopen(). This is useful to return the response headers for HTTP connections, or some other statistics for other resources.

The format of the returned data is deliberately undocumented at this time, and depends on which wrapper(s) were used to open the file.

Poznámka: This function was introduced in PHP 4.3.0.

file_register_wrapper

(PHP 4 CVS only)

file_register_wrapper -- Register a URL wrapper implemented as a PHP class

Description

boolean file_register_wrapper ( string protocol, string classname)

This function is currently only documented by the example below:

Příklad 1. Implementing a base64 encoding protocol

class Base64EncodingStream { var $fp = null; function stream_open($path, $mode, $options, &$opened_path) { $this->fp = fopen($path, $mode); return is_resource($this->fp); } function stream_close() { fclose($this->fp); } function stream_read($count) { return false; // We only allow writing } function stream_write($data) { return fwrite($this->fp, base64_encode($data)); } function stream_flush() { fflush($this->fp); return true; } function stream_seek($offset, $whence) { return false; } function stream_gets() { return false; } function stream_tell() { return false; } function stream_eof() { return false; } } file_register_wrapper("base64", "Base64EncodingStream") or die("Failed to register protocol"); copy("/tmp/inputfile.txt", "base64:///tmp/outputfile.txt"); readfile("/tmp/outputfile");

file_register_wrapper() will return false if the protocol already has a handler, or if "fopen wrappers" are disabled.

Poznámka: This function was introduced in PHP 4.3.0.

file

(PHP 3, PHP 4 )

file -- Načte celý soubor do pole

Popis

array file ( string filename [, int use_include_path])

Identické s readfile(), soubor je však vrácen v podobě pole. Každý element pole odpovídá jednomu řádku v souboru včetně znaku konce řádku.

Můžete použít nepovinný druhý parametr a nastavit ho na "1", pokud chcete hledat soubor také v include_path.

<?php
// načti WWW stránku do pole a vytiskni ji
$fcontents = file ('http://www.php.net');
while (list ($line_num, $line) = each ($fcontents)) {
    echo "<b>Line $line_num:</b> " . htmlspecialchars ($line) . "<br>\n";
}

// načti WWW stránku do řetězce
$fcontents = join ('', file ('http://www.php.net'));
?>

Viz také readfile(), fopen(), fsockopen(), a popen().

fileatime

(PHP 3, PHP 4 )

fileatime -- Vrací čas posledního přístupu k souboru

Popis

int fileatime ( string filename)

Vrací čas posledního přístupu k souboru, při chybě FALSE. Čas je vrácen jako Unix timestamp.

Výsledek této funkce je cachován. Více informací - viz clearstatcache().

Pozn.: Atime (čas posl. přístupu) souboru se obvykle mění při čtení datových bloků ze souboru. To se může značně negativně projevit na výkonu systému, pokud aplikace přistupuje k velkému počtu souborů nebo adresářů. Některé Unixové filesystémy mohou mít atime deaktivován za účelem zvýšení výkonu pro takové aplikace; takovým případem jsou USENET news spools. Tehdy je tato funkce bezpředmětná.

filectime

(PHP 3, PHP 4 )

filectime -- Vrací čas změny inodu souboru

Popis

int filectime ( string filename)

int fileperms ( string filename)

Vrací přístupová práva (permissions) k souboru, při chybě FALSE.

Výsledek této funkce je cachován. Více informací - viz clearstatcache().

filesize

(PHP 3, PHP 4 )

filesize -- Vrací velikost souboru

Popis

int filesize ( string filename)

Vrací velikost souboru, při chybě FALSE.

Výsledek této funkce je cachován. Více informací - viz clearstatcache().

filetype

(PHP 3, PHP 4 )

filetype -- Vrací typ souboru

Popis

string filetype ( string filename)

Vrací typ souboru. Možné hodnoty jsou fifo, char, dir, block, link, file a unknown.

Při chybě vrací FALSE.

Výsledek této funkce je cachován. Více informací - viz clearstatcache().

flock

(PHP 3>= 3.0.7, PHP 4 )

flock -- Jednotné "portable advisory" zamykání souboru

Popis

bool flock ( int fp, int operation [, int wouldblock])

PHP podporuje "portable" způsob zamykání celých souborů na základě jednotného "advisory" principu (tzn. všechny přistupující programy musí používat tentýž systém zamykání, jinak to nebude fungovat).

flock() funguje na deskriptoru fp, který musí patřit otevřenému souboru. operation je jedna z následujících hodnot:

K získání sdíleného (shared) zámku (čtení) nastavte operation na LOCK_SH (resp. 1 u verzí do PHP 4.0.1).
K získání výhradního zámku (zápis) nastavte operation na LOCK_EX (resp. 2 u verzí do PHP 4.0.1).
K uvolnění zámku (sdíleného nebo výhradního) nastavte operation na LOCK_UN (resp. 3 u verzí do PHP 4.0.1).
Pokud nechcete, aby funkce flock() blokovala během zamykání, přidejte k operation hodnotu LOCK_NB (4 pro verze do PHP 4.0.1).

flock() umožnuje jednoduchý model čtení/zápis použitelný teoreticky na všech platformách (včetně většiny Unixů a nejspíš i Windows). Nepovinný třetí argument se nastaví na TRUE, pokud by zámek měl blokovat (EWOULDBLOCK errno podmínka).

flock() vrací TRUE při úspěchu, FALSE při chybě (např. když nelze vytvořit zámek).

Varování

Na většině operačních systémů je funkce flock() implementována na úrovni procesů. Při použití multithreadového serverového API (jako je ISAPI) nemůžete spoléhat na ochranu souborů proti jiným PHP skriptům běžícím v paralelních vláknech stejné instance serveru!

fopen

(PHP 3, PHP 4 )

fopen -- Otevře soubor nebo URL

Popis

int fopen ( string filename, string mode [, int use_include_path])

Jestliže filename začíná "http://" (velkými nebo malými písmeny), je otevřeno spojení na příslušný server protokolem HTTP 1.0 a je vrácen deskriptor ukazující na začátek těla dokumentu. Posílá se hlavička 'Host:' pro přístup k virtuálním serverům založeným na jméně.

Nezpracovává HTTP přesměrování, je třeba vložit koncové lomítko za název adresáře.

Když filename začíná "ftp://" (velká či malá písmena), je otevřena FTP relace na příslušný server a vrácen deskriptor na požadovaný soubor. Pokud server nepodporuje pasivní režim FTP komunikace, selže to. Můžete přes FTP otvírat soubory pro čtení i zápis, ale ne pro obojí najednou.

Když filename je buď "php://stdin", "php://stdout", nebo "php://stderr", bude otevřen standardní vstup/výstup (stdio). (To platí od verze PHP 3.0.13; v dřívějších verzích se musí použít názvy jako "/dev/stdin" nebo "/dev/fd/0".)

Když filename začíná čímkoli jiným, bude otevřen obyčejný soubor (z filesystému) a vrácen jeho deskriptor.

Pokud otvírání selže, funkce vrátí FALSE.

mode může být kterýkoli z těchto:

'r' - Otevřít pouze pro čtení; nastaví ukazatel na začátek souboru.
'r+' - Otevřít pro čtení a zápis; nastaví ukazatel na začátek souboru.
'w' - Otevřít pouze pro zápis; nastaví ukazatel na začátek souboru a zkrátí soubor na nulovou délku. Pokud soubor neexistuje, pokusí se ho vytvořit.
'w+' - Otevřít pro čtení a zápis; nastaví ukazatel na začátek souboru a zkrátí soubor na nulovou délku. Pokud soubor neexistuje, pokusí se ho vytvořit.
'a' - Otevřít pouze pro zápis; nastaví ukazatel na konec souboru, Pokud soubor neexistuje, pokusí se ho vytvořit.
'a+' -Otevřít pro čtení a zápis; nastaví ukazatel na konec souboru. Pokud soubor neexistuje, pokusí se ho vytvořit.

mode může obsahovat písmeno 'b'. To je užitečné pouze na systémech které rozlišují mezi binárními a textovými soubory (nikoli např. na Unixu). Pokud není zapotřebí, je ignorován.

Můžete použít nepovinný třetí parametr a nastavit ho na "1", pokud chcete hledat soubor také v include_path.

Příklad 1. fopen() příklad

$fp = fopen ("/home/rasmus/file.txt", "r"); $fp = fopen ("/home/rasmus/file.gif", "wb"); $fp = fopen ("http://www.php.net/", "r"); $fp = fopen ("ftp://user:password@example.com/", "w");

Pokud jste zaznamenali problémy se čtením a zápisem do souborů a používáte PHP jako modul do serveru, nezapomeňte zajistit, aby soubory a adresáře, které používáte, byly přístupné pro serverový proces.

Na Windows je třeba oescapovat všechna zpětná lomítka ve specifikaci cesty k souboru nebo používat obyčejná (dopředná) lomítka.

$fp = fopen ("c:\\data\\info.txt", "r");

Viz také fclose(), fsockopen(), socket_set_timeout(), a popen().

fpassthru

(PHP 3, PHP 4 )

fpassthru -- Vypíše všechna zbývající data v souboru

Popis

int fpassthru ( int fp)

Čte až do dosažení konce souboru specifikovaného deskriptorem a načtené přepisuje na standardní výstup.

Pokud nastane chyba, funkce fpassthru() vrací FALSE.

Deskriptor souboru musí být platný a musí ukazovat na soubor úspěšně otevřený pomocí fopen(), popen(), nebo fsockopen(). Až funkce fpassthru() ukončí čtení, zavře soubor (deskriptor fp tím ztrácí smysl).

Když chcete vypsat obsah souboru na standardní výstup (stdout), můžete použí funkci readfile(), která vás ušetří volání funkce fopen().

Viz také readfile(), fopen(), popen(), a fsockopen()

fputs

(PHP 3, PHP 4 )

fputs -- Zapíše do souboru

Popis

int fputs ( int fp, string str [, int length])

Funkce fputs() je alias k fwrite() a je s ní tedy naprosto identická. Uvědomte si, že parametr length je nepovinný a pokud není specifikován, zapíše se celý řetezec.

fread

(PHP 3, PHP 4 )

fread -- Binárně bezpečné čtení ze souboru

Popis

string fread ( int fp, int length)

fread() přečte nejvýše length bytů ze souboru specifikovaného deskriptorem fp. Čtení končí, pokud je přečteno length bytů nebo je dosažen konec souboru (podle toho, co přijde dřív).

// nacte obsah souboru do retezce
$filename = "/usr/local/something.txt";
$fd = fopen ($filename, "r");
$contents = fread ($fd, filesize ($filename));
fclose ($fd);

Viz také fwrite(), fopen(), fsockopen(), popen(), fgets(), fgetss(), fscanf(), file(), a fpassthru().

fscanf

(PHP 4 >= 4.0.1)

fscanf -- Parsuje vstup ze souboru podle formátu

Popis

mixed fscanf ( int handle, string format [, string var1])

Funkce fscanf() je podobná sscanf(), ale načítá ze souboru specifikovaného handle a interpretuje vstupní data podle specifikovaného formátu format. Pokud má funkce pouze dva parametry, parsované hodnoty bude vráceny jako pole. Jinak, když jsou použity nepovinné parametry, funkce vrací určitý počet asignovaných hodnot. Nepovinné parametry musí být vloženy odkazem.

Příklad 1. fscanf() Příklad

$fp = fopen ("users.txt","r"); while ($userinfo = fscanf ($fp, "%s\t%s\t%s\n")) { list ($name, $profession, $countrycode) = $userinfo; //... udelej neco s hodnotami } fclose($fp);

Příklad 2. users.txt

javier argonaut pe hiroshi sculptor jp robert slacker us luigi florist it

Viz také fread(), fgets(), fgetss(), sscanf(), printf(), a sprintf().

fseek

(PHP 3, PHP 4 )

fseek -- Posouvá ukazatel v souboru

Popis

int fseek ( int fp, int offset [, int whence])

Nastaví ukazatel pozice v souboru specifikované pomocí deskriptoru fp. Nová pozice, měřená počtem bytů od začátku souboru, je získána přičtením hodnoty offset k pozici specifikované pomocí whence, jehož hodnota je definovanána:

SEEK_SET - Nastav na pozici rovnu offset bytů.

SEEK_CUR - Nastav pozici na současnou plus počet bytů v offset.

SEEK_END - Nastav na konec souboru plus offset bytů.

Pokud není parametr whence specifikován, použije se SEEK_SET.

Při úspěchu vrací 0, jinak -1. Pozn.: přesun za konec souboru není považován za chybu.

Nelze použít na deskriptor souboru vrácený funkcí fopen(), jestliže byl použit formát "http://" nebo "ftp://".

Poznámka: Argument whence byl přidán po verzi PHP 4.0 RC1.

Viz také ftell() a rewind().

fstat

(PHP 4 )

fstat -- Vrací informace o otevřeném souboru

Popis

array fstat ( int fp)

Sbírá statistiky otevřeného souboru specifikovaném deskriptorem fp. Tato funkce je podobná funkci stat(), pracuje však s deskriptorem, nikoli názvem souboru.

Vrací pole se statistikami souboru s těmito elementy:

device
inode
number of links
user id of owner
group id owner
device type if inode device *
size in bytes
time of last access
time of last modification
time of last change
blocksize for filesystem I/O *
number of blocks allocated

* - platné pouze na systémech s podporou typu st_blksize -- jinde (např. na Windows) vrací -1

Výsledek této funkce je cachován. Více detailů - viz clearstatcache().

ftell

(PHP 3, PHP 4 )

ftell -- Vrací pozici v souboru

Popis

int ftell ( int fp)

Vrací pozici v souboru odkazovaném deskriptorem fp; typicky offset ve streamu.

Pokud nastane chyba, vrací FALSE.

Deskriptor souboru musí být platný a musí ukazovat na soubor úspěšně otevřený pomocí fopen(), popen(), nebo fsockopen().

Viz také fopen(), popen(), fseek() a rewind().

ftruncate

(PHP 4 )

ftruncate -- Zkrátí soubor na danou délku

Popis

int ftruncate ( int fp, int size)

Vezme soubor specifikovaný pomocí fp a zkrátí ho na délku size. Vrací TRUE při úspěchu a FALSE při chybě.

fwrite

(PHP 3, PHP 4 )

fwrite -- Binárně bezpečný zápis do souboru

Popis

int fwrite ( int fp, string string [, int length])

fwrite() zapíše obsah řetězce string do souboru specifikovaného pomocí fp. Pokud je zde argument length, zápis skončí po zapsání length bytů nebo při dosažení konce řetězce string, podle toho, co přijde dřív.

Pozn.: pokud je dán argument length, volba magic_quotes_runtime v konfiguraci bude ignorována a nebudou odstraňována žádná lomítka z řetězce string.

Viz také fread(), fopen(), fsockopen(), popen(), a fputs().

glob

(PHP 4 CVS only)

glob -- Find pathnames matching a pattern

Description

array glob ( string pattern [, int flags])

The glob() function searches for all the pathnames matching pattern according to the rules used by the shell. No tilde expansion or parameter substitution is done.

Returns an array containing the matched files/directories or FALSE on error.

Poznámka: This function is disabled in safe mode and therefore will always return FALSE in safe mode.

Příklad 1. Convenient way how glob() can replace opendir() and friends.

foreach (glob("*.txt") as $filename) {
    echo "$filename size " . filesize($filename) . "\n";
}

This could result in the following output:

funclist.txt size 44686
funcsummary.txt size 267625
quickref.txt size 137820

Poznámka: Tato funkce nefunguje na Windows systémech

is_readable

(PHP 3, PHP 4 )

is_readable -- Zjistí, zda lze ze souboru číst

Popis

bool is_readable ( string filename)

Vrací TRUE, když soubor existuje a lze z něj číst.

Mějte na paměti, že PHP může přistupovat k souboru s právy, kterými disponuje WWW server (obvykle 'nobody'). Omezení bezpečného režimu (safe mode limitations) are not taken into account.

Výsledek této funkce je cachován. Více detailů - viz clearstatcache().

Viz také is_writable().

is_uploaded_file

(PHP 3>= 3.0.17, PHP 4 >= 4.0.3)

is_uploaded_file -- Zjistí, zda byl soubor uploadován pomocí HTTP POST

Popis

bool is_uploaded_file ( string filename)

Tato funkce je dostupná pouze na verzích PHP 3 od 3.0.16 a na verzích PHP 4 od 4.0.2.

Vrací TRUE, pokud soubor nazvaný filename byl uploadován pomocí HTTP POST. To je užitečné k ujištění se, zda se neukázněný uživatel nepokusil upravit skript tak, aby pracoval se soubory, se kterými by pracovat neměl -- například /etc/passwd.

Tento druh testů je zvláště důležitý, je-li možnost, že akce na uploadovaných souborech může zpřístupnit jejich obsah uživateli nebo jiným uživatekům tohoto systému.

Viz také move_uploaded_file(), a sekce Handling file uploads, kde je příklad jednoduchého použití.

is_writable

(PHP 4 )

is_writable -- Zjistí, zda lze do souboru zapisovat

Popis

bool is_writable ( string filename)

Vrací TRUE, když soubor existuje a lze do něj zapisovat. Název souboru (argument filename) může být název adresáře, potom se zjišťuje, zda lze do adresáře zapisovat.

Mějte na paměti, že PHP může přistupovat k souboru s právy, kterými disponuje WWW server (obvykle 'nobody'). Omezení bezpečného režimu (safe mode limitations) are not taken into account.

Výsledek této funkce je cachován. Více detailů - viz clearstatcache().

Viz také is_readable().

is_writeable

(PHP 3, PHP 4 )

is_writeable -- Tells whether the filename is writable

Description

Vrací pole se statistikami souboru s těmito elementy:

device
inode
inode protection mode
number of links
user id of owner
group id owner
device type if inode device *
size in bytes
time of last access
time of last modification
time of last change
blocksize for filesystem I/O *
number of blocks allocated

* - platné pouze na systémechs podporou typu st_blksize -- jinde (např. na Windows) vrátí -1

Výsledek této funkce je cachován. Více informací - viz clearstatcache().

mkdir

(PHP 3, PHP 4 )

mkdir -- Vytvoří adresář

Popis

int mkdir ( string pathname, int mode)

Pokusí se vytvořit adresář specifikovaný svým názvem.

Pozn.: Pravděpodobně chcete specifikovat mód jako oktalové číslo, potom by však mělo začínat nulou.

mkdir ("/path/to/my/dir", 0700);

Vrací TRUE při úspěchu a FALSE při chybě.

Viz také rmdir().

move_uploaded_file

(PHP 4 >= 4.0.3)

move_uploaded_file -- Přesune uploadovaný soubor na nové místo

Popis

bool move_uploaded_file ( string filename, string destination)

tato fuknce je dostupná pouze ve verzích PHP 3 od 3.0.16 a ve verzích PHP 4 od 4.0.2.

Tato si ověřuje, zda soubor identifikovaný názvem filename je platným uploadovaným souborem (prostřednictvím HTTP POST mechanismu poskytovaného PHP). Pokud je soubor platný, je přesunut/přejmenován na destination.

Pokud filename není platný uploadovaný soubor, funkce move_uploaded_file() nic neprovede a vrátí FALSE.

Pokud filename je platný uploadovaný soubor, ale z nějakého důvodu nemůže být přesunut, funkce move_uploaded_file() nic neprovede a vrátí FALSE. Navíc je vygenerováno varování (warning).

Tento druh testů je zvláště důležitý, je-li možnost, že akce na uploadovaných souborech může zpřístupnit jejich obsah uživateli nebo jiným uživatekům tohoto systému.

Viz také is_uploaded_file(), a sekce Handling file uploads, kde je příklad jednoduchého použití.

parse_ini_file

(PHP 4 )

parse_ini_file -- Parse a configuration file

Description

array parse_ini_file ( string filename [, bool process_sections])

parse_ini_file() loads in the ini file specified in filename, and returns the settings in it in an associative array. By setting the last process_sections parameter to TRUE, you get a multidimensional array, with the section names and settings included. The default for process_sections is FALSE

Poznámka: This function has nothing to do with the php.ini file. It is already processed, the time you run your script. This function can be used to read in your own application's configuration files.

Poznámka: If a value in the ini file contains any non-alphanumeric characters it needs to be enclosed in double-quotes (").

Poznámka: Since PHP 4.2.1 this function is also affected by safe_mode and open_basedir.

The structure of the ini file is similar to that of the php.ini's.

Varování

If the ini file you are trying to parse is malformed, PHP will exit.

Příklad 1. Contents of sample.ini

; This is a sample configuration file ; Comments start with ';', as in php.ini [first_section] one = 1 five = 5 [second_section] path = /usr/local/bin URL = "http://www.example.com/~username"

Příklad 2. parse_ini_file() example

<?php // Parse without sections $ini_array = parse_ini_file("sample.ini"); print_r($ini_array); // Parse with sections $ini_array = parse_ini_file("sample.ini", TRUE); print_r($ini_array); ?>

Would produce:

Array
(
    [one] => 1
    [five] => 5
    [path] => /usr/local/bin
    [URL] => http://www.example.com/~username
)
Array
(
    [first_section] => Array
        (
            [one] => 1
            [five] => 5
        )

    [second_section] => Array
        (
            [path] => /usr/local/bin
            [URL] => http://www.example.com/~username
        )

)

pathinfo

(PHP 4 >= 4.0.3)

pathinfo -- Returns information about a file path

Description

array pathinfo ( string path)

pathinfo() returns an associative array containing information about path. The following array elements are returned: dirname, basename and extension.

Příklad 1. pathinfo() Example

<?php $path_parts = pathinfo("/www/htdocs/index.html"); echo $path_parts["dirname"] . "\n"; echo $path_parts["basename"] . "\n"; echo $path_parts["extension"] . "\n"; ?>

Would produce:

/www/htdocs
index.html
html

pclose

(PHP 3, PHP 4 )

pclose -- Zavře procesový soubor (rouru)

Popis

readlink -- Vrací cíl symbolického odkazu

Popis

string readlink ( string path)

readlink() provádí totéž jako funkce readlink v C a vrací název souboru, na který symbolický odkaz (link) ukazuje. Při chybě vrací 0.

Viz také symlink(), readlink() a linkinfo().

Poznámka: Tato funkce nefunguje na Windows systémech

Deskriptor souboru musí být platný a musí ukazovat na soubor úspěšně otevřený pomocí fopen().

Viz také fseek() a ftell().

rmdir

(PHP 3, PHP 4 )

rmdir -- Odstraní adresář

Popis

int rmdir ( string dirname)

Pokusí se odstranit adresář specifikovaný svým názvem. Adresář musí být být prázdný a mít nastavena odpovídající oprávnění.

Nastane-li chyba, vrací 0.

Viz také mkdir().

set_file_buffer

(PHP 3>= 3.0.8, PHP 4 >= 4.0.1)

set_file_buffer -- Nastaví buffer pro soubor

Popis

int set_file_buffer ( int fp, int buffer)

Výstup pomocí fwrite() je implicitně bufferován do bufferu o velikosti 8 KB. To znamená, že když chtějí dva procesy zapisovat do téhož streamu (souboru), každý je vždy po 8 KB přerušen, aby ten druhý mohl zapisovat. Funkce set_file_buffer() nastavuje buffering pro zápis přes daný deskriptor fp na buffer bytů. Pokud je buffer roven 0, zápisy nejsou bufferovány. To zajišťuje, že všechny zápisy jsou dokončeny dřív, než ostatní procesy mohou do souboru zapisovat.

Funkce vrací 0 při úspěchu nebo EOF (konec souboru) pokud požadavek nemůže být uskutečněn.

Následující příklad demonstruje, jak používat funkci set_file_buffer() k vytvoření nebufferovaného streamu.

Příklad 1. set_file_buffer() example

$fp=fopen($file, "w"); if($fp){ set_file_buffer($fp, 0); fputs($fp, $output); fclose($fp); }

Viz také fopen(), fwrite().

stat

(PHP 3, PHP 4 )

stat -- Zjišťuje informace o souboru

Popis

array stat ( string filename)

Sbírá statistiky o souboru indentifikovaném názvem filename.

Vrací pole se statistikami souboru s těmito elementy:

device
inode
inode protection mode
number of links
user id of owner
group id owner
device type if inode device *
size in bytes
time of last access
time of last modification
time of last change
blocksize for filesystem I/O *
number of blocks allocated

* - platné pouze na systémechs podporou typu st_blksize -- jinde (např. na Windows) vrátí -1

Výsledek této funkce je cachován. Více informací - viz clearstatcache().

symlink

(PHP 3, PHP 4 )

symlink -- Vytvoří symbolický odkaz

Popis

int symlink ( string target, string link)

symlink() vytvoří symbolický odkaz (link) k existujícímu souboru target a nazve ho link.

Viz také link() -- vytváření hard linků, a readlink() společně s linkinfo().

Poznámka: Tato funkce nefunguje na Windows systémech.

tempnam

(PHP 3, PHP 4 )

tempnam -- Vytvoří soubor s unikátním názvem

Popis

string tempnam ( string dir, string prefix)

Ve specifikovaném adresáři vytvoří dočasný soubor s unikátním názvem. Pokud adresář neexistuje, tempnam() může vytvořit soubor v systémovém adresáři pro dočasné soubory.

Chování funkce tempnam() je závislé na platformě. Na Windows má parametr dir přednost před systémovou proměnnou TMP, na Linuxu má předost proměnná TMPDIR a SVR4 vždy použije parametr dir, pokud tento adresář existuje. Podívejte se do dokumentace k vašemu systému na funkci tempnam(3).

Vrací název nového dočasného souboru, při chybě pak řetězec NULL.

Příklad 1. tempnam() příklad

$tmpfname = tempnam ("/tmp", "FOO");

Poznámka: Chování této funkce bylo změněno ve verzi 4.0.3. The temporary file is also created to avoid a race condition where the file might appear in the filesystem between the time the string was generated and before the the script gets around to creating the file.

Viz také rmdir() pro mazání adresářů.

Poznámka: Tato funkce nemusí na Windows fungovat

XXXI. Forms Data Format functions

Úvod

Forms Data Format (FDF) is a format for handling forms within PDF documents. You should read the documentation at http://partners.adobe.com/asn/developer/acrosdk/forms.html for more information on what FDF is and how it is used in general.

The general idea of FDF is similar to HTML forms. The difference is basically the format how data is transmitted to the server when the submit button is pressed (this is actually the Form Data Format) and the format of the form itself (which is the Portable Document Format, PDF). Processing the FDF data is one of the features provided by the fdf functions. But there is more. One may as well take an existing PDF form and populated the input fields with data without modifying the form itself. In such a case one would create a FDF document (fdf_create()) set the values of each input field (fdf_set_value()) and associate it with a PDF form (fdf_set_file()). Finally it has to be sent to the browser with MimeType application/vnd.fdf. The Acrobat reader plugin of your browser recognizes the MimeType, reads the associated PDF form and fills in the data from the FDF document.

If you look at an FDF-document with a text editor you will find a catalogue object with the name FDF. Such an object may contain a number of entries like Fields, F, Status etc.. The most commonly used entries are Fields which points to a list of input fields, and F which contains the filename of the PDF-document this data belongs to. Those entries are referred to in the FDF documentation as /F-Key or /Status-Key. Modifying this entries is done by functions like fdf_set_file() and fdf_set_status(). Fields are modified with fdf_set_value(), fdf_set_opt() etc..

Požadavky

You must download the FDF toolkit from http://partners.adobe.com/asn/developer/acrosdk/forms.html.

Instalace

You must compile PHP with --with-fdftk[=DIR].

Poznámka: If you run into problems configuring PHP with fdftk support, check whether the header file FdfTk.h and the library libFdfTk.so are at the right place. They should be in fdftk-dir/include and fdftk-dir/lib. This will not be the case if you just unpack the FdfTk distribution.

Konfigurace běhu

Toto rozšíření nemá definováno žádné konfigurační direktivy.

Typy prostředků

Předdefinované konstanty

Tyto konstanty jsou definovány tímto rozšířením a budou k dispozici pouze tehdy, bylo-li rozšíření zkompilováno společně s PHP nebo dynamicky zavedeno za běhu.

FDFValue (integer)
FDFStatus (integer)
FDFFile (integer)
FDFID (integer)
FDFFf (integer)
FDFSetFf (integer)
FDFClearFf (integer)
FDFFlags (integer)
FDFSetF (integer)
FDFClrF (integer)
FDFAP (integer)
FDFAS (integer)
FDFAction (integer)
FDFAA (integer)
FDFAPRef (integer)
FDFIF (integer)
FDFEnter (integer)
FDFExit (integer)
FDFDown (integer)
FDFUp (integer)
FDFFormat (integer)
FDFValidate (integer)
FDFKeystroke (integer)
FDFCalculate (integer)

Příklady

The following examples shows just the evaluation of form data.

Příklad 1. Evaluating a FDF document

<?php // Save the FDF data into a temp file $fdffp = fopen("test.fdf", "w"); fwrite($fdffp, $HTTP_FDF_DATA, strlen($HTTP_FDF_DATA)); fclose($fdffp); // Open temp file and evaluate data // The pdf form contained several input text fields with the names // volume, date, comment, publisher, preparer, and two checkboxes // show_publisher and show_preparer. $fdf = fdf_open("test.fdf"); $volume = fdf_get_value($fdf, "volume"); echo "The volume field has the value '<B>$volume</B>'<BR>"; $date = fdf_get_value($fdf, "date"); echo "The date field has the value '<B>$date</B>'<BR>"; $comment = fdf_get_value($fdf, "comment"); echo "The comment field has the value '<B>$comment</B>'<BR>"; if(fdf_get_value($fdf, "show_publisher") == "On") { $publisher = fdf_get_value($fdf, "publisher"); echo "The publisher field has the value '<B>$publisher</B>'<BR>"; } else echo "Publisher shall not be shown.<BR>"; if(fdf_get_value($fdf, "show_preparer") == "On") { $preparer = fdf_get_value($fdf, "preparer"); echo "The preparer field has the value '<B>$preparer</B>'<BR>"; } else echo "Preparer shall not be shown.<BR>"; fdf_close($fdf); ?>

Obsah
fdf_add_template -- Adds a template into the FDF document
fdf_close -- Close an FDF document
fdf_create -- Create a new FDF document
fdf_get_file -- Get the value of the /F key
fdf_get_status -- Get the value of the /STATUS key
fdf_get_value -- Get the value of a field
fdf_next_field_name -- Get the next field name
fdf_open -- Open a FDF document
fdf_save -- Save a FDF document
fdf_set_ap -- Set the appearance of a field
fdf_set_encoding -- Sets FDF character encoding
fdf_set_file -- Set the value of the /F key
fdf_set_flags -- Sets a flag of a field
fdf_set_javascript_action -- Sets an javascript action of a field
fdf_set_opt -- Sets an option of a field
fdf_set_status -- Set the value of the /STATUS key
fdf_set_submit_form_action -- Sets a submit form action of a field
fdf_set_value -- Set the value of a field

fdf_add_template

(PHP 3>= 3.0.13, PHP 4 )

fdf_add_template -- Adds a template into the FDF document

Description

bool fdf_add_template ( int fdfdoc, int newpage, string filename, string template, int rename)

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

fdf_close

(PHP 3>= 3.0.6, PHP 4 )

fdf_close -- Close an FDF document

Description

bool fdf_close ( int fdf_document)

The fdf_close() function closes the FDF document.

fdf_create

(PHP 3>= 3.0.6, PHP 4 )

fdf_create -- Create a new FDF document

Description

int fdf_create ( void)

int fdf_open ( string filename)

The fdf_open() function opens a file with form data. This file must contain the data as returned from a PDF form. Currently, the file has to be created 'manually' by using fopen() and writing the content of HTTP_FDF_DATA with fwrite() into it. A mechanism like for HTML form data where for each input field a variable is created does not exist.

Příklad 1. Accessing the form data

<?php // Save the FDF data into a temp file $fdffp = fopen("test.fdf", "w"); fwrite($fdffp, $HTTP_FDF_DATA, strlen($HTTP_FDF_DATA)); fclose($fdffp); // Open temp file and evaluate data $fdf = fdf_open("test.fdf"); ... fdf_close($fdf); ?>

fdf_save

(PHP 3>= 3.0.6, PHP 4 )

fdf_save -- Save a FDF document

Description

int fdf_save ( string filename)

The fdf_save() function saves a FDF document. The FDF Toolkit provides a way to output the document to stdout if the parameter filename is '.'. This does not work if PHP is used as an apache module. In such a case one will have to write to a file and use e.g. fpassthru() to output it.

See also fdf_close() and example for fdf_create().

fdf_set_ap

(PHP 3>= 3.0.6, PHP 4 )

fdf_set_ap -- Set the appearance of a field

bool fdf_set_value ( int fdf_document, string fieldname, string value, int isName)

The fdf_set_value() function sets the value of a field. The last parameter determines if the field value is to be converted to a PDF Name (isName = 1) or set to a PDF String (isName = 0).

XXXII. FriBiDi functions

Úvod

Požadavky

Instalace

Konfigurace běhu

Typy prostředků

Předdefinované konstanty

Tyto konstanty jsou definovány tímto rozšířením a budou k dispozici pouze tehdy, bylo-li rozšíření zkompilováno společně s PHP nebo dynamicky zavedeno za běhu.

FRIBIDI_CHARSET_UTF8 (integer)
FRIBIDI_CHARSET_8859_6 (integer)
FRIBIDI_CHARSET_8859_8 (integer)
FRIBIDI_CHARSET_CP1255 (integer)
FRIBIDI_CHARSET_CP1256 (integer)
FRIBIDI_CHARSET_ISIRI_3342 (integer)

Obsah
fribidi_log2vis -- Convert a logical string to a visual one

fribidi_log2vis

(PHP 4 >= 4.0.4)

fribidi_log2vis -- Convert a logical string to a visual one

Description

string fribidi_log2vis ( string str, string direction, int charset)

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

XXXIII. FTP functions

Úvod

The functions in this extension implement client access to file servers speaking the File Transfer Protocol FTP as defined in http://www.faqs.org/rfcs/rfc959.html.

Požadavky

Tyto funkce jsou k dispozici jako součást standardního modulu, který je vždy dostupný.

Instalace

In order to use FTP functions with your PHP configuration, you should add the --enable-ftp option when installing PHP 4, and --with-ftp when using PHP 3.

Konfigurace běhu

Toto rozšíření nemá definováno žádné konfigurační direktivy.

Typy prostředků

This extension uses one resource-type, which is the link-identifier of the ftp-connection.

Předdefinované konstanty

Tyto konstanty jsou definovány tímto rozšířením a budou k dispozici pouze tehdy, bylo-li rozšíření zkompilováno společně s PHP nebo dynamicky zavedeno za běhu.

FTP_ASCII (integer)
FTP_TEXT (integer)
FTP_BINARY (integer)
FTP_IMAGE (integer)
FTP_TIMEOUT_SEC (integer)

Příklady

Příklad 1. FTP example

<?php // set up basic connection $conn_id = ftp_connect($ftp_server); // login with username and password $login_result = ftp_login($conn_id, $ftp_user_name, $ftp_user_pass); // check connection if ((!$conn_id) || (!$login_result)) { echo "FTP connection has failed!"; echo "Attempted to connect to $ftp_server for user $ftp_user_name"; die; } else { echo "Connected to $ftp_server, for user $ftp_user_name"; } // upload the file $upload = ftp_put($conn_id, $destination_file, $source_file, FTP_BINARY); // check upload status if (!$upload) { echo "FTP upload has failed!"; } else { echo "Uploaded $source_file to $ftp_server as $destination_file"; } // close the FTP stream ftp_close($conn_id); ?>

Obsah
ftp_cdup -- Changes to the parent directory
ftp_chdir -- Changes directories on a FTP server
ftp_close -- Closes an FTP connection
ftp_connect -- Opens up an FTP connection
ftp_delete -- Deletes a file on the FTP server
ftp_exec -- Request execution of a program on the FTP server
ftp_fget -- Downloads a file from the FTP server and saves to an open file
ftp_fput -- Uploads from an open file to the FTP server
ftp_get_option -- Retrieves various runtime behaviours of the current FTP stream
ftp_get -- Downloads a file from the FTP server
ftp_login -- Logs in an FTP connection
ftp_mdtm -- Returns the last modified time of the given file
ftp_mkdir -- Creates a directory
ftp_nlist -- Returns a list of files in the given directory
ftp_pasv -- Turns passive mode on or off
ftp_put -- Uploads a file to the FTP server
ftp_pwd -- Returns the current directory name
ftp_quit -- Closes an FTP connection
ftp_rawlist -- Returns a detailed list of files in the given directory
ftp_rename -- Renames a file on the FTP server
ftp_rmdir -- Removes a directory
ftp_set_option -- Set miscellaneous runtime FTP options
ftp_site -- Sends a SITE command to the server
ftp_size -- Returns the size of the given file
ftp_systype -- Returns the system type identifier of the remote FTP server

The timeout parameter specifies the timeout for all subsequent network operations. If omitted, the default value is 90 seconds. The timeout can be changed and queried anytime with ftp_set_option() and ftp_get_option().

Poznámka: This parameter is only available in CVS.

ftp_delete

(PHP 3>= 3.0.13, PHP 4 )

ftp_delete -- Deletes a file on the FTP server

Description

bool ftp_delete ( resource ftp_stream, string path)

ftp_delete() deletes the file specified by path from the FTP server.

Returns TRUE on success, FALSE on error.

ftp_exec

(PHP 4 >= 4.0.3)

ftp_exec -- Request execution of a program on the FTP server

mixed ftp_get_option ( resource ftp_stream, int option)

Poznámka: This function is only available in CVS.

Returns the value on success, or FALSE if the given option is not supported. In the latter case, a warning message is also thrown.

This function returns the value for the requested option from the specified ftp_stream . Currently, the following options are supported:

Tabulka 1. Supported runtime FTP options

int ftp_mdtm ( resource ftp_stream, string remote_file)

ftp_mdtm() checks the last-modified time for a file, and returns it as a UNIX timestamp. If an error occurs, or the file does not exist, -1 is returned. Note that not all servers support this feature.

Returns a UNIX timestamp on success, or -1 on error.

Poznámka: ftp_mdtm() does not work with directories.

ftp_mkdir

(PHP 3>= 3.0.13, PHP 4 )

ftp_mkdir -- Creates a directory

Description

string ftp_mkdir ( resource ftp_stream, string directory)

Creates the specified directory.

Returns the newly created directory name on success, FALSE on error.

ftp_nlist

(PHP 3>= 3.0.13, PHP 4 )

ftp_nlist -- Returns a list of files in the given directory

Description

array ftp_nlist ( resource ftp_stream, string directory)

Returns an array of filenames from the specified directory on success, FALSE on error.

ftp_pasv

(PHP 3>= 3.0.13, PHP 4 )

ftp_pasv -- Turns passive mode on or off

Description

bool ftp_pasv ( resource ftp_stream, bool pasv)

ftp_pasv() turns on passive mode if the pasv parameter is TRUE (it turns off passive mode if pasv is FALSE.) In passive mode, data connections are initiated by the client, rather than by the server.

Returns TRUE on success, FALSE on error.

ftp_put

(PHP 3>= 3.0.13, PHP 4 )

ftp_put -- Uploads a file to the FTP server

Description

bool ftp_put ( resource ftp_stream, string remote_file, string local_file, int mode)

ftp_put() stores local_file on the FTP server, as remote_file. The transfer mode specified must be either FTP_ASCII or FTP_BINARY.

bool ftp_rename ( resource ftp_stream, string from, string to)

ftp_rename() renames the file or directory currently named from to the new name to, on the FTP stream ftp_stream.

Returns TRUE on success, FALSE on error.

ftp_rmdir

(PHP 3>= 3.0.13, PHP 4 )

ftp_rmdir -- Removes a directory

Description

bool ftp_rmdir ( resource ftp_stream, string directory)

Removes the specified directory.

Returns TRUE on success, FALSE on error.

ftp_set_option

(PHP 4 >= 4.2.0)

ftp_set_option -- Set miscellaneous runtime FTP options

Description

bool ftp_set_option ( resource ftp_stream, int option, mixed value)

Poznámka: This function is only available in CVS.

Returns TRUE if the option could be set; FALSE if not. A warning message will be thrown if the option is not supported or the passed value doesn't match the expected value for the given option.

This function controls various runtime options for the specified FTP stream. The value parameter depends on which option parameter is chosen to be altered. Currently, the following options are supported:

string ftp_systype ( resource ftp_stream)

Returns the remote system type, or FALSE on error.

XXXIV. Funkce pro práci s funkcemi

Všechny tyto funkce pokrývají různé aspekty práce s funkcemi.

Obsah
call_user_func_array -- Call a user function given with an array of parameters
call_user_func -- Zavolat uživatelskou funkci určenou prvním argumentem
create_function -- Vytvořit anonymní (lambda-style) funkci
func_get_arg -- Vrátit položku ze seznamu argumentů
func_get_args -- Vrátit pole obsahující seznam argumentů funkce
func_num_args -- Vrátit počet argumentů předaných funkci
function_exists -- Vrátit TRUE, pokud je daná funkce definována
get_defined_functions -- Returns an array of all defined functions
register_shutdown_function -- Zaregistrovat funkci pro provedení při ukončení běhu
register_tick_function -- Register a function for execution on each tick
unregister_tick_function -- De-register a function for execution on each tick

call_user_func_array

(PHP 4 >= 4.0.4)

call_user_func_array -- Call a user function given with an array of parameters

Description

mixed call_user_func_array ( string function_name [, array paramarr])

Call a user defined function given by function_name, with the parameters in paramarr. For example:

function debug($var, $val)
    echo "***DEBUGGING\nVARIABLE: $var\nVALUE:";
    if (is_array($val) || is_object($val) || is_resource($val))
        print_r($val);
    else
        echo "\n$val\n";
    echo "***\n";
}

$c = mysql_connect();
$host = $_SERVER["SERVER_NAME"];

call_user_func_array ('debug', array("host", $host));
call_user_func_array ('debug', array("c", $c));
call_user_func_array ('debug', array("_POST", $_POST));

Poznámka: This function was added to the CVS code after release of PHP 4.0.4pl1

call_user_func

(PHP 3>= 3.0.3, PHP 4 )

call_user_func -- Zavolat uživatelskou funkci určenou prvním argumentem

Popis

mixed call_user_func ( string function_name [, mixed parameter [, mixed ...]])

Zavolá uživatelsky definouvanou funkci určenou argumentem function_name. Zvažte následující ukázku:

function barber ($type) {
    print "You wanted a $type haircut, no problem";
}
call_user_func ('barber', "mushroom");
call_user_func ('barber', "shave");

create_function

(PHP 4 >= 4.0.1)

create_function -- Vytvořit anonymní (lambda-style) funkci

Popis

string create_function ( string args, string code)

Z předaných argumentů vytvoří anonymní funkci, a vrátí unikátní název této funkce. args se obvykle předává jako string v jednoduchých uvozovkách, a doporučujeme to i pro code. Důvodem pro jednoduché uvozovky je ochrana názvů proměnných před parsováním, pokud použijete dvojité uvozovky, budete muset oescapovat názvy proměnných, např. \$avar.

Tuto funkci můžete (například) použít k vytvoření funkce z dat shromážděných za běhu programu:

Příklad 1. Vytvoření anonymní funkce pomocí create_function()

$newfunc = create_function('$a,$b','return "ln($a) + ln($b) = ".log($a * $b);'); echo "New anonymous function: $newfunc\n"; echo $newfunc(2,M_E)."\n"; // výstup // New anonymous function: lambda_1 // ln(2) + ln(2.718281828459) = 1.6931471805599
Nebo třeba k vytvoření obecného handleru, který na předané argumenty aplikuje sadu operací:

Příklad 2. Vytvoření obecné zpracující funkce pomocí create_function()

function process($var1, $var2, $farr) { for ($f=0; $f < count($farr); $f++) echo $farr[$f]($var1,$var2)."\n"; } // create a bunch of math functions $f1 = 'if ($a >=0) {return "b*a^2 = ".$b*sqrt($a);} else {return false;}'; $f2 = "return \"min(b^2+a, a^2,b) = \".min(\$a*\$a+\$b,\$b*\$b+\$a);"; $f3 = 'if ($a > 0 && $b != 0) {return "ln(a)/b = ".log($a)/$b;} else {return false;}'; $farr = array( create_function('$x,$y', 'return "some trig: ".(sin($x) + $x*cos($y));'), create_function('$x,$y', 'return "a hypotenuse: ".sqrt($x*$x + $y*$y);'), create_function('$a,$b', $f1), create_function('$a,$b', $f2), create_function('$a,$b', $f3) ); echo "\nUsing the first array of anonymous functions\n"; echo "parameters: 2.3445, M_PI\n"; process(2.3445, M_PI, $farr); // now make a bunch of string processing functions $garr = array( create_function('$b,$a','if (strncmp($a,$b,3) == 0) return "** \"$a\" '. 'and \"$b\"\n** Look the same to me! (looking at the first 3 chars)";'), create_function('$a,$b','; return "CRCs: ".crc32($a)." , ".crc32(b);'), create_function('$a,$b','; return "similar(a,b) = ".similar_text($a,$b,&$p)."($p%)";') ); echo "\nUsing the second array of anonymous functions\n"; process("Twas brilling and the slithy toves", "Twas the night", $garr);
když spustíte výšeuvedený kód, výstup bude:

Using the first array of anonymous functions
parameters: 2.3445, M_PI
some trig: -1.6291725057799
a hypotenuse: 3.9199852871011
b*a^2 = 4.8103313314525
min(b^2+a, a^2,b) = 8.6382729035898
ln(a/b) = 0.27122299212594

Using the second array of anonymous functions
** "Twas the night" and "Twas brilling and the slithy toves"
** Look the same to me! (looking at the first 3 chars)
CRCs: -725381282 , 1908338681
similar(a,b) = 11(45.833333333333%)

Ale zřejmě nejběžnějším využitím lambda-style (anonymních) funkcí je tvorba callback funkcí, např. pro použití v array_walk() nebo usort()

Příklad 3. Využití anonymních funkcí jako callback funkcí

$av = array("the ","a ","that ","this ");
array_walk($av, create_function('&$v,$k','$v = $v."mango";'));
print_r($av);  // for PHP 3 use var_dump()
// outputs:
// Array
// (
//   [0] => the mango
//   [1] => a mango
//   [2] => that mango
//   [3] => this mango
// )

// an array of strings ordered from shorter to longer
$sv = array("small","larger","a big string","it is a string thing");
print_r($sv);
// outputs:
// Array
// (
//   [0] => small
//   [1] => larger
//   [2] => a big string
//   [3] => it is a string thing
// )

// sort it from longer to shorter
usort($sv, create_function('$a,$b','return strlen($b) - strlen($a);'));
print_r($sv);
// outputs:
// Array
// (
//   [0] => it is a string thing
//   [1] => a big string
//   [2] => larger
//   [3] => small
// )

func_get_arg

(PHP 4 )

func_get_arg -- Vrátit položku ze seznamu argumentů

Popis

mixed func_get_arg ( int arg_num)

Vrací argument, který je na arg_num-té pozici v seznamu argumentů užiavtelsky definované funkce. Argumenty funkcí se počítají od nuly. func_get_arg() při volání mimo definici funkce generuje varování.

Pokud je arg_num větší než počet skutečně předaných argumentů, vygeneruje varování a vrátí FALSE.

<?php
function foo() {
     $numargs = func_num_args();
     echo "Number of arguments: $numargs<br>\n";
     if ($numargs >= 2) {
     echo "Second argument is: " . func_get_arg (1) . "<br>\n";
     }
}

foo (1, 2, 3);
?>

func_get_arg() se dá použít ve spojení s func_num_args() a func_get_args() k tvorbě uživatelsky definovaných funkcí, které přijímají proměnný počet argumentů.

Poznámka: Tato funkce byla přidána v PHP 4.

func_get_args

(PHP 4 )

func_get_args -- Vrátit pole obsahující seznam argumentů funkce

Popis

array func_get_args ( void )

Vrací pole, jehož každý prvek je odpovídající položkou seznamu argumentů současné uživatelsky definované funkce. func_get_args() při volání mimo definici funkce generuje varování.

<?php
function foo() {
    $numargs = func_num_args();
    echo "Number of arguments: $numargs<br>\n";
    if ($numargs >= 2) {
    echo "Second argument is: " . func_get_arg (1) . "<br>\n";
    }
    $arg_list = func_get_args();
    for ($i = 0; $i < $numargs; $i++) {
    echo "Argument $i is: " . $arg_list[$i] . "<br>\n";
    }
}

foo (1, 2, 3);
?>

func_get_args() se dá použít ve spojení s func_num_args() a func_get_arg() k tvorbě uživatelsky definovaných funkcí, které přijímají proměnny počet argumentů.

Poznámka: Tato funkce byla přidána v PHP 4.

func_num_args

(PHP 4 )

func_num_args -- Vrátit počet argumentů předaných funkci

Popis

int func_num_args ( void )

Vrací počet argumentů předaných současné uživatelsky definované funkci. func_num_args() pri volání mimo definici funkce generuje warning. definition.

<?php
function foo() {
    $numargs = func_num_args();
    echo "Number of arguments: $numargs\n";
}

foo (1, 2, 3);    // Prints 'Number of arguments: 3'
?>

func_num_args() se dá použit ve spojení s func_get_arg() a func_get_args() k tvorbě uživatelsky definovaných funkcí, které přijímají proměnný počet argumentů.

Poznámka: Tato funkce byla přidána v PHP 4.

function_exists

(PHP 3>= 3.0.7, PHP 4 )

function_exists -- Vrátit TRUE, pokud je daná funkce definována

Popis

bool function_exists ( string function_name)

Ověří přítomnost funkce function_name v seznamu definovaných funkcí. Pokud daná funkce existuje, vrací TRUE, jinak FALSE.

if (function_exists('imap_open')) {
    echo "IMAP functions are available.<br>\n";
} else {
    echo "IMAP functions are not available.<br>\n";
}

Pozn.: název funkce může existovat i v případě, že je samotná funkce nepoužitelná kvůli konfiguraci nebo volbám zadaným při kompilaci.

Viz také method_exists().

get_defined_functions

(PHP 4 >= 4.0.4)

get_defined_functions -- Returns an array of all defined functions

Description

array get_defined_functions ( void)

This function returns an multidimensional array containing a list of all defined functions, both built-in (internal) and user-defined. The internal functions will be accessible via $arr["internal"], and the user defined ones using $arr["user"] (see example below).

function myrow($id, $data) {
    return "<tr><th>$id</th><td>$data</td></tr>\n";
}

$arr = get_defined_functions();

print_r($arr);

Will output something along the lines of:

Array
(
    [internal] => Array
        (
            [0] => zend_version
            [1] => func_num_args
            [2] => func_get_arg
            [3] => func_get_args
            [4] => strlen
            [5] => strcmp
            [6] => strncmp
            ...
            [750] => bcscale
            [751] => bccomp
        )

    [user] => Array
        (
            [0] => myrow
        )

)

register_shutdown_function

(PHP 3>= 3.0.4, PHP 4 )

register_shutdown_function -- Zaregistrovat funkci pro provedení při ukončení běhu

Popis

int register_shutdown_function ( string func)

Zaregistruje funkci udanou v func pro provedení po dokončení běhu skriptu.

Běžné problémy:

Jelikož tato funkce nemůže poslat browseru žádný výstup, nebudete ji moci debugovat pomocí příkazů jako print() nebo echo().

register_tick_function

(PHP 4 >= 4.0.3)

register_tick_function -- Register a function for execution on each tick

Description

void register_tick_function ( string func [, mixed arg])

Registers the function named by func to be executed when a tick is called.

unregister_tick_function

(PHP 4 >= 4.0.3)

unregister_tick_function -- De-register a function for execution on each tick

Description

void unregister_tick_function ( string func [, mixed arg])

De-registers the function named by func so it is no longer executed when a tick is called.

XXXV. GNU Gettext

Gettext funkce implementujíc NLS (Native Language Support) API, která se dá použít k internacionalizaci vašich PHP aplikací. Důkladné vysvětlení těchto funkcí viz dokumentaci GNU Gettext.

Obsah
bind_textdomain_codeset -- Specify the character encoding in which the messages from the DOMAIN message catalog will be returned
bindtextdomain -- Nastavit cestu pro doménu
dcgettext -- Změnit doménu pro jediné vyhledání
dcngettext -- Plural version of dcgettext
dgettext -- Změnit současnou doménu
dngettext -- Plural version of dgettext
gettext -- Vyhledat zprávu v současné doméně
ngettext -- Plural version of gettext
textdomain -- Nastavit výchozí doménu

bind_textdomain_codeset

(PHP 4 >= 4.2.0)

bind_textdomain_codeset -- Specify the character encoding in which the messages from the DOMAIN message catalog will be returned

Description

string bind_textdomain_codeset ( string domain, string codeset)

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

bindtextdomain

(PHP 3>= 3.0.7, PHP 4 )

bindtextdomain -- Nastavit cestu pro doménu

Popis

string bindtextdomain ( string domain, string directory)

Funkce bindtextdomain() nastaví cestu pro doménu.

dcgettext

(PHP 3>= 3.0.7, PHP 4 )

dcgettext -- Změnit doménu pro jediné vyhledání

<?php
// Set language to German
putenv ("LANG=de");

// Specify location of translation tables
bindtextdomain ("myPHPApp", "./locale");

// Choose domain
textdomain ("myPHPApp");

// Print a test message
print (gettext ("Vítejte v mé PHP Aplikaci"));
?>

ngettext

(PHP 4 >= 4.2.0)

ngettext -- Plural version of gettext

Description

string ngettext ( string msgid1, string msgid2, int n)

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

textdomain

(PHP 3>= 3.0.7, PHP 4 )

textdomain -- Nastavit výchozí doménu

Popis

string textdomain ( string text_domain)

Tato funkce nastaví doménu pro vyhledávání při volání funkce gettext(), obvykle pojmenovanou podle aplikace. Vrátí předchozí výchozí doménu. Při volání bez argumentů vrátí současné nastavení, aniž by jej měnila.

XXXVI. GMP functions

Úvod

These functions allow you to work with arbitrary-length integers using the GNU MP library.

These functions have been added in PHP 4.0.4.

Poznámka: Most GMP functions accept GMP number arguments, defined as resource below. However, most of these functions will also accept numeric and string arguments, given that it is possible to convert the latter to a number. Also, if there is a faster function that can operate on integer arguments, it would be used instead of the slower function when the supplied arguments are integers. This is done transparently, so the bottom line is that you can use integers in every function that expects GMP number. See also the gmp_init() function.

Varování

If you want to explicitly specify a large integer, specify it as a string. If you don't do that, PHP will interpret the integer-literal first, possibly resulting in loss of precision, even before GMP comes into play.

Požadavky

You can download the GMP library from http://www.swox.com/gmp/. This site also has the GMP manual available.

You will need GMP version 2 or better to use these functions. Some functions may require more recent version of the GMP library.

Instalace

In order to have these functions available, you must compile PHP with GMP support by using the --with-gmp option.

Konfigurace běhu

Toto rozšíření nemá definováno žádné konfigurační direktivy.

Typy prostředků

Toto rezšíření nemá definován žádný typ prostředku (resource).

Předdefinované konstanty

Tyto konstanty jsou definovány tímto rozšířením a budou k dispozici pouze tehdy, bylo-li rozšíření zkompilováno společně s PHP nebo dynamicky zavedeno za běhu.

GMP_ROUND_ZERO (integer)
GMP_ROUND_PLUSINF (integer)
GMP_ROUND_MINUSINF (integer)

Příklady

Příklad 1. Factorial function using GMP

<?php function fact ($x) { if ($x <= 1) return 1; else return gmp_mul ($x, fact ($x-1)); } print gmp_strval (fact (1000)) . "\n"; ?>

This will calculate factorial of 1000 (pretty big number) very fast.

Viz také

More mathmatical functions can be found in the sections BCMath Arbitrary Precision Mathematics Functions and Mathematical Functions.

Obsah
gmp_abs -- Absolute value
gmp_add -- Add numbers
gmp_and -- Logical AND
gmp_clrbit -- Clear bit
gmp_cmp -- Compare numbers
gmp_com -- Calculates one's complement of a
gmp_div_q -- Divide numbers
gmp_div_qr -- Divide numbers and get quotient and remainder
gmp_div_r -- Remainder of the division of numbers
gmp_div -- Divide numbers
gmp_divexact -- Exact division of numbers
gmp_fact -- Factorial
gmp_gcd -- Calculate GCD
gmp_gcdext -- Calculate GCD and multipliers
gmp_hamdist -- Hamming distance
gmp_init -- Create GMP number
gmp_intval -- Convert GMP number to integer
gmp_invert -- Inverse by modulo
gmp_jacobi -- Jacobi symbol
gmp_legendre -- Legendre symbol
gmp_mod -- Modulo operation
gmp_mul -- Multiply numbers
gmp_neg -- Negate number
gmp_or -- Logical OR
gmp_perfect_square -- Perfect square check
gmp_popcount -- Population count
gmp_pow -- Raise number into power
gmp_powm -- Raise number into power with modulo
gmp_prob_prime -- Check if number is "probably prime"
gmp_random -- Random number
gmp_scan0 -- Scan for 0
gmp_scan1 -- Scan for 1
gmp_setbit -- Set bit
gmp_sign -- Sign of number
gmp_sqrt -- Square root
gmp_sqrtrm -- Square root with remainder
gmp_strval -- Convert GMP number to string
gmp_sub -- Subtract numbers
gmp_xor -- Logical XOR

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

gmp_div_q

(PHP 4 >= 4.0.4)

gmp_div_q -- Divide numbers

Description

resource gmp_div_q ( resource a, resource b [, int round])

Divides a by b and returns the integer result. The result rounding is defined by the round, which can have the following values:

GMP_ROUND_ZERO: The result is truncated towards 0.
GMP_ROUND_PLUSINF: The result is rounded towards +infinity.
GMP_ROUND_MINUSINF: The result is rounded towards -infinity.

This function can also be called as gmp_div().

gmp_div_qr

(PHP 4 >= 4.0.4)

gmp_div_qr -- Divide numbers and get quotient and remainder

Description

array gmp_div_qr ( resource n, resource d [, int round])

The function divides n by d and returns array, with the first element being [n/d] (the integer result of the division) and the second being (n - [n/d] * d) (the remainder of the division).

See the gmp_div_q() function for description of the round argument.

Příklad 1. Division of GMP numbers

<?php $a = gmp_init ("0x41682179fbf5"); $res = gmp_div_qr ($a, "0xDEFE75"); printf("Result is: q - %s, r - %s", gmp_strval ($res[0]), gmp_strval ($res[1])); ?>

gmp_div_r

(PHP 4 >= 4.0.4)

gmp_div_r -- Remainder of the division of numbers

Description

Příklad 1. Creating GMP number

<?php $a = gmp_init (123456); $b = gmp_init ("0xFFFFDEBACDFEDF7200"); ?>

Poznámka: It is not necessary to call this function if you want to use integer or string in place of GMP number in GMP functions, like gmp_add(). Function arguments are automatically converted to GMP numbers, if such conversion is possible and needed, using the same rules as gmp_init().

gmp_intval

(PHP 4 >= 4.0.4)

gmp_intval -- Convert GMP number to integer

Description

bool gmp_perfect_square ( resource a)

string gmp_strval ( resource gmpnumber [, int base])

Convert GMP number to string representation in base base. The default base is 10. Allowed values for the base are from 2 to 36.

Příklad 1. Converting a GMP number to a string

<?php $a = gmp_init("0x41682179fbf5"); printf ("Decimal: %s, 36-based: %s", gmp_strval($a), gmp_strval($a,36)); ?>

gmp_sub

(PHP 4 >= 4.0.4)

gmp_sub -- Subtract numbers

Description

resource gmp_sub ( resource a, resource b)

Subtracts b from a and returns the result.

gmp_xor

(PHP 4 >= 4.0.4)

gmp_xor -- Logical XOR

Description

resource gmp_xor ( resource a, resource b)

Calculates logical exclusive OR (XOR) of two GMP numbers.

XXXVII. HTTP funkce

Tyto funkce vám umožňují manipulovat výstupem posílaným zpět browseru přímo na úrovni HTTP protokolu.

Obsah
header -- Poslat HTTP hlavičku
headers_sent -- Vrátit TRUE, pokud byly odeslány hlavičky
setcookie -- Poslat cookie

header

(PHP 3, PHP 4 )

header -- Poslat HTTP hlavičku

Popis

int header ( string string)

Funkce header() se používá na začátku HTML souboru k odeslání HTTP hlaviček. Více informací o HTTP hlavičkách viz Specifikace HTTP 1.1. Poznámka: Pamatujte, že funkce header() musí být volána dříve než se odešle jakýkoliv normální výstup, ať už normálními HTML tagy, nebo z PHP. Velmi obvyklou chybou je načítat kód pomocí include() nebo auto_prepend a mít v tomto kódu prázdné řádky, které způsobí odeslání výstupu před voláním funkce header().

Existují dva zvláštní případy volání funkce header(). Prvním je hlavička "Location". Ta nejenže odešle hlavičku browseru, ale navíc i vrátí Apachi stavový kód REDIRECT. Z pohledu autora skriptu by to nemělo být důležité, ale je to důležité pro lidi, kteří rozumí vnitřnostem Apache.

header ("Location: http://www.php.net"); /* Přesměrujeme browser
                                            na web site PHP */
exit;                 /* Pojistíme si, že se další kód nevykoná po
                         přesměrování. */

Druhým zvláštním případem jsou všechny hlavičky začínající řetězcem "HTTP/" (velikost písmen nehraje roli). Například, pokud direktiva ErrorDocument 404 vašeho Apache ukazuje na PHP skript, nebylo by od věci, kdyby skutečně generoval 404. První věcí, kterou byste v tomto skriptu měli udělat tudíz bude:

header ("HTTP/1.0 404 Not Found");

PHP skripty často generují dynamické HTML, které nesmí být cachováno uživatelským browserem, ani žýdnými proxynami mezi serverem a uživatelským browserem. Mnoho proxyn a klientů se dá donutit k vypnutí cachování s pomocí

header ("Expires: Mon, 26 Jul 1997 05:00:00 GMT");    // datum v minulosti
header ("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT");
                                                      // vždy upraven
header ("Cache-Control: no-cache, must-revalidate");  // HTTP/1.1
header ("Pragma: no-cache");                          // HTTP/1.0

Viz také headers_sent()

headers_sent

(PHP 3>= 3.0.8, PHP 4 )

headers_sent -- Vrátit TRUE, pokud byly odeslány hlavičky

Popis

boolean headers_sent ( void)

Tato funkce vrátí TRUE, pokud už byly HTTP hlavičky odeslány, jinak FALSE.

Viz také header()

setcookie

(PHP 3, PHP 4 )

setcookie -- Poslat cookie

Popis

int setcookie ( string name [, string value [, int expire [, string path [, string domain [, int secure]]]]])

setcookie() definuje cookie, který se pošle spolu s hlavičkami. Cookies se musí odeslat jako první ze všech HTTP hlaviček (to je omezení cookies, ne PHP). Volání této funkce musíte tudíž umístit před <html> či <head> tagy.

Všechny argumenty kromě argumentu name jsou nepovinné. Pokud je přítomný pouze argument name, u klienta se smaže cookie tohoto jména. Kterýkoliv argument můžete také nahradit prázdným řetězcem (""), čímž tento argument přeskočíte. Argumenty expire a secure jsou celočíselné a nedají se přeskočit prázdným řetězcem. Místo toho použijte nulu (0). Argument expire je běžné Unixové celočíselné vyjádření času, jak je vrací funkce time() či mktime(). Argument secure indikuje, že by se tento cookie měl přenášet pouze po zabezpečeném HTTPS spojení.

Běžné zádrhele:

Cookies jsou přístupné až při dalším načtení stránky, na které přístupné být mají.
Cookies se musí mazat se stejnými parametry, se kterými byly odeslány.

V PHP 3 se vícenásobná volání setcookie() v jednom skriptu provedou v opačném pořadí. Pokud se pokoušíte smazat jeden cookie pře odesláním jiného, měli byste umístit vložení před smazání. V PHP 4 se vícenásobná volání setcookie() provedou v tom pořadí, jak jsou volána.

Několik příkladů, jak posílat cookies:

Příklad 1. Ukázky odeslání cookies pomocí setcookie()

setcookie ("TestCookie", "Zkušební hodnota"); setcookie ("TestCookie", $value,time()+3600); /* vyprší za hodinu */ setcookie ("TestCookie", $value,time()+3600, "/~rasmus/", ".utoronto.ca", 1);

Následují příklady mazání cookies z předchozí ukázky:

Příklad 2. Ukázky mazání cookies pomocí setcookie()

setcookie ("TestCookie"); // nastaví dobu vypršení na čas před hodinou setcookie ("TestCookie", "", time() - 3600); setcookie ("TestCookie", "", time() - 3600, "/~rasmus/", ".utoronto.ca", 1);
Při mazání cookie byste se měli ujistit, že je doba vypršení v minulosti, čímž se v browseru zapne mechanismus odstranění cookie.

Všimněte si, že hodnotová část cookie se při odeslání cookie automaticky url-zakóduje, a při přijetí se automaticky dekóduje a přiřadí proměnné stejného jména, jako je jméno cookie. Pokud chcete vidět obsah našeho zkušebního cookie, použijte některý z následujících příkladů:

echo $TestCookie;
echo $HTTP_COOKIE_VARS["TestCookie"];

Cookies obsahující pole můžete také odeslat tak, že za název cookie napíšete hranaté závorky. Účinkem tohoto je odeslání tolika cookies, kolik má vaše pole prvků, ale když váš skript tyto cookies přijme, hodnoty se umístí v poli stejného jména, jako jsou vaše cookies:

setcookie ("cookie[three]", "cookiethree");
setcookie ("cookie[two]", "cookietwo");
setcookie ("cookie[one]", "cookieone");
if (isset ($cookie)) {
    while (list ($name, $value) = each ($cookie)) {
        echo "$name == $value<br>\n";
    }
}

Více informací o cookies viz specifikace cookies na http://www.netscape.com/newsref/std/cookie_spec.html.

Microsoft Internet Explorer 4 se Service Packem 1 zpracovává chybně cookies, které mají nastavený argument path.

Netscape Communicator 4.05 a Microsoft Internet Explorer 3.x zřejmě nezpracují cookies správně, pokud nejsou nastaveny argumenty path a time.

XXXVIII. Hyperwave functions

Introduction

Hyperwave has been developed at IICM in Graz. It started with the name Hyper-G and changed to Hyperwave when it was commercialised (If I remember properly it was in 1996).

Hyperwave is not free software. The current version, 4.1, is available at http://www.hyperwave.com/. A time limited version can be ordered for free (30 days).

Hyperwave is an information system similar to a database (HIS, Hyperwave Information Server). Its focus is the storage and management of documents. A document can be any possible piece of data that may as well be stored in file. Each document is accompanied by its object record. The object record contains meta data for the document. The meta data is a list of attributes which can be extended by the user. Certain attributes are always set by the Hyperwave server, other may be modified by the user. An attribute is a name/value pair of the form name=value. The complete object record contains as many of those pairs as the user likes. The name of an attribute does not have to be unique, e.g. a title may appear several times within an object record. This makes sense if you want to specify a title in several languages. In such a case there is a convention, that each title value is preceded by the two letter language abbreviation followed by a colon, e.g. 'en:Title in English' or 'ge:Titel in deutsch'. Other attributes like a description or keywords are potential candidates. You may also replace the language abbreviation by any other string as long as it separated by colon from the rest of the attribute value.

Each object record has native a string representation with each name/value pair separated by a newline. The Hyperwave extension also knows a second representation which is an associated array with the attribute name being the key. Multilingual attribute values itself form another associated array with the key being the language abbreviation. Actually any multiple attribute forms an associated array with the string left to the colon in the attribute value being the key. (This is not fully implemented. Only the attributes Title, Description and Keyword are treated properly yet.)

Besides the documents, all hyper links contained in a document are stored as object records as well. Hyper links which are in a document will be removed from it and stored as individual objects, when the document is inserted into the database. The object record of the link contains information about where it starts and where it ends. In order to gain the original document you will have to retrieve the plain document without the links and the list of links and reinsert them (The functions hw_pipedocument() and hw_gettext() do this for you. The advantage of separating links from the document is obvious. Once a document to which a link is pointing to changes its name, the link can easily be modified accordingly. The document containing the link is not affected at all. You may even add a link to a document without modifying the document itself.

Saying that hw_pipedocument() and hw_gettext() do the link insertion automatically is not as simple as it sounds. Inserting links implies a certain hierarchy of the documents. On a web server this is given by the file system, but Hyperwave has its own hierarchy and names do not reflect the position of an object in that hierarchy. Therefore creation of links first of all requires a mapping from the Hyperwave hierarchy and namespace into a web hierarchy respective web namespace. The fundamental difference between Hyperwave and the web is the clear distinction between names and hierarchy in Hyperwave. The name does not contain any information about the objects position in the hierarchy. In the web the name also contains the information on where the object is located in the hierarchy. This leads to two possibles ways of mapping. Either the Hyperwave hierarchy and name of the Hyperwave object is reflected in the URL or the name only. To make things simple the second approach is used. Hyperwave object with name 'my_object' is mapped to 'http://host/my_object' disregarding where it resides in the Hyperwave hierarchy. An object with name 'parent/my_object' could be the child of 'my_object' in the Hyperwave hierarchy, though in a web namespace it appears to be just the opposite and the user might get confused. This can only be prevented by selecting reasonable object names.

Having made this decision a second problem arises. How do you involve PHP? The URL http://host/my_object will not call any PHP script unless you tell your web server to rewrite it to e.g. 'http://host/php3_script/my_object' and the script 'php3_script' evaluates the $PATH_INFO variable and retrieves the object with name 'my_object' from the Hyperwave server. Their is just one little drawback which can be fixed easily. Rewriting any URL would not allow any access to other document on the web server. A PHP script for searching in the Hyperwave server would be impossible. Therefore you will need at least a second rewriting rule to exclude certain URLS like all e.g. starting with http://host/Hyperwave. This is basically sharing of a namespace by the web and Hyperwave server.

Based on the above mechanism links are insert into documents.

It gets more complicated if PHP is not run as a server module or CGI script but as a standalone application e.g. to dump the content of the Hyperwave server on a CD-ROM. In such a case it makes sense to retain the Hyperwave hierarchy and map in onto the file system. This conflicts with the object names if they reflect its own hierarchy (e.g. by choosing names including '/'). Therefore '/' has to be replaced by another character, e.g. '_'. to be continued.

The network protocol to communicate with the Hyperwave server is called HG-CSP (Hyper-G Client/Server Protocol). It is based on messages to initiate certain actions, e.g. get object record. In early versions of the Hyperwave Server two native clients (Harmony, Amadeus) were provided for communication with the server. Those two disappeared when Hyperwave was commercialised. As a replacement a so called wavemaster was provided. The wavemaster is like a protocol converter from HTTP to HG-CSP. The idea is to do all the administration of the database and visualisation of documents by a web interface. The wavemaster implements a set of placeholders for certain actions to customise the interface. This set of placeholders is called the PLACE Language. PLACE lacks a lot of features of a real programming language and any extension to it only enlarges the list of placeholders. This has led to the use of JavaScript which IMO does not make life easier.

Adding Hyperwave support to PHP should fill in the gap of a missing programming language for interface customisation. It implements all the messages as defined by the HG-CSP but also provides more powerful commands to e.g. retrieve complete documents.

Hyperwave has its own terminology to name certain pieces of information. This has widely been taken over and extended. Almost all functions operate on one of the following data types.

object ID: An unique integer value for each object in the Hyperwave server. It is also one of the attributes of the object record (ObjectID). Object ids are often used as an input parameter to specify an object.
object record: A string with attribute-value pairs of the form attribute=value. The pairs are separated by a carriage return from each other. An object record can easily be converted into an object array with hw_object2array(). Several functions return object records. The names of those functions end with obj.
object array: An associated array with all attributes of an object. The key is the attribute name. If an attribute occurs more than once in an object record it will result in another indexed or associated array. Attributes which are language depended (like the title, keyword, description) will form an associated array with the key set to the language abbreviation. All other multiple attributes will form an indexed array. PHP functions never return object arrays.
hw_document: This is a complete new data type which holds the actual document, e.g. HTML, PDF etc. It is somewhat optimised for HTML documents but may be used for any format.

Several functions which return an array of object records do also return an associated array with statistical information about them. The array is the last element of the object record array. The statistical array contains the following entries:

Hidden: Number of object records with attribute PresentationHints set to Hidden.
CollectionHead: Number of object records with attribute PresentationHints set to CollectionHead.
FullCollectionHead: Number of object records with attribute PresentationHints set to FullCollectionHead.
CollectionHeadNr: Index in array of object records with attribute PresentationHints set to CollectionHead.
FullCollectionHeadNr: Index in array of object records with attribute PresentationHints set to FullCollectionHead.
Total: Total: Number of object records.

Integration with Apache

The Hyperwave extension is best used when PHP is compiled as an Apache module. In such a case the underlying Hyperwave server can be hidden from users almost completely if Apache uses its rewriting engine. The following instructions will explain this.

Since PHP with Hyperwave support built into Apache is intended to replace the native Hyperwave solution based on Wavemaster I will assume that the Apache server will only serve as a Hyperwave web interface. This is not necessary but it simplifies the configuration. The concept is quite simple. First of all you need a PHP script which evaluates the PATH_INFO variable and treats its value as the name of a Hyperwave object. Let's call this script 'Hyperwave'. The URL http://your.hostname/Hyperwave/name_of_object would than return the Hyperwave object with the name 'name_of_object'. Depending on the type of the object the script has to react accordingly. If it is a collection, it will probably return a list of children. If it is a document it will return the mime type and the content. A slight improvement can be achieved if the Apache rewriting engine is used. From the users point of view it would be more straight forward if the URL http://your.hostname/name_of_object would return the object. The rewriting rule is quite easy:

RewriteRule ^/(.*) /usr/local/apache/htdocs/HyperWave/$1 [L]

Now every URL relates to an object in the Hyperwave server. This causes a simple to solve problem. There is no way to execute a different script, e.g. for searching, than the 'Hyperwave' script. This can be fixed with another rewriting rule like the following:

RewriteRule ^/hw/(.*) /usr/local/apache/htdocs/hw/$1 [L]

This will reserve the directory /usr/local/apache/htdocs/hw for additional scripts and other files. Just make sure this rule is evaluated before the one above. There is just a little drawback: all Hyperwave objects whose name starts with 'hw/' will be shadowed. So, make sure you don't use such names. If you need more directories, e.g. for images just add more rules or place them all in one directory. Finally, don't forget to turn on the rewriting engine with

RewriteEngine on

My experiences have shown that you will need the following scripts:

to return the object itself
to allow searching
to identify yourself
to set your profile
one for each additional function like to show the object attributes, to show information about users, to show the status of the server, etc.

Todo

There are still some things todo:

The hw_InsertDocument has to be split into hw_insertobject() and hw_putdocument().
The names of several functions are not fixed, yet.
Most functions require the current connection as its first parameter. This leads to a lot of typing, which is quite often not necessary if there is just one open connection. A default connection will improve this.
Conversion form object record into object array needs to handle any multiple attribute.

Obsah
hw_Array2Objrec -- convert attributes from object array to object record
hw_changeobject -- Changes attributes of an object (obsolete)
hw_Children -- object ids of children
hw_ChildrenObj -- object records of children
hw_Close -- closes the Hyperwave connection
hw_Connect -- opens a connection
hw_connection_info -- Prints information about the connection to Hyperwave server
hw_Cp -- copies objects
hw_Deleteobject -- deletes object
hw_DocByAnchor -- object id object belonging to anchor
hw_DocByAnchorObj -- object record object belonging to anchor
hw_Document_Attributes -- object record of hw_document
hw_Document_BodyTag -- body tag of hw_document
hw_Document_Content -- returns content of hw_document
hw_Document_SetContent -- sets/replaces content of hw_document
hw_Document_Size -- size of hw_document
hw_dummy -- Hyperwave dummy function
hw_EditText -- retrieve text document
hw_Error -- error number
hw_ErrorMsg -- returns error message
hw_Free_Document -- frees hw_document
hw_GetAnchors -- object ids of anchors of document
hw_GetAnchorsObj -- object records of anchors of document
hw_GetAndLock -- return bject record and lock object
hw_GetChildColl -- object ids of child collections
hw_GetChildCollObj -- object records of child collections
hw_GetChildDocColl -- object ids of child documents of collection
hw_GetChildDocCollObj -- object records of child documents of collection
hw_GetObject -- object record
hw_GetObjectByQuery -- search object
hw_GetObjectByQueryColl -- search object in collection
hw_GetObjectByQueryCollObj -- search object in collection
hw_GetObjectByQueryObj -- search object
hw_GetParents -- object ids of parents
hw_GetParentsObj -- object records of parents
hw_getrellink -- Get link from source to dest relative to rootid
hw_GetRemote -- Gets a remote document
hw_GetRemoteChildren -- Gets children of remote document
hw_GetSrcByDestObj -- Returns anchors pointing at object
hw_GetText -- retrieve text document
hw_getusername -- name of currently logged in user
hw_Identify -- identifies as user
hw_InCollections -- check if object ids in collections
hw_Info -- info about connection
hw_InsColl -- insert collection
hw_InsDoc -- insert document
hw_insertanchors -- Inserts only anchors into text
hw_InsertDocument -- upload any document
hw_InsertObject -- inserts an object record
hw_mapid -- Maps global id on virtual local id
hw_Modifyobject -- modifies object record
hw_Mv -- moves objects
hw_New_Document -- create new document
hw_Objrec2Array -- convert attributes from object record to object array
hw_Output_Document -- prints hw_document
hw_pConnect -- make a persistent database connection
hw_PipeDocument -- retrieve any document
hw_Root -- root object id
hw_setlinkroot -- Set the id to which links are calculated
hw_stat -- Returns status string
hw_Unlock -- unlock object
hw_Who -- List of currently logged in users

hw_Array2Objrec

(PHP 3>= 3.0.4, PHP 4 )

hw_Array2Objrec -- convert attributes from object array to object record

Description

strin hw_array2objrec ( array object_array)

Converts an object_array into an object record. Multiple attributes like 'Title' in different languages are treated properly.

hw_changeobject

(PHP 3>= 3.0.3, PHP 4 )

hw_changeobject -- Changes attributes of an object (obsolete)

Description

void hw_changeobject ( int link, int objid, array attributes)

string hw_document_attributes ( int hw_document)

Returns the object record of the document.

For backward compatibility, hw_documentattributes() is also accepted. This is deprecated, however.

hw_Document_BodyTag

(PHP 3>= 3.0.3, PHP 4 )

hw_Document_BodyTag -- body tag of hw_document

Description

string hw_document_bodytag ( int hw_document)

int hw_document_size ( int hw_document)

Returns the size in bytes of the document.

For backward compatibility, hw_documentsize() is also accepted. This is deprecated, however.

hw_dummy

(PHP 3>= 3.0.3, PHP 4 )

hw_dummy -- Hyperwave dummy function

Description

array hw_getobject ( int connection, [int|array] objectID, string query)

Returns the object record for the object with ID objectID if the second parameter is an integer. If the second parameter is an array of integer the function will return an array of object records. In such a case the last parameter is also evaluated which is a query string.

The query string has the following syntax:

<expr> ::= "(" <expr> ")" |

"!" <expr> | /* NOT */

<expr> "||" <expr> | /* OR */

<expr> "&&" <expr> | /* AND */

<attribute> ::= /* any attribute name (Title, Author, DocumentType ...) */

<operator> ::= "=" | /* equal */

"<" | /* less than (string compare) */

array hw_getparents ( int connection, int objectID)

Returns an indexed array of object ids. Each object id belongs to a parent of the object with ID objectID.

hw_GetParentsObj

(PHP 3>= 3.0.3, PHP 4 )

hw_GetParentsObj -- object records of parents

Description

array hw_getparentsobj ( int connection, int objectID)

Returns an indexed array of object records plus an associated array with statistical information about the object records. The associated array is the last entry of the returned array. Each object record belongs to a parent of the object with ID objectID.

hw_getrellink

(PHP 3>= 3.0.3, PHP 4 )

hw_getrellink -- Get link from source to dest relative to rootid

Description

string hw_getrellink ( int link, int rootid, int sourceid, int destid)

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

hw_InsertDocument

(PHP 3>= 3.0.3, PHP 4 )

hw_InsertDocument -- upload any document

int hw_modifyobject ( int connection, int object_to_change, array remove, array add, int mode)

This command allows to remove, add, or modify individual attributes of an object record. The object is specified by the Object ID object_to_change. The first array remove is a list of attributes to remove. The second array add is a list of attributes to add. In order to modify an attribute one will have to remove the old one and add a new one. hw_modifyobject() will always remove the attributes before it adds attributes unless the value of the attribute to remove is not a string or array.

The last parameter determines if the modification is performed recursively. 1 means recurive modification. If some of the objects cannot be modified they will be skiped without notice. hw_error() may not indicate an error though some of the objects could not be modified.

The keys of both arrays are the attributes name. The value of each array element can either be an array, a string or anything else. If it is an array each attribute value is constructed by the key of each element plus a colon and the value of each element. If it is a string it is taken as the attribute value. An empty string will result in a complete removal of that attribute. If the value is neither a string nor an array but something else, e.g. an integer, no operation at all will be performed on the attribute. This is neccessary if you want to to add a completely new attribute not just a new value for an existing attribute. If the remove array contained an empty string for that attribute, the attribute would be tried to be removed which would fail since it doesn't exist. The following addition of a new value for that attribute would also fail. Setting the value for that attribute to e.g. 0 would not even try to remove it and the addition will work.

If you would like to change the attribute 'Name' with the current value 'books' into 'articles' you will have to create two arrays and call hw_modifyobject().

Příklad 1. modifying an attribute

// $connect is an existing connection to the Hyperwave server // $objid is the ID of the object to modify $remarr = array("Name" => "books"); $addarr = array("Name" => "articles"); $hw_modifyobject($connect, $objid, $remarr, $addarr);
In order to delete/add a name=value pair from/to the object record just pass the remove/add array and set the last/third parameter to an empty array. If the attribute is the first one with that name to add, set attribute value in the remove array to an integer.

Příklad 2. adding a completely new attribute

// $connect is an existing connection to the Hyperwave server // $objid is the ID of the object to modify $remarr = array("Name" => 0); $addarr = array("Name" => "articles"); $hw_modifyobject($connect, $objid, $remarr, $addarr);

Poznámka: Multilingual attributes, e.g. 'Title', can be modified in two ways. Either by providing the attributes value in its native form 'language':'title' or by providing an array with elements for each language as described above. The above example would than be:

Příklad 3. modifying Title attribute

$remarr = array("Title" => "en:Books");
       $addarr = array("Title" => "en:Articles");
       $hw_modifyobject($connect, $objid, $remarr, $addarr);

Příklad 4. modifying Title attribute

$remarr = array("Title" => array("en" => "Books"));
       $addarr = array("Title" => array("en" => "Articles", "ge"=>"Artikel"));
       $hw_modifyobject($connect, $objid, $remarr, $addarr);

This removes the english title 'Books' and adds the english title 'Articles' and the german title 'Artikel'.

Příklad 5. removing attribute

$remarr = array("Title" => "");
       $addarr = array("Title" => "en:Articles");
       $hw_modifyobject($connect, $objid, $remarr, $addarr);

Poznámka: This will remove all attributes with the name 'Title' and adds a new 'Title' attribute. This comes in handy if you want to remove attributes recursively.

Poznámka: If you need to delete all attributes with a certain name you will have to pass an empty string as the attribute value.

Poznámka: Only the attributes 'Title', 'Description' and 'Keyword' will properly handle the language prefix. If those attributes don't carry a language prefix, the prefix 'xx' will be assigned.

Poznámka: The 'Name' attribute is somewhat special. In some cases it cannot be complete removed. You will get an error message 'Change of base attribute' (not clear when this happens). Therefore you will always have to add a new Name first and than remove the old one.

Poznámka: You may not suround this function by calls to hw_getandlock() and hw_unlock(). hw_modifyobject() does this internally.

Returns TRUE if no error occurs otherwise FALSE.

hw_Mv

(PHP 3>= 3.0.3, PHP 4 )

hw_Mv -- moves objects

Description

int hw_mv ( int connection, array object id array, int source id, int destination id)

Moves the objects with object ids as specified in the second parameter from the collection with id source id to the collection with the id destination id. If the destination id is 0 the objects will be unlinked from the source collection. If this is the last instance of that object it will be deleted. If you want to delete all instances at once, use hw_deleteobject().

int hw_output_document ( int hw_document)

Prints the document without the BODY tag.

For backward compatibility, hw_outputdocument() is also accepted. This is deprecated, however.

hw_pConnect

(PHP 3>= 3.0.3, PHP 4 )

hw_pConnect -- make a persistent database connection

Description

int hw_pconnect ( string host, int port, string username, string password)

Returns a connection index on success, or FALSE if the connection could not be made. Opens a persistent connection to a Hyperwave server. Each of the arguments should be a quoted string, except for the port number. The username and password arguments are optional and can be left out. In such a case no identification with the server will be done. It is similar to identify as user anonymous. This function returns a connection index that is needed by other Hyperwave functions. You can have multiple persistent connections open at once.

hw_PipeDocument

(PHP 3>= 3.0.3, PHP 4 )

hw_PipeDocument -- retrieve any document

Description

int hw_pipedocument ( int connection, int objectID)

Returns the Hyperwave document with object ID objectID. If the document has anchors which can be inserted, they will have been inserted already. The document will be transfered via a special data connection which does not block the control connection.

See also hw_gettext() for more on link insertion, hw_free_document(), hw_document_size(), hw_document_bodytag(), and hw_output_document().

hw_Root

(PHP 3>= 3.0.3, PHP 4 )

hw_Root -- root object id

int hw_unlock ( int connection, int objectID)

Unlocks a document, so other users regain access.

hw_Who

(PHP 3>= 3.0.3, PHP 4 )

hw_Who -- List of currently logged in users

Description

int hw_who ( int connection)

Returns an array of users currently logged into the Hyperwave server. Each entry in this array is an array itself containing the elements id, name, system, onSinceDate, onSinceTime, TotalTime and self. 'self' is 1 if this entry belongs to the user who initianted the request.

XXXIX. Hyperwave API functions

Introduction

Hyperwave has been developed at IICM in Graz. It started with the name Hyper-G and changed to Hyperwave when it was commercialised (If I remember properly it was in 1996).

Hyperwave is not free software. The current version, 5.5, is available at http://www.hyperwave.com/. A time limited version can be ordered for free (30 days).

Requirements

Since 2001 there is a Hyperwave SDK available. It supports Java, JavaScript and C++. This PHP Extension is based on the C++ interface. In order to activate the hwapi support in PHP you will have to install the Hyperwave SDK first and configure PHP with --with-hwapi=<dir$gt;.

Classes

The API provided by the HW_API extension is fully object oriented. It is very similar to the C++ interface of the Hyperwave SDK. It consist of the following classes.

HW_API
HW_API_Object
HW_API_Attribute
HW_API_Error
HW_API_Content
HW_API_Reason

Some basic classes like HW_API_String, HW_API_String_Array, etc., which exist in the Hyperwave SDK have not been implemented since PHP has powerful replacements for them.

Each class has certain method, whose names are identical to its counterparts in the Hyperwave SDK. Passing arguments to this function differs from all the other PHP Extension but is close to the C++ API of the HW SDK. Instead of passing serval parameters they are all put into an associated array and passed as one paramter. The names of the keys are identical to those documented in the HW SDK. The common parameters are listed below. If other parameters are required they will be documented if needed.

objectIdentifier The name or id of an object, e.g. "rootcollection", "0x873A8768 0x00000002".
parentIdentifier The name or id of an object which is considered to be a parent.
object An instance of class HW_API_Object.
parameters An instance of class HW_API_Object.
version The version of an object.
mode An integer value determine the way an operation is executed.
attributeSelector Any array of strings, each containing a name of an attribute. This is used if you retrieve the object record and want to include certain attributes.
objectQuery A query to select certain object out of a list of objects. This is used to reduce the number of objects which was delivered by a function like hw_api->children() or hw_api->find().

Integration with Apache

The integration with Apache and possible other servers is already described in the Hyperwave Modul which has been the first extension to connect a Hyperwave Server.

Obsah
hw_api_attribute->key -- Returns key of the attribute
hw_api_attribute->langdepvalue -- Returns value for a given language
hw_api_attribute->value -- Returns value of the attribute
hw_api_attribute->values -- Returns all values of the attribute
hw_api_attribute -- Creates instance of class hw_api_attribute
hw_api->checkin -- Checks in an object
hw_api->checkout -- Checks out an object
hw_api->children -- Returns children of an object
hw_api_content->mimetype -- Returns mimetype
hw_api_content->read -- Read content
hw_api->content -- Returns content of an object
hw_api->copy -- Copies physically
hw_api->dbstat -- Returns statistics about database server
hw_api->dcstat -- Returns statistics about document cache server
hw_api->dstanchors -- Returns a list of all destination anchors
hw_api->dstofsrcanchors -- Returns destination of a source anchor
hw_api_error->count -- Returns number of reasons
hw_api_error->reason -- Returns reason of error
hw_api->find -- Search for objects
hw_api->ftstat -- Returns statistics about fulltext server
hwapi_hgcsp -- Returns object of class hw_api
hw_api->hwstat -- Returns statistics about Hyperwave server
hw_api->identify -- Log into Hyperwave Server
hw_api->info -- Returns information about server configuration
hw_api->insert -- Inserts a new object
hw_api->insertanchor -- Inserts a new object of type anchor
hw_api->insertcollection -- Inserts a new object of type collection
hw_api->insertdocument -- Inserts a new object of type document
hw_api->link -- Creates a link to an object
hw_api->lock -- Locks an object
hw_api->move -- Moves object between collections
hw_api_content -- Create new instance of class hw_api_content
hw_api_object->assign -- Clones object
hw_api_object->attreditable -- Checks whether an attribute is editable
hw_api_object->count -- Returns number of attributes
hw_api_object->insert -- Inserts new attribute
hw_api_object -- Creates a new instance of class hw_api_object
hw_api_object->remove -- Removes attribute
hw_api_object->title -- Returns the title attribute
hw_api_object->value -- Returns value of attribute
hw_api->object -- Retrieve attribute information
hw_api->objectbyanchor -- Returns the object an anchor belongs to
hw_api->parents -- Returns parents of an object
hw_api_reason->description -- Returns description of reason
hw_api_reason->type -- Returns type of reason
hw_api->remove -- Delete an object
hw_api->replace -- Replaces an object
hw_api->setcommitedversion -- Commits version other than last version
hw_api->srcanchors -- Returns a list of all source anchors
hw_api->srcsofdst -- Returns source of a destination object
hw_api->unlock -- Unlocks a locked object
hw_api->user -- Returns the own user object
hw_api->userlist -- Returns a list of all logged in users

HW_API_CHECKIN_NORMAL: Checks in and commits the object. The object must be a document.
HW_API_CHECKIN_RECURSIVE: If the object to check in is a collection, all children will be checked in recursively if they are documents. Trying to check in a collection would result in an error.
HW_API_CHECKIN_FORCE_VERSION_CONTROL: Checks in an object even if it is not under version control.
HW_API_CHECKIN_REVERT_IF_NOT_CHANGED: Check if the new version is different from the last version. Unless this is the case the object will be checked in.
HW_API_CHECKIN_KEEP_TIME_MODIFIED: Keeps the time modified from the most recent object.
HW_API_CHECKIN_NO_AUTO_COMMIT: The object is not automatically commited on checkin.

hw_api->checkout

(unknown)

hw_api->checkout -- Checks out an object

Description

object checkout ( array parameter)

This function checks out an object or a whole hiearchie of objects. The parameters array contains the required element 'objectIdentifier' and the optional element 'version', 'mode' and 'objectQuery'. 'mode' can be one of the following values:

HW_API_CHECKIN_NORMAL: Checks out an object. The object must be a document.
HW_API_CHECKIN_RECURSIVE: If the object to check out is a collection, all children will be checked out recursively if they are documents. Trying to check out a collection would result in an error.

hw_api->children

(unknown)

hw_api->children -- Returns children of an object

Description

array children ( array parameter)

object dbstat ( array parameter)

hw_api->dcstat

(unknown)

hw_api->dcstat -- Returns statistics about document cache server

object ftstat ( array parameter)

hwapi_hgcsp

(unknown)

hwapi_hgcsp -- Returns object of class hw_api

Description

object hwapi_hgcsp ( string hostname [, int port])

Opens a connection to the Hyperwave server on host hostname. The protocol used is HGCSP. If you do not pass a port number, 418 is used.

hw_api->hwstat

(unknown)

hw_api->hwstat -- Returns statistics about Hyperwave server

Description

object hwstat ( array parameter)

hw_api->identify

(unknown)

hw_api->identify -- Log into Hyperwave Server

Description

object identify ( array parameter)

Logs into the Hyperwave Server. The parameter array must contain the elements 'username' und 'password'.

The return value will be an object of type HW_API_Error if identification failed or TRUE if it was successful.

hw_api->info

(unknown)

hw_api->info -- Returns information about server configuration

Description

object info ( array parameter)

hw_api->insert

(unknown)

hw_api->insert -- Inserts a new object

Description

object insert ( array parameter)

Insert a new object. The object type can be user, group, document or anchor. Depending on the type other object attributes has to be set. The parameter array contains the required elements 'object' and 'content' (if the object is a document) and the optional parameters 'parameters', 'mode' and 'attributeSelector'. The 'object' must contain all attributes of the object. 'parameters' is an object as well holding futher attributes like the destination (attribute key is 'Parent'). 'content' is the content of the document. 'mode' can be a combination of the following flags:

HW_API_INSERT_NORMAL: The object in inserted into the server.
HW_API_INSERT_FORCE-VERSION-CONTROL
HW_API_INSERT_AUTOMATIC-CHECKOUT
HW_API_INSERT_PLAIN
HW_API_INSERT_KEEP_TIME_MODIFIED
HW_API_INSERT_DELAY_INDEXING

The function returns true on success or an error object.

hw_api->lock

(unknown)

hw_api->lock -- Locks an object

Description

object lock ( array parameter)

Locks an object for exclusive editing by the user calling this function. The object can be only unlocked by this user or the sytem user. The parameter array contains the required element 'objectIdentifier' and the optional parameters 'mode' and 'objectquery'. 'mode' determines how an object is locked. HW_API_LOCK_NORMAL means, an object is locked until it is unlocked. HW_API_LOCK_RECURSIVE is only valid for collection and locks all objects within th collection und possible subcollections. HW_API_LOCK_SESSION means, an object is locked only as long as the session is valid.

hw_api->move

(unknown)

hw_api->move -- Moves object between collections

object replace ( array parameter)

Replaces the attributes and the content of an object The parameter array contains the required elements 'objectIdentifier' and 'object' and the optional parameters 'content', 'parameters', 'mode' and 'attributeSelector'. 'objectIdentifier' contains the object to be replaced. 'object' contains the new object. 'content' contains the new content. 'parameters' contain extra information for HTML documents. HTML_Language is the letter abbreviation of the language of the title. HTML_Base sets the base attribute of the HTML document. 'mode' can be a combination of the following flags:

HW_API_REPLACE_NORMAL: The object on the server is replace with the object passed.
HW_API_REPLACE_FORCE_VERSION_CONTROL
HW_API_REPLACE_AUTOMATIC_CHECKOUT
HW_API_REPLACE_AUTOMATIC_CHECKIN
HW_API_REPLACE_PLAIN
HW_API_REPLACE_REVERT_IF_NOT_CHANGED
HW_API_REPLACE_KEEP_TIME_MODIFIED

hw_api->setcommitedversion

(unknown)

hw_api->setcommitedversion -- Commits version other than last version

Description

object setcommitedversion ( array parameter)

object unlock ( array parameter)

Unlocks a locked object. Only the user who has locked the object and the system user may unlock an object. The parameter array contains the required element 'objectIdentifier' and the optional parameters 'mode' and 'objectquery'. The meaning of 'mode' is the same as in function hwapi_lock().

Returns true on success or an object of class HW_API_Error.

hw_api->user

(unknown)

hw_api->user -- Returns the own user object

Description

object user ( array parameter)

hw_api->userlist

(unknown)

hw_api->userlist -- Returns a list of all logged in users

Description

object userlist ( array parameter)

XL. ICAP funkce

Pokud chcete používat tyto funkce, musíte PHP zkompilovat s --with-icap. To vyžaduje nainstalovanou icap knihovnu. Stáhněte si nejnovější verzi z http://icap.chek.com/, zkompilujte ji a nainstalujte.

Obsah
icap_close -- Zavřít ICAP stream
icap_create_calendar -- Create a new calendar
icap_delete_calendar -- Delete a calendar
icap_delete_event -- Delete an event from an ICAP calendar
icap_fetch_event -- Získat událost z kalendářového stream
icap_list_alarms -- Vrátit seznam událostí, které mají v dané datum/čas puštěný alarm
icap_list_events -- Vrátit seznam událostí mezi dvěma daty
icap_open -- Otevřít ICAP spojení
icap_rename_calendar -- Rename a calendar
icap_reopen -- Reopen ICAP stream to new calendar
icap_snooze -- Zapnout alarm
icap_store_event -- Uložit událost do ICAP kalendáře

icap_close

(unknown)

icap_close -- Zavřít ICAP stream

int icap_fetch_event ( int stream_id, int event_id [, int options])

icap_fetch_event() získá událost z kalendářového streamu určenou argumtem event_id.

Vrací objekt události obsahující:

int id - ID této události.
int public - TRUE, pokud je událost veřejná, FALSE, pokud je soukromá
string category - kategorie této události
string title - titul této události
string description - popis této události
int alarm - kolik minut před touto událostí se má odeslat alarm/připomínka
object start - Objekt obsahující datetime záznam.
object end - Objekt obsahující datetime záznam.

Všechny datetime záznamy tvoří objekt, který obsahuje:

int year - rok
int month - měsíc
int mday - den v měsíci
int hour - hodinu
int min - minuty
int sec - sekundy

icap_list_alarms

(PHP 4 )

icap_list_alarms -- Vrátit seznam událostí, které mají v dané datum/čas puštěný alarm

Popis

int icap_list_alarms ( int stream_id, array date, array time)

Vrací pole identifikátorů událostí, které mají v dané datum/čas puštěný alarm.

icap_list_alarms() function přijímá datum v kalendářovém streamu. Vrací pole identifikátorů událostí, které mají v dané datum/čas puštěný alarm.

Všechny datetime záznamy tvoří objekt, který obsahuje:

int year - rok
int month - měsíc
int mday - den v měsíci
int hour - hodinu
int min - minuty
int sec - sekundy

icap_list_events

(PHP 4 )

icap_list_events -- Vrátit seznam událostí mezi dvěma daty

Popis

array icap_list_events ( int stream_id, int begin_date [, int end_date])

Vrací pole id událostí, které jsou mezi dvěma danými daty.

icap_list_events() přijímá počáteční a konečné datum kalendářového streamu. Vrací pole identifikátorů událostí, které jsou mezi těmito dvěma daty.

Všechny datetime záznamy tvoří objekt, který obsahuje:

int year - rok
int month - měsíc
int mday - den v měsíci
int hour - hodinu
int min - minuty
int sec - sekundy

Všechny datetime záznamy tvoří objekt, který obsahuje:

int year - rok
int month - měsíc
int mday - den v měsíci
int hour - hodinu
int min - minuty
int sec - sekundy

Při úspěchu vrací TRUE, při chybě FALSE.

XLI. iconv functions

Úvod

This module contains an interface to the iconv library functions. The Iconv library functions convert files between various character sets encodings. The supported character sets depend on iconv() implementation on your system. Note that iconv() function in some system is not work well as you expect. In this case, you should install libiconv library.

Požadavky

You must have iconv() function in standard C library or libiconv installed on your system. libiconv library is available from http://www.gnu.org/software/libiconv/.

Instalace

To be able to use the functions defined in this module you must compile your PHP interpreter using the configure line --with-iconv.

Konfigurace běhu

Toto rozšíření nemá definováno žádné konfigurační direktivy.

Typy prostředků

Toto rezšíření nemá definován žádný typ prostředku (resource).

Předdefinované konstanty

Toto rozšíření nemá definovány žádné konstanty.

Obsah
iconv_get_encoding -- Get current setting for character encoding conversion
iconv_set_encoding -- Set current setting for character encoding conversion
iconv -- Convert string to requested character encoding
ob_iconv_handler -- Convert character encoding as output buffer handler

iconv_get_encoding

(PHP 4 >= 4.0.5)

iconv_get_encoding -- Get current setting for character encoding conversion

array ob_iconv_handler ( string contents, int status)

It converts the string encoded in internal_encoding to output_encoding.

internal_encoding and output_encoding should be defined by iconv_set_encoding() or in configuration file.

Příklad 1. ob_iconv_handler() example:

ob_start("ob_iconv_handler"); // start output buffering

XLII. Image functions

Úvod

You can use the image functions in PHP to get the size of JPEG, GIF, PNG, SWF, TIFF and JPEG2000 images.

Požadavky

If you have the GD library (available at http://www.boutell.com/gd/) you will also be able to create and manipulate images.

The format of images you are able to manipulate depend on the version of GD you install, and any other libraries GD might need to access those image formats. Versions of GD older than gd-1.6 support gif format images, and do not support png, where versions greater than gd-1.6 support png, not gif.

If you have PHP compiled with --enable-exif you are able to work with information stored in headers of JPEG and TIFF images. These functions do not require the GD library.

Instalace

In order to read and write images in jpeg format, you will need to obtain and install jpeg-6b (available at ftp://ftp.uu.net/graphics/jpeg/), and then recompile GD to make use of jpeg-6b. You will also have to compile PHP with --with-jpeg-dir=/path/to/jpeg-6b.

To add support for Type 1 fonts, you can install t1lib (available at ftp://sunsite.unc.edu/pub/Linux/libs/graphics/), and then add --with-t1lib[=dir].

Konfigurace běhu

Toto rozšíření nemá definováno žádné konfigurační direktivy.

Typy prostředků

Toto rezšíření nemá definován žádný typ prostředku (resource).

Předdefinované konstanty

Tyto konstanty jsou definovány tímto rozšířením a budou k dispozici pouze tehdy, bylo-li rozšíření zkompilováno společně s PHP nebo dynamicky zavedeno za běhu.

IMG_GIF (integer)
IMG_JPG (integer)
IMG_JPEG (integer)
IMG_PNG (integer)
IMG_WBMP (integer)
IMG_XPM (integer)
IMG_COLOR_TILED (integer)
IMG_COLOR_STYLED (integer)
IMG_COLOR_BRUSHED (integer)
IMG_COLOR_STYLEDBRUSHED (integer)
IMG_COLOR_TRANSPARENT (integer)
IMG_ARC_ROUNDED (integer)
IMG_ARC_PIE (integer)
IMG_ARC_CHORD (integer)
IMG_ARC_NOFILL (integer)
IMG_ARC_EDGED (integer)
IMAGETYPE_GIF (integer)
IMAGETYPE_JPG (integer)
IMAGETYPE_PNG (integer)
IMAGETYPE_SWF (integer)
IMAGETYPE_PSD (integer)
IMAGETYPE_BMP (integer)
IMAGETYPE_TIFF_II (integer)
IMAGETYPE_TIFF_MM (integer)
IMAGETYPE_JPC (integer)
IMAGETYPE_JP2 (integer)
IMAGETYPE_JPX (integer)
IMAGETYPE_SWC (integer)

Obsah
exif_imagetype -- Determine the type of an image
exif_read_data -- Read the EXIF headers from JPEG or TIFF
exif_thumbnail -- Retrieve the embedded thumbnail of a TIFF or JPEG image
getimagesize -- Get the size of an image
image_type_to_mime_type -- Get Mime-Type for image-type returned by getimagesize, exif_read_data, exif_thumbnail, exif_imagetype
image2wbmp -- Output image to browser or file
imagealphablending -- Set the blending mode for an image
imagearc -- Draw a partial ellipse
imagechar -- Draw a character horizontally
imagecharup -- Draw a character vertically
imagecolorallocate -- Allocate a color for an image
imagecolorat -- Get the index of the color of a pixel
imagecolorclosest -- Get the index of the closest color to the specified color
imagecolorclosestalpha -- Get the index of the closest color to the specified color + alpha
imagecolorclosesthwb -- Get the index of the color which has the hue, white and blackness nearest to the given color
imagecolordeallocate -- De-allocate a color for an image
imagecolorexact -- Get the index of the specified color
imagecolorexactalpha -- Get the index of the specified color + alpha
imagecolorresolve -- Get the index of the specified color or its closest possible alternative
imagecolorresolvealpha -- Get the index of the specified color + alpha or its closest possible alternative
imagecolorset -- Set the color for the specified palette index
imagecolorsforindex -- Get the colors for an index
imagecolorstotal -- Find out the number of colors in an image's palette
imagecolortransparent -- Define a color as transparent
imagecopy -- Copy part of an image
imagecopymerge -- Copy and merge part of an image
imagecopymergegray -- Copy and merge part of an image with gray scale
imagecopyresampled -- Copy and resize part of an image with resampling
imagecopyresized -- Copy and resize part of an image
imagecreate -- Create a new palette based image
imagecreatefromgd2 -- Create a new image from GD2 file or URL
imagecreatefromgd2part -- Create a new image from a given part of GD2 file or URL
imagecreatefromgd -- Create a new image from GD file or URL
imagecreatefromgif -- Create a new image from file or URL
imagecreatefromjpeg -- Create a new image from file or URL
imagecreatefrompng -- Create a new image from file or URL
imagecreatefromstring -- Create a new image from the image stream in the string
imagecreatefromwbmp -- Create a new image from file or URL
imagecreatefromxbm -- Create a new image from file or URL
imagecreatefromxpm -- Create a new image from file or URL
imagecreatetruecolor -- Create a new true color image
imagedashedline -- Draw a dashed line
imagedestroy -- Destroy an image
imageellipse -- Draw an ellipse
imagefill -- Flood fill
imagefilledarc -- Draw a partial ellipse and fill it
imagefilledellipse -- Draw a filled ellipse
imagefilledpolygon -- Draw a filled polygon
imagefilledrectangle -- Draw a filled rectangle
imagefilltoborder -- Flood fill to specific color
imagefontheight -- Get font height
imagefontwidth -- Get font width
imageftbbox -- Give the bounding box of a text using fonts via freetype2
imagefttext -- Write text to the image using fonts using FreeType 2
imagegammacorrect -- Apply a gamma correction to a GD image
imagegd2 -- Output GD2 image to browser or file
imagegd -- Output GD image to browser or file
imagegif -- Output image to browser or file
imageinterlace -- Enable or disable interlace
imagejpeg -- Output image to browser or file
imageline -- Draw a line
imageloadfont -- Load a new font
imagepalettecopy -- Copy the palette from one image to another
imagepng -- Output a PNG image to either the browser or a file
imagepolygon -- Draw a polygon
imagepsbbox -- Give the bounding box of a text rectangle using PostScript Type1 fonts
imagepscopyfont -- Make a copy of an already loaded font for further modification
imagepsencodefont -- Change the character encoding vector of a font
imagepsextendfont -- Extend or condense a font
imagepsfreefont -- Free memory used by a PostScript Type 1 font
imagepsloadfont -- Load a PostScript Type 1 font from file
imagepsslantfont -- Slant a font
imagepstext -- To draw a text string over an image using PostScript Type1 fonts
imagerectangle -- Draw a rectangle
imagesetbrush -- Set the brush image for line drawing
imagesetpixel -- Set a single pixel
imagesetstyle -- Set the style for line drawing
imagesetthickness -- Set the thickness for line drawing
imagesettile -- Set the tile image for filling
imagestring -- Draw a string horizontally
imagestringup -- Draw a string vertically
imagesx -- Get image width
imagesy -- Get image height
imagetruecolortopalette -- Convert a true color image to a palette image
imagettfbbox -- Give the bounding box of a text using TrueType fonts
imagettftext -- Write text to the image using TrueType fonts
imagetypes -- Return the image types supported by this PHP build
imagewbmp -- Output image to browser or file
iptcembed -- Embed binary IPTC data into a JPEG image
iptcparse -- Parse a binary IPTC http://www.iptc.org/ block into single tags.
jpeg2wbmp -- Convert JPEG image file to WBMP image file
png2wbmp -- Convert PNG image file to WBMP image file
read_exif_data -- Reads header information stored in TIFF and JPEG images

exif_imagetype

(PHP 4 CVS only)

exif_imagetype -- Determine the type of an image

Description

int|false exif_imagetype ( string filename)

exif_imagetype() reads the first bytes of an image and checks its signature. When a correct signature is found a constant will be returned otherwise the return value is FALSE. The return value is the same value that getimagesize() returns in index 2 but this function is much faster.

The following constants are defined: 1 = IMAGETYPE_GIF, 2 = IMAGETYPE_JPG, 3 = IMAGETYPE_PNG, 4 = IMAGETYPE_SWF, 5 = IMAGETYPE_PSD, 6 = IMAGETYPE_BMP, 7 = IMAGETYPE_TIFF_II (intel byte order), 8 = IMAGETYPE_TIFF_MM (motorola byte order), 9 = IMAGETYPE_JPC, 10 = IMAGETYPE_JP2, 11 = IMAGETYPE_JPX, 12 = IMAGETYPE_SWC.

This function can be used to avoid calls to other exif functions with unsupported file teypes or in conjunction with $_SERVER['HTTP_ACCEPT'] to check whether or not the viewer is able to see a specific image in his browser.

Poznámka: This function is only available in PHP 4 compiled using --enable-exif.

This function does not require the GD image library.

See also getimagesize().

exif_read_data

(PHP 4 >= 4.2.0)

exif_read_data -- Read the EXIF headers from JPEG or TIFF

Description

array exif_read_data ( string filename [, string sections [, bool arrays [, bool thumbnail]]])

The exif_read_data() function reads the EXIF headers from a JPEG or TIFF image file. It returns an associative array where the indexes are the header names and the values are the values associated with those headers. If no data can be returned the result is FALSE.

filename is the name of the file to read. This cannot be a url.

sections a comma separated list of sections that need to be present in file to produce a result array.

FILE	FileName, FileSize, FileDateTime, SectionsFound
COMPUTED	html, Width, Height, IsColor and some more if available.
ANY_TAG	Any information that has a Tag e.g. IFD0, EXIF, ...
IFD0	All tagged data of IFD0. In normal imagefiles this contains image size and so forth.
THUMBNAIL	A file is supposed to contain a thumbnail if it has a second IFD. All tagged information about the embedded thumbnail is stored in this section.
COMMENT	Comment headers of JPEG images.
EXIF	The EXIF section is a sub section of IFD0. It contains more detailed information about an image. Most of these entries are digital camera related.

arrays specifies whether or not each section becomes an array. The sections FILE, COMPUTED and THUMBNAIL allways become arrays as they may contain values whose names are conflict with other sections.

thumbnail whether or not to read the thumbnail itself and not only its tagged data.

Poznámka: Exif headers tend to be present in JPEG/TIFF images generated by digital cameras, but unfortunately each digital camera maker has a different idea of how to actually tag their images, so you can't always rely on a specific Exif header being present.

Příklad 1. exif_read_data() example

<?php echo "test1.jpg:<br />\n"; $exif = exif_read_data ('tests/test1.jpg','IFD0'); echo $exif===false ? "No header data found.<br />\n" : "Image contains headers<br />"; $exif = exif_read_data ('tests/test2.jpg',0,true); echo "test2.jpg:<br />\n"; foreach($exif as $key=>$section) { foreach($section as $name=>$val) { echo "$key.$name: $val<br />\n"; } }?>

The first call fails because the image has no header information.

test1.jpg: No header data found. test2.jpg: FILE.FileName: test2.jpg FILE.FileDateTime: 1017666176 FILE.FileSize: 1240 FILE.FileType: 2 FILE.SectionsFound: ANY_TAG, IFD0, THUMBNAIL, COMMENT COMPUTED.html: width="1" height="1" COMPUTED.Height: 1 COMPUTED.Width: 1 COMPUTED.IsColor: 1 COMPUTED.ByteOrderMotorola: 1 COMPUTED.UserComment: Exif test image. COMPUTED.UserCommentEncoding: ASCII COMPUTED.Copyright: Photo (c) M.Boerger, Edited by M.Boerger. COMPUTED.Copyright.Photographer: Photo (c) M.Boerger COMPUTED.Copyright.Editor: Edited by M.Boerger. IFD0.Copyright: Photo (c) M.Boerger IFD0.UserComment: ASCII THUMBNAIL.JPEGInterchangeFormat: 134 THUMBNAIL.JPEGInterchangeFormatLength: 523 COMMENT.0: Comment #1. COMMENT.1: Comment #2. COMMENT.2: Comment #3end

Poznámka: If the image contains any IFD0 data then COMPUTED contains the entry ByteOrderMotorola which is 0 for little-endian (intel) and 1 for big-endian (motorola) byte order. This was added in PHP 4.3.

When an Exif header contains a Copyright note this itself can contain two values. As the solution is inconsitent in the Exif 2.10 standard the COMPUTED section will return both entries Copyright.Photographer and Copyright.Editor while the IFD0 sections contains the byte array with the NULL character that splits both entries. Or just the first entry if the datatype was wrong (normal behaviour of Exif). The COMPUTED will contain also an entry Copyright Which is either the original copyright string or it is a comma separated list of photo and editor copyright.

Poznámka: The tag UserComment has the same problem as the Copyright tag. It can store two values first the encoding used and second the value itself. If so the IFD section only contains the encoding or a byte array. The COMPUTED section will store both in the entries UserCommentEncoding and UserComment. The entry UserComment is available in both cases so it should be used in preference to the value in IFD0 section.

If the user comment uses Unicode or JIS encoding and the module mbstring is available this encoding will automatically changed according to the exif ini settings. This was added in PHP 4.3.

Poznámka: Height and Width are computed the same way getimagesize() does so their values must not be part of any header returned. Also html is a height/width text string to be used inside normal HTML.

Poznámka: Starting from PHP 4.3 the function can read all embedded IFD data including arrays (returned as such). Also the size of an embedded thumbnail is returned in THUMBNAIL subarray and the function exif_read_data() can return thumbnails in TIFF format. Last but not least there is no longer a maximum legth for returned values (not until memory limit is reached).

Poznámka: This function is only available in PHP 4 compiled using --enable-exif. Its functionality and behaviour has changed in PHP 4.2. Earlier versions are very unstable.

Since PHP 4.3 user comment can automatically change encoding if PHP 4 was compiled using --enable-mbstring.

This function does not require the GD image library.

See also exif_thumbnail() and getimagesize().

exif_thumbnail

(PHP 4 >= 4.2.0)

exif_thumbnail -- Retrieve the embedded thumbnail of a TIFF or JPEG image

Description

string exif_thumbnail ( string filename [, int &width [, int &height]])

exif_thumbnail() reads the embedded thumbnail of a TIFF or JPEG image. If the image contains no thumbnail FALSE will be returned.

Both parameters width and height are available since PHP 4.3 and return the size of the thumbnail. It is possible that exif_thumbnail() cannot create an image but determine its size. In this case the return value is FALSE but width and height are set.

Starting from version PHP 4.3 the function exif_thumbnail() can return thumbnails in TIFF format.

Poznámka: This function is only available in PHP 4 compiled using --enable-exif. Its functionality and behaviour has changed in PHP 4.2

This function does not require the GD image library.

See also exif_read_data().

getimagesize

(PHP 3, PHP 4 )

getimagesize -- Get the size of an image

Description

array getimagesize ( string filename [, array imageinfo])

The getimagesize() function will determine the size of any GIF, JPG, PNG, SWF, SWC, PSD, TIFF, BMP or IFF image file and return the dimensions along with the file type and a height/width text string to be used inside a normal HTML IMG tag.

Returns an array with 4 elements. Index 0 contains the width of the image in pixels. Index 1 contains the height. Index 2 a flag indicating the type of the image. 1 = GIF, 2 = JPG, 3 = PNG, 4 = SWF, 5 = PSD, 6 = BMP, 7 = TIFF(intel byte order), 8 = TIFF(motorola byte order, 9 = JPC, 10 = JP2, 11 = JPX, 12 = JB2, 13 = SWC, 14 = IFF. These values correspond to the IMAGETYPE constants that were added in PHP 4.3. Index 3 is a text string with the correct height="yyy" width="xxx" string that can be used directly in an IMG tag.

Příklad 1. getimagesize (file)

<?php $size = getimagesize ("img/flag.jpg"); echo "<img src=\"img/flag.jpg\" {$size[3]}>"; ?>

Příklad 2. getimagesize (URL)

<?php $size = getimagesize ("http://www.example.com/gifs/logo.gif"); ?>

With JPG images, two extras index are returned : channels and bits. channels will be 3 for RGB pictures, and 4 for CMYK pictures. bits is the number of bits for each color.

Since PHP 4.3 bits and channels are present for other image types, too. But these values or there presence can be a bit confusing. As example GIF allways uses 3 channels per pixel but the number of bits per pixel cannot be computed for an animated GIF with a global colortable.

Some formats may contain no image or multiple images. In such cases GetImageSize might not be able to determine the size and returns zero for width and height.

Since PHP 4.3 GetImageSize() does also return the additional mime that receives the mime-type of the image. This information can be used to deliver images with correct http Content-type header if this is unknown:

Příklad 3. getimagesize and mime-type

<?php $size = getimagesize ($filename); $fp=fopen($filename, "rb"); if ($size && $fp) { header("Content-type: {$size['mime']}"); fpassthru($fp); exit; } else // error ?>

If accessing the filename image is impossible, or if it isn't a valid picture, getimagesize() will return NULL and generate a warning.

The optional imageinfo parameter allows you to extract some extended information from the image file. Currently this will return the different JPG APP markers in an associative Array. Some Programs use these APP markers to embed text information in images. A very common one is to embed IPTC http://www.iptc.org/ information in the APP13 marker. You can use the iptcparse() function to parse the binary APP13 marker into something readable.

Příklad 4. getimagesize returning IPTC

<?php $size = getimagesize ("testimg.jpg",&$info); if (isset ($info["APP13"])) { $iptc = iptcparse ($info["APP13"]); var_dump ($iptc); } ?>

Poznámka: TIFF support was added in PHP 4.2. JPEG2000 support will be added in PHP 4.3.

This function does not require the GD image library.

See also image_type_to_mime_type(), exif_imagetype(), exif_read_data() and exif_thumbnail().

URL support was added in PHP 4.0.5

image_type_to_mime_type

(unknown)

image_type_to_mime_type -- Get Mime-Type for image-type returned by getimagesize, exif_read_data, exif_thumbnail, exif_imagetype

Description

string image_type_to_mime_type ( int imagetype)

The image_type_to_mime_type() function will determine the Mime-Type for an IMAGETYPE constant.

Příklad 1. image_type_to_mime_type (file)

<?php header ("Content-type: ".image_type_to_mime_type (IMAGETYPE_PNG)); ?>

Poznámka: This function does not require the GD image library.

See also getimagesize(), exif_imagetype(), exif_read_data() and exif_thumbnail().

image2wbmp

(PHP 4 >= 4.0.5)

image2wbmp -- Output image to browser or file

Description

int image2wbmp ( resource image [, string filename [, int threshold]])

image2wbmp() creates the WBMP file in filename from the image image. The image argument is the return from imagecreate().

The filename argument is optional, and if left off, the raw image stream will be output directly. By sending an image/vnd.wap.wbmp content-type using header(), you can create a PHP script that outputs WBMP images directly.

Poznámka: WBMP support is only available if PHP was compiled against GD-1.8 or later.

imagealphablending

(PHP 4 >= 4.0.6)

imagealphablending -- Set the blending mode for an image

Description

int imagealphablending ( resource image, bool blendmode)

imagealphablending() allows for two different modes of drawing on truecolor images. In blending mode, the alpha channel component of the color supplied to all drawing function, such as imagesetpixel() determines how much of the underlying color should be allowed to shine through. As a result, gd automatically blends the existing color at that point with the drawing color, and stores the result in the image. The resulting pixel is opaque. In non-blending mode, the drawing color is copied literally with its alpha channel information, replacing the destination pixel. Blending mode is not available when drawing on palette images. If blendmode is TRUE, then blending mode is enabled, otherwise disabled.

Poznámka: This function was added in PHP 4.0.6 and requires GD 2.0.1

imagearc

(PHP 3, PHP 4 )

imagearc -- Draw a partial ellipse

int imagecolorallocate ( resource image, int red, int green, int blue)

imagecolorallocate() returns a color identifier representing the color composed of the given RGB components. The im argument is the return from the imagecreate() function. red, green and blue are the values of the red, green and blue component of the requested color respectively. These parameters are integers between 0 and 255. imagecolorallocate() must be called to create each color that is to be used in the image represented by image.

$white = imagecolorallocate ($im, 255, 255, 255);
$black = imagecolorallocate ($im, 0, 0, 0);

Returns -1 if the allocation failed.

imagecolorat

(PHP 3, PHP 4 )

imagecolorat -- Get the index of the color of a pixel

Description

int imagecolorat ( resource image, int x, int y)

Returns the index of the color of the pixel at the specified location in the image specified by image.

imagecolorclosest

(PHP 3, PHP 4 )

imagecolorclosest -- Get the index of the closest color to the specified color

Description

int imagecolorclosest ( resource image, int red, int green, int blue)

Returns the index of the color in the palette of the image which is "closest" to the specified RGB value.

The "distance" between the desired color and each color in the palette is calculated as if the RGB values represented points in three-dimensional space.

imagecolorclosestalpha

(PHP 4 >= 4.0.6)

imagecolorclosestalpha -- Get the index of the closest color to the specified color + alpha

Description

int imagecolortransparent ( resource image [, int color])

imagecolortransparent() sets the transparent color in the image image to color. image is the image identifier returned by imagecreate() and color is a color identifier returned by imagecolorallocate().

Poznámka: The transparent color is a property of the image, transparency is not a property of the color. Once you have a set a color to be the transparent color, any regions of the image in that color that were drawn previously will be transparent.

The identifier of the new (or current, if none is specified) transparent color is returned.

imagecopy

(PHP 3>= 3.0.6, PHP 4 )

imagecopy -- Copy part of an image

Description

int imagecopy ( resource dst_im, resource src_im, int dst_x, int dst_y, int src_x, int src_y, int src_w, int src_h)

imagecopymerge

(PHP 4 >= 4.0.1)

imagecopymerge -- Copy and merge part of an image

Description

int imagecopymerge ( resource dst_im, resource src_im, int dst_x, int dst_y, int src_x, int src_y, int src_w, int src_h, int pct)

Copy a part of src_im onto dst_im starting at the x,y coordinates src_x, src_y with a width of src_w and a height of src_h. The portion defined will be copied onto the x,y coordinates, dst_x and dst_y. The two images will be merged according to pct which can range from 0 to 100. When pct = 0, no action is taken, when 100 this function behaves identically to imagecopy().

Poznámka: This function was added in PHP 4.0.6

imagecopymergegray

(PHP 4 >= 4.0.6)

imagecopymergegray -- Copy and merge part of an image with gray scale

Description

int imagecopymergegray ( resource dst_im, resource src_im, int dst_x, int dst_y, int src_x, int src_y, int src_w, int src_h, int pct)

imagecopymergegray() copy a part of src_im onto dst_im starting at the x,y coordinates src_x, src_y with a width of src_w and a height of src_h. The portion defined will be copied onto the x,y coordinates, dst_x and dst_y. The two images will be merged according to pct which can range from 0 to 100. When pct = 0, no action is taken, when 100 this function behaves identically to imagecopy().

This function is identical to imagecopymerge() except that when merging it preservese the hue of the source by converting the destination pixels to gray scale before the copy operation.

Poznámka: This function was added in PHP 4.0.6

imagecreatefromgif() returns an empty string on failure. It also outputs an error message, which unfortunately displays as a broken link in a browser. To ease debugging the following example will produce an error GIF:

Příklad 1. Example to handle an error during creation (courtesy vic@zymsys.com)

function LoadGif ($imgname) { $im = @imagecreatefromgif ($imgname); /* Attempt to open */ if (!$im) { /* See if it failed */ $im = imagecreate (150, 30); /* Create a blank image */ $bgc = imagecolorallocate ($im, 255, 255, 255); $tc = imagecolorallocate ($im, 0, 0, 0); imagefilledrectangle ($im, 0, 0, 150, 30, $bgc); /* Output an errmsg */ imagestring ($im, 1, 5, 5, "Error loading $imgname", $tc); } return $im; }

Poznámka: Since all GIF support was removed from the GD library in version 1.6, this function is not available if you are using that version of the GD library.

(PHP 4 >= 4.0.1)

imagecreatefromwbmp -- Create a new image from file or URL

Description

resource imagecreatefromwbmp ( string filename)

imagecreatefromwbmp() returns an image identifier representing the image obtained from the given filename.

imagecreatefromwbmp() returns an empty string on failure. It also outputs an error message, which unfortunately displays as a broken link in a browser. To ease debugging the following example will produce an error WBMP:

Příklad 1. Example to handle an error during creation (courtesy vic@zymsys.com)

function LoadWBMP ($imgname) { $im = @imagecreatefromwbmp ($imgname); /* Attempt to open */ if (!$im) { /* See if it failed */ $im = imagecreate (20, 20); /* Create a blank image */ $bgc = imagecolorallocate ($im, 255, 255, 255); $tc = imagecolorallocate ($im, 0, 0, 0); imagefilledrectangle ($im, 0, 0, 10, 10, $bgc); /* Output an errmsg */ imagestring ($im, 1, 5, 5, "Error loading $imgname", $tc); } return $im; }

Poznámka: WBMP support is only available if PHP was compiled against GD-1.8 or later.

Poznámka: This function was added in PHP 4.0.6 and requires GD 2.0.1 or later

Poznámka: This function was added in PHP 4.0.6 and requires GD 2.0.2 or later

imagefill

int imagefilledellipse ( resource image, int cx, int cy, int w, int h, int col)

imagefilledellipse() draws an ellipse centered at cx, cy (top left is 0, 0) in the image represented by image. W and h specifies the ellipse's width and height respectively. The ellipse is filled using color

Poznámka: This function was added in PHP 4.0.6 and requires GD 2.0.1 or later

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

imagefttext

(PHP 4 >= 4.1.0)

imagefttext -- Write text to the image using fonts using FreeType 2

Description

array imagefttext ( resource image, int size, int angle, int x, int y, int col, string font_file, string text [, array extrainfo])

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

imagegammacorrect

(PHP 3>= 3.0.13, PHP 4 )

imagegammacorrect -- Apply a gamma correction to a GD image

int imagegif ( resource image [, string filename])

imagegif() creates the GIF file in filename from the image image. The image argument is the return from the imagecreate() function.

The image format will be GIF87a unless the image has been made transparent with imagecolortransparent(), in which case the image format will be GIF89a.

The filename argument is optional, and if left off, the raw image stream will be output directly. By sending an image/gif content-type using header(), you can create a PHP script that outputs GIF images directly.

Poznámka: Since all GIF support was removed from the GD library in version 1.6, this function is not available if you are using that version of the GD library.

The following code snippet allows you to write more portable PHP applications by auto-detecting the type of GD support which is available. Replace the sequence header ("Content-type: image/gif"); imagegif ($im); by the more flexible sequence:
<?php
if (function_exists("imagegif")) {
    header ("Content-type: image/gif");
    imagegif ($im);
}
elseif (function_exists("imagejpeg")) {
    header ("Content-type: image/jpeg");
    imagejpeg ($im, "", 0.5);
}
elseif (function_exists("imagepng")) {
    header ("Content-type: image/png");
    imagepng ($im);
}
elseif (function_exists("imagewbmp")) {
    header ("Content-type: image/vnd.wap.wbmp");
    imagewbmp ($im);
}
else
    die("No image support in this PHP server");
?>

Poznámka: As of version 3.0.18 and 4.0.2 you can use the function imagetypes() in place of function_exists() for checking the presence of the various supported image formats:
if (imagetypes() & IMG_GIF) {
    header ("Content-type: image/gif");
    imagegif ($im);
}
elseif (imagetypes() & IMG_JPG) {
        ... etc.

imageinterlace

(PHP 3, PHP 4 )

imageinterlace -- Enable or disable interlace

Description

int imageinterlace ( resource image [, int interlace])

imageinterlace() turns the interlace bit on or off. If interlace is 1 the image will be interlaced, and if interlace is 0 the interlace bit is turned off.

If the interlace bit is set and the image is used as a JPEG image, the image is created as a progressive JPEG.

This function returns whether the interlace bit is set for the image.

imagejpeg

(PHP 3>= 3.0.16, PHP 4 )

imagejpeg -- Output image to browser or file

Description

int imagejpeg ( resource image [, string filename [, int quality]])

imagejpeg() creates the JPEG file in filename from the image image. The image argument is the return from the imagecreate() function.

The filename argument is optional, and if left off, the raw image stream will be output directly. To skip the filename argument in order to provide a quality argument just use an empty string (''). By sending an image/jpeg content-type using header(), you can create a PHP script that outputs JPEG images directly.

Poznámka: JPEG support is only available if PHP was compiled against GD-1.8 or later.

quality is optional, and ranges from 0 (worst quality, smaller file) to 100 (best quality, biggest file). The default is the default IJG quality value (about 75).

If you want to output Progressive JPEGs, you need to set interlacing on with imageinterlace().

imageline

int imagepng ( resource image [, string filename])

The imagepng() outputs a GD image stream (image) in PNG format to standard output (usually the browser) or, if a filename is given by the filename it outputs the image to the file.

<?php
$im = imagecreatefrompng ("test.png");
imagepng ($im);
?>

imagepolygon

(PHP 3, PHP 4 )

imagepolygon -- Draw a polygon

Description

int imagepolygon ( resource image, array points, int num_points, int col)

imagepolygon() creates a polygon in image id. points is a PHP array containing the polygon's vertices, ie. points[0] = x0, points[1] = y0, points[2] = x1, points[3] = y1, etc. num_points is the total number of vertices.

imagepsbbox

(PHP 3>= 3.0.9, PHP 4 )

imagepsbbox -- Give the bounding box of a text rectangle using PostScript Type1 fonts

Description

array imagepsbbox ( string text, int font, int size [, int space [, int tightness [, float angle]]])

Size is expressed in pixels.

Space allows you to change the default value of a space in a font. This amount is added to the normal value and can also be negative.

Tightness allows you to control the amount of white space between characters. This amount is added to the normal character width and can also be negative.

Angle is in degrees.

Parameters space and tightness are expressed in character space units, where 1 unit is 1/1000th of an em-square.

Parameters space, tightness, and angle are optional.

The bounding box is calculated using information available from character metrics, and unfortunately tends to differ slightly from the results achieved by actually rasterizing the text. If the angle is 0 degrees, you can expect the text to need 1 pixel more to every direction.

This function returns an array containing the following elements:

0	lower left x-coordinate
1	lower left y-coordinate
2	upper right x-coordinate
3	upper right y-coordinate

imagepscopyfont

(PHP 3>= 3.0.9, PHP 4 )

imagepscopyfont -- Make a copy of an already loaded font for further modification

Description

int imagepscopyfont ( int fontindex)

Use this function if you need make further modifications to the font, for example extending/condensing, slanting it or changing it's character encoding vector, but need to keep the original along as well. Note that the font you want to copy must be one obtained using imagepsloadfont(), not a font that is itself a copied one. You can although make modifications to it before copying.

If you use this function, you must free the fonts obtained this way yourself and in reverse order. Otherwise your script will hang.

In the case everything went right, a valid font index will be returned and can be used for further purposes. Otherwise the function returns FALSE and prints a message describing what went wrong.

imagepsencodefont

(PHP 3>= 3.0.9, PHP 4 )

imagepsencodefont -- Change the character encoding vector of a font

Description

int imagepsencodefont ( int font_index, string encodingfile)

Loads a character encoding vector from from a file and changes the fonts encoding vector to it. As a PostScript fonts default vector lacks most of the character positions above 127, you'll definitely want to change this if you use an other language than english. The exact format of this file is described in T1libs documentation. T1lib comes with two ready-to-use files, IsoLatin1.enc and IsoLatin2.enc.

If you find yourself using this function all the time, a much better way to define the encoding is to set ps.default_encoding in the configuration file to point to the right encoding file and all fonts you load will automatically have the right encoding.

imagepsextendfont

(PHP 3>= 3.0.9, PHP 4 )

imagepsextendfont -- Extend or condense a font

Description

bool imagepsextendfont ( int font_index, float extend)

Extend or condense a font (font_index), if the value of the extend parameter is less than one you will be condensing the font.

imagepsfreefont

(PHP 3>= 3.0.9, PHP 4 )

imagepsfreefont -- Free memory used by a PostScript Type 1 font

Description

void imagepsfreefont ( int fontindex)

imagepsloadfont

(PHP 3>= 3.0.9, PHP 4 )

imagepsloadfont -- Load a PostScript Type 1 font from file

Description

int imagepsloadfont ( string filename)

In the case everything went right, a valid font index will be returned and can be used for further purposes. Otherwise the function returns FALSE and prints a message describing what went wrong, which you cannot read directly, while the output type is image.

<?php header ("Content-type: image/jpeg"); $im = imagecreate (350, 45); $black = imagecolorallocate ($im, 0, 0, 0); $white = imagecolorallocate ($im, 255, 255, 255); $font = imagepsloadfont ("bchbi.pfb"); // or locate your .pfb files on your machine imagepstext ($im, "Testing... It worked!", $font, 32, $white, $black, 32, 32); imagepsfreefont ($font); imagejpeg ($im, "", 100); //for best quality...your mileage may vary imagedestroy ($im); ?>

imagepsslantfont

(PHP 3>= 3.0.9, PHP 4 )

imagepsslantfont -- Slant a font

Description

bool imagepsslantfont ( int font_index, float slant)

Slant a font given by the font_index parameter with a slant of the value of the slant parameter.

imagepstext

(PHP 3>= 3.0.9, PHP 4 )

imagepstext -- To draw a text string over an image using PostScript Type1 fonts

Description

array imagepstext ( resource image, string text, int font, int size, int foreground, int background, int x, int y [, int space [, int tightness [, float angle [, int antialias_steps]]]])

Size is expressed in pixels.

Foreground is the color in which the text will be painted. Background is the color to which the text will try to fade in with antialiasing. No pixels with the color background are actually painted, so the background image does not need to be of solid color.

The coordinates given by x, y will define the origin (or reference point) of the first character (roughly the lower-left corner of the character). This is different from the imagestring(), where x, y define the upper-right corner of the first character. Refer to PostScipt documentation about fonts and their measuring system if you have trouble understanding how this works.

Space allows you to change the default value of a space in a font. This amount is added to the normal value and can also be negative.

Tightness allows you to control the amount of white space between characters. This amount is added to the normal character width and can also be negative.

Angle is in degrees.

Antialias_steps allows you to control the number of colours used for antialiasing text. Allowed values are 4 and 16. The higher value is recommended for text sizes lower than 20, where the effect in text quality is quite visible. With bigger sizes, use 4. It's less computationally intensive.

Parameters space and tightness are expressed in character space units, where 1 unit is 1/1000th of an em-square.

Parameters space, tightness, angle and antialias are optional.

This function returns an array containing the following elements:

0	lower left x-coordinate
1	lower left y-coordinate
2	upper right x-coordinate
3	upper right y-coordinate

imagerectangle

(PHP 3, PHP 4 )

imagerectangle -- Draw a rectangle

Description

int imagerectangle ( resource image, int x1, int y1, int x2, int y2, int col)

imagerectangle() creates a rectangle of color col in image image starting at upper left coordinate x1, y1 and ending at bottom right coordinate x2, y2. 0, 0 is the top left corner of the image.

imagesetbrush

(PHP 4 >= 4.0.6)

imagesetbrush -- Set the brush image for line drawing

Description

int imagesetbrush ( resource image, resource brush)

imagesetbrush() sets the brush image to be used by all line drawing functions (such as imageline() and imagepolygon()) when drawing with the special colors IMG_COLOR_BRUSHED or IMG_COLOR_STYLEDBRUSHED.

Poznámka: You need not take special action when you are finished with a brush, but if you destroy the brush image, you must not use the IMG_COLOR_BRUSHED or IMG_COLOR_STYLEDBRUSHED colors until you have set a new brush image!

Poznámka: This function was added in PHP 4.0.6

imagesetpixel

(PHP 3, PHP 4 )

imagesetpixel -- Set a single pixel

Description

int imagesetpixel ( resource image, int x, int y, int col)

imagesetpixel() draws a pixel at x, y (top left is 0, 0) in image image of color col.

imagesetstyle

(PHP 4 >= 4.0.6)

imagesetstyle -- Set the style for line drawing

Description

int imagesetstyle ( resource image, array style)

imagesetstyle() sets the style to be used by all line drawing functions (such as imageline() and imagepolygon()) when drawing with the special color IMG_COLOR_STYLED or lines of images with color IMG_COLOR_STYLEDBRUSHED.

The style parameter is an array of pixels. Following example script draws a dashed line from upper left to lower right corner of the canvas:

Příklad 1. imagesetstyle

<?php header ("Content-type: image/png"); $im = imagecreate (100, 100); $w = imagecolorallocate ($im, 255, 255, 255); $red = imagecolorallocate ($im, 255, 0, 0); /* Draw a dashed line, 5 red pixels, 5 white pixels */ $style = array ($red,$red,$red,$red,$red,$w,$w,$w,$w,$w); imagesetstyle ($im, $style); imageline ($im, 0, 0, 100, 100, IMG_COLOR_STYLED); /* Draw a line of happy faces using imagesetbrush() with imagesetstyle */ $style = array ($w,$w,$w,$w,$w,$w,$w,$w,$w,$w,$w,$w,$red); imagesetstyle ($im, $style); $brush = imagecreatefrompng ("http://www.libpng.org/pub/png/images/smile.happy.png"); imagecolortransparent ($brush, $w); imagesetbrush ($im, $brush); imageline ($im, 100, 0, 0, 100, IMG_COLOR_STYLEDBRUSHED); imagepng ($im); imagedestroy ($im); ?>

Poznámka: This function was added in PHP 4.0.6

imagesetthickness

(PHP 4 >= 4.0.6)

imagesetthickness -- Set the thickness for line drawing

Description

void imagesetthickness ( resource image, int thickness)

imagesetthickness() sets the thickness of the lines drawn when drawing rectangles, polygons, ellipses etc. etc. to thickness pixels.

Poznámka: This function was added in PHP 4.0.6 and requires GD 2.0.1 or later

imagesettile

(PHP 4 >= 4.0.6)

imagesettile -- Set the tile image for filling

Description

int imagesettile ( resource image, resource tile)

imagesettile() sets the tile image to be used by all region filling functions (such as imagefill() and imagefilledpolygon()) when filling with the special color IMG_COLOR_TILED.

A tile is an image used to fill an area with a repeated pattern. Any GD image can be used as a tile, and by setting the transparent color index of the tile image with imagecolortransparent(), a tile allows certain parts of the underlying area to shine through can be created.

Poznámka: You need not take special action when you are finished with a tile, but if you destroy the tile image, you must not use the IMG_COLOR_TILED color until you have set a new tile image!

Poznámka: This function was added in PHP 4.0.6

ncolors sets the maximum number of colors that should be retained in the palette.

Poznámka: This function was added in PHP 4.0.6 and requires GD 2.0.1 or later

imagettfbbox

(PHP 3>= 3.0.1, PHP 4 )

imagettfbbox -- Give the bounding box of a text using TrueType fonts

Description

array imagettfbbox ( int size, int angle, string fontfile, string text)

This function calculates and returns the bounding box in pixels for a TrueType text.

text: The string to be measured.
size: The font size in pixels.
fontfile: The name of the TrueType font file. (Can also be an URL.) Depending on which version of the GD library that PHP is using, it may attempt to search for files that do not begin with a leading '/' by appending '.ttf' to the filename and searching along a library-defined font path.
angle: Angle in degrees in which text will be measured.

imagettfbbox() returns an array with 8 elements representing four points making the bounding box of the text:

0	lower left corner, X position
1	lower left corner, Y position
2	lower right corner, X position
3	lower right corner, Y position
4	upper right corner, X position
5	upper right corner, Y position
6	upper left corner, X position
7	upper left corner, Y position

The points are relative to the text regardless of the angle, so "upper left" means in the top left-hand corner seeing the text horizontallty.

This function requires both the GD library and the FreeType library.

imagettftext

(PHP 3, PHP 4 )

imagettftext -- Write text to the image using TrueType fonts

Description

array imagettftext ( resource image, int size, int angle, int x, int y, int col, string fontfile, string text)

imagettftext() draws the string text in the image identified by image, starting at coordinates x, y (top left is 0, 0), at an angle of angle in color col, using the TrueType font file identified by fontfile. Depending on which version of the GD library that PHP is using, when fontfile does not begin with a leading '/', '.ttf' will be appended to the filename and the the library will attempt to search for that filename along a library-defined font path.

The coordinates given by x, y will define the basepoint of the first character (roughly the lower-left corner of the character). This is different from the imagestring(), where x, y define the upper-right corner of the first character.

Angle is in degrees, with 0 degrees being left-to-right reading text (3 o'clock direction), and higher values representing a counter-clockwise rotation. (i.e., a value of 90 would result in bottom-to-top reading text).

Fontfile is the path to the TrueType font you wish to use.

Text is the text string which may include UTF-8 character sequences (of the form: {) to access characters in a font beyond the first 255.

Col is the color index. Using the negative of a color index has the effect of turning off antialiasing.

imagettftext() returns an array with 8 elements representing four points making the bounding box of the text. The order of the points is lower left, lower right, upper right, upper left. The points are relative to the text regardless of the angle, so "upper left" means in the top left-hand corner when you see the text horizontallty.

This example script will produce a black GIF 400x30 pixels, with the words "Testing..." in white in the font Arial.

Příklad 1. imagettftext

<?php header ("Content-type: image/gif"); $im = imagecreate (400, 30); $black = imagecolorallocate ($im, 0, 0, 0); $white = imagecolorallocate ($im, 255, 255, 255); imagettftext ($im, 20, 0, 10, 20, $white, "/path/arial.ttf", "Testing...Omega: Ω"); imagegif ($im); imagedestroy ($im); ?>

This function requires both the GD library and the FreeType library.

imagetypes

(PHP 3 CVS only, PHP 4 >= 4.0.2)

imagetypes -- Return the image types supported by this PHP build

Description

int imagetypes ( void)

This function returns a bit-field corresponding to the image formats supported by the version of GD linked into PHP. The following bits are returned, IMG_GIF | IMG_JPG | IMG_PNG | IMG_WBMP. To check for PNG support, for example, do this:

Příklad 1. imagetypes

<?php if (imagetypes() & IMG_PNG) { echo "PNG Support is enabled"; } ?>

imagewbmp

(PHP 3>= 3.0.15, PHP 4 >= 4.0.1)

imagewbmp -- Output image to browser or file

Description

int imagewbmp ( resource image [, string filename [, int foreground]])

imagewbmp() creates the WBMP file in filename from the image image. The image argument is the return from the imagecreate() function.

Poznámka: WBMP support is only available if PHP was compiled against GD-1.8 or later.

Using the optional foreground parameter, you can set the foreground color. Use an identifier obtained from imagecolorallocate(). The default foreground color is black.

iptcembed

(PHP 3>= 3.0.7, PHP 4 )

iptcembed -- Embed binary IPTC data into a JPEG image

Description

array iptcembed ( string iptcdata, string jpeg_file_name [, int spool])

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

iptcparse

(PHP 3>= 3.0.6, PHP 4 )

iptcparse -- Parse a binary IPTC http://www.iptc.org/ block into single tags.

Description

Poznámka: The read_exif_data() function is an alias for exif_read_data().

XLIII. IMAP, POP3 and NNTP functions

Úvod

These functions are not limited to the IMAP protocol, despite their name. The underlying c-client library also supports NNTP, POP3 and local mailbox access methods.

Požadavky

This extension requires the c-client library to be installed. Grab the latest version from ftp://ftp.cac.washington.edu/imap/ and compile it.

Instalace

To get these functions to work, you have to compile PHP with --with-imap.

Then copy c-client/c-client.a to /usr/local/lib/libc-client.a or some other directory on your link path and copy c-client/c-client.h, c-client/imap4r1.h, c-client/rfc-882.h, c-client/mail.h and c-client/linkage.h to /usr/local/include or some other directory in your include path.

Poznámka: Depending how the c-client was configured, you might also need to add --with-imap-ssl=/path/to/openssl/ and/or --with-kerberos into the PHP configure line.

Konfigurace běhu

Toto rozšíření nemá definováno žádné konfigurační direktivy.

Typy prostředků

Předdefinované konstanty

Tyto konstanty jsou definovány tímto rozšířením a budou k dispozici pouze tehdy, bylo-li rozšíření zkompilováno společně s PHP nebo dynamicky zavedeno za běhu.

NIL (integer)
OP_DEBUG (integer)
OP_READONLY (integer)
OP_ANONYMOUS (integer)
OP_SHORTCACHE (integer)
OP_SILENT (integer)
OP_PROTOTYPE (integer)
OP_HALFOPEN (integer)
OP_EXPUNGE (integer)
OP_SECURE (integer)
CL_EXPUNGE (integer)
FT_UID (integer)
FT_PEEK (integer)
FT_NOT (integer)
FT_INTERNAL (integer)
FT_PREFETCHTEXT (integer)
ST_UID (integer)
ST_SILENT (integer)
ST_SET (integer)
CP_UID (integer)
CP_MOVE (integer)
SE_UID (integer)
SE_FREE (integer)
SE_NOPREFETCH (integer)
SO_FREE (integer)
SO_NOSERVER (integer)
SA_MESSAGES (integer)
SA_RECENT (integer)
SA_UNSEEN (integer)
SA_UIDNEXT (integer)
SA_UIDVALIDITY (integer)
SA_ALL (integer)
LATT_NOINFERIORS (integer)
LATT_NOSELECT (integer)
LATT_MARKED (integer)
LATT_UNMARKED (integer)
SORTDATE (integer)
SORTARRIVAL (integer)
SORTFROM (integer)
SORTSUBJECT (integer)
SORTTO (integer)
SORTCC (integer)
SORTSIZE (integer)
TYPETEXT (integer)
TYPEMULTIPART (integer)
TYPEMESSAGE (integer)
TYPEAPPLICATION (integer)
TYPEAUDIO (integer)
TYPEIMAGE (integer)
TYPEVIDEO (integer)
TYPEOTHER (integer)
ENC7BIT (integer)
ENC8BIT (integer)
ENCBINARY (integer)
ENCBASE64 (integer)
ENCQUOTEDPRINTABLE (integer)
ENCOTHER (integer)

Viz také

This document can't go into detail on all the topics touched by the provided functions. Further information is provided by the documentation of the c-client library source (docs/internal.txt). and the following RFC documents:

RFC2821: Simple Mail Transfer Protocol (SMTP).
RFC2822: Standard for ARPA internet text messages.
RFC2060: Internet Message Access Protocol (IMAP) Version 4rev1.
RFC1939: Post Office Protocol Version 3 (POP3).
RFC977: Network News Transfer Protocol (NNTP).
RFC2076: Common Internet Message Headers.
RFC2045 , RFC2046 , RFC2047 , RFC2048 & RFC2049: Multipurpose Internet Mail Extensions (MIME).

A detailed overview is also available in the books Programming Internet Email by David Wood and Managing IMAP by Dianna Mullet & Kevin Mullet.

Varování

Crashes and startup problems of PHP may be encountered when loading this extension in conjunction with the recode extension. See the recode extension for more information.

Obsah
imap_8bit -- Convert an 8bit string to a quoted-printable string
imap_alerts -- This function returns all IMAP alert messages (if any) that have occurred during this page request or since the alert stack was reset
imap_append -- Append a string message to a specified mailbox
imap_base64 -- Decode BASE64 encoded text
imap_binary -- Convert an 8bit string to a base64 string
imap_body -- Read the message body
imap_bodystruct -- Read the structure of a specified body section of a specific message
imap_check -- Check current mailbox
imap_clearflag_full -- Clears flags on messages
imap_close -- Close an IMAP stream
imap_createmailbox -- Create a new mailbox
imap_delete -- Mark a messge for deletion from current mailbox
imap_deletemailbox -- Delete a mailbox
imap_errors -- This function returns all of the IMAP errors (if any) that have occurred during this page request or since the error stack was reset.
imap_expunge -- Delete all messages marked for deletion
imap_fetch_overview -- Read an overview of the information in the headers of the given message
imap_fetchbody -- Fetch a particular section of the body of the message
imap_fetchheader -- Returns header for a message
imap_fetchstructure -- Read the structure of a particular message
imap_get_quota -- Retrieve the quota level settings, and usage statics per mailbox
imap_getmailboxes -- Read the list of mailboxes, returning detailed information on each one
imap_getsubscribed -- List all the subscribed mailboxes
imap_header -- Read the header of the message
imap_headerinfo -- Read the header of the message
imap_headers -- Returns headers for all messages in a mailbox
imap_last_error -- This function returns the last IMAP error (if any) that occurred during this page request
imap_listmailbox -- Read the list of mailboxes
imap_listsubscribed -- List all the subscribed mailboxes
imap_mail_compose -- Create a MIME message based on given envelope and body sections
imap_mail_copy -- Copy specified messages to a mailbox
imap_mail_move -- Move specified messages to a mailbox
imap_mail -- Send an email message
imap_mailboxmsginfo -- Get information about the current mailbox
imap_mime_header_decode -- Decode MIME header elements
imap_msgno -- This function returns the message sequence number for the given UID
imap_num_msg -- Gives the number of messages in the current mailbox
imap_num_recent -- Gives the number of recent messages in current mailbox
imap_open -- Open an IMAP stream to a mailbox
imap_ping -- Check if the IMAP stream is still active
imap_popen -- Open a persistant IMAP stream to a mailbox
imap_qprint -- Convert a quoted-printable string to an 8 bit string
imap_renamemailbox -- Rename an old mailbox to new mailbox
imap_reopen -- Reopen IMAP stream to new mailbox
imap_rfc822_parse_adrlist -- Parses an address string
imap_rfc822_parse_headers -- Parse mail headers from a string
imap_rfc822_write_address -- Returns a properly formatted email address given the mailbox, host, and personal info.
imap_scanmailbox -- Read the list of mailboxes, takes a string to search for in the text of the mailbox
imap_search -- This function returns an array of messages matching the given search criteria
imap_set_quota -- Sets a quota for a given mailbox
imap_setacl -- Sets the ACL for a giving mailbox
imap_setflag_full -- Sets flags on messages
imap_sort -- Sort an array of message headers
imap_status -- This function returns status information on a mailbox other than the current one
imap_subscribe -- Subscribe to a mailbox
imap_thread -- Return threaded by REFERENCES tree
imap_uid -- This function returns the UID for the given message sequence number
imap_undelete -- Unmark the message which is marked deleted
imap_unsubscribe -- Unsubscribe from a mailbox
imap_utf7_decode -- Decodes a modified UTF-7 encoded string.
imap_utf7_encode -- Converts 8bit data to modified UTF-7 text.
imap_utf8 -- Converts text to UTF8

imap_8bit

(PHP 3, PHP 4 )

imap_8bit -- Convert an 8bit string to a quoted-printable string

Description

string imap_8bit ( string string)

string imap_binary ( string string)

Convert an 8bit string to a base64 string (according to RFC2045, Section 6.8).

Returns a base64 string.

imap_body

(PHP 3, PHP 4 )

imap_body -- Read the message body

Description

string imap_body ( int imap_stream, int msg_number [, int flags])

imap_body() returns the body of the message, numbered msg_number in the current mailbox. The optional flags are a bit mask with one or more of the following:

FT_UID - The msgno is a UID
FT_PEEK - Do not set the \Seen flag if not already set
FT_INTERNAL - The return string is in internal format, will not canonicalize to CRLF.

imap_body() will only return a verbatim copy of the message body. To extract single parts of a multipart MIME-encoded message you have to use imap_fetchstructure() to analyze its structure and imap_fetchbody() to extract a copy of a single body component.

imap_bodystruct

(PHP 3>= 3.0.4, PHP 4 )

imap_bodystruct -- Read the structure of a specified body section of a specific message

Description

int imap_deletemailbox ( int imap_stream, string mbox)

imap_deletemailbox() deletes the specified mailbox (see imap_open() for the format of mbox names).

Returns TRUE on success and FALSE on error.

See also imap_createmailbox(), imap_renamemailbox(), and imap_open() for the format of mbox.

imap_errors

(PHP 3>= 3.0.12, PHP 4 )

imap_errors -- This function returns all of the IMAP errors (if any) that have occurred during this page request or since the error stack was reset.

Description

array imap_errors ( void)

This function returns an array of all of the IMAP error messages generated since the last imap_errors() call, or the beginning of the page. When imap_errors() is called, the error stack is subsequently cleared.

imap_expunge

(PHP 3, PHP 4 )

imap_expunge -- Delete all messages marked for deletion

Description

This function fetches all the structured information for a given message. The optional flags parameter only has a single option, FT_UID, which tells the function to treat the msg_number argument as a UID. The returned object includes the envelope, internal date, size, flags and body structure along with a similar object for each mime attachement. The structure of the returned objects is as follows:

Tabulka 1. Returned Objects for imap_fetchstructure()

type	Primary body type
encoding	Body transfer encoding
ifsubtype	`TRUE` if there is a subtype string
subtype	MIME subtype
ifdescription	`TRUE` if there is a description string
description	Content description string
ifid	`TRUE` if there is an identification string
id	Identification string
lines	Number of lines
bytes	Number of bytes
ifdisposition	`TRUE` if there is a disposition string
disposition	Disposition string
ifdparameters	`TRUE` if the dparameters array exists
dparameters	An array of objects where each object has an "attribute" and a "value" property corresponding to the parameters on the Content-disposition MIMEheader.
ifparameters	`TRUE` if the parameters array exists
parameters	An array of objects where each object has an "attribute" and a "value" property.
parts	An array of objects identical in structure to the top-level object, each of which corresponds to a MIME body part.

Tabulka 2. Primary body type

0	text
1	multipart
2	message
3	application
4	audio
5	image
6	video
7	other

Tabulka 3. Transfer encodings

0	7BIT
1	8BIT
2	BINARY
3	BASE64
4	QUOTED-PRINTABLE
5	OTHER

imap_get_quota

(PHP 4 >= 4.0.5)

imap_get_quota -- Retrieve the quota level settings, and usage statics per mailbox

Description

array imap_get_quota ( int imap_stream, string quota_root)

Returns an array with integer values limit and usage for the given mailbox. The value of limit represents the total amount of space allowed for this mailbox. The usage value represents the mailboxes current level of capacity. Will return FALSE in the case of failure.

This function is currently only available to users of the c-client2000 library.

imap_stream should be the value returned from an imap_status() call. This stream is required to be opened as the mail admin user for the quota function to work. quota_root should normally be in the form of user.name where name is the mailbox you wish to retrieve information about.

Příklad 1. imap_get_quota() example

$mbox = imap_open("{your.imap.host}","mailadmin","password",OP_HALFOPEN) or die("can't connect: ".imap_last_error()); $quota_value = imap_get_quota($mbox, "user.kalowsky"); if(is_array($quota_value)) { print "Usage level is: " . $quota_value['usage']; print "Limit level is: " . $quota_value['limit']; } imap_close($mbox);

imap_getmailboxes

(PHP 3>= 3.0.12, PHP 4 )

imap_getmailboxes -- Read the list of mailboxes, returning detailed information on each one

Description

array imap_getmailboxes ( int imap_stream, string ref, string pattern)

Returns an array of objects containing mailbox information. Each object has the attributes name, specifying the full name of the mailbox; delimiter, which is the hierarchy delimiter for the part of the hierarchy this mailbox is in; and attributes. Attributes is a bitmask that can be tested against:

LATT_NOINFERIORS - This mailbox has no "children" (there are no mailboxes below this one).
LATT_NOSELECT - This is only a container, not a mailbox - you cannot open it.
LATT_MARKED - This mailbox is marked. Only used by UW-IMAPD.
LATT_UNMARKED - This mailbox is not marked. Only used by UW-IMAPD.

Mailbox names containing international Characters outside the printable ASCII range will be encoded and may be decoded by imap_utf7_decode().

ref should normally be just the server specification as described in imap_open(), and pattern specifies where in the mailbox hierarchy to start searching. If you want all mailboxes, pass '*' for pattern.

object imap_headerinfo ( int imap_stream, int msg_number [, int fromlength [, int subjectlength [, string defaulthost]]])

array imap_listmailbox ( int imap_stream, string ref, string pattern)

int imap_mail_copy ( int imap_stream, string msglist, string mbox [, int flags])

Returns TRUE on success and FALSE on error.

Copies mail messages specified by msglist to specified mailbox. msglist is a range not just message numbers (as described in RFC2060).

Flags is a bitmask of one or more of

CP_UID - the sequence numbers contain UIDS
CP_MOVE - Delete the messages from the current mailbox after copying

imap_mail_move

(PHP 3, PHP 4 )

imap_mail_move -- Move specified messages to a mailbox

Description

int imap_mail_move ( int imap_stream, string msglist, string mbox [, int flags])

Moves mail messages specified by msglist to specified mailbox. msglist is a range not just message numbers (as described in RFC2060).

Flags is a bitmask and may contain the single option

CP_UID - the sequence numbers contain UIDS

Returns TRUE on success and FALSE on error.

imap_mail

(PHP 3>= 3.0.14, PHP 4 )

imap_mail -- Send an email message

Description

string imap_mail ( string to, string subject, string message [, string additional_headers [, string cc [, string bcc [, string rpath]]]])

This function allows sending of emails with correct handling of Cc and Bcc receivers. The parameters to, cc and bcc are all strings and are all parsed as rfc822 address lists. The receivers specified in bcc will get the mail, but are excluded from the headers. Use the rpath parameter to specify return path. This is useful when using php as a mail client for multiple users.

imap_mailboxmsginfo

(PHP 3>= 3.0.2, PHP 4 )

imap_mailboxmsginfo -- Get information about the current mailbox

Description

object imap_mailboxmsginfo ( int imap_stream)

Returns information about the current mailbox. Returns FALSE on failure.

The imap_mailboxmsginfo() function checks the current mailbox status on the server. It is similar to imap_status(), but will additionally sum up the size of all messages in the mailbox, which will take some additional time to execute. It returns the information in an object with following properties.

Tabulka 1. Mailbox properties

Date	date of last change
Driver	driver
Mailbox	name of the mailbox
Nmsgs	number of messages
Recent	number of recent messages
Unread	number of unread messages
Deleted	number of deleted messages
Size	mailbox size

Příklad 1. imap_mailboxmsginfo() example

<?php $mbox = imap_open("{your.imap.host}INBOX","username", "password") or die("can't connect: ".imap_last_error()); $check = imap_mailboxmsginfo($mbox); if($check) { print "Date: " . $check->Date ."<br>\n" ; print "Driver: " . $check->Driver ."<br>\n" ; print "Mailbox: " . $check->Mailbox ."<br>\n" ; print "Messages: ". $check->Nmsgs ."<br>\n" ; print "Recent: " . $check->Recent ."<br>\n" ; print "Unread: " . $check->Unread ."<br>\n" ; print "Deleted: " . $check->Deleted ."<br>\n" ; print "Size: " . $check->Size ."<br>\n" ; } else { print "imap_check() failed: ".imap_last_error(). "<br>\n"; } imap_close($mbox); ?>

imap_mime_header_decode

(PHP 3>= 3.0.17, PHP 4 )

imap_mime_header_decode -- Decode MIME header elements

Description

array imap_mime_header_decode ( string text)

imap_mime_header_decode() function decodes MIME message header extensions that are non ASCII text (see RFC2047) The decoded elements are returned in an array of objects, where each object has two properties, "charset" & "text". If the element hasn't been encoded, and in other words is in plain US-ASCII,the "charset" property of that element is set to "default".

int imap_num_recent ( int imap_stream)

Returns the number of recent messages in the current mailbox.

See also: imap_num_msg() and imap_status().

imap_open

(PHP 3, PHP 4 )

imap_open -- Open an IMAP stream to a mailbox

Description

int imap_open ( string mailbox, string username, string password [, int flags])

Returns an IMAP stream on success and FALSE on error. This function can also be used to open streams to POP3 and NNTP servers, but some functions and features are only available on IMAP servers.

A mailbox name consists of a server part and a mailbox path on this server. The special name INBOX stands for the current users personal mailbox. The server part, which is enclosed in '{' and '}', consists of the servers name or ip address, an optional port (prefixed by ':'), and an optional protocol specification (prefixed by '/'). The server part is mandatory in all mailbox parameters. Mailbox names that contain international characters besides those in the printable ASCII space have to be encoded with imap_utf7_encode().

The options are a bit mask with one or more of the following:

OP_READONLY - Open mailbox read-only
OP_ANONYMOUS - Dont use or update a .newsrc for news (NNTP only)
OP_HALFOPEN - For IMAP and NNTP names, open a connection but dont open a mailbox
CL_EXPUNGE - Expunge mailbox automatically upon mailbox close

To connect to an IMAP server running on port 143 on the local machine, do the following:

$mbox = imap_open ("{localhost:143}INBOX", "user_id", "password");

To connect to a POP3 server on port 110 on the local server, use:

$mbox = imap_open ("{localhost:110/pop3}INBOX", "user_id", "password");

To connect to an SSL IMAP or POP3 server, add /ssl after the protocol specification:

$mbox = imap_open ("{localhost:993/imap/ssl}INBOX", "user_id", "password");

To connect to an SSL IMAP or POP3 server with a self-signed certificate, add /ssl/novalidate-cert after the protocol specification:

$mbox = imap_open ("{localhost:995/pop3/ssl/novalidate-cert}", "user_id", "password");

To connect to an NNTP server on port 119 on the local server, use:

$nntp = imap_open ("{localhost:119/nntp}comp.test", "", "");

This function renames on old mailbox to new mailbox (see imap_open() for the format of mbox names).

Returns TRUE on success and FALSE on error.

See also imap_createmailbox(), imap_deletemailbox(), and imap_open() for the format of mbox.

imap_reopen

(PHP 3, PHP 4 )

imap_reopen -- Reopen IMAP stream to new mailbox

Description

int imap_reopen ( int imap_stream, string mailbox [, string flags])

This function reopens the specified stream to a new mailbox on an IMAP or NNTP server.

The options are a bit mask with one or more of the following:

OP_READONLY - Open mailbox read-only
OP_ANONYMOUS - Dont use or update a .newsrc for news (NNTP only)
OP_HALFOPEN - For IMAP and NNTP names, open a connection but dont open a mailbox.
CL_EXPUNGE - Expunge mailbox automatically upon mailbox close (see also imap_delete() and imap_expunge())

Returns TRUE on success and FALSE on error.

imap_rfc822_parse_adrlist

(PHP 3>= 3.0.2, PHP 4 )

imap_rfc822_parse_adrlist -- Parses an address string

Description

array imap_rfc822_parse_adrlist ( string address, string default_host)

This function parses the address string as defined in RFC2822 and for each address, returns an array of objects. The objects properties are:

mailbox - the mailbox name (username)
host - the host name
personal - the personal name
adl - at domain source route

Příklad 1. imap_rfc822_parse_adrlist() example

$address_string = "Hartmut Holzgraefe <hartmut@cvs.php.net>, postmaster@somedomain.net, root"; $address_array = imap_rfc822_parse_adrlist($address_string,"somedomain.net"); if(! is_array($address_array)) die("somethings wrong\n"); reset($address_array); while(list($key,$val)=each($address_array)){ print "mailbox : ".$val->mailbox."<br>\n"; print "host : ".$val->host."<br>\n"; print "personal: ".$val->personal."<br>\n"; print "adl : ".$val->adl."<p>\n"; }

imap_rfc822_parse_headers

(PHP 4 )

imap_rfc822_parse_headers -- Parse mail headers from a string

Description

object imap_rfc822_parse_headers ( string headers [, string defaulthost])

This function returns an object of various header elements, similar to imap_header(), except without the flags and other elements that come from the IMAP server.

imap_rfc822_write_address

(PHP 3>= 3.0.2, PHP 4 )

imap_rfc822_write_address -- Returns a properly formatted email address given the mailbox, host, and personal info.

Description

string imap_rfc822_write_address ( string mailbox, string host, string personal)

Returns a properly formatted email address as defined in RFC2822 given the mailbox, host, and personal info.

Příklad 1. imap_rfc822_write_address() example

print imap_rfc822_write_address("hartmut","cvs.php.net","Hartmut Holzgraefe")."\n";

imap_scanmailbox

(PHP 3, PHP 4 )

imap_scanmailbox -- Read the list of mailboxes, takes a string to search for in the text of the mailbox

Description

array imap_scanmailbox ( int imap_stream, string ref, string pattern, string content)

Returns an array containing the names of the mailboxes that have content in the text of the mailbox. This function is similar to imap_listmailbox(), but it will additionally check for the presence of the string content inside the mailbox data. See imap_getmailboxes() for a description of ref and pattern.

imap_search

(PHP 3>= 3.0.12, PHP 4 )

imap_search -- This function returns an array of messages matching the given search criteria

Description

array imap_search ( int imap_stream, string criteria, int flags)

This function performs a search on the mailbox currently opened in the given imap stream. criteria is a string, delimited by spaces, in which the following keywords are allowed. Any multi-word arguments (eg. FROM "joey smith") must be quoted.

ALL - return all messages matching the rest of the criteria
ANSWERED - match messages with the \\ANSWERED flag set
BCC "string" - match messages with "string" in the Bcc: field
BEFORE "date" - match messages with Date: before "date"
BODY "string" - match messages with "string" in the body of the message
CC "string" - match messages with "string" in the Cc: field
DELETED - match deleted messages
FLAGGED - match messages with the \\FLAGGED (sometimes referred to as Important or Urgent) flag set
FROM "string" - match messages with "string" in the From: field
KEYWORD "string" - match messages with "string" as a keyword
NEW - match new messages
OLD - match old messages
ON "date" - match messages with Date: matching "date"
RECENT - match messages with the \\RECENT flag set
SEEN - match messages that have been read (the \\SEEN flag is set)
SINCE "date" - match messages with Date: after "date"
SUBJECT "string" - match messages with "string" in the Subject:
TEXT "string" - match messages with text "string"
TO "string" - match messages with "string" in the To:
UNANSWERED - match messages that have not been answered
UNDELETED - match messages that are not deleted
UNFLAGGED - match messages that are not flagged
UNKEYWORD "string" - match messages that do not have the keyword "string"
UNSEEN - match messages which have not been read yet

For example, to match all unanswered messages sent by Mom, you'd use: "UNANSWERED FROM mom". Searches appear to be case insensitive. This list of criteria is from a reading of the UW c-client source code and may be uncomplete or inaccurate (see also RFC2060, section 6.4.4).

Valid values for flags are SE_UID, which causes the returned array to contain UIDs instead of messages sequence numbers.

imap_set_quota

(PHP 4 >= 4.0.5)

imap_set_quota -- Sets a quota for a given mailbox

Description

int imap_set_quota ( int imap_stream, string quota_root, int quota_limit)

Sets an upper limit quota on a per mailbox basis. This function requires the imap_stream to have been opened as the mail administrator account. It will not work if opened as any other user.

This function is currently only available to users of the c-client2000 library.

imap_stream is the stream pointer returned from a imap_open() call. This stream must be opened as the mail administrator, other wise this function will fail. quota_root is the mailbox to have a quota set. This should follow the IMAP standard format for a mailbox, 'user.name'. quota_limit is the maximum size (in KB) for the quota_root.

Returns TRUE on success and FALSE on error.

Příklad 1. imap_set_quota() example

$mbox = imap_open ("{your.imap.host:143}", "mailadmin", "password"); if(!imap_set_quota($mbox, "user.kalowsky", 3000)) { print "Error in setting quota\n"; return; } imap_close($mbox);

See also imap_open(), imap_set_quota().

imap_setacl

(PHP 4 >= 4.1.0)

imap_setacl -- Sets the ACL for a giving mailbox

Description

int imap_setacl ( int stream_id, string mailbox, string id, string rights)

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

imap_setflag_full

(PHP 3>= 3.0.3, PHP 4 )

imap_setflag_full -- Sets flags on messages

Description

string imap_setflag_full ( int stream, string sequence, string flag, string options)

This function causes a store to add the specified flag to the flags set for the messages in the specified sequence.

The flags which you can set are "\\Seen", "\\Answered", "\\Flagged", "\\Deleted", and "\\Draft" (as defined by RFC2060).

The options are a bit mask with one or more of the following:

ST_UID          The sequence argument contains UIDs instead of
                sequence numbers

Příklad 1. imap_setflag_full() example

$mbox = imap_open("{your.imap.host:143}","username","password") or die("can't connect: ".imap_last_error()); $status = imap_setflag_full($mbox,"2,5","\\Seen \\Flagged"); print gettype($status)."\n"; print $status."\n"; imap_close($mbox);

imap_sort

(PHP 3>= 3.0.3, PHP 4 )

imap_sort -- Sort an array of message headers

Description

array imap_sort ( int stream, int criteria, int reverse, int options)

Returns an array of message numbers sorted by the given parameters.

Reverse is 1 for reverse-sorting.

Criteria can be one (and only one) of the following:

SORTDATE        message Date
SORTARRIVAL     arrival date
SORTFROM        mailbox in first From address
SORTSUBJECT     message Subject
SORTTO          mailbox in first To address
SORTCC          mailbox in first cc address
SORTSIZE        size of message in octets

The flags are a bitmask of one or more of the following:

SE_UID          Return UIDs instead of sequence numbers
SE_NOPREFETCH   Don't prefetch searched messages.

imap_status

(PHP 3>= 3.0.4, PHP 4 )

imap_status -- This function returns status information on a mailbox other than the current one

Description

object imap_status ( int imap_stream, string mailbox, int options)

This function returns an object containing status information. Valid flags are:

SA_MESSAGES - set status->messages to the number of messages in the mailbox
SA_RECENT - set status->recent to the number of recent messages in the mailbox
SA_UNSEEN - set status->unseen to the number of unseen (new) messages in the mailbox
SA_UIDNEXT - set status->uidnext to the next uid to be used in the mailbox
SA_UIDVALIDITY - set status->uidvalidity to a constant that changes when uids for the mailbox may no longer be valid
SA_ALL - set all of the above

Converts the given text to UTF8 (as defined in RFC2044).

XLIV. Informix functions

Úvod

The Informix driver for Informix (IDS) 7.x, SE 7.x, Universal Server (IUS) 9.x and IDS 2000 is implemented in "ifx.ec" and "php3_ifx.h" in the informix extension directory. IDS 7.x support is fairly complete, with full support for BYTE and TEXT columns. IUS 9.x support is partly finished: the new data types are there, but SLOB and CLOB support is still under construction.

Požadavky

Configuration notes: You need a version of ESQL/C to compile the PHP Informix driver. ESQL/C versions from 7.2x on should be OK. ESQL/C is now part of the Informix Client SDK.

Make sure that the "INFORMIXDIR" variable has been set, and that $INFORMIXDIR/bin is in your PATH before you run the "configure" script.

Instalace

Poznámka: The configure script will autodetect the libraries and include directories, if you run configure --with_informix=yes. You can override this detection by specifying "IFX_LIBDIR", "IFX_LIBS" and "IFX_INCDIR" in the environment. The configure script will also try to detect your Informix server version. It will set the "HAVE_IFX_IUS" conditional compilation variable if your Informix version >= 9.00.

Konfigurace běhu

Poznámka: Make sure that the Informix environment variables INFORMIXDIR and INFORMIXSERVER are available to the PHP ifx driver, and that the INFORMIX bin directory is in the PATH. Check this by running a script that contains a call to phpinfo() before you start testing. The phpinfo() output should list these environment variables. This is TRUE for both CGI php and Apache mod_php. You may have to set these environment variables in your Apache startup script.

The Informix shared libraries should also be available to the loader (check LD_LINBRARY_PATH or ld.so.conf/ldconfig).

Some notes on the use of BLOBs (TEXT and BYTE columns): BLOBs are normally addressed by BLOB identifiers. Select queries return a "blob id" for every BYTE and TEXT column. You can get at the contents with "string_var = ifx_get_blob($blob_id);" if you choose to get the BLOBs in memory (with : "ifx_blobinfile(0);"). If you prefer to receive the content of BLOB columns in a file, use "ifx_blobinfile(1);", and "ifx_get_blob($blob_id);" will get you the filename. Use normal file I/O to get at the blob contents.

For insert/update queries you must create these "blob id's" yourself with "ifx_create_blob();". You then plug the blob id's into an array, and replace the blob columns with a question mark (?) in the query string. For updates/inserts, you are responsible for setting the blob contents with ifx_update_blob().

The behaviour of BLOB columns can be altered by configuration variables that also can be set at runtime :

configuration variable : ifx.textasvarchar

configuration variable : ifx.byteasvarchar

runtime functions :

ifx_textasvarchar(0) : use blob id's for select queries with TEXT columns

ifx_byteasvarchar(0) : use blob id's for select queries with BYTE columns

ifx_textasvarchar(1) : return TEXT columns as if they were VARCHAR columns, so that you don't need to use blob id's for select queries.

ifx_byteasvarchar(1) : return BYTE columns as if they were VARCHAR columns, so that you don't need to use blob id's for select queries.

configuration variable : ifx.blobinfile

runtime function :

ifx_blobinfile_mode(0) : return BYTE columns in memory, the blob id lets you get at the contents.

ifx_blobinfile_mode(1) : return BYTE columns in a file, the blob id lets you get at the file name.

If you set ifx_text/byteasvarchar to 1, you can use TEXT and BYTE columns in select queries just like normal (but rather long) VARCHAR fields. Since all strings are "counted" in PHP, this remains "binary safe". It is up to you to handle this correctly. The returned data can contain anything, you are responsible for the contents.

If you set ifx_blobinfile to 1, use the file name returned by ifx_get_blob(..) to get at the blob contents. Note that in this case YOU ARE RESPONSIBLE FOR DELETING THE TEMPORARY FILES CREATED BY INFORMIX when fetching the row. Every new row fetched will create new temporary files for every BYTE column.

The location of the temporary files can be influenced by the environment variable "blobdir", default is "." (the current directory). Something like : putenv(blobdir=tmpblob"); will ease the cleaning up of temp files accidentally left behind (their names all start with "blb").

Automatically trimming "char" (SQLCHAR and SQLNCHAR) data: This can be set with the configuration variable

ifx.charasvarchar : if set to 1 trailing spaces will be automatically trimmed, to save you some "chopping".

NULL values: The configuration variable ifx.nullformat (and the runtime function ifx_nullformat()) when set to TRUE will return NULL columns as the string "NULL", when set to FALSE they return the empty string. This allows you to discriminate between NULL columns and empty columns.

Typy prostředků

Předdefinované konstanty

Toto rozšíření nemá definovány žádné konstanty.

Obsah
ifx_affected_rows -- Get number of rows affected by a query
ifx_blobinfile_mode -- Set the default blob mode for all select queries
ifx_byteasvarchar -- Set the default byte mode
ifx_close -- Close Informix connection
ifx_connect -- Open Informix server connection
ifx_copy_blob -- Duplicates the given blob object
ifx_create_blob -- Creates an blob object
ifx_create_char -- Creates an char object
ifx_do -- Execute a previously prepared SQL-statement
ifx_error -- Returns error code of last Informix call
ifx_errormsg -- Returns error message of last Informix call
ifx_fetch_row -- Get row as enumerated array
ifx_fieldproperties -- List of SQL fieldproperties
ifx_fieldtypes -- List of Informix SQL fields
ifx_free_blob -- Deletes the blob object
ifx_free_char -- Deletes the char object
ifx_free_result -- Releases resources for the query
ifx_get_blob -- Return the content of a blob object
ifx_get_char -- Return the content of the char object
ifx_getsqlca -- Get the contents of sqlca.sqlerrd[0..5] after a query
ifx_htmltbl_result -- Formats all rows of a query into a HTML table
ifx_nullformat -- Sets the default return value on a fetch row
ifx_num_fields -- Returns the number of columns in the query
ifx_num_rows -- Count the rows already fetched from a query
ifx_pconnect -- Open persistent Informix connection
ifx_prepare -- Prepare an SQL-statement for execution
ifx_query -- Send Informix query
ifx_textasvarchar -- Set the default text mode
ifx_update_blob -- Updates the content of the blob object
ifx_update_char -- Updates the content of the char object
ifxus_close_slob -- Deletes the slob object
ifxus_create_slob -- Creates an slob object and opens it
ifxus_free_slob -- Deletes the slob object
ifxus_open_slob -- Opens an slob object
ifxus_read_slob -- Reads nbytes of the slob object
ifxus_seek_slob -- Sets the current file or seek position
ifxus_tell_slob -- Returns the current file or seek position
ifxus_write_slob -- Writes a string into the slob object

ifx_affected_rows

(PHP 3>= 3.0.3, PHP 4 )

ifx_affected_rows -- Get number of rows affected by a query

Description

int ifx_affected_rows ( int result_id)

result_id is a valid result id returned by ifx_query() or ifx_prepare().

Returns the number of rows affected by a query associated with result_id.

For inserts, updates and deletes the number is the real number (sqlerrd[2]) of affected rows. For selects it is an estimate (sqlerrd[0]). Don't rely on it. The database server can never return the actual number of rows that will be returned by a SELECT because it has not even begun fetching them at this stage (just after the "PREPARE" when the optimizer has determined the query plan).

Useful after ifx_prepare() to limit queries to reasonable result sets.

ifx_blobinfile_mode

(PHP 3>= 3.0.4, PHP 4 )

ifx_blobinfile_mode -- Set the default blob mode for all select queries

Description

void ifx_blobinfile_mode ( int mode)

Set the default blob mode for all select queries. Mode "0" means save Byte-Blobs in memory, and mode "1" means save Byte-Blobs in a file.

ifx_byteasvarchar

ifx_do -- Execute a previously prepared SQL-statement

Description

int ifx_do ( int result_id)

Returns TRUE on success, FALSE on error.

Executes a previously prepared query or opens a cursor for it.

Does NOT free result_id on error.

Also sets the real number of ifx_affected_rows() for non-select statements for retrieval by ifx_affected_rows()

See also: ifx_prepare(). There is a example.

ifx_error

(PHP 3>= 3.0.3, PHP 4 )

ifx_error -- Returns error code of last Informix call

Description

string ifx_error ( void)

The Informix error codes (SQLSTATE & SQLCODE) formatted as follows :

x [SQLSTATE = aa bbb SQLCODE=cccc]

where x = space : no error

E : error

N : no more data

W : warning

? : undefined

If the "x" character is anything other than space, SQLSTATE and SQLCODE describe the error in more detail.

See the Informix manual for the description of SQLSTATE and SQLCODE

Returns in a string one character describing the general results of a statement and both SQLSTATE and SQLCODE associated with the most recent SQL statement executed. The format of the string is "(char) [SQLSTATE=(two digits) (three digits) SQLCODE=(one digit)]". The first character can be ' ' (space) (success), 'W' (the statement caused some warning), 'E' (an error happened when executing the statement) or 'N' (the statement didn't return any data).

ifx_errormsg

(PHP 3>= 3.0.4, PHP 4 )

ifx_errormsg -- Returns error message of last Informix call

Description

string ifx_errormsg ( [int errorcode])

Returns the Informix error message associated with the most recent Informix error, or, when the optional "errorcode" param is present, the error message corresponding to "errorcode".

ifx_fetch_row

(PHP 3>= 3.0.3, PHP 4 )

ifx_fetch_row -- Get row as enumerated array

Description

array ifx_fetch_row ( int result_id [, mixed position])

Returns an associative array that corresponds to the fetched row, or FALSE if there are no more rows.

Blob columns are returned as integer blob id values for use in ifx_get_blob() unless you have used ifx_textasvarchar(1) or ifx_byteasvarchar(1), in which case blobs are returned as string values. Returns FALSE on error

result_id is a valid resultid returned by ifx_query() or ifx_prepare() (select type queries only!).

position is an optional parameter for a "fetch" operation on "scroll" cursors: "NEXT", "PREVIOUS", "CURRENT", "FIRST", "LAST" or a number. If you specify a number, an "absolute" row fetch is executed. This parameter is optional, and only valid for SCROLL cursors.

ifx_fetch_row() fetches one row of data from the result associated with the specified result identifier. The row is returned as an array. Each result column is stored in an array offset, starting at offset 0, with the column name as key.

Subsequent calls to ifx_fetch_row() would return the next row in the result set, or FALSE if there are no more rows.

Příklad 1. Informix fetch rows

$rid = ifx_prepare ("select * from emp where name like " . $name,
                     $connid, IFX_SCROLL);
if (! $rid) {
    ... error ...
}
$rowcount = ifx_affected_rows($rid);
if ($rowcount > 1000) {
    printf ("Too many rows in result set (%d)\n<br>", $rowcount);
    die ("Please restrict your query<br>\n");
}
if (! ifx_do ($rid)) {
   ... error ...
}
$row = ifx_fetch_row ($rid, "NEXT");
while (is_array($row)) {
    for(reset($row); $fieldname=key($row); next($row)) {
        $fieldvalue = $row[$fieldname];
        printf ("%s = %s,", $fieldname, $fieldvalue);
    }
    printf("\n<br>");
    $row = ifx_fetch_row ($rid, "NEXT");
}
ifx_free_result ($rid);

ifx_fieldproperties

(PHP 3>= 3.0.3, PHP 4 )

ifx_fieldproperties -- List of SQL fieldproperties

Description

array ifx_fieldproperties ( int result_id)

Returns an associative array with fieldnames as key and the SQL fieldproperties as data for a query with result_id. Returns FALSE on error.

Returns the Informix SQL fieldproperties of every field in the query as an associative array. Properties are encoded as: "SQLTYPE;length;precision;scale;ISNULLABLE" where SQLTYPE = the Informix type like "SQLVCHAR" etc. and ISNULLABLE = "Y" or "N".

Příklad 1. Informix SQL fieldproperties

$properties = ifx_fieldproperties ($resultid);
if (! isset($properties)) {
  ... error ...
}
for ($i = 0; $i < count($properties); $i++) {
    $fname = key ($properties);
    printf ("%s:\t type =  %s\n", $fname, $properties[$fname]);
    next ($properties);
}

ifx_fieldtypes

(PHP 3>= 3.0.3, PHP 4 )

ifx_fieldtypes -- List of Informix SQL fields

Description

array ifx_fieldtypes ( int result_id)

Returns an associative array with fieldnames as key and the SQL fieldtypes as data for query with result_id. Returns FALSE on error.

Příklad 1. Fieldnames and SQL fieldtypes

$types = ifx_fieldtypes ($resultid);
if (! isset ($types)) {
  ... error ...
}
for ($i = 0; $i < count($types); $i++) {
    $fname = key($types);
    printf("%s :\t type =  %s\n", $fname, $types[$fname]);
    next($types);
}

Returns a pseudo-row (associative array) with sqlca.sqlerrd[0] ... sqlca.sqlerrd[5] after the query associated with result_id.

For inserts, updates and deletes the values returned are those as set by the server after executing the query. This gives access to the number of affected rows and the serial insert value. For SELECTs the values are those saved after the PREPARE statement. This gives access to the *estimated* number of affected rows. The use of this function saves the overhead of executing a "select dbinfo('sqlca.sqlerrdx')" query, as it retrieves the values that were saved by the ifx driver at the appropriate moment.

Příklad 1. Retrieve Informix sqlca.sqlerrd[x] values

/* assume the first column of 'sometable' is a serial */
$qid = ifx_query("insert into sometable 
                  values (0, '2nd column', 'another column') ", $connid);
if (! $qid) {
    ... error ...
}
$sqlca = ifx_getsqlca ($qid);
$serial_value = $sqlca["sqlerrd1"];
echo "The serial value of the inserted row is : " . $serial_value<br>\n";

ifx_htmltbl_result

(PHP 3>= 3.0.3, PHP 4 )

ifx_htmltbl_result -- Formats all rows of a query into a HTML table

Description

int ifx_htmltbl_result ( int result_id [, string html_table_options])

Returns the number of rows fetched or FALSE on error.

Formats all rows of the result_id query into a html table. The optional second argument is a string of <table> tag options

Příklad 1. Informix results as HTML table

$rid = ifx_prepare ("select * from emp where name like " . $name,
                     $connid, IFX_SCROLL);
if (! $rid) {
   ... error ...
}
$rowcount = ifx_affected_rows ($rid);
if ($rowcount > 1000) {
    printf ("Too many rows in result set (%d)\n<br>", $rowcount);
    die ("Please restrict your query<br>\n");
}
if (! ifx_do($rid) {
  ... error ...
}

ifx_htmltbl_result ($rid, "border=\"2\"");

ifx_free_result($rid);

ifx_nullformat

(PHP 3>= 3.0.4, PHP 4 )

ifx_nullformat -- Sets the default return value on a fetch row

Description

void ifx_nullformat ( int mode)

Sets the default return value of a NULL-value on a fetch row. Mode "0" returns "", and mode "1" returns "NULL".

ifx_num_fields

(PHP 3>= 3.0.3, PHP 4 )

ifx_num_fields -- Returns the number of columns in the query

Description

int ifx_num_fields ( int result_id)

Returns the number of columns in query for result_id or FALSE on error

After preparing or executing a query, this call gives you the number of columns in the query.

ifx_num_rows

(PHP 3>= 3.0.3, PHP 4 )

ifx_num_rows -- Count the rows already fetched from a query

Description

int ifx_num_rows ( int result_id)

Gives the number of rows fetched so far for a query with result_id after a ifx_query() or ifx_do() query.

ifx_pconnect

(PHP 3>= 3.0.3, PHP 4 )

ifx_pconnect -- Open persistent Informix connection

Description

int ifx_pconnect ( [string database [, string userid [, string password]]])

Returns: A positive Informix persistent link identifier on success, or FALSE on error

ifx_pconnect() acts very much like ifx_connect() with two major differences.

This function behaves exactly like ifx_connect() when PHP is not running as an Apache module. First, when connecting, the function would first try to find a (persistent) link that's already open with the same host, username and password. If one is found, an identifier for it will be returned instead of opening a new connection.

Second, the connection to the SQL server will not be closed when the execution of the script ends. Instead, the link will remain open for future use (ifx_close() will not close links established by ifx_pconnect()).

This type of links is therefore called 'persistent'.

ifx_prepare

(PHP 3>= 3.0.4, PHP 4 )

ifx_prepare -- Prepare an SQL-statement for execution

Description

int ifx_prepare ( string query, int conn_id [, int cursor_def, mixed blobidarray])

Returns a integer result_id for use by ifx_do(). Sets affected_rows for retrieval by the ifx_affected_rows() function.

Úvod

InterBase is a popular database put out by Borland/Inprise. More information about InterBase is available at http://www.interbase.com/. Oh, by the way, InterBase just joined the open source movement!

Poznámka: Full support for InterBase 6 was added in PHP 4.0.

This database uses a single quote (') character for escaping, a behavior similar to the Sybase database, add to your php.ini the following directive:
magic_quotes_sybase = On

Požadavky

Instalace

Konfigurace běhu

Typy prostředků

Předdefinované konstanty

Tyto konstanty jsou definovány tímto rozšířením a budou k dispozici pouze tehdy, bylo-li rozšíření zkompilováno společně s PHP nebo dynamicky zavedeno za běhu.

IBASE_DEFAULT (integer)
IBASE_TEXT (integer)
IBASE_UNIXTIME (integer)
IBASE_READ (integer)
IBASE_COMMITTED (integer)
IBASE_CONSISTENCY (integer)
IBASE_NOWAIT (integer)
IBASE_TIMESTAMP (integer)
IBASE_DATE (integer)
IBASE_TIME (integer)

Obsah
ibase_blob_add -- Add data into created blob
ibase_blob_cancel -- Cancel creating blob
ibase_blob_close -- Close blob
ibase_blob_create -- Create blob for adding data
ibase_blob_echo -- Output blob contents to browser
ibase_blob_get -- Get len bytes data from open blob
ibase_blob_import -- Create blob, copy file in it, and close it
ibase_blob_info -- Return blob length and other useful info
ibase_blob_open -- Open blob for retrieving data parts
ibase_close -- Close a connection to an InterBase database
ibase_commit -- Commit a transaction
ibase_connect -- Open a connection to an InterBase database
ibase_errmsg -- Returns error messages
ibase_execute -- Execute a previously prepared query
ibase_fetch_object -- Get an object from a InterBase database
ibase_fetch_row -- Fetch a row from an InterBase database
ibase_field_info -- Get information about a field
ibase_free_query -- Free memory allocated by a prepared query
ibase_free_result -- Free a result set
ibase_num_fields -- Get the number of fields in a result set
ibase_pconnect -- Creates an persistent connection to an InterBase database
ibase_prepare -- Prepare a query for later binding of parameter placeholders and execution
ibase_query -- Execute a query on an InterBase database
ibase_rollback -- Rolls back a transaction
ibase_timefmt -- Sets the format of timestamp, date and time type columns returned from queries
ibase_trans -- Begin a transaction

(PHP 3>= 3.0.7, PHP 4 )

ibase_commit -- Commit a transaction

Description

int ibase_commit ( [int link_identifier, int trans_number])

Commits transaction trans_number which was created with ibase_trans().

ibase_connect

(PHP 3>= 3.0.6, PHP 4 )

ibase_connect -- Open a connection to an InterBase database

Description

int ibase_connect ( string database [, string username [, string password [, string charset [, int buffers [, int dialect [, string role]]]]]])

Establishes a connection to an InterBase server. The database argument has to be a valid path to database file on the server it resides on. If the server is not local, it must be prefixed with either 'hostname:' (TCP/IP), '//hostname/' (NetBEUI) or 'hostname@' (IPX/SPX), depending on the connection protocol used. username and password can also be specified with PHP configuration directives ibase.default_user and ibase.default_password. charset is the default character set for a database. buffers is the number of database buffers to allocate for the server-side cache. If 0 or omitted, server chooses its own default. dialect selects the default SQL dialect for any statement executed within a connection, and it defaults to the highest one supported by client libraries.

In case a second call is made to ibase_connect() with the same arguments, no new link will be established, but instead, the link identifier of the already opened link will be returned. The link to the server will be closed as soon as the execution of the script ends, unless it's closed earlier by explicitly calling ibase_close().

Příklad 1. ibase_connect() example

<?php $dbh = ibase_connect($host, $username, $password); $stmt = 'SELECT * FROM tblname'; $sth = ibase_query($dbh, $stmt); while ($row = ibase_fetch_object($sth)) { echo $row->email, "\n"; } ibase_free_result($sth); ibase_close($dbh); ?>

Poznámka: buffers was added in PHP 4.0RC2.

Poznámka: dialect was added in PHP 4.0RC2. It is functional only with InterBase 6 and versions higher than that.

Poznámka: role was added in PHP 4.0RC2. It is functional only with InterBase 5 and versions higher than that.

ibase_errmsg

(PHP 3>= 3.0.7, PHP 4 )

ibase_errmsg -- Returns error messages

Description

string ibase_errmsg ( void)

Returns a string containing an error message.

ibase_execute

(PHP 3>= 3.0.6, PHP 4 )

ibase_execute -- Execute a previously prepared query

Description

int ibase_execute ( int query [, int bind_args])

Execute a query prepared by ibase_prepare(). This is a lot more effective than using ibase_query() if you are repeating a same kind of query several times with only some parameters changing.

<?php
    $updates = array(
        1 => 'Eric',
        5 => 'Filip',
        7 => 'Larry'
    );

    $query = ibase_prepare("UPDATE FOO SET BAR = ? WHERE BAZ = ?");

    while (list($baz, $bar) = each($updates)) {
        ibase_execute($query, $bar, $baz);
    }
?>

ibase_fetch_object

(PHP 3>= 3.0.7, PHP 4 )

ibase_fetch_object -- Get an object from a InterBase database

Description

object ibase_fetch_object ( int result_id)

Fetches a row as a pseudo-object from a result_id obtained either by ibase_query() or ibase_execute().

<php
    $dbh = ibase_connect ($host, $username, $password);
    $stmt = 'SELECT * FROM tblname';
    $sth = ibase_query ($dbh, $stmt);
    while ($row = ibase_fetch_object ($sth)) {
        print $row->email . "\n";
    }
    ibase_close ($dbh);
?>

Subsequent call to ibase_fetch_object() would return the next row in the result set, or FALSE if there are no more rows.

ibase_fetch_row

(PHP 3>= 3.0.6, PHP 4 )

ibase_fetch_row -- Fetch a row from an InterBase database

Description

array ibase_fetch_row ( int result_identifier)

Returns an array that corresponds to the fetched row, or FALSE if there are no more rows.

ibase_fetch_row() fetches one row of data from the result associated with the specified result_identifier. The row is returned as an array. Each result column is stored in an array offset, starting at offset 0.

Subsequent call to ibase_fetch_row() would return the next row in the result set, or FALSE if there are no more rows.

ibase_field_info

(PHP 3>= 3.0.7, PHP 4 )

ibase_field_info -- Get information about a field

Description

array ibase_field_info ( int result, int field number)

Returns an array with information about a field after a select query has been run. The array is in the form of name, alias, relation, length, type.

$rs=ibase_query("SELECT * FROM tablename"); 
$coln = ibase_num_fields($rs);
for ($i=0; $i < $coln; $i++) {
    $col_info = ibase_field_info($rs, $i); 
    echo "name: ".$col_info['name']."\n"; 
    echo "alias: ".$col_info['alias']."\n"; 
    echo "relation: ".$col_info['relation']."\n"; 
    echo "length: ".$col_info['length']."\n"; 
    echo "type: ".$col_info['type']."\n"; 
    }

<?php
       $dbh = ibase_connect ($host, $username, $password);
       $stmt = 'SELECT * FROM tblname';
       $sth = ibase_query ($dbh, $stmt);

       if (ibase_num_fields($sth) > 0) {
       while ($row = ibase_fetch_object ($sth)) {
       print $row->email . "\n";
       }
       } else {
       die ("No Results were found for your query");
       }

       ibase_close ($dbh);
       ?>

ibase_pconnect

(PHP 3>= 3.0.6, PHP 4 )

ibase_pconnect -- Creates an persistent connection to an InterBase database

Description

int ibase_pconnect ( string database [, string username [, string password [, string charset [, int buffers [, int dialect [, string role]]]]]])

ibase_pconnect() acts very much like ibase_connect() with two major differences. First, when connecting, the function will first try to find a (persistent) link that's already opened with the same parameters. If one is found, an identifier for it will be returned instead of opening a new connection. Second, the connection to the InterBase server will not be closed when the execution of the script ends. Instead, the link will remain open for future use (ibase_close() will not close links established by ibase_pconnect()). This type of link is therefore called 'persistent'.

Poznámka: buffers was added in PHP4-RC2.

Poznámka: dialect was added in PHP4-RC2. It is functional only with InterBase 6 and versions higher than that.

Poznámka: role was added in PHP4-RC2. It is functional only with InterBase 5 and versions higher than that.

Sets the format of timestamp, date or time type columns returned from queries. Internally, the columns are formatted by c-function strftime(), so refer to it's documentation regarding to the format of the string. columntype is one of the constants IBASE_TIMESTAMP, IBASE_DATE and IBASE_TIME. If omitted, defaults to IBASE_TIMESTAMP for backwards compatibility.

<?php
       // InterBase 6 TIME-type columns will be returned in
       // the form '05 hours 37 minutes'. 
       ibase_timefmt("%H hours %M minutes", IBASE_TIME);
       ?>

You can also set defaults for these formats with PHP configuration directives ibase.timestampformat, ibase.dateformat and ibase.timeformat.

Poznámka: columntype was added in PHP 4.0. It has any meaning only with InterBase version 6 and higher.

Poznámka: A backwards incompatible change happened in PHP 4.0 when PHP configuration directive ibase.timeformat was renamed to ibase.timestampformat and directives ibase.dateformat and ibase.timeformat were added, so that the names would match better their functionality.

ibase_trans

(PHP 3>= 3.0.7, PHP 4 )

ibase_trans -- Begin a transaction

Description

int ibase_trans ( [int trans_args [, int link_identifier]])

Begins a transaction.

XLVI. Ingres II functions

Úvod

These functions allow you to access Ingres II database servers.

Poznámka: If you already used PHP extensions to access other database servers, note that Ingres doesn't allow concurrent queries and/or transaction over one connection, thus you won't find any result or transaction handle in this extension. The result of a query must be treated before sending another query, and a transaction must be commited or rolled back before opening another transaction (which is automaticaly done when sending the first query).

Varování

Požadavky

To compile PHP with Ingres support, you need the Open API library and header files included with Ingres II.

Instalace

In order to have these functions available, you must compile php with Ingres support by using the --with-ingres option. If the II_SYSTEM environment variable isn't correctly set you may have to use --with-ingres=DIR to specify your Ingres installation directory.

When using this extension with Apache, if Apache does not start and complains with "PHP Fatal error: Unable to start ingres_ii module in Unknown on line 0" then make sure the environement variable II_SYSTEM is correctly set. Adding "export II_SYSTEM="/home/ingres/II" in the script that starts Apache, just before launching httpd, should be fine.

Konfigurace běhu

Toto rozšíření nemá definováno žádné konfigurační direktivy.

Typy prostředků

Toto rezšíření nemá definován žádný typ prostředku (resource).

Předdefinované konstanty

Tyto konstanty jsou definovány tímto rozšířením a budou k dispozici pouze tehdy, bylo-li rozšíření zkompilováno společně s PHP nebo dynamicky zavedeno za běhu.

INGRES_ASSOC (integer)
INGRES_NUM (integer)
INGRES_BOTH (integer)

Obsah
ingres_autocommit -- Switch autocommit on or off
ingres_close -- Close an Ingres II database connection
ingres_commit -- Commit a transaction
ingres_connect -- Open a connection to an Ingres II database
ingres_fetch_array -- Fetch a row of result into an array
ingres_fetch_object -- Fetch a row of result into an object.
ingres_fetch_row -- Fetch a row of result into an enumerated array
ingres_field_length -- Get the length of a field
ingres_field_name -- Get the name of a field in a query result.
ingres_field_nullable -- Test if a field is nullable
ingres_field_precision -- Get the precision of a field
ingres_field_scale -- Get the scale of a field
ingres_field_type -- Get the type of a field in a query result
ingres_num_fields -- Get the number of fields returned by the last query
ingres_num_rows -- Get the number of rows affected or returned by the last query
ingres_pconnect -- Open a persistent connection to an Ingres II database
ingres_query -- Send a SQL query to Ingres II
ingres_rollback -- Roll back a transaction

ingres_autocommit

(PHP 4 >= 4.0.2)

ingres_autocommit -- Switch autocommit on or off

resource ingres_connect ( [string database [, string username [, string password]]])

Varování

Returns a Ingres II link resource on success, or FALSE on failure.

ingres_connect() opens a connection with the Ingres database designated by database, which follows the syntax [node_id::]dbname[/svr_class].

If some parameters are missing, ingres_connect() uses the values in php.ini for ingres.default_database, ingres.default_user, and ingres.default_password.

The connection is closed when the script ends or when ingres_close() is called on this link.

All the other ingres functions use the last opened link as a default, so you need to store the returned value only if you use more than one link at a time.

Příklad 1. ingres_connect() example

<?php
    $link = ingres_connect ("mydb", "user", "pass")
        or die ("Could not connect");
    print ("Connected successfully");
    ingres_close ($link);
?>

Příklad 2. ingres_connect() example using default link

<?php
    ingres_connect ("mydb", "user", "pass")
        or die ("Could not connect");
    print ("Connected successfully");
    ingres_close ();
?>

ingres_fetch_array

(PHP 4 >= 4.0.2)

ingres_fetch_array -- Fetch a row of result into an array

Description

array ingres_fetch_array ( [int result_type [, resource link]])

Varování

ingres_fetch_array() Returns an array that corresponds to the fetched row, or FALSE if there are no more rows.

This function is an extended version of ingres_fetch_row(). In addition to storing the data in the numeric indices of the result array, it also stores the data in associative indices, using the field names as keys.

If two or more columns of the result have the same field names, the last column will take precedence. To access the other column(s) of the same name, you must use the numeric index of the column or make an alias for the column.

ingres_query(select t1.f1 as foo t2.f1 as bar from t1, t2);
$result = ingres_fetch_array();
$foo = $result["foo"];
$bar = $result["bar"];

result_type can be INGRES_NUM for enumerated array, INGRES_ASSOC for associative array, or INGRES_BOTH (default).

Speed-wise, the function is identical to ingres_fetch_object(), and almost as quick as ingres_fetch_row() (the difference is insignificant).

Příklad 1. ingres_fetch_array() example

<?php ingres_connect ($database, $user, $password); ingres_query ("select * from table"); while ($row = ingres_fetch_array()) { echo $row["user_id"]; # using associative array echo $row["fullname"]; echo $row[1]; # using enumerated array echo $row[2]; } ?>

ingres_fetch_object

(PHP 4 >= 4.0.2)

ingres_fetch_object -- Fetch a row of result into an object.

Description

object ingres_fetch_object ( [int result_type [, resource link]])

Varování

ingres_fetch_object() Returns an object that corresponds to the fetched row, or FALSE if there are no more rows.

This function is similar to ingres_fetch_array(), with one difference - an object is returned, instead of an array. Indirectly, that means that you can only access the data by the field names, and not by their offsets (numbers are illegal property names).

The optional argument result_type is a constant and can take the following values: INGRES_ASSOC, INGRES_NUM, and INGRES_BOTH.

Speed-wise, the function is identical to ingres_fetch_array(), and almost as quick as ingres_fetch_row() (the difference is insignificant).

Příklad 1. ingres_fetch_object() example

<?php ingres_connect ($database, $user, $password); ingres_query ("select * from table"); while ($row = ingres_fetch_object()) { echo $row->user_id; echo $row->fullname; } ?>

ingres_fetch_row

(PHP 4 >= 4.0.2)

ingres_fetch_row -- Fetch a row of result into an enumerated array

Description

array ingres_fetch_row ( [resource link])

Varování

Returns TRUE on success, or FALSE on failure.

ingres_query() sends the given query to the Ingres server. This query must be a valid SQL query (see the Ingres SQL reference guide)

The query becomes part of the currently open transaction. If there is no open transaction, ingres_query() opens a new transaction. To close the transaction, you can either call ingres_commit() to commit the changes made to the database or ingres_rollback() to cancel these changes. When the script ends, any open transaction is rolled back (by calling ingres_rollback()). You can also use ingres_autocommit() before opening a new transaction to have every SQL query immediatly commited.

Some types of SQL queries can't be sent with this function:

close (see ingres_close())
commit (see ingres_commit())
connect (see ingres_connect())
disconnect (see ingres_close())
get dbevent
prepare to commit
rollback (see ingres_rollback())
savepoint
set autocommit (see ingres_autocommit())
all cursor related queries are unsupported

Příklad 1. ingres_query() example

<?php ingres_connect ($database, $user, $password); ingres_query ("select * from table"); while ($row = ingres_fetch_row()) { echo $row[1]; echo $row[2]; } ?>

ingres_rollback

(PHP 4 >= 4.0.2)

ingres_rollback -- Roll back a transaction

Description

bool ingres_rollback ( [resource link])

Varování

ingres_rollback() rolls back the currently open transaction, actually canceling all changes made to the database during the transaction.

This closes the transaction. A new one can be open by sending a query with ingres_query().

XLVII. IRC Gateway Functions

What is ircg?

With ircg you can build powerful, fast and scalable webchat solutions in conjunction with dedicated or public IRC servers.

Platforms

IRCG runs under

AIX
FreeBSD
HP-UX
Irix
Linux
Solaris
Tru64

Requirements

To install and use IRCG you need the following software:

IRCG-Library from Sascha Schumann.
SGI Static Threads Library
thttpd webserver

Installation

A detailed installation instruction can be found here.

Obsah
ircg_channel_mode -- Set channel mode flags for user
ircg_disconnect -- Close connection to server
ircg_fetch_error_msg -- Returns the error from previous ircg operation
ircg_get_username -- Get username for connection
ircg_html_encode -- Encodes HTML preserving output
ircg_ignore_add -- Add a user to your ignore list on a server
ircg_ignore_del -- Remove a user from your ignore list on a server
ircg_is_conn_alive -- Check connection status
ircg_join -- Join a channel on a connected server
ircg_kick -- Kick a user out of a channel on server
ircg_lookup_format_messages -- Select a set of format strings for display of IRC messages
ircg_msg -- Send message to channel or user on server
ircg_nick -- Change nickname on server
ircg_nickname_escape -- Encode special characters in nickname to be IRC-compliant
ircg_nickname_unescape -- Decodes encoded nickname
ircg_notice -- Send a notice to a user on server
ircg_part -- Leave a channel on server
ircg_pconnect -- Connect to an IRC server
ircg_register_format_messages -- Register a set of format strings for display of IRC messages
ircg_set_current -- Set current connection for output
ircg_set_file -- Set logfile for connection
ircg_set_on_die -- Set hostaction to be execute when connection dies
ircg_topic -- Set topic for channel on server
ircg_whois -- Query user information for nick on server

ircg_channel_mode

(PHP 4 >= 4.0.5)

ircg_channel_mode -- Set channel mode flags for user

Description

boolean ircg_channel_mode ( resource connection, string channel, string mode_spec, string nick)

Set channel mode flags for channel on server connected to by connection. Mode flags are passed in mode_spec and are applied to the user specified by nick.

Mode flags are set or cleared by specifind a mode character and prepending it with a plus or minus character respectively. E.g. operator mode is granted by '+o' and revoked by '-o' passed as mode_spec.

ircg_disconnect

(PHP 4 >= 4.0.4)

ircg_disconnect -- Close connection to server

Description

boolean ircg_disconnect ( resource connection, string reason)

ircg_disconnect() will close a connection to a server previously established with ircg-pconnect().

ircg_fetch_error_msg

(PHP 4 >= 4.1.0)

ircg_fetch_error_msg -- Returns the error from previous ircg operation

Description

array ircg_fetch_error_msg ( resource connection)

ircg_fetch_error_msg() returns the error from the last called ircg function.

Poznámka: Errorcode is stored in first array element, errortext in second.

ircg_msg() will send the message to a channel or user on the server connected to by connection. A recipient starting with # or & will send the message to a channel, anything else will be interpreted as a username.

Setting the optional parameter suppress to a TRUE value will suppress output of your message to your own connection.

ircg_nick

(PHP 4 >= 4.0.5)

ircg_nick -- Change nickname on server

Description

boolean ircg_nick ( resource connection, string nick)

resource ircg_pconnect ( string username [, string server_ip [, int server_port [, string msg_format [, array ctcp_messages [, array user_settings]]]]])

ircg_pconnect() will try to establish a connection to an IRC server and return a connection resource handle for further use.

The only mandatory parameter is username, this will set your initial nickname on the server. server_ip and server_port are optional and default to 127.0.0.1 and 6667.

Poznámka: For now parameter server_ip will not do any hostname lookups and will only accept IP addresses in numerical form.

Currently ircg_pconnect() always returns a valid handle, even if the connection failed.

You can customize the output of IRC messages and events by selection a format string set previously created with ircg_register_format_messages() by specifing the sets name in msg_format.

ctcp_messages

user_settings

ircg_register_format_messages

(PHP 4 >= 4.0.5)

ircg_register_format_messages -- Register a set of format strings for display of IRC messages

Description

boolean ircg_register_format_messages ( string name, array messages)

With ircg_register_format_messages() you can customize the way your IRC output looks like. You can even register different format string sets and switch between them on the fly with ircg_lookup_format_messages().

Plain channel message
Private message received
Private message sent
Some user leaves channel
Some user enters channel
Some user was kicked from the channel
Topic has been changed
Error
Fatal error
Join list end(?)
Self part(?)
Some user changes his nick
Some user quits his connection
Mass join begin
Mass join element
Mass join end
Whois user
Whois server
Whois idle
Whois channel
Whois end
Voice status change on user
Operator status change on user
Banlist
Banlist end

%f - from
%t - to
%c - channel
%r - plain message
%m - encoded message
%j - js encoded message

1 - mod encode
2 - nickname decode

XLVIII. Java

There are two possible ways to bridge PHP and Java: you can either integrate PHP into a Java Servlet environment, which is the more stable and efficient solution, or integrate Java support into PHP. The former is provided by a SAPI module that interfaces with the Servlet server, the latter by the Java extension.

PHP 4 ext/java provides a simple and effective means for creating and invoking methods on Java objects from PHP. The JVM is created using JNI, and everything runs in-process. Build instructions for ext/java can be found in php4/ext/java/README.

Příklad 1. Java Example

<?php // get instance of Java class java.lang.System in PHP $system = new Java('java.lang.System'); // demonstrate property access print 'Java version='.$system->getProperty('java.version').' <br>'; print 'Java vendor=' .$system->getProperty('java.vendor').' <br>'; print 'OS='.$system->getProperty('os.name').' '. $system->getProperty('os.version').' on '. $system->getProperty('os.arch').' <br>'; // java.util.Date example $formatter = new Java('java.text.SimpleDateFormat', "EEEE, MMMM dd, yyyy 'at' h:mm:ss a zzzz"); print $formatter->format(new Java('java.util.Date')); ?>

Příklad 2. AWT Example

<?php // This example is only intented to be run as a CGI. $frame = new Java('java.awt.Frame', 'PHP'); $button = new Java('java.awt.Button', 'Hello Java World!'); $frame->add('North', $button); $frame->validate(); $frame->pack(); $frame->visible = True; $thread = new Java('java.lang.Thread'); $thread->sleep(10000); $frame->dispose(); ?>
Notes:

new Java() will create an instance of a class if a suitable constructor is available. If no parameters are passed and the default constructor is useful as it provides access to classes like java.lang.System which expose most of their functionallity through static methods.
Accessing a member of an instance will first look for bean properties then public fields. In other words, print $date.time will first attempt to be resolved as $date.getTime(), then as $date.time.
Both static and instance members can be accessed on an object with the same syntax. Furthermore, if the java object is of type java.lang.Class, then static members of the class (fields and methods) can be accessed.
Exceptions raised result in PHP warnings, and NULL results. The warnings may be eliminated by prefixing the method call with an "@" sign. The following APIs may be used to retrieve and reset the last error:
- java_last_exception_get()
- java_last_exception_clear()
Overload resolution is in general a hard problem given the differences in types between the two languages. The PHP Java extension employs a simple, but fairly effective, metric for determining which overload is the best match.

Additionally, method names in PHP are not case sensitive, potentially increasing the number of overloads to select from.

Once a method is selected, the parameters are cooerced if necessary, possibly with a loss of data (example: double precision floating point numbers will be converted to boolean).
In the tradition of PHP, arrays and hashtables may pretty much be used interchangably. Note that hashtables in PHP may only be indexed by integers or strings; and that arrays of primitive types in Java can not be sparse. Also note that these constructs are passed by value, so may be expensive in terms of memory and time.

sapi/servlet builds upon the mechanism defined by ext/java to enable the entire PHP processor to be run as a servlet. The primary advanatage of this from a PHP perspective is that web servers which support servlets typically take great care in pooling and reusing JVMs. Build instructions for the Servlet SAPI module can be found in php4/sapi/README. Notes:

While this code is intended to be able to run on any servlet engine, it has only been tested on Apache's Jakarta/tomcat to date. Bug reports, success stories and/or patches required to get this code to run on other engines would be appreciated.
PHP has a habit of changing the working directory. sapi/servlet will eventually change it back, but while PHP is running the servlet engine may not be able to load any classes from the CLASSPATH which are specified using a relative directory syntax, or find the work directory used for administration and JSP compilation tasks.

Obsah
java_last_exception_clear -- Clear last Java exception
java_last_exception_get -- Get last Java exception

java_last_exception_clear

(PHP 4 >= 4.0.2)

java_last_exception_clear -- Clear last Java exception

Description

void java_last_exception_clear ( void)

java_last_exception_get

(PHP 4 >= 4.0.2)

java_last_exception_get -- Get last Java exception

Description

exception java_last_exception_get ( void)

The following example demonstrates the usage of Java's exception handler from within PHP:

Příklad 1. Java exception handler

<?php $stack = new Java('java.util.Stack'); $stack->push(1); // This should succeed $result = $stack->pop(); $ex = java_last_exception_get(); if (!$ex) print "$result\n"; // This should fail (error suppressed by @) $result = @$stack->pop(); $ex = java_last_exception_get(); if ($ex) print $ex->toString(); // Clear last exception java_last_exception_clear(); ?>

XLIX. LDAP functions

Introduction to LDAP

LDAP is the Lightweight Directory Access Protocol, and is a protocol used to access "Directory Servers". The Directory is a special kind of database that holds information in a tree structure.

The concept is similar to your hard disk directory structure, except that in this context, the root directory is "The world" and the first level subdirectories are "countries". Lower levels of the directory structure contain entries for companies, organisations or places, while yet lower still we find directory entries for people, and perhaps equipment or documents.

To refer to a file in a subdirectory on your hard disk, you might use something like

/usr/local/myapp/docs

The forwards slash marks each division in the reference, and the sequence is read from left to right.

The equivalent to the fully qualified file reference in LDAP is the "distinguished name", referred to simply as "dn". An example dn might be.

cn=John Smith,ou=Accounts,o=My Company,c=US

The comma marks each division in the reference, and the sequence is read from right to left. You would read this dn as ..

    country = US
    organization = My Company
    organizationalUnit = Accounts
    commonName = John Smith

In the same way as there are no hard rules about how you organise the directory structure of a hard disk, a directory server manager can set up any structure that is meaningful for the purpose. However, there are some conventions that are used. The message is that you can not write code to access a directory server unless you know something about its structure, any more than you can use a database without some knowledge of what is available.

Complete code example

Retrieve information for all entries where the surname starts with "S" from a directory server, displaying an extract with name and email address.

Příklad 1. LDAP search example

<?php
// basic sequence with LDAP is connect, bind, search, interpret search
// result, close connection

echo "<h3>LDAP query test</h3>";
echo "Connecting ...";
$ds=ldap_connect("localhost");  // must be a valid LDAP server!
echo "connect result is ".$ds."<p>";

if ($ds) { 
    echo "Binding ..."; 
    $r=ldap_bind($ds);     // this is an "anonymous" bind, typically
                           // read-only access
    echo "Bind result is ".$r."<p>";

    echo "Searching for (sn=S*) ...";
    // Search surname entry
    $sr=ldap_search($ds,"o=My Company, c=US", "sn=S*");  
    echo "Search result is ".$sr."<p>";

    echo "Number of entires returned is ".ldap_count_entries($ds,$sr)."<p>";

    echo "Getting entries ...<p>";
    $info = ldap_get_entries($ds, $sr);
    echo "Data for ".$info["count"]." items returned:<p>";

    for ($i=0; $i<$info["count"]; $i++) {
        echo "dn is: ". $info[$i]["dn"] ."<br>";
        echo "first cn entry is: ". $info[$i]["cn"][0] ."<br>";
        echo "first email entry is: ". $info[$i]["mail"][0] ."<p>";
    }

    echo "Closing connection";
    ldap_close($ds);

} else {
    echo "<h4>Unable to connect to LDAP server</h4>";
}
?>

Using the PHP LDAP calls

You will need to get and compile LDAP client libraries from either the University of Michigan ldap-3.3 package or the Netscape Directory SDK 3.0. You will also need to recompile PHP with LDAP support enabled before PHP's LDAP calls will work.

Before you can use the LDAP calls you will need to know ..

The name or address of the directory server you will use
The "base dn" of the server (the part of the world directory that is held on this server, which could be "o=My Company,c=US")
Whether you need a password to access the server (many servers will provide read access for an "anonymous bind" but require a password for anything else)

The typical sequence of LDAP calls you will make in an application will follow this pattern:

  ldap_connect()    // establish connection to server
     |
  ldap_bind()       // anonymous or authenticated "login"
     |
  do something like search or update the directory
  and display the results
     |
  ldap_close()      // "logout"

More Information

Lots of information about LDAP can be found at

The Netscape SDK contains a helpful Programmer's Guide in .html format.

Obsah
ldap_8859_to_t61 -- Translate 8859 characters to t61 characters
ldap_add -- Add entries to LDAP directory
ldap_bind -- Bind to LDAP directory
ldap_close -- Close link to LDAP server
ldap_compare -- Compare value of attribute found in entry specified with DN
ldap_connect -- Connect to an LDAP server
ldap_count_entries -- Count the number of entries in a search
ldap_delete -- Delete an entry from a directory
ldap_dn2ufn -- Convert DN to User Friendly Naming format
ldap_err2str -- Convert LDAP error number into string error message
ldap_errno -- Return the LDAP error number of the last LDAP command
ldap_error -- Return the LDAP error message of the last LDAP command
ldap_explode_dn -- Splits DN into its component parts
ldap_first_attribute -- Return first attribute
ldap_first_entry -- Return first result id
ldap_first_reference -- Return first reference
ldap_free_result -- Free result memory
ldap_get_attributes -- Get attributes from a search result entry
ldap_get_dn -- Get the DN of a result entry
ldap_get_entries -- Get all result entries
ldap_get_option -- Get the current value for given option
ldap_get_values_len -- Get all binary values from a result entry
ldap_get_values -- Get all values from a result entry
ldap_list -- Single-level search
ldap_mod_add -- Add attribute values to current attributes
ldap_mod_del -- Delete attribute values from current attributes
ldap_mod_replace -- Replace attribute values with new ones
ldap_modify -- Modify an LDAP entry
ldap_next_attribute -- Get the next attribute in result
ldap_next_entry -- Get next result entry
ldap_next_reference -- Get next reference
ldap_parse_reference -- Extract information from reference entry
ldap_parse_result -- Extract information from result
ldap_read -- Read an entry
ldap_rename -- Modify the name of an entry
ldap_search -- Search LDAP tree
ldap_set_option -- Set the value of the given option
ldap_set_rebind_proc -- Set a callback function to do re-binds on referral chasing.
ldap_sort -- Sort LDAP result entries
ldap_start_tls -- Start TLS
ldap_t61_to_8859 -- Translate t61 characters to 8859 characters
ldap_unbind -- Unbind from LDAP directory

ldap_8859_to_t61

(PHP 4 >= 4.0.2)

ldap_8859_to_t61 -- Translate 8859 characters to t61 characters

Description

string ldap_8859_to_t61 ( string value)

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

ldap_add

(PHP 3, PHP 4 )

ldap_add -- Add entries to LDAP directory

Description

bool ldap_add ( resource link_identifier, string dn, array entry)

Vrací TRUE při úspěchu, FALSE při selhání.

The ldap_add() function is used to add entries in the LDAP directory. The DN of the entry to be added is specified by dn. Array entry specifies the information about the entry. The values in the entries are indexed by individual attributes. In case of multiple values for an attribute, they are indexed using integers starting with 0.

    entry["attribute1"] = value
    entry["attribute2"][0] = value1
    entry["attribute2"][1] = value2

Příklad 1. Complete example with authenticated bind

<?php
$ds=ldap_connect("localhost");  // assuming the LDAP server is on this host

if ($ds) {
    // bind with appropriate dn to give update access
    $r=ldap_bind($ds,"cn=root, o=My Company, c=US", "secret");

    // prepare data
    $info["cn"]="John Jones";
    $info["sn"]="Jones";
    $info["mail"]="jonj@here.and.now";
    $info["objectclass"]="person";

    // add data to directory
    $r=ldap_add($ds, "cn=John Jones, o=My Company, c=US", $info);

    ldap_close($ds);
} else {
    echo "Unable to connect to LDAP server"; 
}
?>

ldap_bind

(PHP 3, PHP 4 )

ldap_bind -- Bind to LDAP directory

Description

bool ldap_bind ( resource link_identifier [, string bind_rdn [, string bind_password]])

Binds to the LDAP directory with specified RDN and password. Vrací TRUE při úspěchu, FALSE při selhání.

ldap_bind() does a bind operation on the directory. bind_rdn and bind_password are optional. If not specified, anonymous bind is attempted.

ldap_close

(PHP 3, PHP 4 )

ldap_close -- Close link to LDAP server

Description

bool ldap_close ( resource link_identifier)

Vrací TRUE při úspěchu, FALSE při selhání.

ldap_close() closes the link to the LDAP server that's associated with the specified link_identifier.

This call is internally identical to ldap_unbind(). The LDAP API uses the call ldap_unbind(), so perhaps you should use this in preference to ldap_close().

Poznámka: This function is an alias of ldap_unbind().

ldap_compare

(PHP 4 >= 4.0.2)

ldap_compare -- Compare value of attribute found in entry specified with DN

Description

bool ldap_compare ( resource link_identifier, string dn, string attribute, string value)

Returns TRUE if value matches otherwise returns FALSE. Returns -1 on error.

ldap_compare() is used to compare value of attribute to value of same attribute in LDAP directory entry specified with dn.

The following example demonstrates how to check whether or not given password matches the one defined in DN specified entry.

Příklad 1. Complete example of password check

<?php

$ds=ldap_connect("localhost");  // assuming the LDAP server is on this host
      
if ($ds) {

    // bind 
    if(ldap_bind($ds)) {

        // prepare data
        $dn = "cn=Matti Meikku, ou=My Unit, o=My Company, c=FI";
        $value = "secretpassword";
        $attr = "password"; 

        // compare value
        $r=ldap_compare($ds, $dn, $attr, $value);

        if ($r === -1) {
            echo "Error: ".ldap_error($ds);
        } elseif ($r === TRUE) {
            echo "Password correct.";
        } elseif ($r === FALSE) {
            echo "Wrong guess! Password incorrect.";
        }

    } else {
        echo "Unable to bind to LDAP server.";
    }          

    ldap_close($ds);

} else {
    echo "Unable to connect to LDAP server.";
}
?>

Varování

ldap_compare() can NOT be used to compare BINARY values!

Poznámka: This function was added in 4.0.2.

ldap_connect

(PHP 3, PHP 4 )

ldap_connect -- Connect to an LDAP server

Description

resource ldap_connect ( [string hostname [, int port]])

Returns a positive LDAP link identifier on success, or FALSE on error.

ldap_connect() establishes a connection to a LDAP server on a specified hostname and port. Both the arguments are optional. If no arguments are specified then the link identifier of the already opened link will be returned. If only hostname is specified, then the port defaults to 389.

If you are using OpenLDAP 2.x.x you can specify a URL instead of the hostname. To use LDAP with SSL, compile OpenLDAP 2.x.x with SSL support, configure PHP with SSL, and use ldaps://hostname/ as host parameter. The port parameter is not used when using URLs.

Poznámka: URL and SSL support were added in 4.0.4.

(PHP 3>= 3.0.13, PHP 4 )

ldap_err2str -- Convert LDAP error number into string error message

bool ldap_free_result ( resource result_identifier)

Vrací TRUE při úspěchu, FALSE při selhání.

ldap_free_result() frees up the memory allocated internally to store the result and pointed by the result_identifier. All result memory will be automatically freed when the script terminates.

Typically all the memory allocated for the ldap result gets freed at the end of the script. In case the script is making successive searches which return large result sets, ldap_free_result() could be called to keep the runtime memory usage by the script low.

ldap_get_attributes

(PHP 3, PHP 4 )

ldap_get_attributes -- Get attributes from a search result entry

Description

array ldap_get_attributes ( resource link_identifier, resource result_entry_identifier)

Returns a complete entry information in a multi-dimensional array on success and FALSE on error.

ldap_get_attributes() function is used to simplify reading the attributes and values from an entry in the search result. The return value is a multi-dimensional array of attributes and values.

Having located a specific entry in the directory, you can find out what information is held for that entry by using this call. You would use this call for an application which "browses" directory entries and/or where you do not know the structure of the directory entries. In many applications you will be searching for a specific attribute such as an email address or a surname, and won't care what other data is held.

return_value["count"] = number of attributes in the entry
return_value[0] = first attribute
return_value[n] = nth attribute

return_value["attribute"]["count"] = number of values for attribute
return_value["attribute"][0] = first value of the attribute
return_value["attribute"][i] = (i+1)th value of the attribute

Příklad 1. Show the list of attributes held for a particular directory entry

// $ds is the link identifier for the directory

// $sr is a valid search result from a prior call to
// one of the ldap directory search calls

$entry = ldap_first_entry($ds, $sr);

$attrs = ldap_get_attributes($ds, $entry);

echo $attrs["count"]." attributes held for this entry:<p>";

for ($i=0; $i<$attrs["count"]; $i++)
    echo $attrs[$i]."<br>";

ldap_get_dn

(PHP 3, PHP 4 )

ldap_get_dn -- Get the DN of a result entry

Description

ldap_get_values() function is used to read all the values of the attribute in the entry in the result. entry is specified by the result_entry_identifier. The number of values can be found by indexing "count" in the resultant array. Individual values are accessed by integer index in the array. The first index is 0.

This call needs a result_entry_identifier, so needs to be preceded by one of the ldap search calls and one of the calls to get an individual entry.

You application will either be hard coded to look for certain attributes (such as "surname" or "mail") or you will have to use the ldap_get_attributes() call to work out what attributes exist for a given entry.

LDAP allows more than one entry for an attribute, so it can, for example, store a number of email addresses for one person's directory entry all labeled with the attribute "mail"

return_value["count"] = number of values for attribute
return_value[0] = first value of attribute
return_value[i] = ith value of attribute

Příklad 1. List all values of the "mail" attribute for a directory entry

// $ds is a valid link identifier for a directory server

// $sr is a valid search result from a prior call to
//     one of the ldap directory search calls

// $entry is a valid entry identifier from a prior call to
//        one of the calls that returns a directory entry

$values = ldap_get_values($ds, $entry,"mail");

echo $values["count"]." email addresses for this entry.<p>";

for ($i=0; $i < $values["count"]; $i++)
    echo $values[$i]."<br>";

ldap_list

(PHP 3, PHP 4 )

ldap_list -- Single-level search

Description

resource ldap_list ( resource link_identifier, string base_dn, string filter [, array attributes [, int attrsonly [, int sizelimit [, int timelimit [, int deref]]]]])

Returns a search result identifier or FALSE on error.

ldap_list() performs the search for a specified filter on the directory with the scope LDAP_SCOPE_ONELEVEL.

LDAP_SCOPE_ONELEVEL means that the search should only return information that is at the level immediately below the base_dn given in the call. (Equivalent to typing "ls" and getting a list of files and folders in the current working directory.)

This call takes 5 optional parameters. See ldap_search() notes.

Poznámka: These optional parameters were added in 4.0.2: attrsonly, sizelimit, timelimit, deref.

Příklad 1. Produce a list of all organizational units of an organization

// $ds is a valid link identifier for a directory server

$basedn = "o=My Company, c=US";
$justthese = array("ou");

$sr=ldap_list($ds, $basedn, "ou=*", $justthese);

$info = ldap_get_entries($ds, $sr);

for ($i=0; $i<$info["count"]; $i++)
    echo $info[$i]["ou"][0] ;

Poznámka: From 4.0.5 on it's also possible to do parallel searches. See ldap_search() for details.

An empty filter is not allowed. If you want to retrieve absolutely all information for this entry, use a filter of "objectClass=*". If you know which entry types are used on the directory server, you might use an appropriate filter such as "objectClass=inetOrgPerson".

This call takes 5 optional parameters. See ldap_search() notes.

Poznámka: These optional parameters were added in 4.0.2: attrsonly, sizelimit, timelimit, deref.

From 4.0.5 on it's also possible to do parallel searches. See ldap_search() for details.

ldap_rename

(PHP 4 >= 4.0.5)

ldap_rename -- Modify the name of an entry

Description

bool ldap_rename ( resource link_identifier, string dn, string newrdn, string newparent, bool deleteoldrdn)

The entry specified by dn is renamed/moved. The new RDN is specified by newrdn and the new parent/superior entry is specified by newparent. If the parameter deleteoldrdn is TRUE the old RDN value(s) is removed, else the old RDN value(s) is retained as non-distinguished values of the entry. Vrací TRUE při úspěchu, FALSE při selhání.

Poznámka: This function currently only works with LDAPv3. You may have to use ldap_set_option() prior to binding to use LDAPv3. This function is only available when using OpenLDAP 2.x.x OR Netscape Directory SDK x.x, and was added in PHP 4.0.5.

ldap_search

(PHP 3, PHP 4 )

ldap_search -- Search LDAP tree

Description

resource ldap_search ( resource link_identifier, string base_dn, string filter [, array attributes [, int attrsonly [, int sizelimit [, int timelimit [, int deref]]]]])

Returns a search result identifier or FALSE on error.

ldap_search() performs the search for a specified filter on the directory with the scope of LDAP_SCOPE_SUBTREE. This is equivalent to searching the entire directory. base_dn specifies the base DN for the directory.

There is a optional fourth parameter, that can be added to restrict the attributes and values returned by the server to just those required. This is much more efficient than the default action (which is to return all attributes and their associated values). The use of the fourth parameter should therefore be considered good practice.

The fourth parameter is a standard PHP string array of the required attributes, eg array("mail","sn","cn") Note that the "dn" is always returned irrespective of which attributes types are requested.

Note too that some directory server hosts will be configured to return no more than a preset number of entries. If this occurs, the server will indicate that it has only returned a partial results set. This occurs also if the sixth parameter sizelimit has been used to limit the count of fetched entries.

The fifth parameter attrsonly should be set to 1 if only attribute types are wanted. If set to 0 both attributes types and attribute values are fetched which is the default behaviour.

With the sixth parameter sizelimit it is possible to limit the count of entries fetched. Setting this to 0 means no limit. NOTE: This parameter can NOT override server-side preset sizelimit. You can set it lower though.

The seventh parameter timelimit sets the number of seconds how long is spend on the search. Setting this to 0 means no limit. NOTE: This parameter can NOT override server-side preset timelimit. You can set it lower though.

The eigth parameter deref specifies how aliases should be handled during the search. It can be one of the following:

LDAP_DEREF_NEVER - (default) aliases are never dereferenced.
LDAP_DEREF_SEARCHING - aliases should be dereferenced during the search but not when locating the base object of the search.
LDAP_DEREF_FINDING - aliases should be dereferenced when locating the base object but not during the search.
LDAP_DEREF_ALWAYS - aliases should be dereferenced always.

Poznámka: These optional parameters were added in 4.0.2: attrsonly, sizelimit, timelimit, deref.

The search filter can be simple or advanced, using boolean operators in the format described in the LDAP doumentation (see the Netscape Directory SDK for full information on filters).

The example below retrieves the organizational unit, surname, given name and email address for all people in "My Company" where the surname or given name contains the substring $person. This example uses a boolean filter to tell the server to look for information in more than one attribute.

Příklad 1. LDAP search

// $ds is a valid link identifier for a directory server // $person is all or part of a person's name, eg "Jo" $dn = "o=My Company, c=US"; $filter="(|(sn=$person*)(givenname=$person*))"; $justthese = array( "ou", "sn", "givenname", "mail"); $sr=ldap_search($ds, $dn, $filter, $justthese); $info = ldap_get_entries($ds, $sr); print $info["count"]." entries returned<p>";

From 4.0.5 on it's also possible to do parallel searches. To do this you use an array of link identifiers, rather than a single identifier, as the first argument. If you don't want the same base DN and the same filter for all the searches, you can also use an array of base DNs and/or an array of filters. Those arrays must be of the same size as the link identifier array since the first entries of the arrays are used for one search, the second entries are used for another, and so on. When doing parallel searches an array of search result identifiers is returned, except in case of error, then the entry corresponding to the search will be FALSE. This is very much like the value normally returned, except that a result identifier is always returned when a search was made. There are some rare cases where the normal search returns FALSE while the parallel search returns an identifier.

ldap_set_option

(PHP 4 >= 4.0.4)

ldap_set_option -- Set the value of the given option

Description

bool ldap_set_option ( resource link_identifier, int option, mixed newval)

Sets the value of the specified option to be newval. Vrací TRUE při úspěchu, FALSE při selhání. on error.

The parameter option can be one of: LDAP_OPT_DEREF, LDAP_OPT_SIZELIMIT, LDAP_OPT_TIMELIMIT, LDAP_OPT_PROTOCOL_VERSION, LDAP_OPT_ERROR_NUMBER, LDAP_OPT_REFERRALS, LDAP_OPT_RESTART, LDAP_OPT_HOST_NAME, LDAP_OPT_ERROR_STRING, LDAP_OPT_MATCHED_DN, LDAP_OPT_SERVER_CONTROLS, LDAP_OPT_CLIENT_CONTROLS. Here's a brief description, see draft-ietf-ldapext-ldap-c-api-xx.txt for details.

The options LDAP_OPT_DEREF, LDAP_OPT_SIZELIMIT, LDAP_OPT_TIMELIMIT, LDAP_OPT_PROTOCOL_VERSION and LDAP_OPT_ERROR_NUMBER have integer value, LDAP_OPT_REFERRALS and LDAP_OPT_RESTART have boolean value, and the options LDAP_OPT_HOST_NAME, LDAP_OPT_ERROR_STRING and LDAP_OPT_MATCHED_DN have string value. The first example illustrates their use. The options LDAP_OPT_SERVER_CONTROLS and LDAP_OPT_CLIENT_CONTROLS require a list of controls, this means that the value must be an array of controls. A control consists of an oid identifying the control, an optional value, and an optional flag for criticality. In PHP a control is given by an array containing an element with the key oid and string value, and two optional elements. The optional elements are key value with string value and key iscritical with boolean value. iscritical defaults to FALSE if not supplied. See also the second example below.

Poznámka: This function is only available when using OpenLDAP 2.x.x OR Netscape Directory SDK x.x, and was added in PHP 4.0.4.

Popis

int ezmlm_hash ( string addr)

ezmlm_hash() Počítá hash hodnotu, která je potřeba pro uchovávání EZMLM mailing listů v MySQL databázi.

Příklad 1. Výpočet hashe a přihlášení uživatele

$user = "kris@koehntopp.de"; $hash = ezmlm_hash ($user); $query = sprintf ("INSERT INTO sample VALUES (%s, '%s')", $hash, $user); $db->query($query); // použito databázové rozhraní PHPLIB

mail

(PHP 3, PHP 4 )

mail -- send mail

Popis

bool mail ( string to, string subject, string message [, string additional_headers])

mail() automaticky odmailuje vzkaz specifikovaný v message příjemci specifikovanému v to. Přidáním čárky mezi adresami v to můžete specifikovat více příjemců.

Příklad 1. Odeslání mailu.

mail("rasmus@lerdorf.on.ca", "Můj předmět", "Řádek 1\nŘádek 2\nŘádek 3");

Pokud je předán čtvrtý argument, jeho hodnota se vloží na konec hlaviček. Toto se obvykle používá k přidání extra hlaviček. Vícenásobné hlavičky se oddělují zařádkováním.

Příklad 2. Odeslání mailu s extra hlavičkami.

mail("nobody@aol.com", "předmět", $message, "From: webmaster@$SERVER_NAME\nReply-To: webmaster@$SERVER_NAME\nX-Mailer: PHP/" . phpversion());
K vytvoření komplexních emailů můžete také použít poměrně jednoduché techniky pro tvorbu řetězců.

Příklad 3. Odeslání komplexního emailu

/* recipients */ $recipient .= "Mary <mary@u.college.edu>" . ", " ; //všimněte si čárky $recipient .= "Kelly <kelly@u.college.edu> . ", "; $recipient .= "ronabop@php.net"; /* subject */ $subject = "Birthday Reminders for August"; /* message */ $message .= "Následující email obsahuje formátovanou ASCII tabulku\n"; $message .= "Day \t\tMonth \t\tYear\n"; $message .= "3rd \t\tAug \t\t1970\n"; $message .= "17rd\t\tAug \t\t1973\n"; /* můžete přidat signaturu */ $message .= "--\r\n"; //oddělovač signatury $message .= "Birthday reminder copylefted by public domain"; /* dodatečné hlavičky pro chyby, From, cc, bcc, atd */ $headers .= "From: Birthday Reminder <birthday@php.net>\n"; $headers .= "X-Sender: <birthday@php.net>\n"; $headers .= "X-Mailer: PHP\n"; // mailový klient $headers .= "X-Priority: 1\n"; // Urgentní vzkaz! $headers .= "Return-Path: <birthday@php.net>\n"; // Návratová cesta pro chyby /* Pokud chcete poslat HTML email, odkomentujte následující řádek */ // $headers .= "Content-Type: text/html; charset=iso-8859-1\n"; // Mime typ $headers .= "cc:birthdayarchive@php.net\n"; // CC $headers .= "bcc:birthdaycheck@php.net, birthdaygifts@php.net\n"; // BCC /* a teď to odešleme */ mail($recipient, $subject, $message, $headers);

LI. mailparse functions

Varování

Obsah
mailparse_determine_best_xfer_encoding -- Figures out the best way of encoding the content read from the file pointer fp, which must be seek-able
mailparse_msg_create -- Returns a handle that can be used to parse a message
mailparse_msg_extract_part_file -- Extracts/decodes a message section, decoding the transfer encoding
mailparse_msg_extract_part -- Extracts/decodes a message section. If callbackfunc is not specified, the contents will be sent to "stdout"
mailparse_msg_free -- Frees a handle allocated by mailparse_msg_crea
mailparse_msg_get_part_data -- Returns an associative array of info about the message
mailparse_msg_get_part -- Returns a handle on a given section in a mimemessage
mailparse_msg_get_structure -- Returns an array of mime section names in the supplied message
mailparse_msg_parse_file -- Parse file and return a resource representing the structure
mailparse_msg_parse -- Incrementally parse data into buffer
mailparse_rfc822_parse_addresses -- Parse addresses and returns a hash containing that data
mailparse_stream_encode -- Streams data from source file pointer, apply encoding and write to destfp
mailparse_uudecode_all -- Scans the data from fp and extract each embedded uuencoded file. Returns an array listing filename information

LII. Mathematical Functions

Úvod

These math functions will only handle values within the range of the integer and float types on your computer. (this corresponds currently to the C types long resp. double) If you need to handle bigger numbers, take a look at the arbitrary precision math functions.

Předdefinované konstanty

The following values are defined as constants in PHP by the math extension:

Tabulka 1. Math constants

Constant	Value	Description
M_PI	3.14159265358979323846	Pi
M_E	2.7182818284590452354	e
M_LOG2E	1.4426950408889634074	log_2 e
M_LOG10E	0.43429448190325182765	log_10 e
M_LN2	0.69314718055994530942	log_e 2
M_LN10	2.30258509299404568402	log_e 10
M_PI_2	1.57079632679489661923	pi/2
M_PI_4	0.78539816339744830962	pi/4
M_1_PI	0.31830988618379067154	1/pi
M_2_PI	0.63661977236758134308	2/pi
M_SQRTPI	1.77245385090551602729	sqrt(pi) [4.0.2]
M_2_SQRTPI	1.12837916709551257390	2/sqrt(pi)
M_SQRT2	1.41421356237309504880	sqrt(2)
M_SQRT3	1.73205080756887729352	sqrt(3) [4.0.2]
M_SQRT1_2	0.70710678118654752440	1/sqrt(2)
M_LNPI	1.14472988584940017414	log_e(pi) [4.0.2]
M_EULER	0.57721566490153286061	Euler constant [4.0.2]

Only M_PI is available in PHP versions up to and including PHP 4.0.0. All other constants are available starting with PHP 4.0.0. Constants labeled [4.0.2] were added in PHP 4.0.2.

Obsah
abs -- Absolute value
acos -- Arc cosine
acosh -- Inverse hyperbolic cosine
asin -- Arc sine
asinh -- Inverse hyperbolic sine
atan2 -- arc tangent of two variables
atan -- Arc tangent
atanh -- Inverse hyperbolic tangent
base_convert -- Convert a number between arbitrary bases
bindec -- Binary to decimal
ceil -- Round fractions up
cos -- Cosine
cosh -- Hyperbolic cosine
decbin -- Decimal to binary
dechex -- Decimal to hexadecimal
decoct -- Decimal to octal
deg2rad -- Converts the number in degrees to the radian equivalent
exp -- e to the power of ...
expm1 -- Returns exp(number) - 1, computed in a way that accurate even when the value of number is close to zero
floor -- Round fractions down
getrandmax -- Show largest possible random value
hexdec -- Hexadecimal to decimal
hypot -- Returns sqrt( num1*num1 + num2*num2)
is_finite --
is_infinite --
is_nan --
lcg_value -- Combined linear congruential generator
log10 -- Base-10 logarithm
log1p -- Returns log(1 + number), computed in a way that accurate even when the val ue of number is close to zero
log -- Natural logarithm
max -- Find highest value
min -- Find lowest value
mt_getrandmax -- Show largest possible random value
mt_rand -- Generate a better random value
mt_srand -- Seed the better random number generator
number_format -- Format a number with grouped thousands
octdec -- Octal to decimal
pi -- Get value of pi
pow -- Exponential expression
rad2deg -- Converts the radian number to the equivalent number in degrees
rand -- Generate a random value
round -- Rounds a float
sin -- Sine
sinh -- Hyperbolic sine
sqrt -- Square root
srand -- Seed the random number generator
tan -- Tangent
tanh -- Hyperbolic tangent

abs

(PHP 3, PHP 4 )

abs -- Absolute value

Description

mixed abs ( mixed number)

Returns the absolute value of number. If the argument number is of type float, the return type is also float, otherwise it is integer (as float usually has a bigger value range than integer).

Příklad 1. abs() example

$abs = abs(-4.2); // $abs = 4.2; (double/float)
$abs2 = abs(5);   // $abs2 = 5; (integer)
$abs3 = abs(-5);  // $abs3 = 5; (integer)

acos

(PHP 3, PHP 4 )

acos -- Arc cosine

Description

float acos ( float arg)

Returns the arc cosine of arg in radians. acos() is the complementary function of cos(), which means that a==cos(acos(a)) for every value of a that is within acos()' range.

See also acosh(), asin() and atan().

acosh

(PHP 4 >= 4.1.0)

acosh -- Inverse hyperbolic cosine

Description

float acosh ( float arg)

Returns the inverse hyperbolic cosine of arg, i.e. the value whose hyperbolic cosine is arg.

Poznámka: Tato funkce není implementována na platformách Windows.

See also acos(), asinh() and atanh().

asin

(PHP 3, PHP 4 )

asin -- Arc sine

Description

float asin ( float arg)

Returns the arc sine of arg in radians. asin() is the complementary function of sin(), which means that a==sin(asin(a)) for every value of a that is within asin()'s range.

See also asinh(), acos() and atan().

asinh

(PHP 4 >= 4.1.0)

asinh -- Inverse hyperbolic sine

Description

float asinh ( float arg)

Returns the inverse hyperbolic sine of arg, i.e. the value whose hyperbolic sine is arg.

Poznámka: Tato funkce není implementována na platformách Windows.

Poznámka: Tato funkce není implementována na platformách Windows.

See also atan(), asinh() and acosh().

base_convert

(PHP 3>= 3.0.6, PHP 4 )

base_convert -- Convert a number between arbitrary bases

Description

string base_convert ( string number, int frombase, int tobase)

Returns a string containing number represented in base tobase. The base in which number is given is specified in frombase. Both frombase and tobase have to be between 2 and 36, inclusive. Digits in numbers with a base higher than 10 will be represented with the letters a-z, with a meaning 10, b meaning 11 and z meaning 35.

Příklad 1. base_convert()

$binary = base_convert ($hexadecimal, 16, 2);

bindec

(PHP 3, PHP 4 )

bindec -- Binary to decimal

Description

int bindec ( string binary_string)

Returns the decimal equivalent of the binary number represented by the binary_string argument.

bindec() converts a binary number to an integer. The largest number that can be converted is 31 bits of 1's or 2147483647 in decimal.

ceil

(PHP 3, PHP 4 )

ceil -- Round fractions up

Description

float ceil ( float value)

Returns the next highest integer value by rounding up value if necessary. The return value of ceil() is still of type float as the value range of float is usually bigger than that of integer.

Příklad 1. ceil() example

echo ceil(4.3);    // 5
echo ceil(9.999);  // 10

cos

(PHP 3, PHP 4 )

cos -- Cosine

Description

float cos ( float arg)

cos() returns the cosine of the arg parameter. The arg parameter is in radians.

See also acos(), sin() tan() and deg2rad().

cosh

(PHP 4 >= 4.1.0)

cosh -- Hyperbolic cosine

Description

float cosh ( float arg)

float expm1 ( float number)

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

floor

(PHP 3, PHP 4 )

floor -- Round fractions down

Description

float floor ( float value)

Returns the next lowest integer value by rounding down value if necessary. The return value of floor() is still of type float because the value range of float is usually bigger than that of integer.

Příklad 1. floor() example

echo floor(4.3);   // 4
echo floor(9.999); // 9

getrandmax

(PHP 3, PHP 4 )

getrandmax -- Show largest possible random value

float log1p ( float number)

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

log

(PHP 3, PHP 4 )

log -- Natural logarithm

Description

float log ( float arg)

Returns the natural logarithm of arg.

max

(PHP 3, PHP 4 )

max -- Find highest value

Description

mixed max ( mixed arg1, mixed arg2, mixed argn)

max() returns the numerically highest of the parameter values.

If the first parameter is an array, max() returns the highest value in that array. If the first parameter is an integer, string or float, you need at least two parameters and max() returns the biggest of these values. You can compare an unlimited number of values.

If one or more of the values is a float, all the values will be treated as floats, and a float is returned. If none of the values is a float, all of them will be treated as integers, and an integer is returned.

min

(PHP 3, PHP 4 )

min -- Find lowest value

Description

number min ( number arg1, number arg2 [, ...])

number min ( array numbers)

min() returns the numerically lowest of the parameter values.

In the first variant, you need at least two parameters and min() returns the lowest of these values. You can compare an unlimited number of values. If one of the variables is undefined, min() will fail.

In the second variant, min() returns the lowest value in numbers.

If one or more of the values is a float, all the values will be treated as floats, and a float is returned. If none of the values is a float, all of them will be treated as integers, and an integer is returned. Upon failure, min() returns NULL and an error of level E_WARNING is generated.

<?php
$a = 4; 
$b = 9; 
$c = 3;
$arr = array(99, 34, 11);

// You may want to implement your own error checking in 
// case of failure (a variable may not be set)
if (!$min_value = @min($a, $b, $c)) {
    echo "Could not get min value, please try again.";
} else {
    echo "min value is $min_value";
}

print min($arr);  // 11

?>

mt_getrandmax

void mt_srand ( int seed)

Seeds the random number generator with seed.

// seed with microseconds
function make_seed() {
    list($usec, $sec) = explode(' ', microtime());
    return (float) $sec + ((float) $usec * 100000);
}
mt_srand(make_seed());
$randval = mt_rand();

Poznámka: Since PHP 4.2.0 it's no longer necessary to seed the random number generator before using it.

number_format

(PHP 3, PHP 4 )

number_format -- Format a number with grouped thousands

Description

string number_format ( float number [, int decimals [, string dec_point [, string thousands_sep]]])

number_format() returns a formatted version of number. This function accepts either one, two or four parameters (not three):

If only one parameter is given, number will be formatted without decimals, but with a comma (",") between every group of thousands.

If two parameters are given, number will be formatted with decimals decimals with a dot (".") in front, and a comma (",") between every group of thousands.

If all four parameters are given, number will be formatted with decimals decimals, dec_point instead of a dot (".") before the decimals and thousands_sep instead of a comma (",") between every group of thousands.

Poznámka: Only the first character of thousands_sep is used. For example, if you use foo as thousands_sep on the number 1000, number_format() will return 1f000.

Příklad 1. number_format() Example

For instance, French notation usually use two decimals, comma (',') as decimal separator, and space (' ') as thousand separator. This is achieved with this line :

<?php $number = 1234.56; // english notation (default) $english_format_number = number_format($number); // 1,234.56 // French notation $nombre_format_francais = number_format($number, 2, ',', ' '); // 1 234,56 $number = 1234.5678; // english notation without thousands seperator $english_format_number = number_format($number, 2, '.', ''); // 1234.57 ?>

See also: sprintf(), printf() and sscanf().

octdec

(PHP 3, PHP 4 )

octdec -- Octal to decimal

Description

int octdec ( string octal_string)

Returns the decimal equivalent of the octal number represented by the octal_string argument. The largest number that can be converted is 17777777777 or 2147483647 in decimal.

pi

(PHP 3, PHP 4 )

pi -- Get value of pi

Description

float pi ( void)

Returns an approximation of pi. The returned float has a precision based on the precision directive in php.ini, which defaults to 14. Also, you can use the M_PI constant which yields identical results to pi().

echo pi(); // 3.1415926535898
echo M_PI; // 3.1415926535898

pow

(PHP 3, PHP 4 )

pow -- Exponential expression

Description

number pow ( number base, number exp)

Returns base raised to the power of exp. If possible, this function will return an integer.

If the power cannot be computed, a warning will be issued, and pow() will return FALSE.

Příklad 1. Some examples of pow()

<?php

var_dump( pow(2,8) ); // int(256)
echo pow(-1,20); // 1
echo pow(0, 0); // 1

echo pow(-1, 5.5); // error

?>

Varování

In PHP 4.0.6 and earlier pow() always returned a float, and did not issue warnings.

rad2deg

float round ( float val [, int precision])

Returns the rounded value of val to specified precision (number of digits after the decimal point). precision can also be negative or zero (default).

Výstraha

PHP doesn't handle strings like "12,300.2" correctly by default. See converting from strings.

echo round(3.4);         // 3
echo round(3.5);         // 4
echo round(3.6);         // 4
echo round(3.6, 0);      // 4
echo round(1.95583, 2);  // 1.96
echo round(1241757, -3); // 1242000

Poznámka: The precision parameter is only available in PHP 4.

sin

(PHP 3, PHP 4 )

sin -- Sine

Description

float sin ( float arg)

sin() returns the sine of the arg parameter. The arg parameter is in radians.

<?php

// Precision depends on your precision directive
print sin(deg2rad(60));  //  0.866025403 ...
print sin(60);           // -0.304810621 ...

?>

// seed with microseconds
function make_seed() {
    list($usec, $sec) = explode(' ', microtime());
    return (float) $sec + ((float) $usec * 100000);
}
srand(make_seed());
$randval = rand();

Poznámka: Since PHP 4.2.0 it's no longer necessary to seed the random number generator before using it.

tan

(PHP 3, PHP 4 )

tan -- Tangent

Description

float tan ( float arg)

tan() returns the tangent of the arg parameter. The arg parameter is in radians.

See also atan(), sin(), cos() and deg2rad().

tanh

(PHP 4 >= 4.1.0)

tanh -- Hyperbolic tangent

Description

float tanh ( float arg)

Returns the hyperbolic tangent of arg, defined as sinh(arg)/cosh(arg).

See also tan(), atanh(), sin() and cos().

LIII. Multi-Byte String Functions

Introduction

There are many languages in which all characters can be expressed by single byte. Multi-byte character codes are used to express many characters for many languages. mbstring is developed to handle Japanese characters. However, many mbstring functions are able to handle character encoding other than Japanese.

A multi-byte character encoding represents single character with consecutive bytes. Some character encoding has shift(escape) sequences to start/end multi-byte character strings. Therefore, a multi-byte character string may be destroyed when it is divided and/or counted unless multi-byte character encoding safe method is used. This module provides multi-byte character safe string functions and other utility functions such as conversion functions.

Since PHP is basically designed for ISO-8859-1, some multi-byte character encoding does not work well with PHP. Therefore, it is important to set mbstring.internal_encoding to a character encoding that works with PHP.

PHP4 Character Encoding Requirements

Per byte encoding
Single byte characters in range of 00h-7fh which is compatible with ASCII
Multi-byte characters without 00h-7fh

These are examples of internal character encoding that works with PHP and does NOT work with PHP.

Character encodings work with PHP: 
ISO-8859-*, EUC-JP, UTF-8

Character encodings do NOT work with PHP:
JIS, SJIS

Character encoding, that does not work with PHP, may be converted with mbstring's HTTP input/output conversion feature/function.

Poznámka: SJIS should not be used for internal encoding unless the reader is familiar with parser/compiler, character encoding and character encoding issues.

Poznámka: If you use database with PHP, it is recommended that you use the same character encoding for both database and internal encoding for ease of use and better performance.

If you are using PostgreSQL, it supports character encoding that is different from backend character encoding. See the PostgreSQL manual for details.

How to Enable mbstring

mbstring is an extended module. You must enable module with configure script. Refer to the Install section for details.

The following configure options are related to mbstring module.

--enable-mbstring : Enable mbstring functions. This option is required to use mbstring functions.
--enable-mbstr-enc-trans : Enable HTTP input character encoding conversion using mbstring conversion engine. If this feature is enabled, HTTP input character encoding may be converted to mbstring.internal_encoding automatically.

HTTP Input and Output

HTTP input/output character encoding conversion may convert binary data also. Users are supposed to control character encoding conversion if binary data is used for HTTP input/output.

If enctype for HTML form is set to multipart/form-data, mbstring does not convert character encoding in POST data. If it is the case, strings are needed to be converted to internal character encoding.

HTTP Input
There is no way to control HTTP input character conversion from PHP script. To disable HTTP input character conversion, it has to be done in php.ini.
Příklad 1. Disable HTTP input conversion in php.ini

;; Disable HTTP Input conversion mbstring.http_input = pass
When using PHP as an Apache module, it is possible to override PHP ini setting per Virtual Host in httpd.conf or per directory with .htaccess. Refer to the Configuration section and Apache Manual for details.
HTTP Output

There are several ways to enable output character encoding conversion. One is using php.ini, another is using ob_start() with mb_output_handler() as ob_start callback function.

Poznámka: For PHP3-i18n users, mbstring's output conversion differs from PHP3-i18n. Character encoding is converted using output buffer.

Příklad 2. php.ini setting example

;; Enable output character encoding conversion for all PHP pages ;; Enable Output Buffering output_buffering = On ;; Set mb_output_handler to enable output conversion output_handler = mb_output_handler

Příklad 3. Script example

<?php // Enable output character encoding conversion only for this page // Set HTTP output character encoding to SJIS mb_http_output('SJIS'); // Start buffering and specify "mb_output_handler" as // callback function ob_start('mb_output_handler'); ?>

Supported Character Encoding

Currently, the following character encoding is supported by mbstring module. Caracter encoding may be specified for mbstring functions' encoding parameter.

The following character encoding is supported in this PHP extension :

UCS-4, UCS-4BE, UCS-4LE, UCS-2, UCS-2BE, UCS-2LE, UTF-32, UTF-32BE, UTF-32LE, UCS-2LE, UTF-16, UTF-16BE, UTF-16LE, UTF-8, UTF-7, ASCII, EUC-JP, SJIS, eucJP-win, SJIS-win, ISO-2022-JP, JIS, ISO-8859-1, ISO-8859-2, ISO-8859-3, ISO-8859-4, ISO-8859-5, ISO-8859-6, ISO-8859-7, ISO-8859-8, ISO-8859-9, ISO-8859-10, ISO-8859-13, ISO-8859-14, ISO-8859-15, byte2be, byte2le, byte4be, byte4le, BASE64, 7bit, 8bit and UTF7-IMAP.

php.ini entry, which accepts encoding name, accepts "auto" and "pass" also. mbstring functions, which accepts encoding name, and accepts "auto".

If "pass" is set, no character encoding conversion is performed.

If "auto" is set, it is expanded to "ASCII,JIS,UTF-8,EUC-JP,SJIS".

`php.ini` settings

mbstring.internal_encoding defines default internal character encoding.
mbstring.http_input defines default HTTP input character encoding.
mbstring.http_output defines default HTTP output character encoding.
mbstring.detect_order defines default character code detection order. See also mb_detect_order().
mbstring.substitute_character defines character to substitute for invalid character encoding.

Web Browsers are supposed to use the same character encoding when submitting form. However, browsers may not use the same character encoding. See mb_http_input() to detect character encoding used by browsers.

If enctype is set to multipart/form-data in HTML forms, mbstring does not convert character encoding in POST data. The user must convert them in the script, if conversion is needed.

Although, browsers are smart enough to detect character encoding in HTML. charset is better to be set in HTTP header. Change default_charset according to character encoding.

Příklad 4. php.ini setting example

;; Set default internal encoding ;; Note: Make sure to use character encoding works with PHP mbstring.internal_encoding = UTF-8 ; Set internal encoding to UTF-8 ;; Set default HTTP input character encoding ;; Note: Script cannot change http_input setting. mbstring.http_input = pass ; No conversion. mbstring.http_input = auto ; Set HTTP input to auto ; "auto" is expanded to "ASCII,JIS,UTF-8,EUC-JP,SJIS" mbstring.http_input = SJIS ; Set HTTP2 input to SJIS mbstring.http_input = UTF-8,SJIS,EUC-JP ; Specify order ;; Set default HTTP output character encoding mbstring.http_output = pass ; No conversion mbstring.http_output = UTF-8 ; Set HTTP output encoding to UTF-8 ;; Set default character encoding detection order mbstring.detect_order = auto ; Set detect order to auto mbstring.detect_order = ASCII,JIS,UTF-8,SJIS,EUC-JP ; Specify order ;; Set default substitute character mbstring.substitute_character = 12307 ; Specify Unicode value mbstring.substitute_character = none ; Do not print character mbstring.substitute_character = long ; Long Example: U+3000,JIS+7E7E

Příklad 5. php.ini setting for EUC-JP users

;; Disable Output Buffering output_buffering = Off ;; Set HTTP header charset default_charset = EUC-JP ;; Set HTTP input encoding conversion to auto mbstring.http_input = auto ;; Convert HTTP output to EUC-JP mbstring.http_output = EUC-JP ;; Set internal encoding to EUC-JP mbstring.internal_encoding = EUC-JP ;; Do not print invalid characters mbstring.substitute_character = none

Příklad 6. php.ini setting for SJIS users

;; Enable Output Buffering output_buffering = On ;; Set mb_output_handler to enable output conversion output_handler = mb_output_handler ;; Set HTTP header charset default_charset = Shift_JIS ;; Set http input encoding conversion to auto mbstring.http_input = auto ;; Convert to SJIS mbstring.http_output = SJIS ;; Set internal encoding to EUC-JP mbstring.internal_encoding = EUC-JP ;; Do not print invalid characters mbstring.substitute_character = none

Overload of PHP string functions by mbstring functions with multibyte support

Because almost PHP application written for language using single-byte character encoding, there are some difficulties for multibyte string handling including japanese. Almost PHP string functions such as substr() do not support multibyte string.

Multibyte extension (mbstring) has some PHP string functions with multibyte support (ex. substr() supports mb_substr()).

Multibyte extension (mbstring) also supports 'function overloading' to add multibyte string functionality without code modification. Using function overloading, some PHP string functions will be oveloaded multibyte string functions. For example, mb_substr() is called instead of substr() if function overloading is enabled. Function overload makes easy to port application supporting only single-byte encoding for multibyte application.

mbstring.func_overload in php.ini should be set some positive value to use function overloading. The value should specify the category of overloading functions, sbould be set 1 to enable mail function overloading. 2 to enable string functions, 4 to regular expression functions. For example, if is set for 7, mail, strings, regex functions should be overloaded. The list of overloaded functions are shown in below.

Tabulka 1. Functions to be overloaded

value of mbstring.func_overload	original function	overloaded function
1	mail()	mb_send_mail()
2	strlen()	mb_strlen()
2	strpos()	mb_strpos()
2	strrpos()	mb_strrpos()
2	substr()	mb_substr()
4	ereg()	mb_ereg()
4	eregi()	mb_eregi()
4	ereg_replace()	mb_ereg_replace()
4	eregi_replace()	mb_eregi_replace()
4	split()	mb_split()

Basics for Japanese multi-byte character

Most Japanese characters need more than 1 byte per character. In addition, several character encoding schemas are used under a Japanese environment. There are EUC-JP, Shift_JIS(SJIS) and ISO-2022-JP(JIS) character encoding. As Unicode becomes popular, UTF-8 is used also. To develop Web applications for a Japanese environment, it is important to use the character set for the task in hand, whether HTTP input/output, RDBMS and E-mail.

Storage for a character can be up to six bytes
A multi-byte character is usually twice of the width compared to single-byte characters. Wider characters are called "zen-kaku" - meaning full width, narrower characters are called "han-kaku" - meaning half width. "zen-kaku" characters are usually fixed width.
Some character encoding defines shift(escape) sequence for entering/exiting multi-byte character strings.
ISO-2022-JP must be used for SMTP/NNTP.
"i-mode" web site is supposed to use SJIS.

References

Multi-byte character encoding and its related issues are very complex. It is impossible to cover in sufficient detail here. Please refer to the following URLs and other resources for further readings.

Unicode/UTF/UCS/etc

http://www.unicode.org/
Japanese/Korean/Chinese character information

ftp://ftp.ora.com/pub/examples/nutshell/ujip/doc/cjk.inf

Obsah
mb_convert_encoding -- Convert character encoding
mb_convert_kana -- Convert "kana" one from another ("zen-kaku" ,"han-kaku" and more)
mb_convert_variables -- Convert character code in variable(s)
mb_decode_mimeheader -- Decode string in MIME header field
mb_decode_numericentity -- Decode HTML numeric string reference to character
mb_detect_encoding -- Detect character encoding
mb_detect_order -- Set/Get character encoding detection order
mb_encode_mimeheader -- Encode string for MIME header
mb_encode_numericentity -- Encode character to HTML numeric string reference
mb_ereg_match -- Regular expression match for multibyte string
mb_ereg_replace -- Replace regular expression with multibyte support
mb_ereg_search_getpos -- Returns start point for next regular expression match
mb_ereg_search_getregs -- Retrive the result from the last multibyte regular expression match
mb_ereg_search_init -- Setup string and regular expression for multibyte regular expression match
mb_ereg_search_pos -- Return position and length of matched part of multibyte regular expression for predefined multibyte string
mb_ereg_search_regs -- Returns the matched part of multibyte regular expression
mb_ereg_search_setpos -- Set start point of next regular expression match
mb_ereg_search -- Multibyte regular expression match for predefined multibyte string
mb_ereg -- Regular expression match with multibyte support
mb_eregi_replace -- Replace regular expression with multibyte support ignoring case
mb_eregi -- Regular expression match ignoring case with multibyte support
mb_get_info -- Get internal settings of mbstring
mb_http_input -- Detect HTTP input character encoding
mb_http_output -- Set/Get HTTP output character encoding
mb_internal_encoding -- Set/Get internal character encoding
mb_language -- Set/Get current language
mb_output_handler -- Callback function converts character encoding in output buffer
mb_parse_str -- Parse GET/POST/COOKIE data and set global variable
mb_preferred_mime_name -- Get MIME charset string
mb_regex_encoding -- Returns current encoding for multibyte regex as string
mb_send_mail -- Send encoded mail.
mb_split -- Split multibyte string using regular expression
mb_strcut -- Get part of string
mb_strimwidth -- Get truncated string with specified width
mb_strlen -- Get string length
mb_strpos -- Find position of first occurrence of string in a string
mb_strrpos -- Find position of last occurrence of a string in a string
mb_strwidth -- Return width of string
mb_substitute_character -- Set/Get substitution character
mb_substr -- Get part of string

mb_convert_encoding

(PHP 4 >= 4.0.6)

mb_convert_encoding -- Convert character encoding

Description

array mb_detect_order ( [mixed encoding-list])

mb_detect_order() sets automatic character encoding detection order to encoding-list. It returns TRUE for success, FALSE for failure.

encoding-list is array or comma separated list of character encoding. ("auto" is expanded to "ASCII, JIS, UTF-8, EUC-JP, SJIS")

If encoding-list is omitted, it returns current character encoding detection order as array.

This setting affects mb_detect_encoding() and mb_send_mail().

Poznámka: mbstring currently implements following encoding detection filters. If there is a invalid byte sequence for following encoding, encoding detection will fail.

Poznámka: UTF-8, UTF-7, ASCII, EUC-JP,SJIS, eucJP-win, SJIS-win, JIS, ISO-2022-JP

For ISO-8859-*, mbstring always detects as ISO-8859-*.

For UTF-16, UTF-32, UCS2 and UCS4, encoding detection will fail always.
Příklad 1. Useless detect order example
; Always detect as ISO-8859-1
detect_order = ISO-8859-1, UTF-8

; Always detect as UTF-8, since ASCII/UTF-7 values are 
; valid for UTF-8
detect_order = UTF-8, ASCII, UTF-7

Příklad 2. mb_detect_order() examples

/* Set detection order by enumerated list */ mb_detect_order("eucjp-win,sjis-win,UTF-8"); /* Set detection order by array */ $ary[] = "ASCII"; $ary[] = "JIS"; $ary[] = "EUC-JP"; mb_detect_order($ary); /* Display current detection order */ echo implode(", ", mb_detect_order());

mb_encode_mimeheader

(PHP 4 >= 4.0.6)

mb_encode_mimeheader -- Encode string for MIME header

Description

string mb_encode_mimeheader ( string str [, string charset [, string transfer-encoding [, string linefeed]]])

string mb_ereg_replace ( string pattern, string replacement, string string [, array option])

Varování

mb_ereg_replace() scans string for matches to pattern, then replaces the matched text with replacement and returns the result string or FALSE on error. Multibyte character can be used in pattern.

Matching condition can be set by option parameter. If i is specified for this parameter, the case will be ignored. If x is specified, white space will be ignored. If m is specified, match will be executed in multiline mode and line break will be included in '.'. If p is specified, match will be executed in POSIX mode, line break will be considered as normal character. If e is specified, replacement string will be evaluated as PHP expression.

The internal encoding or the character encoding specified in mb_regex_encoding() will be used as character encoding.

Poznámka: This function is supported in PHP 4.2.0 or higher.

mb_ereg_search_getpos

(PHP 4 >= 4.2.0)

mb_ereg_search_getpos -- Returns start point for next regular expression match

Description

array mb_ereg_search_getpos ( void)

Varování

mb_ereg_search_getpos() returns the point to start regular expression match for mb_ereg_search(), mb_ereg_search_pos(), mb_ereg_search_regs(). The position is represented by bytes from the head of string.

The internal encoding or the character encoding specified in mb_regex_encoding() will be used as character encoding.

Poznámka: This function is supported in PHP 4.2.0 or higher.

mb_ereg_search_getregs

(PHP 4 >= 4.2.0)

mb_ereg_search_getregs -- Retrive the result from the last multibyte regular expression match

Description

array mb_ereg_search_getregs ( void)

Varování

mb_ereg_search_getregs() returns an array including the sub-string of matched part by last mb_ereg_search(), mb_ereg_search_pos(), mb_ereg_search_regs(). If there are some maches, the first element will have the matched sub-string, the second element will have the first part grouped with brackets, the third element will have the second part grouped with brackets, and so on. It returns FALSE on error;

The internal encoding or the character encoding specified in mb_regex_encoding() will be used as character encoding.

Poznámka: This function is supported in PHP 4.2.0 or higher.

mb_ereg_search_init

(PHP 4 >= 4.2.0)

mb_ereg_search_init -- Setup string and regular expression for multibyte regular expression match

Description

array mb_ereg_search_init ( string string [, string pattern [, string option]])

Varování

mb_ereg_search_init() sets string and pattern for multibyte regular expression. These values are used for mb_ereg_search(), mb_ereg_search_pos(), mb_ereg_search_regs(). It returns TRUE for success, FALSE for error.

The internal encoding or the character encoding specified in mb_regex_encoding() will be used as character encoding.

Poznámka: This function is supported in PHP 4.2.0 or higher.

mb_ereg_search_pos

(PHP 4 >= 4.2.0)

mb_ereg_search_pos -- Return position and length of matched part of multibyte regular expression for predefined multibyte string

Description

array mb_ereg_search_pos ( [string pattern [, string option]])

Varování

mb_ereg_search_pos() returns an array including position of matched part for multibyte regular expression. The first element of the array will be the beggining of matched part, the second element will be length (bytes) of matched part. It returns FALSE on error.

The string for match is specified by mb_ereg_search_init(). It it is not specified, the previous one will be used.

The internal encoding or the character encoding specified in mb_regex_encoding() will be used as character encoding.

Poznámka: This function is supported in PHP 4.2.0 or higher.

mb_ereg_search_regs

(PHP 4 >= 4.2.0)

mb_ereg_search_regs -- Returns the matched part of multibyte regular expression

Description

array mb_ereg_search_regs ( [string pattern [, string option]])

Varování

mb_ereg_search_regs() executes the multibyte regular expression match, and if there are some matched part, it returns an array including substring of matched part as first element, the first grouped part with brackets as second element, the second grouped part as third element, and so on. It returns FALSE on error.

The internal encoding or the character encoding specified in mb_regex_encoding() will be used as character encoding.

Poznámka: This function is supported in PHP 4.2.0 or higher.

mb_ereg_search_setpos

(PHP 4 >= 4.2.0)

mb_ereg_search_setpos -- Set start point of next regular expression match

Description

array mb_ereg_search_setpos ( void)

Varování

mb_ereg_search_setpos() sets the starting point of match for mb_ereg_search().

The internal encoding or the character encoding specified in mb_regex_encoding() will be used as character encoding.

Poznámka: This function is supported in PHP 4.2.0 or higher.

mb_ereg_search

(PHP 4 >= 4.2.0)

mb_ereg_search -- Multibyte regular expression match for predefined multibyte string

Description

bool mb_ereg_search ( [string pattern [, string option]])

Varování

mb_ereg_search() returns TRUE if the multibyte string matches with the regular expression, FALSE for otherwise. The string for matching is set by mb_ereg_search_init(). If pattern is not specified, the previous one is used.

The internal encoding or the character encoding specified in mb_regex_encoding() will be used as character encoding.

Poznámka: This function is supported in PHP 4.2.0 or higher.

mb_ereg

(PHP 4 >= 4.2.0)

mb_ereg -- Regular expression match with multibyte support

Description

int mb_ereg ( string pattern, string string [, array regs])

Varování

mb_ereg() executes the regular expression match with multibyte support, and returns 1 if matches are found. If the optional third parameter was specified, the function returns the byte length of matched part, and therarray regs will contain the substring of matched string. The functions returns 1 if it matches with the empty string. It no matche found or error happend, FALSE will be returned.

The internal encoding or the character encoding specified in mb_regex_encoding() will be used as character encoding.

Poznámka: This function is supported in PHP 4.2.0 or higher.

mb_eregi_replace

(PHP 4 >= 4.2.0)

mb_eregi_replace -- Replace regular expression with multibyte support ignoring case

Description

string mb_eregi_replace ( string pattern, string replace, string string)

Varování

The internal encoding or the character encoding specified in mb_regex_encoding() will be used as character encoding.

Poznámka: This function is supported in PHP 4.2.0 or higher.

mb_eregi

(PHP 4 >= 4.2.0)

mb_eregi -- Regular expression match ignoring case with multibyte support

Description

int mb_eregi ( string pattern, string string [, array regs])

Varování

mb_eregi() executes the regular expression match with multibyte support, and returns 1 if matches are found. This function ignore case. If the optional third parameter was specified, the function returns the byte length of matched part, and therarray regs will contain the substring of matched string. The functions returns 1 if it matches with the empty string. It no matche found or error happend, FALSE will be returned.

The internal encoding or the character encoding specified in mb_regex_encoding() will be used as character encoding.

Poznámka: This function is supported in PHP 4.2.0 or higher.

mb_get_info

(PHP 4 >= 4.2.0)

mb_get_info -- Get internal settings of mbstring

Description

string mb_get_info ( [string type])

Varování

mb_get_info() returns internal setting parameter of mbstring.

If type isn't specified or is specified to "all", an array having the elements "internal_encoding", "http_output", "http_input", "func_overload" will be returned.

If type is specified for "http_output", "http_input", "internal_encoding", "func_overload", the specified setting parameter will be returned.

mb_http_input

(PHP 4 >= 4.0.6)

mb_http_input -- Detect HTTP input character encoding

Description

string mb_http_input ( [string type])

mb_http_input() returns result of HTTP input character encoding detection.

type: Input string specifies input type. "G" for GET, "P" for POST, "C" for COOKIE. If type is omitted, it returns last input type processed.

Return Value: Character encoding name. If mb_http_input() does not process specified HTTP input, it returns FALSE.

mb_http_output

(PHP 4 >= 4.0.6)

mb_http_output -- Set/Get HTTP output character encoding

Description

string mb_http_output ( [string encoding])

If encoding is set, mb_http_output() sets HTTP output character encoding to encoding. Output after this function is converted to encoding. mb_http_output() returns TRUE for success and FALSE for failure.

If encoding is omitted, mb_http_output() returns current HTTP output character encoding.

mb_internal_encoding

(PHP 4 >= 4.0.6)

mb_internal_encoding -- Set/Get internal character encoding

Description

string mb_internal_encoding ( [string encoding])

mb_internal_encoding() sets internal character encoding to encoding If parameter is omitted, it returns current internal encoding.

encoding is used for HTTP input character encoding conversion, HTTP output character encoding conversion and default character encoding for string functions defined by mbstring module.

encoding: Character encoding name

Return Value: If encoding is set,mb_internal_encoding() returns TRUE for success, otherwise returns FALSE. If encoding is omitted, it returns current character encoding name.

Příklad 1. mb_internal_encoding() example

/* Set internal character encoding to UTF-8 */ mb_internal_encoding("UTF-8"); /* Display current internal character encoding */ echo mb_internal_encoding();

mb_language

(PHP 4 >= 4.0.6)

mb_language -- Set/Get current language

Description

string mb_language ( [string language])

mb_language() sets language. If language is omitted, it returns current language as string.

language setting is used for encoding e-mail messages. Valid languages are "Japanese", "ja","English","en" and "uni" (UTF-8). mb_send_mail() uses this setting to encode e-mail.

Language and its setting is ISO-2022-JP/Base64 for Japanese, UTF-8/Base64 for uni, ISO-8859-1/quoted printable for English.

Return Value: If language is set and language is valid, it returns TRUE. Otherwise, it returns FALSE. When language is omitted, it returns language name as string. If no language is set previously, it returns FALSE.

mb_output_handler

(PHP 4 >= 4.0.6)

mb_output_handler -- Callback function converts character encoding in output buffer

Description

string mb_output_handler ( string contents, int status)

mb_output_handler() is ob_start() callback function. mb_output_handler() converts characters in output buffer from internal character encoding to HTTP output character encoding.

4.1.0 or later version, this hanlder adds charset HTTP header when following conditions are met:

Does not set Content-Type by header()
Default MIME type begins with text/
http_output setting is other than pass

contents : Output buffer contents

status : Output buffer status

Return Value: String converted

Příklad 1. mb_output_handler() example

mb_http_output("UTF-8"); ob_start("mb_output_handler");

Poznámka: If you want to output some binary data such as image from PHP script, you must set output encoding to "pass" using mb_http_output().

mb_parse_str

(PHP 4 >= 4.0.6)

mb_parse_str -- Parse GET/POST/COOKIE data and set global variable

Description

boolean mb_parse_str ( string encoded_string [, array result])

mb_parse_str() parses GET/POST/COOKIE data and sets global variables. Since PHP does not provide raw POST/COOKIE data, it can only used for GET data for now. It preses URL encoded data, detects encoding, converts coding to internal encoding and set values to result array or global variables.

encoded_string: URL encoded data.

result: Array contains decoded and character encoding converted values.

Return Value: It returns TRUE for success or FALSE for failure.

mb_preferred_mime_name

(PHP 4 >= 4.0.6)

mb_preferred_mime_name -- Get MIME charset string

Description

string mb_preferred_mime_name ( string encoding)

mb_preferred_mime_name() returns MIME charset string for character encoding encoding. It returns charset string.

Příklad 1. mb_preferred_mime_string() example

$outputenc = "sjis-win"; mb_http_output($outputenc); ob_start("mb_output_handler"); header("Content-Type: text/html; charset=" . mb_preferred_mime_name($outputenc));

mb_regex_encoding

(PHP 4 >= 4.2.0)

mb_regex_encoding -- Returns current encoding for multibyte regex as string

Description

string mb_regex_encoding ( [string encoding])

Varování

mb_regex_encoding() returns the character encoding used by multibyte regex functions.

If the optional parameter encoding is specified, it is set to the character encoding for multibyte regex. The default value is the internal character encoding.

Poznámka: This function is supported in PHP 4.2.0 or higher.

mb_send_mail

(PHP 4 >= 4.0.6)

mb_send_mail -- Send encoded mail.

Description

boolean mb_send_mail ( string to, string subject, string message [, string additional_headers [, string additional_parameter]])

mb_send_mail() sends email. Headers and message are converted and encoded according to mb_language() setting. mb_send_mail() is wrapper function of mail(). See mail() for details.

to is mail addresses send to. Multiple recipients can be specified by putting a comma between each address in to. This parameter is not automatically encoded.

subject is subject of mail.

message is mail message.

additional_headers is inserted at the end of the header. This is typically used to add extra headers. Multiple extra headers are separated with a newline ("\n").

additional_parameter is a MTA command line parameter. It is useful when setting the correct Return-Path header when using sendmail.

Vrací TRUE při úspěchu, FALSE při selhání.

mb_split

(PHP 4 >= 4.2.0)

mb_split -- Split multibyte string using regular expression

Description

array mb_split ( string pattern, string string [, int limit])

Varování

mb_split() split multibyte string using regular expression pattern and returns the result as an array.

If optional parameter limit is specified, it will be split in limit elements as maximum.

The internal encoding or the character encoding specified in mb_regex_encoding() will be used as character encoding.

Poznámka: This function is supported in PHP 4.2.0 or higher.

mb_strcut

(PHP 4 >= 4.0.6)

mb_strcut -- Get part of string

Description

string mb_strcut ( string str, int start [, int length [, string encoding]])

mb_strcut() returns the portion of str specified by the start and length parameters.

mb_strcut() performs equivalent operation as mb_substr() with different method. If start position is multi-byte character's second byte or larger, it starts from first byte of multi-byte character.

It subtracts string from str that is shorter than length AND character that is not part of multi-byte string or not being middle of shift sequence.

encoding is character encoding. If it is not set, internal character encoding is used.

mb_strimwidth

(PHP 4 >= 4.0.6)

mb_strimwidth -- Get truncated string with specified width

Description

string mb_strimwidth ( string str, int start, int width, string trimmarker [, string encoding])

mb_strimwidth() truncates string str to specified width. It returns truncated string.

If trimmarker is set, trimmarker is appended to return value.

start is start position offset. Number of characters from the beginning of string. (First character is 0)

trimmarker is string that is added to the end of string when string is truncated.

encoding is character encoding. If it is omitted, internal encoding is used.

Příklad 1. mb_strimwidth() example

$str = mb_strimwidth($str, 0, 40, "..>");

mb_strlen

(PHP 4 >= 4.0.6)

mb_strlen -- Get string length

Description

string mb_strlen ( string str [, string encoding])

mb_strlen() returns number of characters in string str having character encoding encoding. A multi-byte character is counted as 1.

encoding is character encoding for str. If encoding is omitted, internal character encoding is used.

mb_strpos

(PHP 4 >= 4.0.6)

mb_strpos -- Find position of first occurrence of string in a string

Description

int mb_strpos ( string haystack, string needle [, int offset [, string encoding]])

mb_strpos() returns the numeric position of the first occurrence of needle in the haystack string. If needle is not found, it returns FALSE.

mixed mb_substitute_character ( [mixed substrchar])

mb_substitute_character() specifies substitution character when input character encoding is invalid or character code is not exist in output character encoding. Invalid characters may be substituted NULL(no output), string or integer value (Unicode character code value).

This setting affects mb_detect_encoding() and mb_send_mail().

substchar : Specify Unicode value as integer or specify as string as follows

"none" : no output
"long" : Output character code value (Example: U+3000,JIS+7E7E)

Return Value: If substchar is set, it returns TRUE for success, otherwise returns FALSE. If substchar is not set, it returns Unicode value or "none"/"long".

Příklad 1. mb_substitute_character() example

/* Set with Unicode U+3013 (GETA MARK) */ mb_substitute_character(0x3013); /* Set hex format */ mb_substitute_character("long"); /* Display current setting */ echo mb_substitute_character();

mb_substr

(PHP 4 >= 4.0.6)

mb_substr -- Get part of string

Description

string mb_substr ( string str, int start [, int length [, string encoding]])

mb_substr() returns the portion of str specified by the start and length parameters.

mb_substr() performs multi-byte safe substr() operation based on number of characters. Position is counted from the beginning of str. First character's position is 0. Second character position is 1, and so on.

If encoding is omitted, internal encoding is assumed.

encoding is character encoding. If it is omitted, internal character encoding is used.

LIV. MCAL functions

MCAL stands for Modular Calendar Access Library.

Libmcal is a C library for accessing calendars. It's written to be very modular, with pluggable drivers. MCAL is the calendar equivalent of the IMAP module for mailboxes.

With mcal support, a calendar stream can be opened much like the mailbox stream with the IMAP support. Calendars can be local file stores, remote ICAP servers, or other formats that are supported by the mcal library.

Calendar events can be pulled up, queried, and stored. There is also support for calendar triggers (alarms) and recurring events.

With libmcal, central calendar servers can be accessed, removing the need for any specific database or local file programming.

To get these functions to work, you have to compile PHP with --with-mcal. That requires the mcal library to be installed. Grab the latest version from http://mcal.chek.com/ and compile and install it.

The following constants are defined when using the MCAL module. For weekdays :

MCAL_SUNDAY
MCAL_MONDAY
MCAL_TUESDAY
MCAL_WEDNESDAY
MCAL_THURSDAY
MCAL_FRIDAY
MCAL_SATURDAY

For recurrence :

MCAL_RECUR_NONE
MCAL_RECUR_DAILY
MCAL_RECUR_WEEKLY
MCAL_RECUR_MONTHLY_MDAY
MCAL_RECUR_MONTHLY_WDAY
MCAL_RECUR_YEARLY

For months :

MCAL_JANUARY
MCAL_FEBRUARY
MCAL_MARCH
MCAL_APRIL
MCAL_MAY
MCAL_JUNE
MCAL_JULY
MCAL_AUGUST
MCAL_SEPTEMBER
MCAL_OCTOBER
MCAL_NOVEMBER
MCAL_DECEMBER

Most of the functions use an internal event structure that is unique for each stream. This alleviates the need to pass around large objects between functions. There are convenience functions for setting, initializing, and retrieving the event structure values.

Obsah
mcal_append_event -- Store a new event into an MCAL calendar
mcal_close -- Close an MCAL stream
mcal_create_calendar -- Create a new MCAL calendar
mcal_date_compare -- Compares two dates
mcal_date_valid -- Returns TRUE if the given year, month, day is a valid date
mcal_day_of_week -- Returns the day of the week of the given date
mcal_day_of_year -- Returns the day of the year of the given date
mcal_days_in_month -- Returns the number of days in the given month
mcal_delete_calendar -- Delete an MCAL calendar
mcal_delete_event -- Delete an event from an MCAL calendar
mcal_event_add_attribute -- Adds an attribute and a value to the streams global event structure
mcal_event_init -- Initializes a streams global event structure
mcal_event_set_alarm -- Sets the alarm of the streams global event structure
mcal_event_set_category -- Sets the category of the streams global event structure
mcal_event_set_class -- Sets the class of the streams global event structure
mcal_event_set_description -- Sets the description of the streams global event structure
mcal_event_set_end -- Sets the end date and time of the streams global event structure
mcal_event_set_recur_daily -- Sets the recurrence of the streams global event structure
mcal_event_set_recur_monthly_mday -- Sets the recurrence of the streams global event structure
mcal_event_set_recur_monthly_wday -- Sets the recurrence of the streams global event structure
mcal_event_set_recur_none -- Sets the recurrence of the streams global event structure
mcal_event_set_recur_weekly -- Sets the recurrence of the streams global event structure
mcal_event_set_recur_yearly -- Sets the recurrence of the streams global event structure
mcal_event_set_start -- Sets the start date and time of the streams global event structure
mcal_event_set_title -- Sets the title of the streams global event structure
mcal_expunge -- Deletes all events marked for being expunged.
mcal_fetch_current_stream_event -- Returns an object containing the current streams event structure
mcal_fetch_event -- Fetches an event from the calendar stream
mcal_is_leap_year -- Returns if the given year is a leap year or not
mcal_list_alarms -- Return a list of events that has an alarm triggered at the given datetime
mcal_list_events -- Return a list of IDs for a date or a range of dates.
mcal_next_recurrence -- Returns the next recurrence of the event
mcal_open -- Opens up an MCAL connection
mcal_popen -- Opens up a persistent MCAL connection
mcal_rename_calendar -- Rename an MCAL calendar
mcal_reopen -- Reopens an MCAL connection
mcal_snooze -- Turn off an alarm for an event
mcal_store_event -- Modify an existing event in an MCAL calendar
mcal_time_valid -- Returns TRUE if the given year, month, day is a valid time
mcal_week_of_year -- Returns the week number of the given date

mcal_append_event

(PHP 4 )

mcal_append_event -- Store a new event into an MCAL calendar

Description

int mcal_delete_event ( int mcal_stream [, int event_id])

mcal_delete_event() deletes the calendar event specified by the event_id.

Returns TRUE.

mcal_event_add_attribute

(PHP 3>= 3.0.15, PHP 4 )

mcal_event_add_attribute -- Adds an attribute and a value to the streams global event structure

int mcal_event_set_start ( int stream, int year, int month [, int day [, int hour [, int min [, int sec]]]])

mcal_event_set_start() sets the streams global event structure's start date and time to the given values.

Returns TRUE.

mcal_event_set_title

(PHP 3>= 3.0.13, PHP 4 )

mcal_event_set_title -- Sets the title of the streams global event structure

Description

int mcal_event_set_title ( int stream, string title)

mcal_event_set_title() sets the streams global event structure's title to the given string.

Returns TRUE.

mcal_expunge

object mcal_fetch_event ( int mcal_stream, int event_id [, int options])

mcal_fetch_event() fetches an event from the calendar stream specified by id.

Returns an event object consisting of:

int id - ID of that event.
int public - TRUE if the event if public, FALSE if it is private.
string category - Category string of the event.
string title - Title string of the event.
string description - Description string of the event.
int alarm - number of minutes before the event to send an alarm/reminder.
object start - Object containing a datetime entry.
object end - Object containing a datetime entry.
int recur_type - recurrence type
int recur_interval - recurrence interval
datetime recur_enddate - recurrence end date
int recur_data - recurrence data

All datetime entries consist of an object that contains:

int year - year
int month - month
int mday - day of month
int hour - hour
int min - minutes
int sec - seconds
int alarm - minutes before event to send an alarm

The possible values for recur_type are:

0 - Indicates that this event does not recur
1 - This event recurs daily
2 - This event recurs on a weekly basis
3 - This event recurs monthly on a specific day of the month (e.g. the 10th of the month)
4 - This event recurs monthly on a sequenced day of the week (e.g. the 3rd Saturday)
5 - This event recurs on an annual basis

mcal_is_leap_year

(PHP 3>= 3.0.13, PHP 4 )

mcal_is_leap_year -- Returns if the given year is a leap year or not

mcal_week_of_year

(PHP 4 )

mcal_week_of_year -- Returns the week number of the given date

Description

int mcal_week_of_year ( int day, int month, int year)

LV. Mcrypt Encryption Functions

This is an interface to the mcrypt library, which supports a wide variety of block algorithms such as DES, TripleDES, Blowfish (default), 3-WAY, SAFER-SK64, SAFER-SK128, TWOFISH, TEA, RC2 and GOST in CBC, OFB, CFB and ECB cipher modes. Additionally, it supports RC6 and IDEA which are considered "non-free".

Mcrypt can be used to encrypt and decrypt using the above mentioned ciphers. If you linked against libmcrypt-2.2.x, the four important mcrypt commands (mcrypt_cfb(), mcrypt_cbc(), mcrypt_ecb(), and mcrypt_ofb()) can operate in both modes which are named MCRYPT_ENCRYPT and MCRYPT_DECRYPT, respectively.

Příklad 1. Encrypt an input value with TripleDES under 2.2.x in ECB mode

<?php $key = "this is a very secret key"; $input = "Let us meet at 9 o'clock at the secret place."; $encrypted_data = mcrypt_ecb (MCRYPT_3DES, $key, $input, MCRYPT_ENCRYPT); ?>
This example will give you the encrypted data as a string in $encrypted_data.

If you linked against libmcrypt 2.4.x or 2.5.x, these functions are still available, but it is recommended that you use the advanced functions.

Příklad 2. Encrypt an input value with TripleDES under 2.4.x and higher in ECB mode

<?php $key = "this is a very secret key"; $input = "Let us meet at 9 o'clock at the secret place."; $td = mcrypt_module_open ('tripledes', '', 'ecb', ''); $iv = mcrypt_create_iv (mcrypt_enc_get_iv_size ($td), MCRYPT_RAND); mcrypt_generic_init ($td, $key, $iv); $encrypted_data = mcrypt_generic ($td, $input); mcrypt_generic_end ($td); ?>
This example will give you the encrypted data as a string in $encrypted_data. For a full example see mcrypt_module_open().

Requirements

These functions work using mcrypt.

If you linked against libmcrypt 2.4.x or higher, the following additional block algorithms are supported: CAST, LOKI97, RIJNDAEL, SAFERPLUS, SERPENT and the following stream ciphers: ENIGMA (crypt), PANAMA, RC4 and WAKE. With libmcrypt 2.4.x or higher another cipher mode is also available; nOFB.

Installation

To use it, download libmcrypt-x.x.tar.gz from here and follow the included installation instructions. You need to compile PHP with the --with-mcrypt parameter to enable this extension. Make sure you compile libmcrypt with the option --disable-posix-threads.

Runtime Configuration

Resource types

Toto rezšíření nemá definován žádný typ prostředku (resource).

Predefined constants

Mcrypt can operate in four block cipher modes (CBC, OFB, CFB, and ECB). If linked against libmcrypt-2.4.x or higher the functions can also operate in the block cipher mode nOFB and in STREAM mode. Below you find a list with all supported encryption modes together with the constants that are defines for the encryption mode. For a more complete reference and discussion see Applied Cryptography by Schneier (ISBN 0-471-11709-9).

MCRYPT_MODE_ECB (electronic codebook) is suitable for random data, such as encrypting other keys. Since data there is short and random, the disadvantages of ECB have a favorable negative effect.
MCRYPT_MODE_CBC (cipher block chaining) is especially suitable for encrypting files where the security is increased over ECB significantly.
MCRYPT_MODE_CFB (cipher feedback) is the best mode for encrypting byte streams where single bytes must be encrypted.
MCRYPT_MODE_OFB (output feedback, in 8bit) is comparable to CFB, but can be used in applications where error propagation cannot be tolerated. It's insecure (because it operates in 8bit mode) so it is not recommended to use it.
MCRYPT_MODE_NOFB (output feedback, in nbit) is comparable to OFB, but more secure because it operates on the block size of the algorithm.
MCRYPT_MODE_STREAM is an extra mode to include some stream algorithms like WAKE or RC4.

Here is a list of ciphers which are currently supported by the mcrypt extension. For a complete list of supported ciphers, see the defines at the end of mcrypt.h. The general rule with the mcrypt-2.2.x API is that you can access the cipher from PHP with MCRYPT_ciphername. With the libmcrypt-2.4.x and libmcrypt-2.5.x API these constants also work, but it is possible to specify the name of the cipher as a string with a call to mcrypt_module_open().

MCRYPT_3DES
MCRYPT_ARCFOUR_IV (libmcrypt > 2.4.x only)
MCRYPT_ARCFOUR (libmcrypt > 2.4.x only)
MCRYPT_BLOWFISH
MCRYPT_CAST_128
MCRYPT_CAST_256
MCRYPT_CRYPT
MCRYPT_DES
MCRYPT_DES_COMPAT (libmcrypt 2.2.x only)
MCRYPT_ENIGMA (libmcrypt > 2.4.x only, alias for MCRYPT_CRYPT)
MCRYPT_GOST
MCRYPT_IDEA (non-free)
MCRYPT_LOKI97 (libmcrypt > 2.4.x only)
MCRYPT_MARS (libmcrypt > 2.4.x only, non-free)
MCRYPT_PANAMA (libmcrypt > 2.4.x only)
MCRYPT_RIJNDAEL_128 (libmcrypt > 2.4.x only)
MCRYPT_RIJNDAEL_192 (libmcrypt > 2.4.x only)
MCRYPT_RIJNDAEL_256 (libmcrypt > 2.4.x only)
MCRYPT_RC2
MCRYPT_RC4 (libmcrypt 2.2.x only)
MCRYPT_RC6 (libmcrypt > 2.4.x only)
MCRYPT_RC6_128 (libmcrypt 2.2.x only)
MCRYPT_RC6_192 (libmcrypt 2.2.x only)
MCRYPT_RC6_256 (libmcrypt 2.2.x only)
MCRYPT_SAFER64
MCRYPT_SAFER128
MCRYPT_SAFERPLUS (libmcrypt > 2.4.x only)
MCRYPT_SERPENT(libmcrypt > 2.4.x only)
MCRYPT_SERPENT_128 (libmcrypt 2.2.x only)
MCRYPT_SERPENT_192 (libmcrypt 2.2.x only)
MCRYPT_SERPENT_256 (libmcrypt 2.2.x only)
MCRYPT_SKIPJACK (libmcrypt > 2.4.x only)
MCRYPT_TEAN (libmcrypt 2.2.x only)
MCRYPT_THREEWAY
MCRYPT_TRIPLEDES (libmcrypt > 2.4.x only)
MCRYPT_TWOFISH (for older mcrypt 2.x versions, or mcrypt > 2.4.x )
MCRYPT_TWOFISH128 (TWOFISHxxx are available in newer 2.x versions, but not in the 2.4.x versions)
MCRYPT_TWOFISH192
MCRYPT_TWOFISH256
MCRYPT_WAKE (libmcrypt > 2.4.x only)
MCRYPT_XTEA (libmcrypt > 2.4.x only)

You must (in CFB and OFB mode) or can (in CBC mode) supply an initialization vector (IV) to the respective cipher function. The IV must be unique and must be the same when decrypting/encrypting. With data which is stored encrypted, you can take the output of a function of the index under which the data is stored (e.g. the MD5 key of the filename). Alternatively, you can transmit the IV together with the encrypted data (see chapter 9.3 of Applied Cryptography by Schneier (ISBN 0-471-11709-9) for a discussion of this topic).

Obsah
mcrypt_cbc -- Encrypt/decrypt data in CBC mode
mcrypt_cfb -- Encrypt/decrypt data in CFB mode
mcrypt_create_iv -- Create an initialization vector (IV) from a random source
mcrypt_decrypt -- Decrypts crypttext with given parameters
mcrypt_ecb -- Encrypt/decrypt data in ECB mode
mcrypt_enc_get_algorithms_name -- Returns the name of the opened algorithm
mcrypt_enc_get_block_size -- Returns the blocksize of the opened algorithm
mcrypt_enc_get_iv_size -- Returns the size of the IV of the opened algorithm
mcrypt_enc_get_key_size -- Returns the maximum supported keysize of the opened mode
mcrypt_enc_get_modes_name -- Returns the name of the opened mode
mcrypt_enc_get_supported_key_sizes -- Returns an array with the supported keysizes of the opened algorithm
mcrypt_enc_is_block_algorithm_mode -- Checks whether the encryption of the opened mode works on blocks
mcrypt_enc_is_block_algorithm -- Checks whether the algorithm of the opened mode is a block algorithm
mcrypt_enc_is_block_mode -- Checks whether the opened mode outputs blocks
mcrypt_enc_self_test -- This function runs a self test on the opened module
mcrypt_encrypt -- Encrypts plaintext with given parameters
mcrypt_generic_deinit -- This function deinitializes an encryption module
mcrypt_generic_end -- This function terminates encryption
mcrypt_generic_init -- This function initializes all buffers needed for encryption
mcrypt_generic -- This function encrypts data
mcrypt_get_block_size -- Get the block size of the specified cipher
mcrypt_get_cipher_name -- Get the name of the specified cipher
mcrypt_get_iv_size -- Returns the size of the IV belonging to a specific cipher/mode combination
mcrypt_get_key_size -- Get the key size of the specified cipher
mcrypt_list_algorithms -- Get an array of all supported ciphers
mcrypt_list_modes -- Get an array of all supported modes
mcrypt_module_close -- Close the mcrypt module
mcrypt_module_get_algo_block_size -- Returns the blocksize of the specified algorithm
mcrypt_module_get_algo_key_size -- Returns the maximum supported keysize of the opened mode
mcrypt_module_get_supported_key_sizes -- Returns an array with the supported keysizes of the opened algorithm
mcrypt_module_is_block_algorithm_mode -- This function returns if the the specified module is a block algorithm or not
mcrypt_module_is_block_algorithm -- This function checks whether the specified algorithm is a block algorithm
mcrypt_module_is_block_mode -- This function returns if the the specified mode outputs blocks or not
mcrypt_module_open -- This function opens the module of the algorithm and the mode to be used
mcrypt_module_self_test -- This function runs a self test on the specified module
mcrypt_ofb -- Encrypt/decrypt data in OFB mode
mdecrypt_generic -- This function decrypts data

The source can be MCRYPT_RAND (system random number generator), MCRYPT_DEV_RANDOM (read data from /dev/random) and MCRYPT_DEV_URANDOM (read data from /dev/urandom). If you use MCRYPT_RAND, make sure to call srand() before to initialize the random number generator.

Příklad 1. mcrypt_create_iv() example

<?php $size = mcrypt_get_iv_size (MCRYPT_CAST_256, MCRYPT_MODE_CFB); $iv = mcrypt_create_iv ($size, MCRYPT_DEV_RANDOM); ?>

The IV is only meant to give an alternative seed to the encryption routines. This IV does not need to be secret at all, though it can be desirable. You even can send it along with your ciphertext without loosing security.

More information can be found at http://www.ciphersbyritter.com/GLOSSARY.HTM#IV, http://fn2.freenet.edmonton.ab.ca/~jsavard/crypto/co0409.htm and in chapter 9.3 of Applied Cryptography by Schneier (ISBN 0-471-11709-9) for a discussion of this topic.

mcrypt_decrypt

(PHP 4 >= 4.0.2)

mcrypt_decrypt -- Decrypts crypttext with given parameters

Description

string mcrypt_decrypt ( string cipher, string key, string data, string mode [, string iv])

mcrypt_decrypt() decrypts the data and returns the unencrypted data.

Cipher is one of the MCRYPT_ciphername constants of the name of the algorithm as string.

Key is the key with which the data is encrypted. If it's smaller that the required keysize, it is padded with '\0'.

string mcrypt_enc_get_modes_name ( resource td)

This function returns the name of the mode.

Příklad 1. mcrypt_enc_get_modes_name() example

<?php $td = mcrypt_module_open (MCRYPT_CAST_256, '', MCRYPT_MODE_CFB, ''); echo mcrypt_enc_get_modes_name($td). "\n"; $td = mcrypt_module_open ('cast-256', '', 'ecb', ''); echo mcrypt_enc_get_modes_name($td). "\n"; ?> Prints: CFB ECB

mcrypt_enc_get_supported_key_sizes

(PHP 4 >= 4.0.2)

mcrypt_enc_get_supported_key_sizes -- Returns an array with the supported keysizes of the opened algorithm

Description

array mcrypt_enc_get_supported_key_sizes ( resource td)

string mcrypt_encrypt ( string cipher, string key, string data, string mode [, string iv])

mcrypt_encrypt() encrypts the data and returns the encrypted data.

Cipher is one of the MCRYPT_ciphername constants of the name of the algorithm as string.

Key is the key with which the data will be encrypted. If it's smaller that the required keysize, it is padded with '\0'. It is better not to use ASCII strings for keys. It is recommended to use the mhash functions to create a key from a string.

Data is the data that will be encrypted with the given cipher and mode. If the size of the data is not n * blocksize, the data will be padded with '\0'. The returned crypttext can be larger that the size of the data that is given by data.

int mcrypt_generic_init ( resource td, string key, string iv)

The maximum length of the key should be the one obtained by calling mcrypt_enc_get_key_size() and every value smaller than this is legal. The IV should normally have the size of the algorithms block size, but you must obtain the size by calling mcrypt_enc_get_iv_size(). IV is ignored in ECB. IV MUST exist in CFB, CBC, STREAM, nOFB and OFB modes. It needs to be random and unique (but not secret). The same IV must be used for encryption/decryption. If you do not want to use it you should set it to zeros, but this is not recommended. The function returns a negative value on error.

You need to call this function before every call to mcrypt_generic() or mdecrypt_generic().

See for an example mcrypt_module_open() and the entry on mcrypt_generic_deinit().

mcrypt_generic

(PHP 4 >= 4.0.2)

mcrypt_generic -- This function encrypts data

int mcrypt_get_iv_size ( resource td)

int mcrypt_get_iv_size ( string cipher, string mode)

The first prototype is when linked against libmcrypt 2.2.x, the second when linked against libmcrypt 2.4.x or higher.

mcrypt_get_iv_size() returns the size of the Initialisation Vector (IV) in bytes. On error the function returns FALSE. If the IV is ignored in the specified cipher/mode combination zero is returned.

bool mcrypt_module_close ( resource td)

array mcrypt_module_get_supported_key_sizes ( string algorithm [, string lib_dir])

resource mcrypt_module_open ( string algorithm, string algorithm_directory, string mode, string mode_directory)

This function opens the module of the algorithm and the mode to be used. The name of the algorithm is specified in algorithm, eg. "twofish" or is one of the MCRYPT_ciphername constants. The module is closed by calling mcrypt_module_close(). Normally it returns an encryption descriptor, or FALSE on error.

The algorithm_directory and mode_directory are used to locate the encryption modules. When you supply a directory name, it is used. When you set one of these to the empty string (""), the value set by the mcrypt.algorithms_dir or mcrypt.modes_dir ini-directive is used. When these are not set, the default directories that are used are the ones that were compiled in into libmcrypt (usally /usr/local/lib/libmcrypt).

string mdecrypt_generic ( resource td, string data)

This function decrypts data. Note that the length of the returned string can in fact be longer then the unencrypted string, due to the padding of the data.

Příklad 1. mdecrypt_generic() Example

<?php /* Data */ $key = 'this is a very long key, even too long for the cipher'; $plain_text = 'very important data'; /* Open module, and create IV */ $td = mcrypt_module_open ('des', '', 'ecb', ''); $key = substr ($key, 0, mcrypt_enc_get_key_size ($td)); $iv_size = mcrypt_enc_get_iv_size ($td); $iv = mcrypt_create_iv ($iv_size, MCRYPT_RAND); /* Initialize encryption handle */ if (mcrypt_generic_init ($td, $key, $iv) != -1) { /* Encrypt data */ $c_t = mcrypt_generic ($td, $plain_text); mcrypt_generic_deinit ($td); /* Reinitialize buffers for decryption */ mcrypt_generic_init ($td, $key, $iv); $p_t = mdecrypt_generic ($td, $c_t); /* Clean up */ mcrypt_generic_deinit ($td); mcrypt_module_close ($td); } if (strncmp ($p_t, $plain_text, strlen($plain_text)) == 0) { echo "ok\n"; } else { echo "error\n"; } ?>

The above example shows how to check if the data before the encryption is the same as the data after the decryption. It is very important to reinitialize the encryption buffer with mcrypt_generic_init() before you try to decrypt the data.

The decryption handle should alwayws be initialized with mcrypt_generic_init() with a key and an IV before calling this function. Where the encryption is done, you should free the encryption buffers by calling mcrypt_generic_deinit(). See mcrypt_module_open() for an example.

LVI. Mhash funkce

Tyto funkce jsou určeny pro práci s mhash.

Toto je interface ke knihvně mhash. mhash podporuje širokou škálu hash algoritmů jako např. MD5, SHA1, GOST a mnoho jiných.

Pokud chcete tyto funkce používat, stáhněte si mhash distribuci z its web site a postupujte podle přiložených instrukcí k instalaci. K aktivaci tohoto modulu budete muset zkompilovat PHP s volbou --with-mhash

Mhash se dá použít k vytváření kontrolních součtů, message digests, message authentication codes, and more.

Příklad 1. Compute the MD5 digest and hmac and print it out as hex

<?php $input = "what do ya want for nothing?"; $hash = mhash (MHASH_MD5, $input); print "The hash is ".bin2hex ($hash)."\n<br>"; $hash = mhash (MHASH_MD5, $input, "Jefe"); print "The hmac is ".bin2hex ($hash)."\n<br>"; ?>
This will produce:

The hash is d03cb659cbf9192dcd066272249f8412 The hmac is 750c783e6ab0b503eaa86e310a5db738
Kompletní seznam podporovaných hashů viz dokumentaci mhash. Obecným pravidlem je, že hash algoritmus je dostupný z PHP pomocí MHASH_NAZEVHASHE. Například TIGER se v PHP používá pomocí konstanty MHASH_TIGER.

Zde je seznam hashů podporovaných mhashem v současné době. Pokud zde není některý hash jmenován, ale v dokumentaci mhashe je uveden jako podporovaný, můžete bezpečně předpokládat, že je tato dokumentace zastaralá.

MHASH_MD5
MHASH_SHA1
MHASH_HAVAL256
MHASH_HAVAL192
MHASH_HAVAL160
MHASH_HAVAL128
MHASH_RIPEMD160
MHASH_GOST
MHASH_TIGER
MHASH_CRC32
MHASH_CRC32B

Obsah
mhash_count -- Získat nejvyšší dostupné hash id
mhash_get_block_size -- Získat velikost bloku určeného hashe
mhash_get_hash_name -- Získat název zadaného hashe
mhash_keygen_s2k -- Vygenerovat klíč
mhash -- Spočítat hash

Příklad 1. Ukázka mhash_get_hash_name()

<?php $hash = MHASH_MD5; print mhash_get_hash_name ($hash); ?>
Výše uvedená ukázka vytiskne:

MD5

mhash_keygen_s2k

(PHP 4 >= 4.0.4)

mhash_keygen_s2k -- Vygenerovat klíč

Popis

string mhash_keygen_s2k ( int hash, string password, string salt, int bytes)

mhash_keygen_s2k() generuje klíč, který je bytes dlouhý, z předaného hesla. Toto je Salted S2K algoritmus specifikovaný v OpenPGP dokumentu (RFC 2440). Tento algoritmus použije k vytvoření klíče hash algoritmus. salt musí být pro každý generovaný klíč jiný a dostatečně náhodný, aby vytvořil různé klíče. Salt musí být při kontrole klíčů znám, tudíž je dobrý nápad ho připojit ke klíči. Salt ma pevnou délku 8 bytů a pokud dodáte méně bytů, bude doplněn nulami. Pamatujte, že uživatelsky určená hesla nejsou vhodná k použití jako klíče, protože uživatelé obvykle volí klíče, které mohou napsat na klávesnici. Tato hesla využívají pouze 6 až 7 bytů na znak (nebo méně). Je velmi vhodné na uživateli určené klíče použít nějakou transformaci (jako je tato funkce).

mhash

(PHP 3>= 3.0.9, PHP 4 )

mhash -- Spočítat hash

Popis

string mhash ( int hash, string data, string [ key ])

mhash() aplikuje hash funkci určenou argumentem hash na data a vrací výsledný hash (také nazývaný digest). Pokud je předán key, vrací výsledný HMAC. HMAC is keyed hashing for message authentication, or simply a message digest that depends on the specified key. Not all algorithms supported in mhash can be used in HMAC mode. In case of an error returns FALSE.

LVII. Mimetype Functions

Úvod

The functions in this module try to guess the content type and encoding of a file by looking for certain magic byte sequences at specific positions within the file. While this is not a bullet proof approach the heuristics used do a very good job.

This extension is derivated from Apache mod_mime_magic, which is itself based on the file command maintaind by Ian F. Darwin. See the source code for further historic and copyright information.

Požadavky

Tyto funkce jsou k dispozici jako součást standardního modulu, který je vždy dostupný.

Instalace

The extension needs a copy of the magic.mime as distributed with the file command. This file also part of most recent Linux distributions and usually stored in the /usr/share/misc directory.

Konfigurace běhu

Tabulka 1. MIME magic Configuration options

Name	Default	Changeable
mime_magic.magicfile	"/usr/share/misc/magic.mime"	PHP_INI_SYSTEM

Typy prostředků

Toto rezšíření nemá definován žádný typ prostředku (resource).

Předdefinované konstanty

Toto rozšíření nemá definovány žádné konstanty.

Obsah
mime_content_type -- Detect MIME Content-type for a file

mime_content_type

(PHP 4 CVS only)

mime_content_type -- Detect MIME Content-type for a file

Description

string mime_content_type ( string filename)

Returns the MIME content type for a file as determined by using information from the magic.mime file. Content types are returned in MIME format, like text/plain or application/octet-stream.

LVIII. Microsoft SQL Server functions

The MSSQL extension is available on Win32 systems only. You can use the Sybase extension to connect to MSSQL databases from other platforms.

These functions allow you to access MS SQL Server database. The extension requires the MS SQL Client Tools to be installed on the system where PHP is installed. The Client Tools can be installed from the MS SQL Server CD or by copying ntwdblib.dll from \winnt\system32 on the server to \winnt\system32 on the PHP box. Copying ntwdblib.dll will only provide access. Configuration of the client will require installation of all the tools.

The MSSQL extension is enabled by adding extension=php_mssql.dll to php.ini.

Obsah
mssql_bind -- Adds a parameter to a stored procedure or a remote stored procedure
mssql_close -- Close MS SQL Server connection
mssql_connect -- Open MS SQL server connection
mssql_data_seek -- Move internal row pointer
mssql_execute -- Executes a stored procedure on a MS SQL server database
mssql_fetch_array -- Fetch row as array
mssql_fetch_assoc -- Returns an associative array of the current row in the result set specified by result_id
mssql_fetch_batch -- Returns the next batch of records
mssql_fetch_field -- Get field information
mssql_fetch_object -- Fetch row as object
mssql_fetch_row -- Get row as enumerated array
mssql_field_length -- Get the length of a field
mssql_field_name -- Get the name of a field
mssql_field_seek -- Set field offset
mssql_field_type -- Get the type of a field
mssql_free_result -- Free result memory
mssql_get_last_message -- Returns the last message from server (over min_message_severity?)
mssql_guid_string -- Converts a 16 byte binary GUID to a string
mssql_init -- Initializes a stored procedure or a remote stored procedure
mssql_min_error_severity -- Sets the lower error severity
mssql_min_message_severity -- Sets the lower message severity
mssql_next_result -- Move the internal result pointer to the next result
mssql_num_fields -- Get number of fields in result
mssql_num_rows -- Get number of rows in result
mssql_pconnect -- Open persistent MS SQL connection
mssql_query -- Send MS SQL query
mssql_result -- Get result data
mssql_rows_affected -- Returns the number of records affected by the query
mssql_select_db -- Select MS SQL database

mssql_bind

(PHP 4 >= 4.1.0)

int mssql_fetch_array ( int result)

Returns: An array that corresponds to the fetched row, or FALSE if there are no more rows.

object mssql_fetch_field ( int result [, int field_offset])

Returns an object containing field information.

mssql_fetch_field() can be used in order to obtain information about fields in a certain query result. If the field offset isn't specified, the next field that wasn't yet retrieved by mssql_fetch_field() is retrieved.

The properties of the object are:

name - column name. if the column is a result of a function, this property is set to computed#N, where #N is a serial number.
column_source - the table from which the column was taken
max_length - maximum length of the column
numeric - 1 if the column is numeric

mssql_fetch_object

(PHP 3)

mssql_fetch_object -- Fetch row as object

Description

int mssql_fetch_object ( int result)

Returns: An object with properties that correspond to the fetched row, or FALSE if there are no more rows.

mssql_fetch_object() is similar to mssql_fetch_array(), with one difference - an object is returned, instead of an array. Indirectly, that means that you can only access the data by the field names, and not by their offsets (numbers are illegal property names).

Speed-wise, the function is identical to mssql_fetch_array(), and almost as quick as mssql_fetch_row() (the difference is insignificant).

mssql_fetch_row

(PHP 3, PHP 4 )

mssql_fetch_row -- Get row as enumerated array

Description

array mssql_fetch_row ( int result)

Returns: An array that corresponds to the fetched row, or FALSE if there are no more rows.

mssql_fetch_row() fetches one row of data from the result associated with the specified result identifier. The row is returned as an array. Each result column is stored in an array offset, starting at offset 0.

Subsequent call to mssql_fetch_rows() would return the next row in the result set, or FALSE if there are no more rows.

See also: mssql_fetch_array(), mssql_fetch_object(), mssql_data_seek(), mssql_fetch_lengths(), and mssql_result().

mssql_field_length

(PHP 3>= 3.0.3, PHP 4 )

mssql_field_length -- Get the length of a field

Description

mssql_free_result() only needs to be called if you are worried about using too much memory while your script is running. All result memory will automatically be freed when the script ends. You may call mssql_free_result() with the result identifier as an argument and the associated result memory will be freed.

mssql_get_last_message

(PHP 3, PHP 4 )

bool mssql_next_result ( int result_id)

When sending more than one SQL statement to the server or executing a stored procedure with multiple results, it will cause the server to return multiple result sets. This function will test for additional results available form the server. If an additional result set exists it will free the existing result set and prepare to fetch the rows from the new result set. The function will return TRUE if an additional result set was available or FALSE otherwise.

Příklad 1. mssql_next_result() example

<?php
    $link = mssql_connect ("localhost", "userid", "secret");
    mssql_select_db("MyDB", $link);
    $SQL = "Select * from table1 select * from table2";
    $rs = mssql_query($SQL, $link);
    do {
        while ($row = mssql_fetch_row($rs)) {
        }
    } while (mssql_next_result($rs));
    mssql_free_result($rs);
    mssql_close ($link);
?>

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

mssql_select_db

(PHP 3, PHP 4 )

mssql_select_db -- Select MS SQL database

Description

int mssql_select_db ( string database_name [, int link_identifier])

Returns: TRUE on success, FALSE on error

mssql_select_db() sets the current active database on the server that's associated with the specified link identifier. If no link identifier is specified, the last opened link is assumed. If no link is open, the function will try to establish a link as if mssql_connect() was called, and use it.

Every subsequent call to mssql_query() will be made on the active database.

LIX. Ming functions for Flash

Varování

Introduction

Ming is an open-source (LGPL) library which allows you to create SWF ("Flash") format movies. Ming supports almost all of Flash 4's features, including: shapes, gradients, bitmaps (pngs and jpegs), morphs ("shape tweens"), text, buttons, actions, sprites ("movie clips"), streaming mp3, and color transforms--the only thing that's missing is sound events.

Ming is not an acronym.

Note that all values specifying length, distance, size, etc. are in "twips", twenty units per pixel. That's pretty much arbitrary, though, since the player scales the movie to whatever pixel size is specified in the embed/object tag, or the entire frame if not embedded.

Ming offers a number of advantages over the existing PHP/libswf module. You can use Ming anywhere you can compile the code, whereas libswf is closed-source and only available for a few platforms, Windows not one of them. Ming provides some insulation from the mundane details of the SWF file format, wrapping the movie elements in PHP objects. Also, Ming is still being maintained; if there's a feature that you want to see, just let us know ming@opaque.net.

Ming was added in PHP 4.0.5.

Installation

To use Ming with PHP, you first need to build and install the Ming library. Source code and installation instructions are available at the Ming home page : http://www.opaque.net/ming/ along with examples, a small tutorial, and the latest news.

Download the ming archive. Unpack the archive. Go in the Ming directory. make. make install.

This will build libming.so and install it into /usr/lib/, and copy ming.h into /usr/include/. Edit the PREFIX= line in the Makefile to change the installation directory.

built into php (unix)

       mkdir <phpdir>/ext/ming
       cp php_ext/* <phpdir>/ext/ming
       cd <phpdir>
       ./buildconf
       ./configure --with-ming <other config options>

Build and install php as usual, Restart web server if necessary

built into php (unix)

download php_ming.so.gz. uncompress it and copy it to your php modules directory. (you can find your php module directory by running php-config --extension-dir). Now either just add extension=php_ming.so to your php.ini file, or put dl('php_ming.so'); at the head of all of your Ming scripts.

How to use Ming

Ming introduces 13 new objects in PHP, all with matching methods and attributes. To use them, you need to know about objects.

Obsah
ming_setcubicthreshold -- Set cubic threshold (?)
ming_setscale -- Set scale (?)
ming_useswfversion -- Use SWF version (?)
SWFAction -- Creates a new Action.
SWFBitmap->getHeight -- Returns the bitmap's height.
SWFBitmap->getWidth -- Returns the bitmap's width.
SWFBitmap -- Loads Bitmap object
swfbutton_keypress -- Returns the action flag for keyPress(char)
SWFbutton->addAction -- Adds an action
SWFbutton->addShape -- Adds a shape to a button
SWFbutton->setAction -- Sets the action
SWFbutton->setdown -- Alias for addShape(shape, SWFBUTTON_DOWN))
SWFbutton->setHit -- Alias for addShape(shape, SWFBUTTON_HIT)
SWFbutton->setOver -- Alias for addShape(shape, SWFBUTTON_OVER)
SWFbutton->setUp -- Alias for addShape(shape, SWFBUTTON_UP)
SWFbutton -- Creates a new Button.
SWFDisplayItem->addColor -- Adds the given color to this item's color transform.
SWFDisplayItem->move -- Moves object in relative coordinates.
SWFDisplayItem->moveTo -- Moves object in global coordinates.
SWFDisplayItem->multColor -- Multiplies the item's color transform.
SWFDisplayItem->remove -- Removes the object from the movie
SWFDisplayItem->Rotate -- Rotates in relative coordinates.
SWFDisplayItem->rotateTo -- Rotates the object in global coordinates.
SWFDisplayItem->scale -- Scales the object in relative coordinates.
SWFDisplayItem->scaleTo -- Scales the object in global coordinates.
SWFDisplayItem->setDepth -- Sets z-order
SWFDisplayItem->setName -- Sets the object's name
SWFDisplayItem->setRatio -- Sets the object's ratio.
SWFDisplayItem->skewX -- Sets the X-skew.
SWFDisplayItem->skewXTo -- Sets the X-skew.
SWFDisplayItem->skewY -- Sets the Y-skew.
SWFDisplayItem->skewYTo -- Sets the Y-skew.
SWFDisplayItem -- Creates a new displayitem object.
SWFFill->moveTo -- Moves fill origin
SWFFill->rotateTo -- Sets fill's rotation
SWFFill->scaleTo -- Sets fill's scale
SWFFill->skewXTo -- Sets fill x-skew
SWFFill->skewYTo -- Sets fill y-skew
SWFFill -- Loads SWFFill object
swffont->getwidth -- Returns the string's width
SWFFont -- Loads a font definition
SWFGradient->addEntry -- Adds an entry to the gradient list.
SWFGradient -- Creates a gradient object
SWFMorph->getshape1 -- Gets a handle to the starting shape
SWFMorph->getshape2 -- Gets a handle to the ending shape
SWFMorph -- Creates a new SWFMorph object.
SWFMovie->add -- Adds any type of data to a movie.
SWFMovie->nextframe -- Moves to the next frame of the animation.
SWFMovie->output -- Dumps your lovingly prepared movie out.
SWFMovie->remove -- Removes the object instance from the display list.
SWFMovie->save -- Saves your movie in a file.
SWFMovie->setbackground -- Sets the background color.
SWFMovie->setdimension -- Sets the movie's width and height.
SWFMovie->setframes -- Sets the total number of frames in the animation.
SWFMovie->setrate -- Sets the animation's frame rate.
SWFMovie->streammp3 -- Streams a MP3 file.
SWFMovie -- Creates a new movie object, representing an SWF version 4 movie.
SWFShape->addFill -- Adds a solid fill to the shape.
SWFShape->drawCurve -- Draws a curve (relative).
SWFShape->drawCurveTo -- Draws a curve.
SWFShape->drawLine -- Draws a line (relative).
SWFShape->drawLineTo -- Draws a line.
SWFShape->movePen -- Moves the shape's pen (relative).
SWFShape->movePenTo -- Moves the shape's pen.
SWFShape->setLeftFill -- Sets left rasterizing color.
SWFShape->setLine -- Sets the shape's line style.
SWFShape->setRightFill -- Sets right rasterizing color.
SWFShape -- Creates a new shape object.
SWFSprite->add -- Adds an object to a sprite
SWFSprite->nextframe -- Moves to the next frame of the animation.
SWFSprite->remove -- Removes an object to a sprite
SWFSprite->setframes -- Sets the total number of frames in the animation.
SWFSprite -- Creates a movie clip (a sprite)
SWFText->addString -- Draws a string
SWFText->getWidth -- Computes string's width
SWFText->moveTo -- Moves the pen
SWFText->setColor -- Sets the current font color
SWFText->setFont -- Sets the current font
SWFText->setHeight -- Sets the current font height
SWFText->setSpacing -- Sets the current font spacing
SWFText -- Creates a new SWFText object.
SWFTextField->addstring -- Concatenates the given string to the text field
SWFTextField->align -- Sets the text field alignment
SWFTextField->setbounds -- Sets the text field width and height
SWFTextField->setcolor -- Sets the color of the text field.
SWFTextField->setFont -- Sets the text field font
SWFTextField->setHeight -- Sets the font height of this text field font.
SWFTextField->setindentation -- Sets the indentation of the first line.
SWFTextField->setLeftMargin -- Sets the left margin width of the text field.
SWFTextField->setLineSpacing -- Sets the line spacing of the text field.
SWFTextField->setMargins -- Sets the margins width of the text field.
SWFTextField->setname -- Sets the variable name
SWFTextField->setrightMargin -- Sets the right margin width of the text field.
SWFTextField -- Creates a text field object

The script syntax is based on the C language, but with a lot taken out- the SWF bytecode machine is just too simpleminded to do a lot of things we might like. For instance, we can't implement function calls without a tremendous amount of hackery because the jump bytecode has a hardcoded offset value. No pushing your calling address to the stack and returning- every function would have to know exactly where to return to.

So what's left? The compiler recognises the following tokens:

break
for
continue
if
else
do
while

There is no typed data; all values in the SWF action machine are stored as strings. The following functions can be used in expressions:

time(): Returns the number of milliseconds (?) elapsed since the movie started.
random(seed): Returns a pseudo-random number in the range 0-seed.
length(expr): Returns the length of the given expression.
int(number): Returns the given number rounded down to the nearest integer.
concat(expr, expr): Returns the concatenation of the given expressions.
ord(expr): Returns the ASCII code for the given character
chr(num): Returns the character for the given ASCII code
substr(string, location, length): Returns the substring of length length at location location of the given string string.

Additionally, the following commands may be used:

duplicateClip(clip, name, depth): Duplicate the named movie clip (aka sprite). The new movie clip has name name and is at depth depth.
removeClip(expr): Removes the named movie clip.
trace(expr): Write the given expression to the trace log. Doubtful that the browser plugin does anything with this.
startDrag(target, lock, [left, top, right, bottom]): Start dragging the movie clip target. The lock argument indicates whether to lock the mouse (?)- use 0 (FALSE) or 1 (TRUE). Optional parameters define a bounding area for the dragging.
stopDrag(): Stop dragging my heart around. And this movie clip, too.
callFrame(expr): Call the named frame as a function.
getURL(url, target, [method]): Load the given URL into the named target. The target argument corresponds to HTML document targets (such as "_top" or "_blank"). The optional method argument can be POST or GET if you want to submit variables back to the server.
loadMovie(url, target): Load the given URL into the named target. The target argument can be a frame name (I think), or one of the magical values "_level0" (replaces current movie) or "_level1" (loads new movie on top of current movie).
nextFrame(): Go to the next frame.
prevFrame(): Go to the last (or, rather, previous) frame.
play(): Start playing the movie.
stop(): Stop playing the movie.
toggleQuality(): Toggle between high and low quality.
stopSounds(): Stop playing all sounds.
gotoFrame(num): Go to frame number num. Frame numbers start at 0.
gotoFrame(name): Go to the frame named name. Which does a lot of good, since I haven't added frame labels yet.
setTarget(expr): Sets the context for action. Or so they say- I really have no idea what this does.

And there's one weird extra thing. The expression frameLoaded(num) can be used in if statements and while loops to check if the given frame number has been loaded yet. Well, it's supposed to, anyway, but I've never tested it and I seriously doubt it actually works. You can just use /:framesLoaded instead.

Movie clips (all together now- aka sprites) have properties. You can read all of them (or can you?), you can set some of them, and here they are:

x
y
xScale
yScale
currentFrame - (read-only)
totalFrames - (read-only)
alpha - transparency level
visible - 1=on, 0=off (?)
width - (read-only)
height - (read-only)
rotation
target - (read-only) (???)
framesLoaded - (read-only)
name
dropTarget - (read-only) (???)
url - (read-only) (???)
highQuality - 1=high, 0=low (?)
focusRect - (???)
soundBufTime - (???)

So, setting a sprite's x position is as simple as /box.x = 100;. Why the slash in front of the box, though? That's how flash keeps track of the sprites in the movie, just like a unix filesystem- here it shows that box is at the top level. If the sprite named box had another sprite named biff inside of it, you'd set its x position with /box/biff.x = 100;. At least, I think so; correct me if I'm wrong here.

This simple example will move the red square across the window.

Příklad 1. swfaction() example

<?php $s = new SWFShape(); $f = $s->addFill(0xff, 0, 0); $s->setRightFill($f); $s->movePenTo(-500,-500); $s->drawLineTo(500,-500); $s->drawLineTo(500,500); $s->drawLineTo(-500,500); $s->drawLineTo(-500,-500); $p = new SWFSprite(); $i = $p->add($s); $i->setDepth(1); $p->nextFrame(); for($n=0; $n<5; ++$n) { $i->rotate(-15); $p->nextFrame(); } $m = new SWFMovie(); $m->setBackground(0xff, 0xff, 0xff); $m->setDimension(6000,4000); $i = $m->add($p); $i->setDepth(1); $i->moveTo(-500,2000); $i->setName("box"); $m->add(new SWFAction("/box.x += 3;")); $m->nextFrame(); $m->add(new SWFAction("gotoFrame(0); play();")); $m->nextFrame(); header('Content-type: application/x-shockwave-flash'); $m->output(); ?>

new swfbitmap ( string filename [, int alphafilename])

Varování

swfbitmap() creates a new SWFBitmap object from the Jpeg or DBL file named filename. alphafilename indicates a MSK file to be used as an alpha mask for a Jpeg image.

Poznámka: We can only deal with baseline (frame 0) jpegs, no baseline optimized or progressive scan jpegs!

SWFBitmap has the following methods : swfbitmap->getwidth() and swfbitmap->getheight().

You can't import png images directly, though- have to use the png2dbl utility to make a dbl ("define bits lossless") file from the png. The reason for this is that I don't want a dependency on the png library in ming- autoconf should solve this, but that's not set up yet.

Příklad 1. Import PNG files

<?php $s = new SWFShape(); $f = $s->addFill(new SWFBitmap("png.dbl")); $s->setRightFill($f); $s->drawLine(32, 0); $s->drawLine(0, 32); $s->drawLine(-32, 0); $s->drawLine(0, -32); $m = new SWFMovie(); $m->setDimension(32, 32); $m->add($s); header('Content-type: application/x-shockwave-flash'); $m->output(); ?>

And you can put an alpha mask on a jpeg fill.

Příklad 2. swfbitmap() example

<?php $s = new SWFShape(); // .msk file generated with "gif2mask" utility $f = $s->addFill(new SWFBitmap("alphafill.jpg", "alphafill.msk")); $s->setRightFill($f); $s->drawLine(640, 0); $s->drawLine(0, 480); $s->drawLine(-640, 0); $s->drawLine(0, -480); $c = new SWFShape(); $c->setRightFill($c->addFill(0x99, 0x99, 0x99)); $c->drawLine(40, 0); $c->drawLine(0, 40); $c->drawLine(-40, 0); $c->drawLine(0, -40); $m = new SWFMovie(); $m->setDimension(640, 480); $m->setBackground(0xcc, 0xcc, 0xcc); // draw checkerboard background for($y=0; $y<480; $y+=40) { for($x=0; $x<640; $x+=80) { $i = $m->add($c); $i->moveTo($x, $y); } $y+=40; for($x=40; $x<640; $x+=80) { $i = $m->add($c); $i->moveTo($x, $y); } } $m->add($s); header('Content-type: application/x-shockwave-flash'); $m->output(); ?>

swfbutton_keypress

(PHP 4 >= 4.0.5)

swfbutton_keypress -- Returns the action flag for keyPress(char)

Description

int swfbutton_keypress ( string str)

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

SWFbutton->addAction

(unknown)

SWFbutton->addAction -- Adds an action

Description

void swfbutton->addaction ( ressource action, int flags)

Varování

swfbutton->addaction() adds the action action to this button for the given conditions. The following flags are valid: SWFBUTTON_MOUSEOVER, SWFBUTTON_MOUSEOUT, SWFBUTTON_MOUSEUP, SWFBUTTON_MOUSEUPOUTSIDE, SWFBUTTON_MOUSEDOWN, SWFBUTTON_DRAGOUT and SWFBUTTON_DRAGOVER.

See also swfbutton->addshape() and SWFAction().

SWFbutton->addShape

(unknown)

SWFbutton->addShape -- Adds a shape to a button

new swfbutton ( void)

Varování

void swfdisplayitem->multcolor ( [int red [, int green [, int blue [, int a]]]])

Varování

swfdisplayitem->multcolor() multiplies the item's color transform by the given values.

The object may be a swfshape(), a swfbutton(), a swftext() or a swfsprite() object. It must have been added using the swfmovie->add().

This simple example will modify your picture's atmospher to Halloween (use a landscape or bright picture).

Příklad 1. swfdisplayitem->multcolor() example

<?php $b = new SWFBitmap("backyard.jpg"); // note use your own picture :-) $s = new SWFShape(); $s->setRightFill($s->addFill($b)); $s->drawLine($b->getWidth(), 0); $s->drawLine(0, $b->getHeight()); $s->drawLine(-$b->getWidth(), 0); $s->drawLine(0, -$b->getHeight()); $m = new SWFMovie(); $m->setDimension($b->getWidth(), $b->getHeight()); $i = $m->add($s); for($n=0; $n<=20; ++$n) { $i->multColor(1.0-$n/10, 1.0, 1.0); $i->addColor(0xff*$n/20, 0, 0); $m->nextFrame(); } header('Content-type: application/x-shockwave-flash'); $m->output(); ?>

SWFDisplayItem->remove

(unknown)

SWFDisplayItem->remove -- Removes the object from the movie

The swffill() object allows you to transform (scale, skew, rotate) bitmap and gradient fills. swffill() objects are created by the swfshape->addfill() methods.

SWFFill has the following methods : swffill->moveto() and swffill->scaleto(), swffill->rotateto(), swffill->skewxto() and swffill->skewyto().

swffont->getwidth

(unknown)

swffont->getwidth -- Returns the string's width

Description

int swffont->getwidth ( string string)

Varování

swffont->getwidth() returns the string string's width, using font's default scaling. You'll probably want to use the SWFText() version of this method which uses the text object's scale.

SWFFont

(PHP 4 >= 4.0.5)

SWFFont -- Loads a font definition

Description

new swffont ( string filename)

Varování

If filename is the name of an FDB file (i.e., it ends in ".fdb"), load the font definition found in said file. Otherwise, create a browser-defined font reference.

FDB ("font definition block") is a very simple wrapper for the SWF DefineFont2 block which contains a full description of a font. One may create FDB files from SWT Generator template files with the included makefdb utility- look in the util directory off the main ming distribution directory.

Browser-defined fonts don't contain any information about the font other than its name. It is assumed that the font definition will be provided by the movie player. The fonts _serif, _sans, and _typewriter should always be available. For example:

<?php $f = newSWFFont("_sans"); ?>
will give you the standard sans-serif font, probably the same as what you'd get with <font name="sans-serif"> in HTML.

swffont() returns a reference to the font definition, for use in the SWFText->setFont() and the SWFTextField->setFont() methods.

SWFFont has the following methods : swffont->getwidth().

SWFGradient->addEntry

(unknown)

SWFGradient->addEntry -- Adds an entry to the gradient list.

Description

void swfgradient->addentry ( float ratio, int red, int green, int blue [, int a])

Varování

swfgradient->addentry() adds an entry to the gradient list. ratio is a number between 0 and 1 indicating where in the gradient this color appears. Thou shalt add entries in order of increasing ratio.

red, green, blue is a color (RGB mode). Last parameter a is optional.

SWFGradient

(PHP 4 >= 4.0.5)

SWFGradient -- Creates a gradient object

Description

new swfgradient ( void)

Varování

swfgradient() creates a new SWFGradient object.

new swfmorph ( void)

Varování

swfmorph() creates a new SWFMorph object.

Also called a "shape tween". This thing lets you make those tacky twisting things that make your computer choke. Oh, joy!

The methods here are sort of weird. It would make more sense to just have newSWFMorph(shape1, shape2);, but as things are now, shape2 needs to know that it's the second part of a morph. (This, because it starts writing its output as soon as it gets drawing commands- if it kept its own description of its shapes and wrote on completion this and some other things would be much easier.)

SWFMorph has the following methods : swfmorph->getshape1() and swfmorph->getshape1().

This simple example will morph a big red square into a smaller blue black-bordered square.

Příklad 1. swfmorph() example

<?php $p = new SWFMorph(); $s = $p->getShape1(); $s->setLine(0,0,0,0); /* Note that this is backwards from normal shapes (left instead of right). I have no idea why, but this seems to work.. */ $s->setLeftFill($s->addFill(0xff, 0, 0)); $s->movePenTo(-1000,-1000); $s->drawLine(2000,0); $s->drawLine(0,2000); $s->drawLine(-2000,0); $s->drawLine(0,-2000); $s = $p->getShape2(); $s->setLine(60,0,0,0); $s->setLeftFill($s->addFill(0, 0, 0xff)); $s->movePenTo(0,-1000); $s->drawLine(1000,1000); $s->drawLine(-1000,1000); $s->drawLine(-1000,-1000); $s->drawLine(1000,-1000); $m = new SWFMovie(); $m->setDimension(3000,2000); $m->setBackground(0xff, 0xff, 0xff); $i = $m->add($p); $i->moveTo(1500,1000); for($r=0.0; $r<=1.0; $r+=0.1) { $i->setRatio($r); $m->nextFrame(); } header('Content-type: application/x-shockwave-flash'); $m->output(); ?>

SWFMovie->add

Varování

swfmovie->streammp3() streams the mp3 file mp3FileName. Not very robust in dealing with oddities (can skip over an initial ID3 tag, but that's about it). Like SWFShape->addJpegFill(), this isn't a stable function- we'll probably need to make a separate SWFSound object to contain sound types.

Note that the movie isn't smart enough to put enough frames in to contain the entire mp3 stream- you'll have to add (length of song * frames per second) frames to get the entire stream in.

Yes, now you can use ming to put that rock and roll devil worship music into your SWF files. Just don't tell the RIAA.

Příklad 1. swfmovie->streammp3() example

<?php $m = new SWFMovie(); $m->setRate(12.0); $m->streamMp3("distortobass.mp3"); // use your own MP3 // 11.85 seconds at 12.0 fps = 142 frames $m->setFrames(142); header('Content-type: application/x-shockwave-flash'); $m->output(); ?>

SWFMovie

(PHP 4 >= 4.0.5)

SWFMovie -- Creates a new movie object, representing an SWF version 4 movie.

Description

new swfmovie ( void)

Varování

swfmovie() creates a new movie object, representing an SWF version 4 movie.

SWFMovie has the following methods : swfmovie->output(),swfmovie->save(), swfmovie->add(), swfmovie->remove(), swfmovie->nextframe(), swfmovie->setbackground(), swfmovie->setrate(), swfmovie->setdimension(), swfmovie->setframes() and swfmovie->streammp3().

See examples in : swfdisplayitem->rotateto(), swfshape->setline(), swfshape->addfill()... Any example will use this object.

SWFShape->addFill

(unknown)

SWFShape->addFill -- Adds a solid fill to the shape.

Description

void swfshape->addfill ( int red, int green, int blue [, int a])

Varování

void swfshape->addfill ( SWFbitmap bitmap [, int flags])

Varování

void swfshape->addfill ( SWFGradient gradient [, int flags])

Varování

swfshape->addfill() adds a solid fill to the shape's list of fill styles. swfshape->addfill() accepts three different types of arguments.

red, green, blue is a color (RGB mode). Last parameter a is optional.

The bitmap argument is an swfbitmap() object. The flags argument can be one of the following values : SWFFILL_CLIPPED_BITMAP or SWFFILL_TILED_BITMAP. Default is SWFFILL_TILED_BITMAP. I think.

void swfshape->setleftfill ( swfgradient fill)

Varování

void swfshape->setleftfill ( int red, int green, int blue [, int a])

Varování

What this nonsense is about is, every edge segment borders at most two fills. When rasterizing the object, it's pretty handy to know what those fills are ahead of time, so the swf format requires these to be specified.

swfshape->setleftfill() sets the fill on the left side of the edge- that is, on the interior if you're defining the outline of the shape in a counter-clockwise fashion. The fill object is an SWFFill object returned from one of the addFill functions above.

This seems to be reversed when you're defining a shape in a morph, though. If your browser crashes, just try setting the fill on the other side.

Shortcut for swfshape->setleftfill($s->addfill($r, $g, $b [, $a]));.

SWFShape->setLine

(unknown)

SWFShape->setLine -- Sets the shape's line style.

Description

void swfshape->setline ( int width [, int red [, int green [, int blue [, int a]]]])

Varování

swfshape->setline() sets the shape's line style. width is the line's width. If width is 0, the line's style is removed (then, all other arguments are ignored). If width > 0, then line's color is set to red, green, blue. Last parameter a is optional.

swfshape->setline() accepts 1, 4 or 5 arguments (not 3 or 2).

You must declare all line styles before you use them (see example).

This simple example will draw a big "!#%*@", in funny colors and gracious style.

Příklad 1. swfshape->setline() example

<?php $s = new SWFShape(); $f1 = $s->addFill(0xff, 0, 0); $f2 = $s->addFill(0xff, 0x7f, 0); $f3 = $s->addFill(0xff, 0xff, 0); $f4 = $s->addFill(0, 0xff, 0); $f5 = $s->addFill(0, 0, 0xff); // bug: have to declare all line styles before you use them $s->setLine(40, 0x7f, 0, 0); $s->setLine(40, 0x7f, 0x3f, 0); $s->setLine(40, 0x7f, 0x7f, 0); $s->setLine(40, 0, 0x7f, 0); $s->setLine(40, 0, 0, 0x7f); $f = new SWFFont('Techno.fdb'); $s->setRightFill($f1); $s->setLine(40, 0x7f, 0, 0); $s->drawGlyph($f, '!'); $s->movePen($f->getWidth('!'), 0); $s->setRightFill($f2); $s->setLine(40, 0x7f, 0x3f, 0); $s->drawGlyph($f, '#'); $s->movePen($f->getWidth('#'), 0); $s->setRightFill($f3); $s->setLine(40, 0x7f, 0x7f, 0); $s->drawGlyph($f, '%'); $s->movePen($f->getWidth('%'), 0); $s->setRightFill($f4); $s->setLine(40, 0, 0x7f, 0); $s->drawGlyph($f, '*'); $s->movePen($f->getWidth('*'), 0); $s->setRightFill($f5); $s->setLine(40, 0, 0, 0x7f); $s->drawGlyph($f, '@'); $m = new SWFMovie(); $m->setDimension(3000,2000); $m->setRate(12.0); $i = $m->add($s); $i->moveTo(1500-$f->getWidth("!#%*@")/2, 1000+$f->getAscent()/2); header('Content-type: application/x-shockwave-flash'); $m->output(); ?>

SWFShape->setRightFill

(unknown)

SWFShape->setRightFill -- Sets right rasterizing color.

Description

void swfshape->setrightfill ( swfgradient fill)

Varování

new swftextfield ( [int flags])

Varování

swftextfield() creates a new text field object. Text Fields are less flexible than swftext() objects- they can't be rotated, scaled non-proportionally, or skewed, but they can be used as form entries, and they can use browser-defined fonts.

The optional flags change the text field's behavior. It has the following possibles values :

SWFTEXTFIELD_DRAWBOX draws the outline of the textfield
SWFTEXTFIELD_HASLENGTH
SWFTEXTFIELD_HTML allows text markup using HTML-tags
SWFTEXTFIELD_MULTILINE allows multiple lines
SWFTEXTFIELD_NOEDIT indicates that the field shouldn't be user-editable
SWFTEXTFIELD_NOSELECT makes the field non-selectable
SWFTEXTFIELD_PASSWORD obscures the data entry
SWFTEXTFIELD_WORDWRAP allows text to wrap

Flags are combined with the bitwise OR operation. For example,

<?php
$t = newSWFTextField(SWFTEXTFIELD_PASSWORD | SWFTEXTFIELD_NOEDIT); 
?>

creates a totally useless non-editable password field.

SWFTextField has the following methods : swftextfield->setfont(), swftextfield->setbounds(), swftextfield->align(), swftextfield->setheight(), swftextfield->setleftmargin(), swftextfield->setrightmargin(), swftextfield->setmargins(), swftextfield->setindentation(), swftextfield->setlinespacing(), swftextfield->setcolor(), swftextfield->setname() and swftextfield->addstring().

LX. Smíšené funkce

Tyto funkce byly umístěny zde, protože nespadají do žádné jiné kategorie.

Obsah
connection_aborted -- Vrací TRUE, pokud se klient odpojil
connection_status -- Vrací bitové pole stavu spojení
connection_timeout -- Return TRUE if script timed out
constant -- Returns the value of a constant
define -- Definuje pojmenovanou konstantu.
defined -- Zkontroluje, jestli existuje daná pojmenovaná konstanta
die -- Vytiskne vzkaz a ukončí současný skript
eval -- Vyhodnotí řetězec jako PHP kód
exit -- Ukončí současný skript
get_browser -- Určuje schopnosti uživatelova browseru
highlight_file -- Zvýrazní syntaxi souboru
highlight_string -- Zvýraznění syntaxe řetězce
ignore_user_abort -- Nastavuje, jestli má ukončení spojení klientem přerušit vykonávání skriptu
leak -- Nenávratně alokuje pamět
pack -- Sbalí data do binárního řetězce.
show_source -- Zvýrazní syntaxi souboru
sleep -- Odloží provedení
uniqid -- Generatuje unikátní id
unpack -- Rozbalí data z binárního řetězce
usleep -- Odloží provedení v mikrosekundách

exit -- Ukončí současný skript

Popis

void exit ( void)

Tento jazykový konstrkut ukončí parsování skriptu. Nevrací žádnou hodnotu.

Viz také die().

get_browser

(PHP 3, PHP 4 )

get_browser -- Určuje schopnosti uživatelova browseru

Popis

object get_browser ( [string user_agent])

get_browser() se pokusí určit schopnosti uživatelova browseru. Toho je dosaženo vyhledáním informací o browseru v souboru browscap.ini. Standardne se použije $HTTP_USER_AGENT; nicméně, můžete to změnit (tj. vyhledat informace o jiném browseru) předáním volitelného argumentu user_agent.

Informace se vracejí jako objekt, který obsahuje různé datové elementy, které reprezentují například hlavní a vedlejší číslo verze a ID řetězec; TRUE/false hodnoty vlastností jako podpora rámců, JavaScript a cookies, atd.

Jakkoli browscap.ini obsahuje informace o mnoha browserech, aktuálnost databáze závisí na uživatelských updatech. Formát souboru je poměrně snadno pochopitelný.

Následující příklad ukazuje, jak by se daly vypsat všechny informace získané o uživatelově browseru.

Příklad 1. get_browser() příklad

<?php function list_array ($array) { while (list ($key, $value) = each ($array)) { $str .= "<b>$key:</b> $value<br>\n"; } return $str; } echo "$HTTP_USER_AGENT<hr>\n"; $browser = get_browser(); echo list_array ((array) $browser); ?>

Výstup z výše uvedeného skriptu by vypadal asi takto:

Mozilla/4.5 [en] (X11; U; Linux 2.2.9 i586)<hr>
<b>browser_name_pattern:</b> Mozilla/4\.5.*<br>
<b>parent:</b> Netscape 4.0<br>
<b>platform:</b> Unknown<br>
<b>majorver:</b> 4<br>
<b>minorver:</b> 5<br>
<b>browser:</b> Netscape<br>
<b>version:</b> 4<br>
<b>frames:</b> 1<br>
<b>tables:</b> 1<br>
<b>cookies:</b> 1<br>
<b>backgroundsounds:</b> <br>
<b>vbscript:</b> <br>
<b>javascript:</b> 1<br>
<b>javaapplets:</b> 1<br>
<b>activexcontrols:</b> <br>
<b>beta:</b> <br>
<b>crawler:</b> <br>
<b>authenticodeupdate:</b> <br>
<b>msn:</b> <br>

Aby to fungovalo, browscap direktiva ve vašem konfiguračním souboru musí ukazovat na platné umístění browscap.ini souboru.

Pro další informace (včetně lokací na kterých můžete získat browscap.ini soubor) viz PHP FAQ na http://www.php.net/FAQ.php.

highlight_file

(PHP 4 )

highlight_file -- Zvýrazní syntaxi souboru

Popis

Nápad na tuto funkci byl převzat z Perlu, a všechny formátovací kódy fungují stejně jako tam, nicméně, některé formátovací kódy chybí, jako například Perlovský formátovací kód "u". Formátovací řetězec sestává z formátovacích kódu následovaných volitelným opakovacím argumentem. Opakovací argument může být buď celočíselná hodnota, nebo * pro opakování do konce vstupních dat. U a, A, h, H počet opakování určuje, kolik znaků se vezme z jednoho datového argumentu, u @ je to absolutní pozice, kde se mají umístit další data, u všeho ostatního počet opakování určuje, kolik datových argumentů se spotřebuje a sbalí do výsledného binárního řetězce. V současnosti jsou implementovány

a řetězec doplněný NUL hodnotami
A řetězec doplněný SPACE hodnotami
h Hex řetězec, spodní slabika první
H Hex řetězec, horní slabika první
c signed char
C unsigned char
s signed short (vždy 16 bitů, machine byte order)
S unsigned short (vždy 16 bitů, machine byte order)
n unsigned short (vždy 16 bitů, big endian byte order)
v unsigned short (vždy 16 bitů, little endian byte order)
i signed integer (velikost a pořadí bytů závislá na systému)
I unsigned integer (velikost a pořadí bytů závislá na systému)
l signed long (vždy 32 bitů, machine byte order)
L unsigned long (vždy 32 bitů, machine byte order)
N unsigned long (vždy 32 bitů, big endian byte order)
V unsigned long (vždy 32 bitů, little endian byte order)
f float (velikost a reprezentace závislá na systému)
d double (velikost a reprezentace závislá na systému)
x NUL byte
X Back up one byte
@ NUL-fill to absolute position

Příklad 1. pack() formátovací řetězec

$binarydata = pack ("nvc*", 0x1234, 0x5678, 65, 66);

Výsledný binární řetězec bude 6 bytů dlouhý, a bude obsahovat bytovou sekvenci 0x12, 0x34, 0x78, 0x56, 0x41, 0x42.

Všimněte si, že rozdíl mezi hodnotami se znaménkem a bez znaménka ovlivňuje pouze funkci unpack(), zatímco funkce pack() dává stejný výsledek pro formátovací kódy se znaménkem i bez znaménka.

Dále si všimněte, že PHP interně ukládá celočíselné hodnoty jako hodnoty se znaménkem o velikosti závislé na systému. Pokud zadáte hodnotu bez znaménka, která bude příliš velká, než aby se dala takto uložit, převede se na double, což často vytváří nežádoucí výsledky.

show_source

(PHP 4 )

show_source -- Zvýrazní syntaxi souboru

Popis

boolean show_source ( string filename)

Funkce show_source() vytiskne barevně zvýrazněnou syntaxi kódu obsaženého ve filename s použitím barev definovaných ve zvýrazňovači syntaxe zabudovaném v PHP. Vrací TRUE při úspěchu, jinak FALSE (PHP 4).

Poznámka: Tato funkce je alias funkce highlight_file()

Viz také highlight_string(), highlight_file().

sleep

(PHP 3, PHP 4 )

sleep -- Odloží provedení

Popis

void sleep ( int seconds)

Funkce sleep odkládá provedení programu o počet sekund předaný v argumentu seconds.

Viz také usleep().

uniqid

(PHP 3, PHP 4 )

uniqid -- Generatuje unikátní id

Popis

int uniqid ( string prefix [, boolean lcg])

uniqid() vrací unikátní identifikátor založený na současném čase v mikrosekundách, opatřený prefixem. Prefix může být užitečný například pokud generujete identifikátory na několika serverech současně, které by mohly vygenerovat identifikátor ve stejnou mikrosekundu. Prefix může být až 114 znaků dlouhý.

Pokud je volitelný argument lcg TRUE, uniqid() přidá dodatečnou "kombinovanou LCG" entropii na konec své návratové hodnoty, což by mělo učinit výsledky ještě unikátnějšími.

Pokud je prefix prázdný, vrácený řetěec bude 13 znaků dlouhý. Pokud je lcg TRUE, bude dlouhý 23 znaků.

Poznámka: lcg argument je přístupný pouze v PHP 4 and PHP 3.0.13 a vyšších.

Pokud potřebujete unikátní identifikátor nebo symbol, a zamýšlíte předat tento symbol uživateli po síti (např. session cookies), doporučujeme použít něco jako

$token = md5 (uniqid ("")); // no random portion
$better_token = md5 (uniqid (rand())); // better, difficult to guess

Toto vytvoří 32znakový identifikátor (128bitové hexa číslo), které se extrémně težko předpovídá.

unpack

(PHP 3, PHP 4 )

unpack -- Rozbalí data z binárního řetězce

Popis

array unpack ( string format, string data)

unpack() rozbalí data z binárního řetězce do pole podle format. Vrací pole obsahující rozbalené prvky binárního řetězce.

unpack() funguje trochu jinak než v Perlu, jelikož rozbalená data jsou uložena v asociativním poli. Toho dosáhnete tak, že vyjmenujete různé formátovací kódy a oddělíte je lomítkem /.

Příklad 1. unpack() format string

$array = unpack ("c2chars/nint", $binarydata);

Výsledné pole obsahuej položky "chars1", "chars2" and "int".

Vysvětlení formátovacích kódů viz také: pack()

Všimněte si, že PHP interně ukládá celočíselné hodnoty se znaménkem. Pokud rozbalíte velkou celočíselnou hodnotu bez znaménka a ta má stejnou velikost jako hodnoty interně ukládané PHP, výsledkem bude negativní číslo, i když bylo zadáno rozbalování bez znaménka.

usleep

(PHP 3, PHP 4 )

usleep -- Odloží provedení v mikrosekundách

Popis

void usleep ( int micro_seconds)

Funkce usleep() odloží provedení skriptu o daný počet micro_seconds.

Viz také sleep().

Poznámka: Tato funkce nefunguje na Windows systémech.

LXI. mnoGoSearch Functions

These functions allow you to access the mnoGoSearch (former UdmSearch) free search engine. In order to have these functions available, you must compile PHP with mnogosearch support by using the --with-mnogosearch option. If you use this option without specifying the path to mnogosearch, PHP will look for mnogosearch under /usr/local/mnogosearch path by default. If you installed mnogosearch at other path you should specify it: --with-mnogosearch=DIR.

mnoGoSearch is a full-featured search engine software for intranet and internet servers, distributed under the GNU license. mnoGoSearch has number of unique features, which makes it appropriate for a wide range of application from search within your site to a specialized search system such as cooking recipes or newspaper search, FTP archive search, news articles search, etc. It offers full-text indexing and searching for HTML, PDF, and text documents. mnoGoSearch consists of two parts. The first is an indexing mechanism (indexer). The purpose of indexer is to walk through HTTP, FTP, NEWS servers or local files, recursively grabbing all the documents and storing meta-data about that documents in a SQL database in a smart and effective manner. After every document is referenced by its corresponding URL, meta-data collected by indexer is used later in a search process. The search is performed via Web interface. C CGI, PHP and Perl search front ends are included.

Poznámka: PHP contains built-in mysql access library, which can be used to access MySQL. It is known that mnoGoSearch is not compatible with this built-in library and can work only with generic MySQL libraries. Thus, if you use mnoGoSearch with mysql, during PHP configuration you have to indicate directory of MySQL installation, that was used during mnoGoSearch configuration, i.e. for example: --with-mnogosearch --with-mysql=/usr.

You need at least version 3.1.10 of mnoGoSearch installed to use these functions.

More information about mnoGoSearch can be found at http://www.mnogosearch.ru/.

Obsah
udm_add_search_limit -- Add various search limits
udm_alloc_agent -- Allocate mnoGoSearch session
udm_api_version -- Get mnoGoSearch API version.
udm_cat_list -- Get all the categories on the same level with the current one.
udm_cat_path -- Get the path to the current category.
udm_check_charset -- Check if the given charset is known to mnogosearch
udm_check_stored -- Check connection to stored
udm_clear_search_limits -- Clear all mnoGoSearch search restrictions
udm_close_stored -- Close connection to stored
udm_crc32 -- Return CRC32 checksum of gived string
udm_errno -- Get mnoGoSearch error number
udm_error -- Get mnoGoSearch error message
udm_find -- Perform search
udm_free_agent -- Free mnoGoSearch session
udm_free_ispell_data -- Free memory allocated for ispell data
udm_free_res -- Free mnoGoSearch result
udm_get_doc_count -- Get total number of documents in database.
udm_get_res_field -- Fetch mnoGoSearch result field
udm_get_res_param -- Get mnoGoSearch result parameters
udm_load_ispell_data -- Load ispell data
udm_open_stored -- Open connection to stored
udm_set_agent_param -- Set mnoGoSearch agent session parameters

udm_add_search_limit

(PHP 4 >= 4.0.5)

udm_add_search_limit -- Add various search limits

Description

int udm_add_search_limit ( int agent, int var, string val)

udm_add_search_limit() returns TRUE on success, FALSE on error. Adds search restrictions.

agent - a link to Agent, received after call to udm_alloc_agent().

var - defines parameter, indicating limit.

val - defines value of the current parameter.

Possible var values:

UDM_LIMIT_URL - defines document URL limitations to limit search through subsection of database. It supports SQL % and _ LIKE wildcards, where % matches any number of characters, even zero characters, and _ matches exactly one character. E.g. http://my.domain.__/catalog may stand for http://my.domain.ru/catalog and http://my.domain.ua/catalog.
UDM_LIMIT_TAG - defines site TAG limitations. In indexer-conf you can assign specific TAGs to various sites and parts of a site. Tags in mnoGoSearch 3.1.x are lines, that may contain metasymbols % and _. Metasymbols allow searching among groups of tags. E.g. there are links with tags ABCD and ABCE, and search restriction is by ABC_ - the search will be made among both of the tags.
UDM_LIMIT_LANG - defines document language limitations.
UDM_LIMIT_CAT - defines document category limitations. Categories are similar to tag feature, but nested. So you can have one category inside another and so on. You have to use two characters for each level. Use a hex number going from 0-F or a 36 base number going from 0-Z. Therefore a top-level category like 'Auto' would be 01. If it has a subcategory like 'Ford', then it would be 01 (the parent category) and then 'Ford' which we will give 01. Put those together and you get 0101. If 'Auto' had another subcategory named 'VW', then it's id would be 01 because it belongs to the 'Ford' category and then 02 because it's the next category. So it's id would be 0102. If VW had a sub category called 'Engine' then it's id would start at 01 again and it would get the 'VW' id 02 and 'Auto' id of 01, making it 010201. If you want to search for sites under that category then you pass it cat=010201 in the url.
UDM_LIMIT_DATE - defines limitation by date document was modified.

Format of parameter value: a string with first character < or >, then with no space - date in unixtime format, for example:

Udm_Add_Search_Limit($udm,UDM_LIMIT_DATE,"<908012006");

If > character is used, then search will be restricted to those documents having modification date greater than entered. If <, then smaller.

udm_alloc_agent

(PHP 4 >= 4.0.5)

udm_alloc_agent -- Allocate mnoGoSearch session

Description

int udm_alloc_agent ( string dbaddr [, string dbmode])

udm_alloc_agent() returns mnogosearch agent identifier on success, FALSE on error. This function creates a session with database parameters.

dbaddr - URL-style database description. Options (type, host, database name, port, user and password) to connect to SQL database. Do not matter for built-in text files support. Format: DBAddr DBType:[//[DBUser[:DBPass]@]DBHost[:DBPort]]/DBName/ Currently supported DBType values are: mysql, pgsql, msql, solid, mssql, oracle, ibase. Actually, it does not matter for native libraries support. But ODBC users should specify one of supported values. If your database type is not supported, you may use "unknown" instead.

dbmode - You may select SQL database mode of words storage. When "single" is specified, all words are stored in the same table. If "multi" is selected, words will be located in different tables depending of their lengths. "multi" mode is usually faster but requires more tables in database. If "crc" mode is selected, mnoGoSearch will store 32 bit integer word IDs calculated by CRC32 algorythm instead of words. This mode requres less disk space and it is faster comparing with "single" and "multi" modes. "crc-multi" uses the same storage structure with the "crc" mode, but also stores words in different tables depending on words lengths like "multi" mode. Format: DBMode single/multi/crc/crc-multi

Poznámka: dbaddr and dbmode must match those used during indexing.

Poznámka: In fact this function does not open connection to database and thus does not check entered login and password. Actual connection to database and login/password verification is done by udm_find().

udm_api_version

(PHP 4 >= 4.0.5)

udm_api_version -- Get mnoGoSearch API version.

Description

int udm_api_version ( void)

udm_api_version() returns mnoGoSearch API version number. E.g. if mnoGoSearch 3.1.10 API is used, this function will return 30110.

This function allows user to identify which API functions are available, e.g. udm_get_doc_count() function is only available in mnoGoSearch 3.1.11 or later.

Example:

if (udm_api_version() >= 30111) {
   print  "Total number of urls in database: ".udm_get_doc_count($udm)."<br>\n";
   }

udm_cat_list

(PHP 4 >= 4.0.6)

udm_cat_list -- Get all the categories on the same level with the current one.

Description

array udm_cat_list ( int agent, string category)

udm_cat_list() returns array listing all categories of the same level as current category in the categories tree.

The function can be useful for developing categories tree browser.

Returns array with the following format:

The array consists of pairs. Elements with even index numbers contain category paths, odd elements contain corresponding category names.

  $array[0] will contain '020300'
  $array[1] will contain 'Audi'
  $array[2] will contain '020301'
  $array[3] will contain 'BMW'
  $array[4] will contain '020302'
  $array[5] will contain 'Opel'
  ...
etc.

Following is an example of displaying links of the current level in format:
  Audi
  BMW
  Opel
  ...

<?php
 $cat_list_arr = udm_cat_list($udm_agent,$cat);
 $cat_list = '';
 for ($i=0; $i<count($cat_list_arr); $i+=2) {
   $path = $cat_list_arr[$i];
   $name = $cat_list_arr[$i+1];
   $cat_list .= "<a href=\"$PHP_SELF?cat=$path\">$name</a><br>";
 }
?>

udm_cat_path

(PHP 4 >= 4.0.6)

udm_cat_path -- Get the path to the current category.

Description

array udm_cat_path ( int agent, string category)

udm_cat_path() returns array describing path in the categories tree from the tree root to the current category.

agent - agent link identifier.

category - current category - the one to get path to.

Returns array with the following format:

The array consists of pairs. Elements with even index numbers contain category paths, odd elements contain corresponding category names.

For example, the call $array=udm_cat_path($agent, '02031D'); may return the following array:

$array[0] will contain ''
$array[1] will contain 'Root'
$array[2] will contain '02'
$array[3] will contain 'Sport'
$array[4] will contain '0203'
$array[5] will contain 'Auto'
$array[4] will contain '02031D'
$array[5] will contain 'Ferrari'

Příklad 1. Specifying path to the current category in the following format: '> Root > Sport > Auto > Ferrari'

<?php
  $cat_path_arr = udm_cat_path($udm_agent,$cat);
  $cat_path = '';
  for ($i=0; $i<count($cat_path_arr); $i+=2) {
    $path = $cat_path_arr[$i];
    $name = $cat_path_arr[$i+1];
    $cat_path .= " > <a href=\"$PHP_SELF?cat=$path\">$name</a> ";
  }
?>

udm_error

(PHP 4 >= 4.0.5)

udm_error -- Get mnoGoSearch error message

Description

string udm_error ( int agent)

udm_error() returns mnoGoSearch error message, empty string if no error.

agent - link to agent identifier, received after call to udm_alloc_agent().

Receiving agent error message.

udm_find

(PHP 4 >= 4.0.5)

udm_find -- Perform search

Description

int udm_find ( int agent, string query)

udm_find() returns result link identifier on success, FALSE on error.

The search itself. The first argument - session, the next one - query itself. To find something just type words you want to find and press SUBMIT button. For example, "mysql odbc". You should not use quotes " in query, they are written here only to divide a query from other text. mnoGoSearch will find all documents that contain word "mysql" and/or word "odbc". Best documents having bigger weights will be displayed first. If you use search mode ALL, search will return documents that contain both (or more) words you entered. In case you use mode ANY, the search will return list of documents that contain any of the words you entered. If you want more advanced results you may use query language. You should select "bool" match mode in the search from.

mnoGoSearch understands the following boolean operators:

string udm_get_res_field ( int res, int row, int field)

udm_get_res_field() returns result field value on success, FALSE on error.

res - a link to result identifier, received after call to udm_find().

row - the number of the link on the current page. May have values from 0 to UDM_PARAM_NUM_ROWS-1.

field - field identifier, may have the following values:

UDM_FIELD_URL - document URL field
UDM_FIELD_CONTENT - document Content-type field (for example, text/html).
UDM_FIELD_CATEGORY - document category field. Use udm_cat_path() to get full path to current category from the categories tree root. (This parameter is available only in PHP 4.0.6 or later).
UDM_FIELD_TITLE - document title field.
UDM_FIELD_KEYWORDS - document keywords field (from META KEYWORDS tag).
UDM_FIELD_DESC - document description field (from META DESCRIPTION tag).
UDM_FIELD_TEXT - document body text (the first couple of lines to give an idea of what the document is about).
UDM_FIELD_SIZE - document size.
UDM_FIELD_URLID - unique URL ID of the link.
UDM_FIELD_RATING - page rating (as calculated by mnoGoSearch).
UDM_FIELD_MODIFIED - last-modified field in unixtime format.
UDM_FIELD_ORDER - the number of the current document in set of found documents.
UDM_FIELD_CRC - document CRC.

udm_get_res_param

(PHP 4 >= 4.0.5)

udm_get_res_param -- Get mnoGoSearch result parameters

Description

string udm_get_res_param ( int res, int param)

udm_get_res_param() returns result parameter value on success, FALSE on error.

res - a link to result identifier, received after call to udm_find().

param - parameter identifier, may have the following values:

UDM_PARAM_NUM_ROWS - number of received found links on the current page. It is equal to UDM_PARAM_PAGE_SIZE for all search pages, on the last page - the rest of links.
UDM_PARAM_FOUND - total number of results matching the query.
UDM_PARAM_WORDINFO - information on the words found. E.g. search for "a good book" will return "a: stopword, good:5637, book: 120"
UDM_PARAM_SEARCHTIME - search time in seconds.
UDM_PARAM_FIRST_DOC - the number of the first document displayed on current page.
UDM_PARAM_LAST_DOC - the number of the last document displayed on current page.

udm_load_ispell_data

(PHP 4 >= 4.0.5)

udm_load_ispell_data -- Load ispell data

Description

int udm_load_ispell_data ( int agent, int var, string val1, string val2, int flag)

udm_load_ispell_data() loads ispell data. Returns TRUE on success, FALSE on error.

agent - agent link identifier, received after call to udm_alloc_agent().

var - parameter, indicating the source for ispell data. May have the following values:

After using this function to free memory allocated for ispell data, please use udm_free_ispell_data(), even if you use UDM_ISPELL_TYPE_SERVER mode.

The fastest mode is UDM_ISPELL_TYPE_SERVER. UDM_ISPELL_TYPE_TEXT is slower and UDM_ISPELL_TYPE_DB is the slowest. The above pattern is TRUE for mnoGoSearch 3.1.10 - 3.1.11. It is planned to speed up DB mode in future versions and it is going to be faster than TEXT mode.

UDM_ISPELL_TYPE_DB - indicates that ispell data should be loaded from SQL. In this case, parameters val1 and val2 are ignored and should be left blank. flag should be equal to 1.

Poznámka: flag indicates that after loading ispell data from defined source it sould be sorted (it is necessary for correct functioning of ispell). In case of loading ispell data from files there may be several calls to udm_load_ispell_data(), and there is no sense to sort data after every call, but only after the last one. Since in db mode all the data is loaded by one call, this parameter should have the value 1. In this mode in case of error, e.g. if ispell tables are absent, the function will return FALSE and code and error message will be accessible through udm_error() and udm_errno().

Example:
if (! udm_load_ispell_data($udm,UDM_ISPELL_TYPE_DB,'','',1)) { printf("Error #%d: '%s'\n", udm_errno($udm), udm_error($udm)); exit; }

UDM_ISPELL_TYPE_AFFIX - indicates that ispell data should be loaded from file and initiates loading affixes file. In this case val1 defines double letter language code for which affixes are loaded, and val2 - file path. Please note, that if a relative path entered, the module looks for the file not in UDM_CONF_DIR, but in relation to current path, i.e. to the path where the script is executed. In case of error in this mode, e.g. if file is absent, the function will return FALSE, and an error message will be displayed. Error message text cannot be accessed through udm_error() and udm_errno(), since those functions can only return messages associated with SQL. Please, see flag parameter description in UDM_ISPELL_TYPE_DB.

Example:

if ((! udm_load_ispell_data($udm,UDM_ISPELL_TYPE_AFFIX,'en','/opt/ispell/en.aff',0)) ||
        (! udm_load_ispell_data($udm,UDM_ISPELL_TYPE_AFFIX,'ru','/opt/ispell/ru.aff',0)) ||
        (! udm_load_ispell_data($udm,UDM_ISPELL_TYPE_SPELL,'en','/opt/ispell/en.dict',0)) ||
        (! udm_load_ispell_data($udm,UDM_ISPELL_TYPE_SPELL,'ru','/opt/ispell/ru.dict',1))) {
     exit;
     }

Poznámka: flag is equal to 1 only in the last call.

UDM_ISPELL_TYPE_SPELL - indicates that ispell data should be loaded from file and initiates loading of ispell dictionary file. In this case val1 defines double letter language code for which affixes are loaded, and val2 - file path. Please note, that if a relative path entered, the module looks for the file not in UDM_CONF_DIR, but in relation to current path, i.e. to the path where the script is executed. In case of error in this mode, e.g. if file is absent, the function will return FALSE, and an error message will be displayed. Error message text cannot be accessed through udm_error() and udm_errno(), since those functions can only return messages associated with SQL. Please, see flag parameter description in UDM_ISPELL_TYPE_DB.

if ((! Udm_Load_Ispell_Data($udm,UDM_ISPELL_TYPE_AFFIX,'en','/opt/ispell/en.aff',0)) ||
        (! Udm_Load_Ispell_Data($udm,UDM_ISPELL_TYPE_AFFIX,'ru','/opt/ispell/ru.aff',0)) ||
        (! Udm_Load_Ispell_Data($udm,UDM_ISPELL_TYPE_SPELL,'en','/opt/ispell/en.dict',0)) ||
        (! Udm_Load_Ispell_Data($udm,UDM_ISPELL_TYPE_SPELL,'ru','/opt/ispell/ru.dict',1))) {
      exit;
      }

Poznámka: flag is equal to 1 only in the last call.

UDM_ISPELL_TYPE_SERVER - enables spell server support. val1 parameter indicates address of the host running spell server. val2 ` is not used yet, but in future releases it is going to indicate number of port used by spell server. flag parameter in this case is not needed since ispell data is stored on spellserver already sorted.

Spelld server reads spell-data from a separate configuration file (/usr/local/mnogosearch/etc/spelld.conf by default), sorts it and stores in memory. With clients server communicates in two ways: to indexer all the data is transferred (so that indexer starts faster), from search.cgi server receives word to normalize and then passes over to client (search.cgi) list of normalized word forms. This allows fastest, compared to db and text modes processing of search queries (by omitting loading and sorting all the spell data).

udm_load_ispell_data() function in UDM_ISPELL_TYPE_SERVER mode does not actually load ispell data, but only defines server address. In fact, server is automatically used by udm_find() function when performing search. In case of errors, e.g. if spellserver is not running or invalid host indicated, there are no messages returned and ispell conversion does not work.

Poznámka: This function is available in mnoGoSearch 3.1.12 or later.

Example:
if (!udm_load_ispell_data($udm,UDM_ISPELL_TYPE_SERVER,'','',1)) { printf("Error loading ispell data from server<br>\n"); exit; }

udm_open_stored

(PHP 4 >= 4.2.0)

udm_open_stored -- Open connection to stored

Description

int udm_open_stored ( int agent, string storedaddr)

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

udm_set_agent_param

(PHP 4 >= 4.0.5)

udm_set_agent_param -- Set mnoGoSearch agent session parameters

Description

int udm_set_agent_param ( int agent, int var, string val)

udm_set_agent_param() returns TRUE on success, FALSE on error. Defines mnoGoSearch session parameters.

The following parameters and their values are available:

UDM_PARAM_PAGE_NUM - used to choose search results page number (results are returned by pages beginning from 0, with UDM_PARAM_PAGE_SIZE results per page).
UDM_PARAM_PAGE_SIZE - number of search results displayed on one page.
UDM_PARAM_SEARCH_MODE - search mode. The following values available: UDM_MODE_ALL - search for all words; UDM_MODE_ANY - search for any word; UDM_MODE_PHRASE - phrase search; UDM_MODE_BOOL - boolean search. See udm_find() for details on boolean search.
UDM_PARAM_CACHE_MODE - turns on or off search result cache mode. When enabled, the search engine will store search results to disk. In case a similar search is performed later, the engine will take results from the cache for faster performance. Available values: UDM_CACHE_ENABLED, UDM_CACHE_DISABLED.
UDM_PARAM_TRACK_MODE - turns on or off trackquery mode. Since version 3.1.2 mnoGoSearch has a query tracking support. Note that tracking is implemented in SQL version only and not available in built-in database. To use tracking, you have to create tables for tracking support. For MySQL, use create/mysql/track.txt. When doing a search, front-end uses those tables to store query words, a number of found documents and current UNIX timestamp in seconds. Available values: UDM_TRACK_ENABLED, UDM_TRACK_DISABLED.
UDM_PARAM_PHRASE_MODE - defines whether index database using phrases ("phrase" parameter in indexer.conf). Possible values: UDM_PHRASE_ENABLED and UDM_PHRASE_DISABLED. Please note, that if phrase search is enabled (UDM_PHRASE_ENABLED), it is still possible to do search in any mode (ANY, ALL, BOOL or PHRASE). In 3.1.10 version of mnoGoSearch phrase search is supported only in sql and built-in database modes, while beginning with 3.1.11 phrases are supported in cachemode as well.

Examples of phrase search:

"Arizona desert" - This query returns all indexed documents that contain "Arizona desert" as a phrase. Notice that you need to put double quotes around the phrase
UDM_PARAM_CHARSET - defines local charset. Available values: set of charsets supported by mnoGoSearch, e.g. koi8-r, cp1251, ...
UDM_PARAM_STOPFILE - Defines name and path to stopwords file. (There is a small difference with mnoGoSearch - while in mnoGoSearch if relative path or no path entered, it looks for this file in relation to UDM_CONF_DIR, the module looks for the file in relation to current path, i.e. to the path where the php script is executed.)
UDM_PARAM_STOPTABLE - Load stop words from the given SQL table. You may use several StopwordTable commands. This command has no effect when compiled without SQL database support.
UDM_PARAM_WEIGHT_FACTOR - represents weight factors for specific document parts. Currently body, title, keywords, description, url are supported. To activate this feature please use degrees of 2 in *Weight commands of the indexer.conf. Let's imagine that we have these weights:

  URLWeight     1
  BodyWeight    2
  TitleWeight   4
  KeywordWeight 8
  DescWeight    16


As far as indexer uses bit OR operation for word weights when some word presents several time in the same document, it is possible at search time to detect word appearance in different document parts. Word which appears only in the body will have 00000010 argegate weight (in binary notation). Word used in all document parts will have 00011111 aggregate weight.

This parameter's value is a string of hex digits ABCDE. Each digit is a factor for corresponding bit in word weight. For the given above weights configuration:

   E is a factor for weight 1  (URL Weight bit)
   D is a factor for weight 2  (BodyWeight bit)
   C is a factor for weight 4  (TitleWeight bit)
   B is a factor for weight 8  (KeywordWeight bit)
   A is a factor for weight 16 (DescWeight bit)


Examples:

UDM_PARAM_WEIGHT_FACTOR=00001 will search through URLs only.

UDM_PARAM_WEIGHT_FACTOR=00100 will search through Titles only.

UDM_PARAM_WEIGHT_FACTOR=11100 will search through Title,Keywords,Description but not through URL and Body.

UDM_PARAM_WEIGHT_FACTOR=F9421 will search through:

    Description with factor 15  (F hex)
    Keywords with factor 9
    Title with factor  4
    Body with factor 2
    URL with factor 1


If UDM_PARAM_WEIGHT_FACTOR variable is ommited, original weight value is taken to sort results. For a given above weight configuration it means that document description has a most big weight 16.
UDM_PARAM_WORD_MATCH - word match. You may use this parameter to choose word match type. This feature works only in "single" and "multi" modes using SQL based and built-in database. It does not work in cachemode and other modes since they use word CRC and do not support substring search. Available values:

UDM_MATCH_BEGIN - word beginning match;

UDM_MATCH_END - word ending match;

UDM_MATCH_WORD - whole word match;

UDM_MATCH_SUBSTR - word substring match.
UDM_PARAM_MIN_WORD_LEN - defines minimal word length. Any word shorter this limit is considered to be a stopword. Please note that this parameter value is inclusive, i.e. if UDM_PARAM_MIN_WORD_LEN=3, a word 3 characters long will not be considered a stopword, while a word 2 characters long will be. Default value is 1.
UDM_PARAM_ISPELL_PREFIXES - Possible values: UDM_PREFIXES_ENABLED and UDM_PREFIXES_DISABLED, that respectively enable or disable using prefixes. E.g. if a word "tested" is in search query, also words like "test", "testing", etc. Only suffixes are supported by default. Prefixes usually change word meanings, for example if somebody is searching for the word "tested" one hardly wants "untested" to be found. Prefixes support may also be found useful for site's spelling checking purposes. In order to enable ispell, you have to load ispell data with udm_load_ispell_data().
UDM_PARAM_CROSS_WORDS - enables or disables crosswords support. Possible values: UDM_CROSS_WORDS_ENABLED and UDM_CROSS_WORDS_DISABLED.

The corsswords feature allows to assign words between <a href="xxx"> and </a> also to a document this link leads to. It works in SQL database mode and is not supported in built-in database and Cachemode.

Poznámka: Crosswords are supported only in mnoGoSearch 3.1.11 or later.
UDM_PARAM_VARDIR - specifies a custom path to directory where indexer stores data when using built-in database and in cache mode. By default /var directory of mnoGoSearch installation is used. Can have only string values. The parameter is available in PHP 4.1.0 or later.
UDM_PARAM_VARDIR - specifies a custom path to directory where indexer stores data when using built-in database and in cache mode. By default /var directory of mnoGoSearch installation is used. Can have only string values. The parameter is available in PHP 4.1.0 or later.

LXII. mSQL functions

These functions allow you to access mSQL database servers. In order to have these functions available, you must compile PHP with msql support by using the --with-msql[=dir] option. The default location is /usr/local/Hughes.

More information about mSQL can be found at http://www.hughes.com.au/.

Obsah
msql_affected_rows -- Returns number of affected rows
msql_close -- Close mSQL connection
msql_connect -- Open mSQL connection
msql_create_db -- Create mSQL database
msql_createdb -- Create mSQL database
msql_data_seek -- Move internal row pointer
msql_dbname -- Get current mSQL database name
msql_drop_db -- Drop (delete) mSQL database
msql_dropdb -- Drop (delete) mSQL database
msql_error -- Returns error message of last msql call
msql_fetch_array -- Fetch row as array
msql_fetch_field -- Get field information
msql_fetch_object -- Fetch row as object
msql_fetch_row -- Get row as enumerated array
msql_field_seek -- Set field offset
msql_fieldflags -- Get field flags
msql_fieldlen -- Get field length
msql_fieldname -- Get field name
msql_fieldtable -- Get table name for field
msql_fieldtype -- Get field type
msql_free_result -- Free result memory
msql_freeresult -- Free result memory
msql_list_dbs -- List mSQL databases on server
msql_list_fields -- List result fields
msql_list_tables -- List tables in an mSQL database
msql_listdbs -- List mSQL databases on server
msql_listfields -- List result fields
msql_listtables -- List tables in an mSQL database
msql_num_fields -- Get number of fields in result
msql_num_rows -- Get number of rows in result
msql_numfields -- Get number of fields in result
msql_numrows -- Get number of rows in result
msql_pconnect -- Open persistent mSQL connection
msql_query -- Send mSQL query
msql_regcase -- Make regular expression for case insensitive match
msql_result -- Get result data
msql_select_db -- Select mSQL database
msql_selectdb -- Select mSQL database
msql_tablename -- Get table name of field
msql -- Send mSQL query

msql_affected_rows

(PHP 3>= 3.0.6, PHP 4 )

msql_affected_rows -- Returns number of affected rows

Description

int msql_affected_rows ( int query_identifier)

Returns number of affected ("touched") rows by a specific query (i.e. the number of rows returned by a SELECT, the number of rows modified by an update, or the number of rows removed by a delete).

msql_close

(PHP 3, PHP 4 )

msql_close -- Close mSQL connection

Description

int msql_close ( int link_identifier)

Returns TRUE on success, FALSE on error.

msql_close() closes the link to a mSQL database that's associated with the specified link identifier. If the link identifier isn't specified, the last opened link is assumed.

Note that this isn't usually necessary, as non-persistent open links are automatically closed at the end of the script's execution.

msql_dbname

(PHP 3, PHP 4 )

msql_dbname -- Get current mSQL database name

Description

string msql_dbname ( int query_identifier, int i)

msql_dbname() returns the database name stored in position i of the result pointer returned from the msql_listdbs() function. The msql_numrows() function can be used to determine how many database names are available.

msql_drop_db

(PHP 3, PHP 4 )

msql_drop_db -- Drop (delete) mSQL database

Description

int msql_drop_db ( string database_name, int link_identifier)

Vrací TRUE při úspěchu, FALSE při selhání.

msql_drop_db() attempts to drop (remove) an entire database from the server associated with the specified link identifier.

msql_dropdb

(PHP 3, PHP 4 )

msql_dropdb -- Drop (delete) mSQL database

Description

See msql_drop_db().

msql_error

(PHP 3, PHP 4 )

msql_error -- Returns error message of last msql call

Description

string msql_error ( [int link_identifier])

Errors coming back from the mSQL database backend no longer issue warnings. Instead, use these functions to retrieve the error string.

msql_fetch_array

(PHP 3, PHP 4 )

msql_fetch_array -- Fetch row as array

Description

int msql_fetch_array ( int query_identifier [, int result_type])

Returns an array that corresponds to the fetched row, or FALSE if there are no more rows.

int msql_pconnect ( [string server [, string username [, string password]]])

Returns a positive mSQL persistent link identifier on success, or FALSE on error.

msql_pconnect() acts very much like msql_connect() with two major differences.

First, when connecting, the function would first try to find a (persistent) link that's already open with the same host. If one is found, an identifier for it will be returned instead of opening a new connection.

Second, the connection to the SQL server will not be closed when the execution of the script ends. Instead, the link will remain open for future use (msql_close() will not close links established by msql_pconnect()).

This type of links is therefore called 'persistent'.

msql_query

(PHP 3, PHP 4 )

msql_query -- Send mSQL query

Description

int msql_query ( string query, int link_identifier)

msql_query() sends a query to the currently active database on the server that's associated with the specified link identifier. If the link identifier isn't specified, the last opened link is assumed. If no link is open, the function tries to establish a link as if msql_connect() was called, and use it.

Returns a positive mSQL query identifier on success, or FALSE on error.

Příklad 1. msql_query()

<?php 
$link = msql_connect("dbserver")
   or die("unable to connect to msql server: ".msql_error());
msql_select_db("db", $link)
   or die("unable to select database 'db': ".msql_error());

$result = msql_query("SELECT * FROM table WHERE id=1", $link);
if (!$result) {
   die("query failed: ".msql_error());
}

while ($row = msql_fetch_array($result)) {
    echo $row["id"];
}
?>

msql_regcase

(PHP 3, PHP 4 )

msql_regcase -- Make regular expression for case insensitive match

Description

See sql_regcase().

msql_result

(PHP 3, PHP 4 )

msql_result -- Get result data

Description

int msql_result ( int query_identifier, int i, mixed field)

(PHP 3, PHP 4 )

msql -- Send mSQL query

Description

int msql ( string database, string query, int link_identifier)

Returns a positive mSQL query identifier to the query result, or FALSE on error.

msql() selects a database and executes a query on it. If the optional link identifier isn't specified, the function will try to find an open link to the mSQL server and if no such link is found it'll try to create one as if msql_connect() was called with no arguments (see msql_connect()).

LXIII. MySQL Funkce

Tyto funkce zprostředkovávají přístup na MySQL databázový server. Více informací o MySQL lze nalézt na http://www.mysql.com/.

Dokumentace k MySQL je dostupná na http://www.mysql.com/documentation/.

Požadavky

Aby byly tyto funkce dostupné, musí být PHP zkompilováno s podporou MySQL.

Instalace

Tyto funkce zprostředkovávají přístup na MySQL databázový server. Mají-li být tyto funkce dostupné, musí být PHP zkompilováno s podporou MySQL parametrem --with-mysql. Pokud použijete tento parametr bez zadané cesty k MySQL, PHP použije vestavěné MySQL klient knihovny. Uživatelé, kteří spouští další aplikace používající MySQL (např.: spuštěné PHP3 a PHP4 jako vzájemné moduly v apache či auth-mysql) by měli vždy zadat cestu k MySQL: --with-mysql=/cesta/k/mysql. PHP tak použije klientské knihovny instalované MySQL, čímž se vyvarujete možných konfliktům.

Runtime konfigurace

Chování funkcí MySQL je ovlivněno nastavením v globálním konfiguračním souboru php.ini.

Tabulka 1. Možnosti nastavení MySQL

Jméno	Výchozí	Změnitelné
mysql.allow_persistent	"On"	PHP_INI_SYSTEM
mysql.max_persistent	"-1"	PHP_INI_SYSTEM
mysql.max_links	"-1"	PHP_INI_SYSTEM
mysql.default_port	NULL	PHP_INI_ALL
mysql.default_socket	NULL	PHP_INI_ALL
mysql.default_host	NULL	PHP_INI_ALL
mysql.default_user	NULL	PHP_INI_ALL
mysql.default_password	NULL	PHP_INI_ALL

Podrobný popis a definice konstant PHP_INI_* naleznete v ini_set().

Zde je krátké vysvětlení konfiguračních příkazů.

mysql.allow_persistent boolean: Má-li být povoleno persistentní (trvalá) spojení s MySQL.
mysql.max_persistent integer: Maximální počet persistentních spojení na jeden proces.
mysql.max_links integer: Maximální počet spojení s MySQL na jeden proces včetně persistentních spojení.
mysql.default_port string: Číslo výchozího TCP portu pro spojení s databázovým serverem, pokud není port zadán. Není-li výchozí port zadán, použije se port uvedený v proměnné prostředí MYSQL_TCP_PORT., záznam mysql-tcp v /etc/services nebo "compile-time" konstanta MYSQL_PORT, v tomto pořadí. Win32 používá pouze konstantu MYSQL_PORT.
mysql.default_socket string: Výchozí jméno socketu pro připojení k lokálnímu databázovému serveru, není-li jiný socket specifikován.
mysql.default_host string: Výchozí server pro spojení s databázovým serverem, není-li uveden jiný. Nelze použít při bezpečném režimu (safe mode).
mysql.default_user string: Výchozí uživatel pro spojení s databázovým serverem, není-li uveden jiný uživatel. Nelze použít při bezpečném režimu (safe mode).
mysql.default_password string: Výchozí heslo pro spojení s databázovým serverem, není-li uveeno jiné heslo. Nelze použít při bezpečném režimu (safe mode).

Typy zdrojů

V modulu MySQL jsou použity dva typy zdrojů. První zdroj je identifikátor databázového spojení a druhý, který vykonává výsledek dotazu.

Předdefinované konstanty

Funkce mysql_fetch_array() používá konstanty pro různé typy výsledkových polí. Jsou definovány následující konstanty:

Tabulka 2. MySQL fetch konstanty

konstanta	popis
MYSQL_ASSOC	Sloupce jsou vraceny do pole jehož klíčemi jsou názvy sloupců.
MYSQL_BOTH	Sloupce jsou vráceny do pole majícího číslené i textové klíče, určující pořadí sloupce v tabulce, respektive jeho jméno.
MYSQL_NUM	Vrací sloupec do pole s číselnými klíči reprezentujícími pořadí sloupce v tabulce. První sloupec tabulky začíná klíčem 0.
MYSQL_STORE_RESULT	Určuje, zda by měl být výsledek MySQL bufferován.
MYSQL_USE_RESULT	Určuje, zda by výsledek MySQL neměl být bufferován.

Examples

Zde je jednoduchý ukázkový příklad jak se připojit, provést dotaz, zobrazit výsledné řádky a odpojit se z MySQL databáze.

Příklad 1. Ukázkový příklad použití MySQL

<?php // Připojení, výběr databáze $link = mysql_connect("mysql_host", "mysql_login", "mysql_heslo") or die("Nelze se připojit"); print "Připojeno úspěšně!"; mysql_select_db("moje_databaze") or die("Nelze vybrat databázi"); // Příprava SQL dotazu $query = "SELECT * FROM moje_tabulka"; $result = mysql_query($query) or die("Dotaz nelze provést"); // Zobrazení výsledku v HTML print "<table>\n"; while ($line = mysql_fetch_array($result, MYSQL_ASSOC)) { print "\t<tr>\n"; foreach ($line as $col_value) { print "\t\t<td>$col_value</td>\n"; } print "\t</tr>\n"; } print "</table>\n"; // Odpojení z MySQL databáze mysql_close($link); ?>

Obsah
mysql_affected_rows -- Vrátí počet ovlivněných (změněných) záznamů v MySQL po posledním dotazu
mysql_change_user -- Změní přihlášeného uživatele v současném spojení
mysql_character_set_name -- Vrací jméno znakové stránky
mysql_close -- Ukončí (zavře) MySQL spojení
mysql_connect -- Vytvoří spojení s MySQL Serverem
mysql_create_db -- Vytvoří MySQL databázi
mysql_data_seek -- Přesune ukazatel na aktuální záznam
mysql_db_name -- Vrátí seznam všech databází
mysql_db_query -- Provede MySQL dotaz
mysql_drop_db -- Vymaže (odstraní) MySQL databázi
mysql_errno -- Vrátí číslenou hodnotu chybové hlášky předchozího MySQL příkazu.
mysql_error -- Vrátí text chybové zprávy předchozího MySQL příkazu.
mysql_escape_string -- Upraví řetězec pro bezpečné použití v mysql_query.
mysql_fetch_array -- Načte výsledný řádek do asociativního, čísleného pole nebo obojího.
mysql_fetch_assoc -- Načte výsledný řádek do asociativního pole
mysql_fetch_field -- Načte informace o sloupci z výsledku do proměnné objektu
mysql_fetch_lengths -- Zjistí délku všech položek aktuálního výstupu
mysql_fetch_object -- Načte výsledný záznam do proměnné objektu
mysql_fetch_row -- Načte výsledný záznam do pole
mysql_field_flags -- Načte příznaky sloupce tabulky
mysql_field_len -- Vrací délku sloupce tabulky
mysql_field_name -- Načte název sloupce tabulky
mysql_field_seek -- Nastaví ukazatel na zadaný sloupec
mysql_field_table -- Zjistí jméno tabulky, v níž se nachází uvedený sloupec
mysql_field_type -- Zjistí typ sloupce
mysql_free_result -- Uvolní výsledek z paměti
mysql_get_client_info -- Načte verzi klientské knihovny MySQL
mysql_get_host_info -- Načte informaci o hostu
mysql_get_proto_info -- Načte informaci o protokolu MySQL
mysql_get_server_info -- Načte informace o serveru MySQL
mysql_info -- Vrací informace o posledním dotazu
mysql_insert_id -- Vrací generovanou hodnotu id posledního příkazu INSERT
mysql_list_dbs -- Načte všechny dostupné databáze na MySQL serveru
mysql_list_fields -- Načte výsledek s obsahem sloupce
mysql_list_processes -- List MySQL processes
mysql_list_tables -- Načte všechny tabulky v MySQL databázi
mysql_num_fields -- Vrací počet sloupců ve výsledku
mysql_num_rows -- Vrací počet záznamů ve výsledku
mysql_pconnect -- Otevře persistentní spojení s MySQL serverem
mysql_ping -- Ověří spojení se serverem, případně, není-li spojení dostupné, pokusí se připojit znovu.
mysql_query -- Pošle MySQL dotaz
mysql_real_escape_string -- Upraví řetězec pro bezpečné použití v mysql_query.
mysql_result -- Načte obsah jednoho sloupce tabulky
mysql_select_db -- Nastaví MySQL databázi
mysql_stat -- Vrací aktuální stav systému
mysql_tablename -- Načte jméno tabulky
mysql_thread_id -- Vrátí id aktuálního vlákna
mysql_unbuffered_query -- Pošle SQL dotaz bez načtení a bufferování výsledných záznamů

mysql_affected_rows

(PHP 3, PHP 4 )

mysql_affected_rows -- Vrátí počet ovlivněných (změněných) záznamů v MySQL po posledním dotazu

Popis

int mysql_affected_rows ( [resource spojeni])

mysql_affected_rows() vrátí počet záznamů ovlivněných posledním použitím dotazu INSERT, UPDATE nebo DELETE, kterému odpovídá spojeni. Není-li identifikátor spojení uveden, použije se poslední spojení otevřené pomocí mysql_connect().

Poznámka: Používáte-li transakce, je nutné mysql_affected_rows() volat až po dotazu INSERT, UPDATE nebo DELETE, nikoli hned po potvrzení transakce.

Byl-li poslední dotaz DELETE bez části WHERE, budou smázany všechny záznamy z tabulky, ale tato funce vrátí nulu.

Poznámka: Při použití UPDATE, MySQL neuloží sloupce, ve kterých je nová hodnota shodná s původní. Toto může způsobit, že mysql_affected_rows() nemusí vždy přesně souhlasit se skutečným počtem ovlivněných řádků.

mysql_affected_rows() nelze použít s dotazy SELECT, ale jen s takovými, které mění záznamy. K zjištění počtu řádků vrácených dotazem SELECT použijte funkci mysql_num_rows().

Je-li poslední dotaz chybný, funkce vrátí -1.

Příklad 1. Dotaz typu DELETE (mazání)

<?php /* připojení k databázi */ mysql_pconnect("localhost", "mysql_uziv", "mysql_heslo") or die ("Nelze se připojit"); /* tohle vrátí správný počet smazaných záznamů */ mysql_query("DELETE FROM moje_tabulka WHERE id < 10"); printf ("Smazáno záznamů: %d\n", mysql_affected_rows()); /* bez použití klauzule where v dotazu typu DELETE, bude vrácena 0 */ mysql_query("DELETE FROM moje_tabulka"); printf ("Smazáno záznamů: %d\n", mysql_affected_rows()); ?>

Předchozí příklad by měl následující výstup:

Smazáno záznamů: 10 Smazáno záznamů: 0

Příklad 2. Dotaz typu UPDATE (změna)

<?php /* připojení k databázi */ mysql_pconnect("localhost", "mysql_uziv", "mysql_heslo") or die ("Nelze se připojit"); /* Změna záznamů */ mysql_query("UPDATE moje_tabulka SET used=1 WHERE id < 10"); printf ("Změněno záznamů: %d\n", mysql_affected_rows()); mysql_query("COMMIT"); ?>

Předchozí příklad by měl následující výstup:

Změněno záznamů: 10

Dále také: mysql_num_rows(), mysql_info().

mysql_change_user

(PHP 3>= 3.0.13)

mysql_change_user -- Změní přihlášeného uživatele v současném spojení

Popis

int mysql_change_user ( string uzivatel, string heslo [, string databaze [, resource spojeni]])

mysql_change_user() změní přihlášeného uživatele současného aktivního spojení nebo spojení definované nepovinným parametrem spojeni. Je-li uveden parameter databaze nastaví se tato databáze jako výchozí, v opačném případě zůstane aktivní současná databáze definovaná ve změněném spojení. Vrací TRUE při úspěchu, FALSE při selhání.

Poznámka: Tato funkce byla přidána v PHP 3.0.13 a vyžaduje použití MySQL 3.23.3 nebo vyšší. Není dostupná v PHP 4.

mysql_character_set_name

(PHP 4 CVS only)

mysql_character_set_name -- Vrací jméno znakové stránky

Description

int mysql_character_set_name ( [resource spojeni])

mysql_character_set_name() vrací jméno výchozí znakové stránky aktuálního spojení.

Příklad 1. mysql_character_set_name() příklad

<?php
$link = mysql_connect('localhost', 'mysql_jmeno', 'mysql_heslo');
$charset = mysql_character_set_name($link);
printf ("aktuální znaková stránka je %s\n", $charset);
?>

Předchozí příklad by mohl mít následující výstup:

latin1

Dále také: mysql_real_escape_string()

mysql_close

(PHP 3, PHP 4 )

mysql_close -- Ukončí (zavře) MySQL spojení

Popis

bool mysql_close ( [resource spojeni])

Vrací TRUE při úspěchu, FALSE při selhání.

Funkce mysql_close() uzavře spojení s MySQL serverem, které je asociováno se určitým identikátorem spojení Pokud spojeni není zadán uzavře poslední otevřené spojení.

Použití mysql_close() není obvykle nutné, protože nepersistentní (netrvalá) otevřená spojení jsou zavřena automaticky po zpracování scriptu. Dále viz. uvolnění zdrojů.

Poznámka: mysql_close() neuzavře persistentní spojení otevřené pomocí mysql_pconnect().

Příklad 1. Příklad k MySQL close

<?php
    $link = mysql_connect("kraemer", "marliesle", "tajne")
        or exit("Nelze se připojit");
    print ("Spojení navázáno");
    mysql_close($link);
?>

Viz. také: mysql_connect(), a mysql_pconnect().

mysql_connect

(PHP 3, PHP 4 )

mysql_connect -- Vytvoří spojení s MySQL Serverem

Popis

resource mysql_connect ( [string server [, string uziv_jmeno [, string heslo [, bool nove_spojeni]]]])

Je-li spojení úspěšné vrátí identifikátor spojení v opačném případě ???

mysql_connect() vytvoří spojení s MySQL serverem. Nejsou-li zadány nepovinné parametry, použijí se následující hodnoty: server = 'localhost:3306', uziv_jmeno = jméno uživatele, pod kterým běží právě spuštěný skript a heslo = bez hesla.

Parametr server může obsahovat číslo portu ve tvaru "hostname:port" nebo cestu k socketu ve tvaru ":/cesta/k/socketu" pro localhost.

Poznámka: Podpora pro ":port" byla přidána v PHP 3.0B4.

Podpora pro ":/cesta/k/socketu" byla přidána v PHP 3.0.10.

Chybovou hlášku lze potlačit přidáním @ před jméno funkce.

Bude-li funkce mysql_connect() zavolána podruhé se stejnými parametry, nebude vytvořeno nové spojení, ale použije se stávající a je vrácen i stejný identifikátor spojení. Nepovinný parametr nove_spojeni toto chování upravuje a každé volání mysql_connect() vytvoří vždy nové spojení v případě, že funkce mysql_connect() byla volána znovu se stejnými parametry.

Poznámka: Parametr nove_spojeni byl přidán v PHP 4.2.0

Spojení se serverem bude ukončeno automaticky po skončení běhu skriptu nebude-li dříve zavolána funkce mysql_close().

Příklad 1. MySQL příklad spojení

<?php
    $link = mysql_connect("localhost", "uziv_jmeno", "tajne")
        or die("Nelze se připojit");
    print ("Spojení navázáno");
    mysql_close($link);
?>

Viz. také mysql_pconnect() a mysql_close().

mysql_create_db

(PHP 3, PHP 4 )

mysql_create_db -- Vytvoří MySQL databázi

Popis

bool mysql_create_db ( string jméno databáze [, resource spojeni])

mysql_create_db() vytvoří na serveru identifikovaném parametrem spojení novou databázi.

Vrací TRUE při úspěchu, FALSE při selhání.

Příklad 1. MySQL příklad vytvoření nové databáze

<?php
    $link = mysql_pconnect("kron", "jutta", "geheim")
        or exit("Nelze se připojit");
    if (mysql_create_db("moje_db")) {
        print ("Databáze byla vytvořena\n");
    } else {
        printf ("Chyba při vytváření databáze: %s\n", mysql_error ());
    }
?>

Kvůli zpětné kompatibilitě je možné použít i mysql_createdb(). Není to však doporučeno.

Viz. také: mysql_drop_db().

mysql_data_seek

(PHP 3, PHP 4 )

mysql_data_seek -- Přesune ukazatel na aktuální záznam

Popis

bool mysql_data_seek ( zdroj identifikator_vysledku, int cislo_zaznamu)

Vrací TRUE při úspěchu, FALSE při selhání.

mysql_data_seek() přesune interní ukazatel výsledku MySQL na záznam specifikovaný číslem záznamu. Následné volání funkce mysql_fetch_row() načte požadovaný záznam.

Není-li zadáno cislo_zaznamu začíná se od 0. Parametr cislo_zaznamu by mělo být číslo mezi 0 a (mysql_num_rows - 1).

Poznámka: Funkce mysql_data_seek() může být použita pouze ve spolupráci s mysql_query(), ne s mysql_unbuffered_query().

Příklad 1. MySQL příklad přesunutí ukazatele

<?php
    $link = mysql_pconnect("kron", "jutta", "geheim")
        or die("Nelze se připojit");

    mysql_select_db("samp_db")
        or exit("Nelze vybrat databázi");

    $query = "SELECT last_name, first_name FROM friends";
    $result = mysql_query($query)
        or die("Chyba dotazu");

    // načtení záznamů v obráceném pořadí

    for ($i = mysql_num_rows($result) - 1; $i >=0; $i--) {
        if (!mysql_data_seek($result, $i)) {
            echo "Nelze nalézt záznam $i\n";
            continue;
        }

        if(!($row = mysql_fetch_object($result)))
            continue;

        echo "$row->last_name $row->first_name<br />\n";
    }

    mysql_free_result($result);
?>

mysql_db_name

(PHP 3>= 3.0.6, PHP 4 )

mysql_db_name -- Vrátí seznam všech databází

Popis

string mysql_db_name ( resource výsledek, int záznam [, mixed field])

První parametr funkce mysql_db_name() obsahuje identifikátor volání mysql_list_dbs(). Parametr záznam určuje pořadí databáze ve výsledku.

Nastane-li chyba vrací FALSE. Použitím mysql_errno() a mysql_error() zjistíte chybovou hlášku.

Příklad 1. mysql_db_name() příklad

<?php
error_reporting(E_ALL);

mysql_connect('dbhost', 'uziv_jmeno', 'heslo');
$db_list = mysql_list_dbs();

$i = 0;
$cnt = mysql_num_rows($db_list);
while ($i < $cnt) {
    echo mysql_db_name($db_list, $i) . "\n";
    $i++;
}
?>

Kvůli zpětné kompatibilitě lze použít i mysql_dbname(). Není to však doporučeno.

mysql_db_query

(PHP 3, PHP 4 )

mysql_db_query -- Provede MySQL dotaz

Popis

resource mysql_db_query ( string databáze, string dotaz [, resource spojeni])

Vrátí identifikátor výsledku dotazu do určené databáze nebo FALSE nastane-li chyba

mysql_db_query() provede dotaz v databázi specifikované parametrem database. Není-li identifikátor databáze uveden, funkce se pokusí nalézt již otevřené spojení s MySQL serverem. Pokud není žádné aktivní spojení nalezeno, pokusí se vytvořit nové spojení s výchozími hodnotami funkce mysql_connect()

Viz. také mysql_connect() and mysql_query().

Poznámka: Tato funkce není od verze PHP 4.0.6 podporována. Místo této funkce použijtemysql_select_db() a mysql_query().

mysql_drop_db

(PHP 3, PHP 4 )

mysql_drop_db -- Vymaže (odstraní) MySQL databázi

Popis

bool mysql_drop_db ( string database_name [, resource spojeni])

Vrací TRUE při úspěchu, FALSE při selhání.

mysql_drop_db() odstraní ze serveru databázi uvedeného jména pod specifikovaným identifikátorem spojení.

Kvůli zpětné kompatibilitě se můžete setkat i s mysql_dropdb(). Nedoporučujeme však používat. Tento zápis nemusí být v příštích verzích PHP podporován.

Poznámka: Namísto používání funkce mysql_drop_db() se doporučuje ke smazání databáze upřednostnit funkci mysql_query(), do níž je vložen SQL dotaz s příkazem DROP DATABASE.

Příklad 1. mysql_escape_string() příklad

<?php
    $item = "Zak's Laptop";
    $escaped_item = mysql_escape_string($item);
    printf ("Escaped string: %s\n", $escaped_item);
?>

Předchozí příklad by zobrazil následující výstup:

Escaped string: Zak\'s Laptop

Dále také: mysql_real_escape_string(), addslashes() a magic_quotes_gpc directive.

mysql_fetch_array

(PHP 3, PHP 4 )

mysql_fetch_array -- Načte výsledný řádek do asociativního, čísleného pole nebo obojího.

Popis

array mysql_fetch_array ( resource výsledek [, int result_type])

Funkce vrací pole hodnot načteného záznamu nebo FALSE, není-li žádný další řádek.

mysql_fetch_array() je rozšířenou verzí mysql_fetch_row(). Navíc jsou zde data uložena v poli nejen pod číselnými klíči, ale také pod asociativními textovými klíči jmenujícími se podle názvu sloupce sql tabulky.

Pokud dva nebo více sloupců mají stejný název, bude dostupná hodnota pouze toho posledního. Chcete-li přistupovat i k hodnotám ostatních sloupců, musíte k nim v sql dotazu vytvořit aliasy. Název klíče sloupce, k němuž je vytvořem alias, je vždy jméno aliasu a proto není možné použít originální jméno sloupce v sql tabulce (viz. 'sloupec' v následujícím příkladu).

select prvni_tab.sloupec as prvni_sloupec druha_tab.sloupec as druhy_sloupec
from prvni_tab, druha_tab

Důležité ovšem je, že použití mysql_fetch_array() není nijak významně pomalejší než použití mysql_fetch_row(), pokud je její použití přidanou hodnotou.

Nepovinný druhý parametr result_type v mysql_fetch_array() je komstanta, která může nabývat následujících hodnot: MYSQL_ASSOC, MYSQL_NUM, a MYSQL_BOTH. Tato vlastnost byla přidána v PHP 3.0.7. Výchozí hodnota je MYSQL_BOTH.

Použitím MYSQL_BOTH získáte pole s asociativními i číselnými klíči. Použitím MYSQL_ASSOC získáte pole pouze s asociativními klíči (stejně funguje mysql_fetch_assoc()) a použitím MYSQL_NUM, pole obsahovat pouze číselné klíče (tak funguje mysql_fetch_row()).

Příklad 1. mysql_fetch_array s MYSQL_NUM

<?php
    mysql_connect("localhost", "mysql_uziv", "mysql_heslo") or
        die("Nelze se spojit");
    mysql_select_db("mojedb");

    $result = mysql_query("SELECT id, jmeno FROM moje_table");

    while ($row = mysql_fetch_array($result, MYSQL_NUM)) {
        printf ("ID: %s  Jméno: %s", $row[0], $row[1]);  
    }

    mysql_free_result($result);
?>

Příklad 2. mysql_fetch_array s MYSQL_ASSOC

<?php
    mysql_connect("localhost", "mysql_uziv", "mysql_heslo") or
        die("Nelze se spojit");
    mysql_select_db("mojedb");

    $result = mysql_query("SELECT id, jmeno FROM moje_table");

    while ($row = mysql_fetch_array($result, MYSQL_ASSOC)) {
        printf ("ID: %s  Jméno: %s", $row["id"], $row["jmeno"]);
    }

    mysql_free_result($result);
?>

Příklad 3. mysql_fetch_array s MYSQL_BOTH

<?php
    mysql_connect("localhost", "mysql_uziv", "mysql_heslo") or
        die("Nelze se spojit");
    mysql_select_db("mojedb");

    $result = mysql_query("SELECT id, jmeno FROM moje_table");

    while ($row = mysql_fetch_array($result, MYSQL_BOTH)) {
        printf ("ID: %s  Jméno: %s", $row[0], $row["jmeno"]);
    }

    mysql_free_result($result);
?>

Pro další detaily viz. také mysql_fetch_row() a mysql_fetch_assoc().

mysql_fetch_assoc

(PHP 4 >= 4.0.3)

mysql_fetch_assoc -- Načte výsledný řádek do asociativního pole

Popis

array mysql_fetch_assoc ( resource výsledek)

Funkce vrací asociativní pole hodnot vráceného záznamu nebo FALSE, není-li žádný další záznam.

mysql_fetch_assoc() je akvalentem k mysql_fetch_array() s nepovinným druhým parametrem MYSQL_ASSOC, což vrací pouze asociativní pole. Pokud potřebujete používat číselné indexy spolu s asociativními, použijte mysql_fetch_array().

Důležité ovšem je, že použití mysql_fetch_assoc() není nijak významně pomalejší než použití mysql_fetch_row(), pokud je její použití přidanou hodnotou.

Příklad 1. mysql_fetch_assoc()

<?php
mysql_connect($host, $user, $password);
mysql_select_db($databaze);
$query = "select * from tabulka";
$result = mysql_query($query);
while ($row = mysql_fetch_assoc($result)) {
    echo $row["uziv_id"];
    echo $row["celejmeno"];
}
mysql_free_result($result);
?>

Pro další detaily viz. také mysql_fetch_row(), mysql_fetch_array() a mysql_query().

mysql_fetch_field

(PHP 3, PHP 4 )

mysql_fetch_field -- Načte informace o sloupci z výsledku do proměnné objektu

Popis

object mysql_fetch_field ( resource výsledek [, int poradi_sloupce])

Vrátí objekt obsahující informace o sloupci z výsledku.

mysql_fetch_field() můžete použít v případě, že potřebujete získat informace o sloupci z určitého výsledku. Není-li specifikováno pořadí sloupce (počítáno do nuly), funkce načte informace o prvním následujícím ještě nenačteném sloupci.

Vlastnosti objektu jsou:

name - název sloupce
table - název tabulky, v níž se tento sloupec nachází
max_length - maximální délka sloupce ve znacích
not_null - 1 pokud sloupec nemůže být NULL
primary_key - 1 pokud je sloupec primární klíč
unique_key - 1 pokud je sloupec unikátní klíč
multiple_key - 1 pokud je sloupec jiný než unikátní klíč
numeric - 1 pokud je sloupec číslo
blob - 1 pokud je sloupec BLOB
type - typ sloupce
unsigned - 1 pokud je sloupec bez znaménka
zerofill - 1 pokud je sloupec dolpněn nulami na svou velikost

Příklad 1. mysql_fetch_field()

<?php
mysql_connect('localhost:3306', $user, $password)
    or die ("Nelze se připojit");
mysql_select_db("databaze");
$result = mysql_query("select * from tabulka")
    or die("Chyba dotazu");
# vrátí informace o sloupci
$i = 0;
while ($i < mysql_num_fields($result)) {
    echo "Informace pro sloupec $i:<BR>\n";
    $meta = mysql_fetch_field($result);
    if (!$meta) {
        echo "Nejsou dostupné žádné informace<BR>\n";
    }
    echo "<PRE>
blob:         $meta->blob
max_length:   $meta->max_length
multiple_key: $meta->multiple_key
name:         $meta->name
not_null:     $meta->not_null
numeric:      $meta->numeric
primary_key:  $meta->primary_key
table:        $meta->table
type:         $meta->type
unique_key:   $meta->unique_key
unsigned:     $meta->unsigned
zerofill:     $meta->zerofill
</PRE>";
    $i++;
}
mysql_free_result($result);
?>

Viz. také mysql_field_seek().

mysql_fetch_lengths

(PHP 3, PHP 4 )

mysql_fetch_lengths -- Zjistí délku všech položek aktuálního výstupu

Popis

array mysql_fetch_lengths ( resource výsledek)

Vrácí pole obsahující délku každého sloupce v posledně načteném záznamu pomocí mysql_fetch_row(), nebo FALSE dojde-li k chybě.

mysql_fetch_lengths() obsahuje délky hodnot všech vrácených sloupců posledního načteného záznamu pomocí mysql_fetch_row(), mysql_fetch_array(), a mysql_fetch_object() v poli, začínajícího klíčem 0.

Viz. také: mysql_fetch_row().

mysql_fetch_object

(PHP 3, PHP 4 )

mysql_fetch_object -- Načte výsledný záznam do proměnné objektu

Popis

object mysql_fetch_object ( resource výsledek)

Vrácí objekt, jehož proměnné obsahují hodnoty načteného záznamu nebo FALSE není-li žádný další záznam.

mysql_fetch_object() je obdobou mysql_fetch_array(), s jedním rozdílem - narozdíl od pole, je vrácen objekt. Což znamená, že k hodnotám výsledku lze přistupovat pouze přes názvy sloupců a nikoli přes jejich číselné klíče (název vlastnosti nemůže být číslo).

<?php /* tohle je správný zápis */ echo $row->field; /* a toto je chybný zápis */ echo $row->0; ?>

Rychlostně je tato funkce identická s mysql_fetch_array(), a téměr tak rychlá jako mysql_fetch_row() (rozdíl je nevýznamný).

Příklad 1. mysql_fetch_object() příklad

<?php mysql_connect("localhost", "mysql_uziv", "mysql_heslo"); mysql_select_db($db); $result = mysql_query("select uziv_id, celejmeno from tabulka"); while ($row = mysql_fetch_object($result)) { echo $row->uziv_id; echo $row->celejmeno; } mysql_free_result($result); ?>

Viz. také: mysql_fetch_array() a mysql_fetch_row().

mysql_fetch_row

(PHP 3, PHP 4 )

mysql_fetch_row -- Načte výsledný záznam do pole

Popis

array mysql_fetch_row ( resource výsledek)

Funkce vrací číslené pole hodnot načteného záznamu nebo FALSE, není-li žádný další záznam.

mysql_fetch_row() načte jeden záznam výsledku do pole s číslenými klíči. Každá hodnota sloupce je samostatná hodnota pole; klíče jsou číslovány od 0.

Další volání mysql_fetch_row() vrátí následující záznam výsledku, nebo FALSE není-li žádný další záznam.

Viz. také: mysql_fetch_array(), mysql_fetch_object(), mysql_data_seek(), mysql_fetch_lengths() a mysql_result().

mysql_field_flags

(PHP 3, PHP 4 )

mysql_field_flags -- Načte příznaky sloupce tabulky

Popis

string mysql_field_flags ( resource výsledek, int číslo_sloupce)

mysql_field_flags() vrací další informace o uvedeném sloupci tabulky. Každý příznak je reprezentován jedním slovem a jsou od sebe odděleny mezerou tak, že lze výstup snadno rozdělit pomocí funkce explode().

Vrácené příznaky mohou být následující (jestliže je vaše verze MySQL podporuje): "not_null", "primary_key", "unique_key", "multiple_key", "blob", "unsigned", "zerofill", "binary", "enum", "auto_increment", "timestamp".

Z důvodů zpětné kompatibility můžete také narazit na funkci mysql_fieldflags(). Tuto funkci však nedoporučujeme používat, neboť nemusí být již v dalších verzích PHP podporována.

mysql_field_len

(PHP 3, PHP 4 )

mysql_field_len -- Vrací délku sloupce tabulky

Popis

int mysql_field_len ( resource výsledek, int číslo_sloupce)

mysql_field_len() vrací délku uvedeného sloupce v tabulce.

Z důvodů zpětné kompatibility můžete také narazit na funkci mysql_fieldlen(). Tuto funkci však nedoporučujeme používat, neboť nemusí být již v dalších verzích PHP podporována.

mysql_field_name

(PHP 3, PHP 4 )

mysql_field_name -- Načte název sloupce tabulky

Popis

string mysql_field_name ( resource výsledek, int číslo_sloupce)

mysql_field_name() vrací jméno uvedeného sloupce v tabulce. výsledek musí být platný identifikátor spojení a číslo_sloupce je pořadí sloupce v tabulce.

Poznámka: číslo_sloupce začíná nulou.

Např. pořadí třetího sloupce tabulky bude číslo 2, čtvrtý sloupec v tabulce má číslo 3, atd.

mysql_free_result() uvolní pamět obsazenou výsledkem definovaným identifikátorem spojení vysledek.

mysql_free_result() je vhodné používat pouze v případě, kdy vám záleží na tom, jak moc paměti je v průběhu skriptu použíto pro vykonaný dotaz a když výsledek dotazu je příliš velký. Všechna paměť obsazená výsledky spojení bude jinak automaticky ulovněna až s koncem běhu skriptu.

Vrací TRUE při úspěchu, FALSE při selhání.

Z důvodů zpětné kompatibility můžete také narazit na funkci mysql_freeresult(). Tuto funkci však nedoporučujeme používat, neboť nemusí být již v dalších verzích PHP podporována.

mysql_get_client_info

(PHP 4 >= 4.0.5)

mysql_get_client_info -- Načte verzi klientské knihovny MySQL

Popis

string mysql_get_client_info ( void)

mysql_get_client_info() vrací řetězec obsahující verzi používané klientské knihovny MySQL.

Příklad 1. mysql_get_client_info Příklad

<?php
    printf ("MySQL klient info: %s\n", mysql_get_client_info());
?>

TPředchozí příklad by mohl mít následující výstup:

MySQL klient info: 3.23.39

Dále také: mysql_get_host_info(), mysql_get_proto_info() z mysql_get_server_info().

mysql_get_host_info

(PHP 4 >= 4.0.5)

mysql_get_host_info -- Načte informaci o hostu

Popis

string mysql_get_host_info ( [resource spojeni])

mysql_get_host_info() vrací řetězec popisující použitý typ spojení v spojeni, obsahující server host name. Pokud je spojeni vynecháno, použije posledně otevřené spojení.

Příklad 1. mysql_get_host_info Příklad

<?php
    mysql_connect("localhost", "mysql_uziv", "mysql_heslod") or
        die("Nelze se spojit");
    printf ("MySQL host info: %s\n", mysql_get_host_info());
?>

Předchozí příklad by mohl mít následující výstup:

MySQL host info: Localhost via UNIX socket

Dále také: mysql_get_client_info(), mysql_get_proto_info() and mysql_get_server_info().

mysql_get_proto_info

(PHP 4 >= 4.0.5)

mysql_get_proto_info -- Načte informaci o protokolu MySQL

Popis

int mysql_get_proto_info ( [resource spojeni])

mysql_get_proto_info() vrací číslo verze protokolu v použitém spojeni. Je-li spojeni vynecháno, použije se posledně otevřené spojení.

Příklad 1. mysql_get_proto_info Příklad

<?php
    mysql_connect("localhost", "mysql_uziv", "mysql_heslo") or
        die("Nelze se spojit");
    printf ("Verze protokolu MySQL: %s\n", mysql_get_proto_info());
?>

Předchozí příklad by mohl mít následující výstup:

Verze protokolu MySQL : 10

Dále také: mysql_get_client_info(), mysql_get_host_info() a mysql_get_server_info().

mysql_get_server_info

(PHP 4 >= 4.0.5)

mysql_get_server_info -- Načte informace o serveru MySQL

Popis

int mysql_get_server_info ( [resource spojeni])

mysql_get_server_info() vrací verzi serveru v použitém spojeni. Pokud je spojeni vynecháno, použije se posledně otevřené spojení.

Příklad 1. mysql_get_server_info Příklad

<?php
    mysql_connect("localhost", "mysql_uziv", "mysql_heslo") or
        die("Nelze se spojit");
    printf ("Verze MySQL serveru: %s\n", mysql_get_server_info());
?>

Předchozí příklad by mohl mít následující výstup:

Verze MySQL serveru: 4.0.1-alpha

Dále také: mysql_get_client_info(), mysql_get_host_info() a mysql_get_proto_info().

mysql_info

(PHP 4 CVS only)

mysql_info -- Vrací informace o posledním dotazu

Popis

string mysql_info ( [resource spojeni])

mysql_info() vrací detailní informace o posledním dotazu v použitém spojeni. Pokud spojeni není uvedeno, použije se poslední otevřené spojení.

mysql_info() vrací řetezec z všemi dotazy vylistovanými níže. Pro všechny ostatní FALSE. Formát řetězce je závislý na použitém typu dotazu.

Příklad 1. Příslušné MySQL dotazy

INSERT INTO ... SELECT ... String format: Records: 23 Duplicates: 0 Warnings: 0 INSERT INTO ... VALUES (...),(...),(...)... String format: Records: 37 Duplicates: 0 Warnings: 0 LOAD DATA INFILE ... String format: Records: 42 Deleted: 0 Skipped: 0 Warnings: 0 ALTER TABLE String format: Records: 60 Duplicates: 0 Warnings: 0 UPDATE String format: Rows matched: 65 Changed: 65 Warnings: 0
Čísla uvedená v příkladu jsou jen pro ilustraci; jejich hodnoty budou shodné s výsledkem dotazu.

Poznámka: mysql_info() vrací hodnotu jinou než FALSE v případě dotazu INSERT ... VALUES, ve kterém jsou uvedeny hodnoty pro zápis více záznamů najednou.

Dále také: mysql_affected_rows()

mysql_insert_id

(PHP 3, PHP 4 )

mysql_insert_id -- Vrací generovanou hodnotu id posledního příkazu INSERT

Popis

int mysql_insert_id ( [resource spojeni])

mysql_insert_id() vrací hodnotu ID vygenerovanou pro sloupec AUTO_INCREMENT předchozím dotazem typu INSERT indetifikovaný parametrem spojeni. Pokud je spojeni vynecháno, použije se posledně otevřené spojení.

mysql_insert_id() vrací 0 pokud pro předchozí dotaz nebyla vygenerována žádná hodnota pomocí AUTO_INCREMENT. I v případě, že potřebujete hodnotu použít později, dbejte na to, abyste funkci mysql_insert_id() volali okamžitě po dotazu, pro nějž byla vygenerována hodnota pomocí AUTO_INCREMENT.

Poznámka: Hodnota MySQL SQL funkce LAST_INSERT_ID() vždy obsahuje nejvyšší posledně vygenerovanou hodnotu AUTO_INCREMENT a není mezi dalšími dotazy vynulována.

Varování

mysql_insert_id() převádí typ vrácený nativní MySQL C API funkcí mysql_insert_id() z typu long (ekvivalent v PHP int). Pokud je sloupec AUTO_INCREMENT typu BIGINT, hodnota vrácená mysql_insert_id() bude nesprávná (pouze v případě, že i samotná hodnota bude mít velikost BIGINT). Místo toho použijte vnitřní MySQL SQL funkci LAST_INSERT_ID() přímo v SQL dotazu.

Příklad 1. mysql_insert_id Příklad

<?php
    mysql_connect("localhost", "mysql_uziv", "mysql_heslo") or
        die("Nelze se spojit");
    mysql_select_db("mojedb");

    mysql_query("INSERT INTO mojetabulka (produkt) values ('kosa')");
    printf ("Posledně vložený záznam má id: %d\n", mysql_insert_id());
?>

Dále také: mysql_query().

mysql_list_dbs

(PHP 3, PHP 4 )

mysql_list_dbs -- Načte všechny dostupné databáze na MySQL serveru

Popis

resource mysql_list_dbs ( [resource spojeni])

mysql_list_dbs() vrací ukazatel výsledku obsahující databáze dostupné na aktuálním mysql démonovi. Lze použít například společně s funkcí mysql_tablename() k získání názvů tabulek, případně jiných funkcích k získání dalších informací o tabulkách.

Příklad 1. mysql_list_dbs() příklad

<?php $link = mysql_connect('localhost', 'mojejmeno', 'tajne'); $db_list = mysql_list_dbs($link); while ($row = mysql_fetch_object($db_list)) { echo $row->Database . "\n"; } ?>

Předchozí příklad by měl následující výstup:

databaze1 databaze2 databaze3 ...

Poznámka: Předchozí kód by tak snadno pracoval i s mysql_fetch_row() či podobnými funkcemi.

Z důvodů zpětné kompatibility můžete také narazit na funkci mysql_listdbs(). Tuto funkci však nedoporučujeme používat, neboť nemusí být již v dalších verzích PHP podporována.

Viz. také mysql_db_name().

mysql_list_fields

(PHP 3, PHP 4 )

mysql_list_fields -- Načte výsledek s obsahem sloupce

Popis

resource mysql_list_fields ( string jmeno_databaze, string table_name [, resource spojeni])

mysql_list_fields() vrací ukazatel výsledku o sloupcích uvedené tabulky. Argumentu jsou jméno databáze a jméno tabulky. Vrácený ukazatel výsledku může být použit spolu s funkcemi mysql_field_flags(), mysql_field_len(), mysql_field_name(), a mysql_field_type().

Příklad 1. mysql_list_fields() příklad

<?php $link = mysql_connect('localhost', 'mojejmeno', 'tajne'); $fields = mysql_list_fields("databaze1", "tabulka1", $link); $columns = mysql_num_fields($fields); for ($i = 0; $i < $columns; $i++) { echo mysql_field_name($fields, $i) . "\n"; } ?>

Předchozí příklad by mohl mít následující výstup:

sloupec1 sloupec2 sloupec3 ...

Z důvodů zpětné kompatibility můžete také narazit na funkci mysql_listfields(). Tuto funkci však nedoporučujeme používat, neboť nemusí být již v dalších verzích PHP podporována.

mysql_list_processes

(PHP 4 CVS only)

mysql_list_processes -- List MySQL processes

Popis

resource mysql_list_processes ( [resource spojeni])

mysql_list_processes() vrací ukazatel popisující aktuální vlákna serveru.

Příklad 1. mysql_list_processes() příklad

<?php $link = mysql_connect('localhost', 'mysql_jmeno', 'mysql_heslo'); $result = mysql_list_processes($link); while ($row = mysql_fetch_row($result)){ printf("%s %s %s %s %s\n", $row["Id"], $row["Host"], $row["db"], $row["Command"], $row["Time"]); } mysql_free_result ($result); ?>

Předchozí příklad by zobrazit následující výstup:

1 localhost test Processlist 0 4 localhost mysql sleep 5

mysql_list_tables

(PHP 3, PHP 4 )

mysql_list_tables -- Načte všechny tabulky v MySQL databázi

Popis

resource mysql_list_tables ( string database [, resource spojeni])

mysql_list_tables() Na základě jména databáze vrací ukazatel výsledku na tabulky přesně tak jako mysql_db_query(). Použítím funkce mysql_tablename() můžete zjistit jména všech tabulek z ukazatele výsledku nebo použít jiné funkce k zjištění dalších informací jako např. mysql_fetch_assoc().

Parametr database je název databáze, z které se mají číst jména tabulky. Dojde-li k chybě, mysql_list_tables() vrací FALSE.

Z důvodů zpětné kompatibility můžete také narazit na funkci mysql_listtables(). Tuto funkci však nedoporučujeme používat, neboť nemusí být již v dalších verzích PHP podporována.

Příklad 1. mysql_list_tables Příklad

<?php
    $dbname = 'mysql_dbjmeno';

    if (!mysql_connect('mysql_host', 'mysql_uziv', 'mysql_heslo')) {
        print 'Nelze se spojit';
        exit;
    }

    $result = mysql_list_tables($dbname);
    
    if (!$result) {
        print "Chyba DB, nelze číst tabulky\n";
        print 'MySQL chyba: ' . mysql_error();
        exit;
    }
    
    while ($row = mysql_fetch_row($result)) {
        print "Tabulka: $row[0]\n";
    }

    mysql_free_result($result);
?>

Poznámka: Podpora pro ":port" byla přidána v PHP 3.0B4.

Podpora pro ":/cesta/k/soketu" byla přidána v PHP 3.0.10.

Funkce mysql_pconnect() je velmi podobná funkci mysql_connect() s dvěma hlavními rozdíly.

Za prvé, funkce se nejprve pokusí nalézt již existující (persistentní) spojení otevřené na stejném portu pod stejným jménem a heslem. Je-li takové spojení nalezeno, použije se namísto vytváření nového.

Za druhé, spojení s SQL serverem nebude uzavřeno při ukončení běhu skriptu. Zůstane otevřeno pro použití v dalších skriptech, které teprve budou spouštěny (mysql_close() neuzavře persistentní spojení vytvořené pomocí mysql_pconnect()).

Proto je tento typ spojení nazýván jako 'persistentní' - trvalý.

Poznámka: Persistentní spojení funguje pouze v případě, kdy je PHP spuštěno jako modul (nikoli CGI). Více o této problematice naleznete v sekci Persistentní databázová spojení.

Varování

Používání persistetního spojení může vyžadovat malou úpravu v konfiguraci Apache a MySQL k zajištění nepřekročení maximálního limitu povolených připojení k MySQL.

mysql_ping

(PHP 4 CVS only)

mysql_ping -- Ověří spojení se serverem, případně, není-li spojení dostupné, pokusí se připojit znovu.

Popis

bool mysql_ping ( [resource spojeni])

mysql_ping() zkouší, zda je či není spojení se serverem. V případě, že spojení je ztraceno, automaticky se pokusí vytvořit nové spojení. Tato funkce může být použita ve scriptech, které zůstávají dlouho dobu nečinné k zjištění, zda je sepojení se serverem již zavřeno a v případě nutnosti navážou automaticky spojení nové. mysql_ping() vrací TRUE pokud je spojení navázáno, jinak FALSE.

Dále také: mysql_thread_id(), mysql_list_processes().

mysql_query

(PHP 3, PHP 4 )

mysql_query -- Pošle MySQL dotaz

Popis

resource mysql_query ( string query [, resource spojeni])

mysql_query() Provede dotaz na aktuálním spojení v aktivní databázi na serveru a vrátí identifikátor výsledku. Není-li parametr spojeni uveden, použije posledně otevřené spojení. Pokud není žádné otevřené spojení nalezeno, funkce se ho pokusí vytvořit za použití výchozích hodnot funkce mysql_connect() (jakoby byla volána bez parametrů)

Poznámka: Řetězec dotazu by neměl končit středníkem.

Pouze při použití dotazu typu SELECT je vrácen identifikátor výsledku či FALSE pokud při vykonávání dotazu došlo k chybě. Při ostatních typech dotazů mysql_query() vrací TRUE při úspěšném dotazu nebo FALSE dojde-li k chybě. Ne-FALSE vrácená hodnota znamená, že dotaz byl vykonán serverem bez chyb. Tato funkce nezaznamenává žádné údaje o počtu ovlivněných nebo vrácených řádků. Lze pouze zjistit, zda dotaz proběhl v pořádku.

Následující dotaz je syntakticky nesprávný, takže jeho vykonávání v mysql_query() selže a vrátí FALSE:

Příklad 1. mysql_query()

<php $result = mysql_query("SELECT * WHERE 1=1") or die("Špatný dotaz!"); ?>

Následující dotaz je významově nesprávný my_col není sloupec v tabulce my_tbl, takže mysql_query() selže a vrátí FALSE:

Příklad 2. mysql_query()

<?php $result = mysql_query("SELECT my_col FROM my_tbl") or exit ("Špatný dotaz!"); ?>

mysql_query() také vždy selže a vrátí FALSE jestliže nemáte dostatečné oprávnění přístupu do tabulky (tabulek) uvedených v dotazu.

Potřebujete-li zjistit počet záznamů vrácených dotazem typu SELECT, použijte následně funkci mysql_num_rows() či případně funkci mysql_affected_rows(), pokud potřebujete zjistit počet všech ovlivněných záznamů dotazy typů DELETE, INSERT, REPLACE nebo UPDATE.

Pouze při dotazu typu SELECT mysql_query() vrací nový identifikátor dotazu, který lze použít například pro volání funkce mysql_fetch_array() a dalších funkcí pro zpracování výsledků dotazu. Nepotřebujete-li již obsah výsledku dotazu, můžete uvolnit pamět voláním funkce mysql_free_result(). Nicméně pamět bude stejně uvolněna automaticky na konci běhu skriptu.

Viz. také: mysql_num_rows() mysql_affected_rows(), mysql_unbuffered_query(), mysql_free_result(), mysql_fetch_array(), mysql_fetch_row(), mysql_fetch_assoc(), mysql_result(), mysql_select_db(), a mysql_connect().

mysql_real_escape_string

(PHP 4 CVS only)

mysql_real_escape_string -- Upraví řetězec pro bezpečné použití v mysql_query.

Popis

string mysql_real_escape_string ( string neupraveny_retezec [, resource spojeni])

Tato funkce opatří speciální znaky v neupraveny_retezec zpětným lomítkem pro bezpečné použití v mysql_query() v závislosti na aktuální znakové sadě spojení (konce řádků jsou nahrazeny značkou \n atd.).

Poznámka: mysql_real_escape_string() nepřidává zpětná lomítka před % and _.

Příklad 1. mysql_real_escape_string() příklad

<?php
$link = mysql_connect('localhost', 'mysql_user', 'mysql_password');
$item = "Zak's and Derick's Laptop";
$escaped_item = mysql_real_escape_string($item);
printf ("Escaped string: %s\n", $escaped_item);
?>

Předchozí příklad by zobrazil následující výstup:

Escaped string: Zak\'s and Derick\'s Laptop

Dále také: mysql_escape_string(), mysql_character_set_name().

mysql_result

(PHP 3, PHP 4 )

mysql_result -- Načte obsah jednoho sloupce tabulky

Popis

mixed mysql_result ( resource výsledek, int záznam [, mixed field])

mysql_result() vrací záznamy jednoho sloupce z výsledku MySQL. Argumenty mohou být číslo sloupce, jméno sloupce, jméno tabulky nebo jméno tabulky tečka jméno sloupce (tabulka.sloupec). Má-li některý sloupec jmenný alias (SELECT muj_sloupec as tvuj_sloupec FROM ...), používejte alias namísto jméno sloupce.

Pokud pracujete s velkými záznamy, měli byste uvážit použití jedné z funkcí, které vrací úplně celý záznam (všechny sloupce specifikované v dotazu SELECT najednou), protože tyto funkce vrací celý výsledek v jednom volání funkce a jsou proto MNOHEM rychlejší než mysql_result(). Dále je nutné podotknout, že jako argument sloupce je mnohem rychlejší uvést číselný identifikátor než jméno sloupce či zápis tabulka.sloupec.

Volání funkce mysql_result() by nemělo být mícháno s voláním jiných funkcí, protože by došlo k dělení záznamů z výsledku.

Doporučené mnohem výkonější alternativy: mysql_fetch_row(), mysql_fetch_array() a mysql_fetch_object().

mysql_select_db

(PHP 3, PHP 4 )

mysql_select_db -- Nastaví MySQL databázi

Popis

bool mysql_select_db ( string jmeno_databaze [, resource spojeni])

Vrací TRUE při úspěchu, FALSE při selhání.

mysql_select_db() nastaví aktuální databázi na serveru a asocijuje ji s uvedeným identifikátorem spojení. Není-li identifikátor spojení uveden, použije posledně otevřené spojení. Není-li žádné spojení otevřeno, funkce se jej pokusí vytvořit tak, jakoby byla volána funkce mysql_connect() bez parametrů.

Každé další volání mysql_query() bude vytvořeno už na platnou databázi.

Viz. také: mysql_connect(), mysql_pconnect() a mysql_query().

Z důvodů zpětné kompatibility můžete také narazit na funkci mysql_selectdb(). Tuto funkci však nedoporučujeme používat, neboť nemusí být již v dalších verzích PHP podporována.

mysql_stat

(PHP 4 CVS only)

mysql_stat -- Vrací aktuální stav systému

popis

string mysql_stat ( [resource spojeni])

mysql_stat() vrací aktuální stav systému.

Poznámka: mysql_stat() vrací hodnoty stavů pouze pro čas od startu MySQL serveru, vlákna, pomalé dotazy, otevřené tabulky, flush tabulky a dotazy za sekundu. Pro kompletní výpis stavů dalších proměnných musíte použít sql dotaz SHOW STATUS.

Příklad 1. mysql_stat() příkaz

<?php $link = mysql_connect('localhost', "mysql_uziv", "mysql_heslo"); printf("%s\n", mysql_stat($link)); ?>

předchozí příklad by zobrazil následující výstup:

Uptime: 5380 Threads: 1 Questions: 1321299 Slow queries: 1 Opens: 26 Flush tables: 1 Open tables: 17 Queries per second avg: 245.595

mysql_tablename

(PHP 3, PHP 4 )

mysql_tablename -- Načte jméno tabulky

Popis

string mysql_tablename ( resource výsledek, int i)

mysql_tablename() vezme identifikátor výsledku vrácený funkcí mysql_list_tables(), což je celočíslený index a vrátí jméno tabulky. K určení celočísleného indexu může být pouřžita funkce mysql_num_rows().

Příklad 1. mysql_tablename() Příklad

<?php mysql_connect("localhost", "mysql_uziv", "mysql_heslo"); $result = mysql_list_tables("mojedb"); for ($i = 0; $i < mysql_num_rows($result); $i++) printf ("Tabulka: %s\n", mysql_tablename($result, $i)); mysql_free_result($result); ?>

Dále také: mysql_list_tables().

mysql_thread_id

(PHP 4 CVS only)

mysql_thread_id -- Vrátí id aktuálního vlákna

Popis

int mysql_thread_id ( [resource spojeni])

mysql_thread_id() Vrátí id aktuálního vlákna. Je-li spojení ztraceno a znovu navázáno pomocí mysql_ping(), id vlánka bude jiné.

Příklad 1. mysql_thread_id() příklad

<?php
$link = mysql_connect('localhost', 'mysql_uziv', 'mysql_heslo');
$thread_id = mysql_thread_id($link);
if ($thread_id){
    printf ("id aktuálního vlákna je %d\n", $thread_id);
}
?>

Předchozí příklad by zobrazil následující výstup:

id aktuálního vlákna je 73

Dále také: mysql_ping(), mysql_list_processes().

mysql_unbuffered_query

(PHP 4 >= 4.0.6)

mysql_unbuffered_query -- Pošle SQL dotaz bez načtení a bufferování výsledných záznamů

Popis

resource mysql_unbuffered_query ( string dotaz [, resource spojeni])

mysql_unbuffered_query() pošle SQL dotaz dotaz do MySQL bez načtení a bufferování výsledných záznamů automaticky, jako to dělá funkce mysql_query(). Na jednu stranu toto chování ušetří značné množství použité paměti u SQL dotazů, které vytvářejí rozsáhlé výsledky. Na druhou stranu můžete začít pracovat na výsledku okamžitě po prvním záznamu, který byl vrácen; tj. nemusíte čekat dokud nebude proveden celý SQL dotaz. Použijete-li přepínač DB-connects, můžete zadat volitelný parametr spojeni.

Poznámka: každá výhoda mysql_unbuffered_query() něco stojí: Nemůžete používat funkci mysql_num_rows() k zjištění počtu záznamů vrácených pomocí mysql_unbuffered_query(). Dále také musíte načíst všechny záznamy vracené nebufferovaným dotazem předtím, než pošlete nový SQL dotaz do MySQL.

Viz. také: mysql_query().

LXIV. Mohawk Software session handler functions

msession is an interface to a high speed session daemon which can run either locally or remotely. It is designed to provide consistent session management for a PHP web farm.

The session server software can be found at http://www.mohawksoft.com/phoenix/.

Obsah
msession_connect -- Connect to msession server
msession_count -- Get session count
msession_create -- Create a session
msession_destroy -- Destroy a session
msession_disconnect -- Close connection to msession server
msession_find -- Find value
msession_get_array -- Get array of ... ?
msession_get -- Get value from session
msession_getdata -- Get data ... ?
msession_inc -- Increment value in session
msession_list -- List ... ?
msession_listvar -- List sessions with variable
msession_lock -- Lock a session
msession_plugin -- Call an escape function within the msession personality plugin
msession_randstr -- Get random string
msession_set_array -- Set array of ...
msession_set -- Set value in session
msession_setdata -- Set data ... ?
msession_timeout -- Set/get session timeout
msession_uniq -- Get uniq id
msession_unlock -- Unlock a session

LXV. muscat functions

Obsah
muscat_close -- Shuts down the muscat session and releases any memory back to PHP.
muscat_get -- Gets a line back from the core muscat API.
muscat_give -- Sends string to the core muscat API
muscat_setup_net -- Creates a new muscat session and returns the handle.
muscat_setup -- Creates a new muscat session and returns the handle.

(4.0.5 - 4.2.1 only)

muscat_setup_net -- Creates a new muscat session and returns the handle.

Description

resource muscat_setup_net ( string muscat_host, int port)

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

muscat_host is the hostname to connect to port is the port number to connect to - actually takes exactly the same args as fsockopen

muscat_setup

(4.0.5 - 4.2.1 only)

muscat_setup -- Creates a new muscat session and returns the handle.

Description

resource muscat_setup ( int size [, string muscat_dir])

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

Size is the ammount of memory in bytes to allocate for muscat muscat_dir is the muscat installation dir e.g. "/usr/local/empower", it defaults to the compile time muscat directory

LXVI. Síťové funkce

Obsah
checkdnsrr -- Ověří DNS záznamy odpovídající danému názvu počítače na Internetu nebo jeho IP adrese.
closelog -- Zavře spojení do systémového protokolu
debugger_off -- Vypne vnitřní PHP debugger
debugger_on -- Zapne vnitřní PHP debugger
define_syslog_variables -- Inicializuje všechny konstanty související se systémovým protokolem
fsockopen -- Otevře socketové spojení v internetové nebo unixové doméně.
gethostbyaddr -- Vrací intertnetové jméno počítače, odpovídající dané IP adrese
gethostbyname -- Vrací IP adresu odpovídající danému internetovému jménu počítače
gethostbynamel -- Vracé seznam IP adres odpovídajících danému internetovému jménu počítače
getmxrr -- Vrací MX záznamy odpovídající dané internetové jmenné adrese
getprotobyname -- Vrací číslo protokolu podle názvu tohoto protokolu
getprotobynumber -- Vrací název protokolu podle čísla tohoto protokolu
getservbyname -- Vrací číslo portu podle internetové služby a protokolu
getservbyport -- Vrací internetovou službu odpovídající specifikovanému portu a protokolu
ip2long -- Převede řetězec obsahující internetovou (IPv4) adresu v tečkové notaci na odpovídající adresu.
long2ip -- Převede internetovou (IPv4) adresu na řetězec ve standardním tečkovém formátu
openlog -- Otevře spojení do systémového protokolu
pfsockopen -- Otevře perzistentní (přetrvávající) socketové spojení v internetové nebo unixové doméně
socket_get_status -- Vrací informace o existujícím socketovém proudu
socket_set_blocking -- Nastavuje blokující/neblokující režim socketu
socket_set_timeout -- Nastaví časový limit (timeout) socketu
syslog -- Vygeneruje zprávu do systémového protokolu

checkdnsrr

(PHP 3, PHP 4 )

checkdnsrr -- Ověří DNS záznamy odpovídající danému názvu počítače na Internetu nebo jeho IP adrese.

Popis

int checkdnsrr ( string host [, string type])

Prohledá DNS na záznamy typu type, odpovídající názvu host. Vrací TRUE, pokud najde nějaké záznamy a FALSE, pokud nic nenajde nebo nastane chyba.

type může být jeden z těchto: A, MX, NS, SOA, PTR, CNAME, or ANY. Implicitní je MX.

Host může být jak IP adresa (v "tečkové" notaci), tak název stroje.

Poznámka: Tato funkce není implementována na platformách Windows.

Viz také getmxrr(), gethostbyaddr(), gethostbyname(), gethostbynamel(), a manuálovou stránku named(8).

closelog

(PHP 3, PHP 4 )

closelog -- Zavře spojení do systémového protokolu

Popis

int closelog ( void)

void define_syslog_variables ( void)

Inicializuje všechny konstanty použité ve funkcích systémového protokolu.

Viz také openlog(), syslog() a closelog().

fsockopen

(PHP 3, PHP 4 )

fsockopen -- Otevře socketové spojení v internetové nebo unixové doméně.

Popis

int fsockopen ( string hostname, int port [, int errno [, string errstr [, float timeout]]])

Iniciuje proudové spojení v internetové (AF_INET, za použití TCP nebo UDP) nebo unixové (AF_UNIX) doméně. Pro internetovou doménu otevře TCP kanál na stroj hostname na port port. hostname v takovém případě může být plně určené doménové jméno nebo IP adresa. Pro spojení UDP musíte explicitně specifikovat protokol předřazením 'udp://' před hostname. V unixové doméně se hostname použije jako cesta k socketu port se pak musí nastavit na 0. Nepovinný parametr timeout se může použít k nastavení time-outu pro systémové volání connect.

Od PHP 4.3.0, pokud jste PHP zkompilovali s podporou OpenSSL, můžete před hostname předřadit 'ssl://' nebo 'tls://' pro použití SSL nebo TSL spojení na vzdálený stroj přes TCP/IP.

fsockopen() vrací deskriptor souboru, který lze použít s jinými souborovými funkcemi (např. fgets(), fgetss(), fputs(), fclose() a feof()).

Pokud volání selže, vrací funkce FALSE, a pokud jsou přítomny nepovinné parametry errno a errstr, budou nastaveny na aktuální chybovou úroveň v systémovém volání connect(). Je-li vrácená hodnota v errno rovna 0 a funkce vrátila FALSE, znamená to, že chyba nastala před voláním connect(). Nejčastěji je to kvůli problému při inicializaci socketu. Uvědomte si, že argumenty errno a errstr se vždy předávají odkazem.

V závislosti na prostředí nemusí být k dispozici unixová doména nebo volitelný parametr timeout.

Socket se implicitně otevře v blokujícím režimu. Do neblokujícího režimu ho můžete přepnout použitím socket_set_blocking().

Příklad 1. fsockopen() Příklad

<?php $fp = fsockopen ("www.example.com", 80, $errno, $errstr, 30); if (!$fp) { echo "$errstr ($errno)<br>\n"; } else { fputs ($fp, "GET / HTTP/1.0\r\nHost: www.example.com\r\n\r\n"); while (!feof($fp)) { echo fgets ($fp,128); } fclose ($fp); } ?>
Další (níže uvedený) příklad ukazuje, jak získat datum a čas z UDP služby "daytime" (port 13) na vašem vlastním počítači.

Příklad 2. Použití UDP spojení

<?php $fp = fsockopen("udp://127.0.0.1", 13, $errno, $errstr); if (!$fp) { echo "CHYBA: $errno - $errstr<br>\n"; } else { fwrite($fp,"\n"); echo fread($fp, 26); fclose($fp); } ?>

Poznámka: Parametr timeout by zaveden v PHP 3.0.9 a podpora UDP v PHP 4.

int ip2long ( string ip_address)

Funkce ip2long() generuje síťovou IPv4 adresu ze standardního internetového formátu (čísla oddělená tečkami).

Příklad 1. ip2long() Příklad

<?php $ip = gethostbyname("www.example.com"); $out = "Následující URL jsou ekvivalentní:<br>\n"; $out .= "http://www.example.com/, http://".$ip."/, and http://".sprintf("%u",ip2long($ip))."/<br>\n"; echo $out; ?>

Poznámka: Protože celé číslo (integer) v PHP obsahuje znaménko a mnoho IP adres vyjde jako záporné, musíte k získání správné (nezáporné) hodnoty použít funkce sprintf() nebo printf() vždy s formátovačem %u.

Tento druhý příklad ukazuje, jak tiskout zkonvertovanou adresu funkcí printf():

Příklad 2. Zobrazení IP adresy

<?php
$ip = gethostbyname("www.example.com");
printf("%u\n", ip2long($ip));
echo $out;
?>

Viz také: long2ip()

long2ip

(PHP 4 )

long2ip -- Převede internetovou (IPv4) adresu na řetězec ve standardním tečkovém formátu

Popis

string long2ip ( int proper_address)

Funkce long2ip() generuje internetovou adresu v tečkovém formátu (např. aaa.bbb.ccc.ddd) z číselné reprezentace adresy.

Viz také: ip2long()

openlog

(PHP 3, PHP 4 )

openlog -- Otevře spojení do systémového protokolu

Popis

int openlog ( string ident, int option, int facility)

openlog() otevře pro program spojení do systémového protokolu. Do každé zprávy se přidá řetězec ident. Hodnoty pro option a facility jsou uvedeny níže. Parametr option se používá k určení, které volby budou při generování zprávy použity. Argument facility specifikuje, jaký typ programu zaznamenává zprávu. To umožňuje specifikovat (v konfiguraci systémového protokolu na vašem počítači), jak budou zprávy přicházející z různých zdrojů obsluhovány. Použití openlog() není povinné. Volá se automaticky ze syslog() v případě potřeby; v takovém případě bude ident implicitně FALSE.

Tabulka 1. openlog() Volby

Konstanta	Popis
LOG_CONS	při chybě během posílání dat do protokolu zapisuj přímo na systémovou konzoli
LOG_NDELAY	ihned otevři spojení do protokolu
LOG_ODELAY	(implicitní) otevři spojení až v okamžiku zápisu první zprávy
LOG_PERROR	tiskni zprávy také na standardní chybový výstup (stderr)
LOG_PID	do každé zprávy přidej PID

Můžete použít jednu nebo více voleb. V případě použití více voleb je musíte spojit pomocí OR, tedy např. "otevři spojení ihned, zapisuj na konzoli a přidej PID" bude vypadat: LOG_CONS | LOG_NDELAY | LOG_PID

Tabulka 2. openlog() Charaktery

Konstanta	Popis
LOG_AUTH	bezpečnostní/autorizační zprávy (použijte raději LOG_AUTHPRIV na systémech, kde je tato konstanta definována)
LOG_AUTHPRIV	bezpečnostní/autorizační zprávy (soukromé)
LOG_CRON	časový démon (cron a at)
LOG_DAEMON	ostatní démoni systému
LOG_KERN	zprávy jádra
LOG_LOCAL0 ... LOG_LOCAL7	vyhrazeno pro místní použití
LOG_LPR	subsystém tiskárny
LOG_MAIL	poštovní subsystém
LOG_NEWS	subsystém USENET news
LOG_SYSLOG	zprávy generované vnitřně démonem syslogd
LOG_USER	generické uživatelské zprávy
LOG_UUCP	subsystém UUCP

Viz také define_syslog_variables(), syslog() a closelog().

pfsockopen

(PHP 3>= 3.0.7, PHP 4 )

pfsockopen -- Otevře perzistentní (přetrvávající) socketové spojení v internetové nebo unixové doméně

Popis

int pfsockopen ( string hostname, int port [, int errno [, string errstr [, int timeout]]])

Tato funkce se chová naprosto stejně jako fsockopen(), s tím rozdílem, že spojení se po skončení skriptu neuzavře. Je to perzistentní verze fsockopen().

socket_get_status

(PHP 4 )

socket_get_status -- Vrací informace o existujícím socketovém proudu

Popis

array socket_get_status ( resource socketstream)

Vrací informace o existujícím socketovém streamu. Tato funkce pracuje pouze na socketu vytvořeném pomocí fsockopen(), pfsockopen() a síťových socketech vrácených funkcí fopen() s URL jako parametrem. NEFUNGUJE se sockety ze Socketového rozšíření. Ve výsledkovém poli v současné době vrací čtyři položky:

timed_out (bool) - Vypršel časový limit pro čekání na data
blocked (bool) - Socket byl zablokován
eof (bool) - Indikuje konec souboru (EOF)
unread_bytes (int) - Počet bytů zbývajících v bufferu socketu

Viz také: Socketové rozšíření.

socket_set_blocking

(PHP 4 )

socket_set_blocking -- Nastavuje blokující/neblokující režim socketu

Popis

int socket_set_blocking ( int socket descriptor, int mode)

Pokud má mode hodnotu FALSE, příslušný deskriptor socketu se přepne do neblokujícího režimu; je-li TRUE, přepne se do blokujícího režimu. To má vliv na volání jako je fgets(), která čtou ze socketu. V neblokujícím režimu volání funkce fgets() vždy předává řízení zpět, zatímco v blokujícím režimu bude čekat na to, až budou na socketu dostupná data.

Tato funkce se dříve jmenovala set_socket_blocking(), ale tento název je nyní zavržený.

socket_set_timeout

(PHP 4 )

socket_set_timeout -- Nastaví časový limit (timeout) socketu

Popis

bool socket_set_timeout ( int socket descriptor, int seconds, int microseconds)

Nastavuje velikost časového limitu socketu daného hodnotou socket descriptor, ve formě součtu sekund (seconds) a mikrosekund (microseconds).

Příklad 1. socket_set_timeout() Příklad

<?php $fp = fsockopen("www.example.com", 80); if(!$fp) { echo "Nelze otevřít\n"; } else { fputs($fp,"GET / HTTP/1.0\n\n"); $start = time(); socket_set_timeout($fp, 2); $res = fread($fp, 2000); var_dump(socket_get_status($fp)); fclose($fp); print $res; } ?>

Tato funkce se dříve jmenovala set_socket_timeout(), ale tento název je nyní zavržený.

Viz také: fsockopen() a fopen().

syslog

(PHP 3, PHP 4 )

syslog -- Vygeneruje zprávu do systémového protokolu

Popis

int syslog ( int priority, string message)

syslog() vygeneruje zprávu do protokolu, která se distribuuje prostřednictvím démona systémového protokolu. priority představuje kombinaci charakteru a úrovně zprávy; hodnoty popisuje následující sekce. Zbývající argument je zpráva, která se má odeslat. Dva znaky ve zprávě (%m) se však nahradí řetězcem chybové zprávy (strerror) odpovídající aktuální hodnotě errno.

Tabulka 1. syslog() Priority (v klesajícím pořádku)

Konstanta	Popis
LOG_EMERG	systém je nepoužitelný
LOG_ALERT	je nutný okamžitý zásah
LOG_CRIT	kritická situace
LOG_ERR	chyba
LOG_WARNING	varování
LOG_NOTICE	normální, avšak významná, zpráva
LOG_INFO	informativní zpráva
LOG_DEBUG	ladicí zpráva

Příklad 1. Použití syslog()

<?php define_syslog_variables(); // otevře syslog, vloží ID procesu a odešle také na standardní chybový // výstup; použije uživatelsky definovaný protokolovací mechanismus openlog("myScripLog", LOG_PID | LOG_PERROR, LOG_LOCAL0); // nějaký kód if (authorized_client()) { // něco udělej } else { // neautorizovaný klient! // zaznamenej pokus o přístup $access = date("Y/m/d H:i:s"); syslog(LOG_WARNING,"Neautorizovaný klient: $access $REMOTE_ADDR ($HTTP_USER_AGENT)"); } closelog(); ?>
Více informací o nastavení uživatelské obsluhy protokolování -- viz unixovou manuálovou stránku syslog.conf(5). Více informací o možnostech a volbách mechanismu syslog najdete (na unixových strojích) v manuálových stránkách pro syslog(3).

Na Windows NT je služba syslog emulována pomocí služby Event Log.

Viz také define_syslog_variables(), openlog() a closelog().

LXVII. Ncurses terminal screen control functions

Varování

What is ncurses?

ncurses (new curses) is a free software emulation of curses in System V Rel 4.0 (and above). It uses terminfo format, supports pads, colors, multiple highlights, form characters and function key mapping.

Platforms

Ncurses is available for the following platforms:

AIX
BeOS
Cygwin
Digital Unix (aka OSF1)
FreeBSD
GNU/Linux
HPUX
IRIX
OS/2
SCO OpenServer
Solaris
SunOS

Requirements

You need the ncurses libraries and headerfiles. Download the latest version from the ftp://ftp.gnu.org/pub/gnu/ncurses/ or from an other GNU-Mirror.

Installation

To get these functions to work, you have to compile the CGI version of PHP with --with-ncurses.

Ncurses predefined constants

Error codes

On error ncurses functions return NCURSES_ERR.

Colors

Tabulka 1. ncurses color constants

constant	meaning
NCURSES_COLOR_BLACK	no color (black)
NCURSES_COLOR_WHITE	white
NCURSES_COLOR_RED	red - supported when terminal is in color mode
NCURSES_COLOR_GREEN	green - supported when terminal is in color mod
NCURSES_COLOR_YELLOW	yellow - supported when terminal is in color mod
NCURSES_COLOR_BLUE	blue - supported when terminal is in color mod
NCURSES_COLOR_CYAN	cyan - supported when terminal is in color mod
NCURSES_COLOR_MAGENTA	magenta - supported when terminal is in color mod

Keys

Tabulka 2. ncurses key constants

constant	meaning
NCURSES_KEY_F0 - NCURSES_KEY_F64	function keys F1 - F64
NCURSES_KEY_DOWN	down arrow
NCURSES_KEY_UP	up arrow
NCURSES_KEY_LEFT	left arrow
NCURSES_KEY_RIGHT	right arrow
NCURSES_KEY_HOME	home key (upward+left arrow)
NCURSES_KEY_BACKSPACE	backspace
NCURSES_KEY_DL	delete line
NCURSES_KEY_IL	insert line
NCURSES_KEY_DC	delete character
NCURSES_KEY_IC	insert char or enter insert mode
NCURSES_KEY_EIC	exit insert char mode
NCURSES_KEY_CLEAR	clear screen
NCURSES_KEY_EOS	clear to end of screen
NCURSES_KEY_EOL	clear to end of line
NCURSES_KEY_SF	scroll one line forward
NCURSES_KEY_SR	scroll one line backward
NCURSES_KEY_NPAGE	next page
NCURSES_KEY_PPAGE	previous page
NCURSES_KEY_STAB	set tab
NCURSES_KEY_CTAB	clear tab
NCURSES_KEY_CATAB	clear all tabs
NCURSES_KEY_SRESET	soft (partial) reset
NCURSES_KEY_RESET	reset or hard reset
NCURSES_KEY_PRINT	print
NCURSES_KEY_LL	lower left
NCURSES_KEY_A1	upper left of keypad
NCURSES_KEY_A3	upper right of keypad
NCURSES_KEY_B2	center of keypad
NCURSES_KEY_C1	lower left of keypad
NCURSES_KEY_C3	lower right of keypad
NCURSES_KEY_BTAB	back tab
NCURSES_KEY_BEG	beginning
NCURSES_KEY_CANCEL	cancel
NCURSES_KEY_CLOSE	close
NCURSES_KEY_COMMAND	cmd (command)
NCURSES_KEY_COPY	copy
NCURSES_KEY_CREATE	create
NCURSES_KEY_END	end
NCURSES_KEY_EXIT	exit
NCURSES_KEY_FIND	find
NCURSES_KEY_HELP	help
NCURSES_KEY_MARK	mark
NCURSES_KEY_MESSAGE	message
NCURSES_KEY_MOVE	move
NCURSES_KEY_NEXT	next
NCURSES_KEY_OPEN	open
NCURSES_KEY_OPTIONS	options
NCURSES_KEY_PREVIOUS	previous
NCURSES_KEY_REDO	redo
NCURSES_KEY_REFERENCE	ref (reference)
NCURSES_KEY_REFRESH	refresh
NCURSES_KEY_REPLACE	replace
NCURSES_KEY_RESTART	restart
NCURSES_KEY_RESUME	resume
NCURSES_KEY_SAVE	save
NCURSES_KEY_SBEG	shiftet beg (beginning)
NCURSES_KEY_SCANCEL	shifted cancel
NCURSES_KEY_SCOMMAND	shifted command
NCURSES_KEY_SCOPY	shifted copy
NCURSES_KEY_SCREATE	shifted create
NCURSES_KEY_SDC	shifted delete char
NCURSES_KEY_SDL	shifted delete line
NCURSES_KEY_SELECT	select
NCURSES_KEY_SEND	shifted end
NCURSES_KEY_SEOL	shifted end of line
NCURSES_KEY_SEXIT	shifted exit
NCURSES_KEY_SFIND	shifted find
NCURSES_KEY_SHELP	shifted help
NCURSES_KEY_SHOME	shifted home
NCURSES_KEY_SIC	shifted input
NCURSES_KEY_SLEFT	shifted left arrow
NCURSES_KEY_SMESSAGE	shifted message
NCURSES_KEY_SMOVE	shifted move
NCURSES_KEY_SNEXT	shifted next
NCURSES_KEY_SOPTIONS	shifted options
NCURSES_KEY_SPREVIOUS	shifted previous
NCURSES_KEY_SPRINT	shifted print
NCURSES_KEY_SREDO	shifted redo
NCURSES_KEY_SREPLACE	shifted replace
NCURSES_KEY_SRIGHT	shifted right arrow
NCURSES_KEY_SRSUME	shifted resume
NCURSES_KEY_SSAVE	shifted save
NCURSES_KEY_SSUSPEND	shifted suspend
NCURSES_KEY_UNDO	undo
NCURSES_KEY_MOUSE	mouse event has occured
NCURSES_KEY_MAX	maximum key value

Mouse

Tabulka 3. mouse constants

Constant	meaning
NCURSES_BUTTON1_RELEASED - NCURSES_BUTTON4_RELEASED	button (1-4) released
NCURSES_BUTTON1_PRESSED - NCURSES_BUTTON4_PRESSED	button (1-4) pressed
NCURSES_BUTTON1_CLICKED - NCURSES_BUTTON4_CLICKED	button (1-4) clicked
NCURSES_BUTTON1_DOUBLE_CLICKED - NCURSES_BUTTON4_DOUBLE_CLICKED	button (1-4) double clicked
NCURSES_BUTTON1_TRIPLE_CLICKED - NCURSES_BUTTON4_TRIPLE_CLICKED	button (1-4) triple clicked
NCURSES_BUTTON_CTRL	ctrl pressed during click
NCURSES_BUTTON_SHIFT	shift pressed during click
NCURSES_BUTTON_ALT	alt pressed during click
NCURSES_ALL_MOUSE_EVENTS	report all mouse events
NCURSES_REPORT_MOUSE_POSITION	report mouse position

Obsah
ncurses_addch -- Add character at current position and advance cursor
ncurses_addchnstr -- Add attributed string with specified length at current position
ncurses_addchstr -- Add attributed string at current position
ncurses_addnstr -- Add string with specified length at current position
ncurses_addstr -- Output text at current position
ncurses_assume_default_colors -- Define default colors for color 0
ncurses_attroff -- Turn off the given attributes
ncurses_attron -- Turn on the given attributes
ncurses_attrset -- Set given attributes
ncurses_baudrate -- Returns baudrate of terminal
ncurses_beep -- Let the terminal beep
ncurses_bkgd -- Set background property for terminal screen
ncurses_bkgdset -- Control screen background
ncurses_border -- Draw a border around the screen using attributed characters
ncurses_can_change_color -- Check if we can change terminals colors
ncurses_cbreak -- Switch of input buffering
ncurses_clear -- Clear screen
ncurses_clrtobot -- Clear screen from current position to bottom
ncurses_clrtoeol -- Clear screen from current position to end of line
ncurses_color_set -- Set fore- and background color
ncurses_curs_set -- Set cursor state
ncurses_def_prog_mode -- Saves terminals (program) mode
ncurses_def_shell_mode -- Saves terminals (shell) mode
ncurses_define_key -- Define a keycode
ncurses_delay_output -- Delay output on terminal using padding characters
ncurses_delch -- Delete character at current position, move rest of line left
ncurses_deleteln -- Delete line at current position, move rest of screen up
ncurses_delwin -- Delete a ncurses window
ncurses_doupdate -- Write all prepared refreshes to terminal
ncurses_echo -- Activate keyboard input echo
ncurses_echochar -- Single character output including refresh
ncurses_end -- Stop using ncurses, clean up the screen
ncurses_erase -- Erase terminal screen
ncurses_erasechar -- Returns current erase character
ncurses_filter --
ncurses_flash -- Flash terminal screen (visual bell)
ncurses_flushinp -- Flush keyboard input buffer
ncurses_getch -- Read a character from keyboard
ncurses_getmouse -- Reads mouse event
ncurses_halfdelay -- Put terminal into halfdelay mode
ncurses_has_colors -- Check if terminal has colors
ncurses_has_ic -- Check for insert- and delete-capabilities
ncurses_has_il -- Check for line insert- and delete-capabilities
ncurses_has_key -- Check for presence of a function key on terminal keyboard
ncurses_hline -- Draw a horizontal line at current position using an attributed character and max. n characters long
ncurses_inch -- Get character and attribute at current position
ncurses_init_color -- Set new RGB value for color
ncurses_init_pair -- Allocate a color pair
ncurses_init -- Initialize ncurses
ncurses_insch -- Insert character moving rest of line including character at current position
ncurses_insdelln -- Insert lines before current line scrolling down (negative numbers delete and scroll up)
ncurses_insertln -- Insert a line, move rest of screen down
ncurses_insstr -- Insert string at current position, moving rest of line right
ncurses_instr -- Reads string from terminal screen
ncurses_isendwin -- Ncurses is in endwin mode, normal screen output may be performed
ncurses_keyok -- Enable or disable a keycode
ncurses_killchar -- Returns current line kill character
ncurses_longname -- Returns terminals description
ncurses_mouseinterval -- Set timeout for mouse button clicks
ncurses_mousemask -- Sets mouse options
ncurses_move -- Move output position
ncurses_mvaddch -- Move current position and add character
ncurses_mvaddchnstr -- Move position and add attrributed string with specified length
ncurses_mvaddchstr -- Move position and add attributed string
ncurses_mvaddnstr -- Move position and add string with specified length
ncurses_mvaddstr -- Move position and add string
ncurses_mvcur -- Move cursor immediately
ncurses_mvdelch -- Move position and delete character, shift rest of line left
ncurses_mvgetch -- Move position and get character at new position
ncurses_mvhline -- Set new position and draw a horizontal line using an attributed character and max. n characters long
ncurses_mvinch -- Move position and get attributed character at new position
ncurses_mvvline -- Set new position and draw a vertical line using an attributed character and max. n characters long
ncurses_mvwaddstr -- Add string at new position in window
ncurses_napms -- Sleep
ncurses_newwin -- Create a new window
ncurses_nl -- Translate newline and carriage return / line feed
ncurses_nocbreak -- Switch terminal to cooked mode
ncurses_noecho -- Switch off keyboard input echo
ncurses_nonl -- Do not translate newline and carriage return / line feed
ncurses_noqiflush -- Do not flush on signal characters
ncurses_noraw -- Switch terminal out of raw mode
ncurses_putp --
ncurses_qiflush -- Flush on signal characters
ncurses_raw -- Switch terminal into raw mode
ncurses_refresh -- Refresh screen
ncurses_resetty -- Restores saved terminal state
ncurses_savetty -- Saves terminal state
ncurses_scr_dump -- Dump screen content to file
ncurses_scr_init -- Initialize screen from file dump
ncurses_scr_restore -- Restore screen from file dump
ncurses_scr_set -- Inherit screen from file dump
ncurses_scrl -- Scroll window content up or down without changing current position
ncurses_slk_attr -- Returns current soft label key attribute
ncurses_slk_attroff --
ncurses_slk_attron --
ncurses_slk_attrset --
ncurses_slk_clear -- Clears soft labels from screen
ncurses_slk_color -- Sets color for soft label keys
ncurses_slk_init -- Initializes soft label key functions
ncurses_slk_noutrefresh -- Copies soft label keys to virtual screen
ncurses_slk_refresh -- Copies soft label keys to screen
ncurses_slk_restore -- Restores soft label keys
ncurses_slk_touch -- Fources output when ncurses_slk_noutrefresh is performed
ncurses_standend -- Stop using 'standout' attribute
ncurses_standout -- Start using 'standout' attribute
ncurses_start_color -- Start using colors
ncurses_termattrs -- Returns a logical OR of all attribute flags supported by terminal
ncurses_termname -- Returns terminals (short)-name
ncurses_timeout -- Set timeout for special key sequences
ncurses_typeahead -- Specify different filedescriptor for typeahead checking
ncurses_ungetch -- Put a character back into the input stream
ncurses_ungetmouse -- Pushes mouse event to queue
ncurses_use_default_colors -- Assign terminal default colors to color id -1
ncurses_use_env -- Control use of environment information about terminal size
ncurses_use_extended_names -- Control use of extended names in terminfo descriptions
ncurses_vidattr --
ncurses_vline -- Draw a vertical line at current position using an attributed character and max. n characters long
ncurses_wrefresh -- Refresh window on terminal screen

ncurses_cbreak() returns TRUE or NCURSES_ERR if any error occured.

ncurses_clear

(PHP 4 >= 4.1.0)

ncurses_clear -- Clear screen

Description

bool ncurses_clear ( void)

bool ncurses_def_shell_mode ( void)

bool ncurses_echo ( void)

bool ncurses_getmouse ( array mevent)

Varování

ncurses_getmouse() reads mouse event out of queue. Function ncurses_getmouse() will return ;FALSE if a mouse event is actually visible in the given window, otherwise it will return TRUE. Event options will be delivered in parameter mevent, which has to be an array, passed by reference (see example below). On success an associative array with following keys will be delivered:

"id" : Id to distinguish multiple devices
"x" : screen relative x-position in character cells
"y" : screen relative y-position in character cells
"z" : currently not supported
"mmask" : Mouse action

Varování

Function ncurses_mousemask() will set mouse events to be reported. By default no mouse events will be reported. The function ncurses_mousemask() will return a mask to indicated which of the in parameter newmask specified mouse events can be reported. On complete failure, it returns 0. In parameter oldmask, which is passed by reference ncurses_mousemask() returns the previous value of mouse event mask. Mouse events are represented bei NCURSES_KEY_MOUSE in the ncurses_wgetch() input stream. To read the event data and pop the event of of queue, call ncurses_getmouse().

As a side effect, setting a zero mousemask in newmask turns off the mouse pointer. Setting a non zero value turns mouse pointer on.

mouse mask options can be set with the following predefined constants:

NCURSES_BUTTON1_PRESSED
NCURSES_BUTTON1_RELEASED
NCURSES_BUTTON1_CLICKED
NCURSES_BUTTON1_DOUBLE_CLICKED
NCURSES_BUTTON1_TRIPLE_CLICKED
NCURSES_BUTTON2_PRESSED
NCURSES_BUTTON2_RELEASED
NCURSES_BUTTON2_CLICKED
NCURSES_BUTTON2_DOUBLE_CLICKED
NCURSES_BUTTON2_TRIPLE_CLICKED
NCURSES_BUTTON3_PRESSED
NCURSES_BUTTON3_RELEASED
NCURSES_BUTTON3_CLICKED
NCURSES_BUTTON3_DOUBLE_CLICKED
NCURSES_BUTTON3_TRIPLE_CLICKED
NCURSES_BUTTON4_PRESSED
NCURSES_BUTTON4_RELEASED
NCURSES_BUTTON4_CLICKED
NCURSES_BUTTON4_DOUBLE_CLICKED
NCURSES_BUTTON4_TRIPLE_CLICKED
NCURSES_BUTTON_SHIFT>
NCURSES_BUTTON_CTRL
NCURSES_BUTTON_ALT
NCURSES_ALL_MOUSE_EVENTS
NCURSES_REPORT_MOUSE_POSITION

Varování

ncurses_getmouse() pushes a KEY_MOUSE event onto the unput queue and associates with this event the given state sata and screen-relative character cell coordinates, specified in mevent. Event options will be specified in associative array mevent:

"id" : Id to distinguish multiple devices
"x" : screen relative x-position in character cells
"y" : screen relative y-position in character cells
"z" : currently not supported
"mmask" : Mouse action

Name	Default	Changeable
odbc.default_db *	NULL	PHP_INI_ALL
odbc.default_user *	NULL	PHP_INI_ALL
odbc.default_pw *	NULL	PHP_INI_ALL
odbc.allow_persistent	"1"	PHP_INI_SYSTEM
odbc.check_persistent	"1"	PHP_INI_SYSTEM
odbc.max_persistent	"-1"	PHP_INI_SYSTEM
odbc.max_links	"-1"	PHP_INI_SYSTEM
odbc.defaultlrl	"4096"	PHP_INI_ALL
odbc.defaultbinmode	"1"	PHP_INI_ALL

Poznámka: Entries marked with * are not implemented yet.

For further details and definition of the PHP_INI_* constants see ini_set().

Here is a short explanation of the configuration directives.

odbc.default_db string: ODBC data source to use if none is specified in odbc_connect() or odbc_pconnect().
odbc.default_user string: User name to use if none is specified in odbc_connect() or odbc_pconnect().
odbc.default_pw string: Password to use if none is specified in odbc_connect() or odbc_pconnect().
odbc.allow_persistent boolean: Whether to allow persistent ODBC connections.
odbc.check_persistent boolean: Check that a connection is still valid before reuse.
odbc.max_persistent integer: The maximum number of persistent ODBC connections per process.
odbc.max_links integer: The maximum number of ODBC connections per process, including persistent connections.
odbc.defaultlrl integer: Handling of LONG fields. Specifies the number of bytes returned to variables.
odbc.defaultbinmode integer: Handling of binary data.

Resource types

Toto rezšíření nemá definován žádný typ prostředku (resource).

Predefined constants

Toto rozšíření nemá definovány žádné konstanty.

Obsah
odbc_autocommit -- Toggle autocommit behaviour
odbc_binmode -- Handling of binary column data
odbc_close_all -- Close all ODBC connections
odbc_close -- Close an ODBC connection
odbc_columnprivileges -- Returns a result identifier that can be used to fetch a list of columns and associated privileges
odbc_columns -- Lists the column names in specified tables. Returns a result identifier containing the information.
odbc_commit -- Commit an ODBC transaction
odbc_connect -- Connect to a datasource
odbc_cursor -- Get cursorname
odbc_do -- Synonym for odbc_exec()
odbc_error -- Get the last error code
odbc_errormsg -- Get the last error message
odbc_exec -- Prepare and execute a SQL statement
odbc_execute -- Execute a prepared statement
odbc_fetch_array -- Fetch a result row as an associative array
odbc_fetch_into -- Fetch one result row into array
odbc_fetch_object -- Fetch a result row as an object
odbc_fetch_row -- Fetch a row
odbc_field_len -- Get the length (precision) of a field
odbc_field_name -- Get the columnname
odbc_field_num -- Return column number
odbc_field_precision -- Synonym for odbc_field_len()
odbc_field_scale -- Get the scale of a field
odbc_field_type -- Datatype of a field
odbc_foreignkeys -- Returns a list of foreign keys in the specified table or a list of foreign keys in other tables that refer to the primary key in the specified table
odbc_free_result -- Free resources associated with a result
odbc_gettypeinfo -- Returns a result identifier containing information about data types supported by the data source.
odbc_longreadlen -- Handling of LONG columns
odbc_next_result -- Checks if multiple results are avaiable
odbc_num_fields -- Number of columns in a result
odbc_num_rows -- Number of rows in a result
odbc_pconnect -- Open a persistent database connection
odbc_prepare -- Prepares a statement for execution
odbc_primarykeys -- Returns a result identifier that can be used to fetch the column names that comprise the primary key for a table
odbc_procedurecolumns -- Retrieve information about parameters to procedures
odbc_procedures -- Get the list of procedures stored in a specific data source. Returns a result identifier containing the information.
odbc_result_all -- Print result as HTML table
odbc_result -- Get result data
odbc_rollback -- Rollback a transaction
odbc_setoption -- Adjust ODBC settings. Returns FALSE if an error occurs, otherwise TRUE.
odbc_specialcolumns -- Returns either the optimal set of columns that uniquely identifies a row in the table or columns that are automatically updated when any value in the row is updated by a transaction
odbc_statistics -- Retrieve statistics about a table
odbc_tableprivileges -- Lists tables and the privileges associated with each table
odbc_tables -- Get the list of table names stored in a specific data source. Returns a result identifier containing the information.

odbc_autocommit

(PHP 3>= 3.0.6, PHP 4 )

odbc_autocommit -- Toggle autocommit behaviour

Description

bool odbc_autocommit ( resource connection_id [, bool OnOff])

Without the OnOff parameter, this function returns auto-commit status for connection_id. TRUE is returned if auto-commit is on, FALSE if it is off or an error occurs.

If OnOff is TRUE, auto-commit is enabled, if it is FALSE auto-commit is disabled. Returns TRUE on success, FALSE on failure.

By default, auto-commit is on for a connection. Disabling auto-commit is equivalent with starting a transaction.

odbc_binmode

(PHP 3>= 3.0.6, PHP 4 )

odbc_binmode -- Handling of binary column data

Description

int odbc_binmode ( resource result_id, int mode)

(ODBC SQL types affected: BINARY, VARBINARY, LONGVARBINARY)

ODBC_BINMODE_PASSTHRU: Passthru BINARY data
ODBC_BINMODE_RETURN: Return as is
ODBC_BINMODE_CONVERT: Convert to char and return

When binary SQL data is converted to character C data, each byte (8 bits) of source data is represented as two ASCII characters. These characters are the ASCII character representation of the number in its hexadecimal form. For example, a binary 00000001 is converted to "01" and a binary 11111111 is converted to "FF".

Tabulka 1. LONGVARBINARY handling

binmode	longreadlen	result
ODBC_BINMODE_PASSTHRU	0	passthru
ODBC_BINMODE_RETURN	0	passthru
ODBC_BINMODE_CONVERT	0	passthru
ODBC_BINMODE_PASSTHRU	0	passthru
ODBC_BINMODE_PASSTHRU	>0	passthru
ODBC_BINMODE_RETURN	>0	return as is
ODBC_BINMODE_CONVERT	>0	return as char

If odbc_fetch_into() is used, passthru means that an empty string is returned for these columns.

If result_id is 0, the settings apply as default for new results.

Poznámka: Default for longreadlen is 4096 and binmode defaults to ODBC_BINMODE_RETURN. Handling of binary long columns is also affected by odbc_longreadlen()

odbc_close_all

(PHP 3>= 3.0.6, PHP 4 )

odbc_close_all -- Close all ODBC connections

Description

void odbc_close_all ( void)

odbc_close_all() will close down all connections to database server(s).

Poznámka: This function will fail if there are open transactions on a connection. This connection will remain open in this case.

odbc_close

(PHP 3>= 3.0.6, PHP 4 )

odbc_close -- Close an ODBC connection

Description

void odbc_close ( resource connection_id)

odbc_close() will close down the connection to the database server associated with the given connection identifier.

Poznámka: This function will fail if there are open transactions on this connection. The connection will remain open in this case.

odbc_columnprivileges

(PHP 4 )

odbc_columnprivileges -- Returns a result identifier that can be used to fetch a list of columns and associated privileges

Description

int odbc_columnprivileges ( resource connection_id [, string qualifier [, string owner [, string table_name [, string column_name]]]])

Lists columns and associated privileges for the given table. Returns an ODBC result identifier or FALSE on failure.

The result set has the following columns:

TABLE_QUALIFIER
TABLE_OWNER
TABLE_NAME
GRANTOR
GRANTEE
PRIVILEGE
IS_GRANTABLE

The result set is ordered by TABLE_QUALIFIER, TABLE_OWNER and TABLE_NAME.

The column_name argument accepts search patterns ('%' to match zero or more characters and '_' to match a single character).

odbc_columns

(PHP 4 )

odbc_columns -- Lists the column names in specified tables. Returns a result identifier containing the information.

Description

int odbc_columns ( resource connection_id [, string qualifier [, string owner [, string table_name [, string column_name]]]])

Lists all columns in the requested range. Returns an ODBC result identifier or FALSE on failure.

The result set has the following columns:

TABLE_QUALIFIER
TABLE_OWNER
TABLE_NAME
COLUMN_NAME
DATA_TYPE
TYPE_NAME
PRECISION
LENGTH
SCALE
RADIX
NULLABLE
REMARKS

The result set is ordered by TABLE_QUALIFIER, TABLE_OWNER and TABLE_NAME.

The owner, table_name and column_name arguments accept search patterns ('%' to match zero or more characters and '_' to match a single character).

See also odbc_columnprivileges() to retrieve associated privileges.

odbc_commit

(PHP 3>= 3.0.6, PHP 4 )

odbc_commit -- Commit an ODBC transaction

Description

bool odbc_commit ( resource connection_id)

Returns: TRUE on success, FALSE on failure. All pending transactions on connection_id are committed.

odbc_connect

(PHP 3>= 3.0.6, PHP 4 )

odbc_connect -- Connect to a datasource

Description

resource odbc_connect ( string dsn, string user, string password [, int cursor_type])

Returns an ODBC connection id or 0 (FALSE) on error.

The connection id returned by this functions is needed by other ODBC functions. You can have multiple connections open at once. The optional fourth parameter sets the type of cursor to be used for this connection. This parameter is not normally needed, but can be useful for working around problems with some ODBC drivers.

With some ODBC drivers, executing a complex stored procedure may fail with an error similar to: "Cannot open a cursor on a stored procedure that has anything other than a single select statement in it". Using SQL_CUR_USE_ODBC may avoid that error. Also, some drivers don't support the optional row_number parameter in odbc_fetch_row(). SQL_CUR_USE_ODBC might help in that case, too.

The following constants are defined for cursortype:

SQL_CUR_USE_IF_NEEDED
SQL_CUR_USE_ODBC
SQL_CUR_USE_DRIVER
SQL_CUR_DEFAULT

Returns a six-digit ODBC state, or an empty string if there has been no errors. If connection_id is specified, the last state of that connection is returned, else the last state of any connection is returned.

See also: odbc_errormsg() and odbc_exec().

odbc_errormsg

(PHP 4 >= 4.0.5)

odbc_errormsg -- Get the last error message

Description

string odbc_errormsg ( [resource connection_id])

Returns a string containing the last ODBC error message, or an empty string if there has been no errors. If connection_id is specified, the last state of that connection is returned, else the last state of any connection is returned.

See also: odbc_error() and odbc_exec().

odbc_exec

(PHP 3>= 3.0.6, PHP 4 )

odbc_exec -- Prepare and execute a SQL statement

Description

resource odbc_exec ( resource connection_id, string query_string)

Returns FALSE on error. Returns an ODBC result identifier if the SQL command was executed successfully.

odbc_exec() will send an SQL statement to the database server specified by connection_id. This parameter must be a valid identifier returned by odbc_connect() or odbc_pconnect().

See also: odbc_prepare() and odbc_execute() for multiple execution of SQL statements.

odbc_execute

(PHP 3>= 3.0.6, PHP 4 )

odbc_execute -- Execute a prepared statement

Description

resource odbc_execute ( resource result_id [, array parameters_array])

Executes a statement prepared with odbc_prepare(). Returns TRUE on successful execution; FALSE otherwise. The array parameters_array only needs to be given if you really have parameters in your statement.

Parameters in parameter_array will be substituted for placeholders in the prepared statement in order.

Any parameters in parameter_array which start and end with single quotes will be taken as the name of a file to read and send to the database server as the data for the appropriate placeholder.

Poznámka: As of PHP 4.1.1, this file reading functionality has the following restrictions:

File reading is not subject to any safe mode or safe mode restrictions. This is fixed in PHP 4.2.0.

Remote files are not supported.

If you wish to store a string which actually begins and ends with single quotes, you must escape them or add a space or other non-single-quote character to the beginning or end of the parameter, which will prevent the parameter's being taken as a file name. If this is not an option, then you must use another mechanism to store the string, such as executing the query directly with odbc_exec()).

odbc_fetch_array

(PHP 4 >= 4.0.2)

odbc_fetch_array -- Fetch a result row as an associative array

Description

array odbc_fetch_array ( resource result [, int rownumber])

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

odbc_fetch_into

(PHP 3>= 3.0.6, PHP 4 )

odbc_fetch_into -- Fetch one result row into array

Description

bool odbc_fetch_into ( resource result_id [, int rownumber, array result_array])

resource odbc_fetch_into ( resource result_id, array result_array [, int rownumber])

Returns the number of columns in the result; FALSE on error. result_array must be passed by reference, but it can be of any type since it will be converted to type array. The array will contain the column values starting at array index 0.

As of PHP 4.0.5 the result_array does not need to be passed by reference any longer.

As of PHP 4.0.6 the rownumber cannot be passed as a constant, but rather as a variable.

As of PHP 4.2.0 the result_array and rownumber have been swapped. This allows the rownumber to be a constant again. This change will also be the last one to this function.

Příklad 1. odbc_fetch_into() pre 4.0.6 example

$rc = odbc_fetch_into($res_id, $my_array);

or

$rc = odbc_fetch_into($res_id, $row, $my_array); $rc = odbc_fetch_into($res_id, 1, $my_array);

Příklad 2. odbc_fetch_into() 4.0.6 example

$rc = odbc_fetch_into($res_id, $my_array);

or

$row = 1; $rc = odbc_fetch_into($res_id, $row, $my_array);

Příklad 3. odbc_fetch_into() 4.2.0 example

$rc = odbc_fetch_into($res_id, $my_array);

or

$rc = odbc_fetch_into($res_id,$my_array, 2);

odbc_fetch_object

(PHP 4 >= 4.0.2)

odbc_fetch_object -- Fetch a result row as an object

Description

object odbc_fetch_object ( resource result [, int rownumber])

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

odbc_fetch_row

(PHP 3>= 3.0.6, PHP 4 )

odbc_fetch_row -- Fetch a row

Description

bool odbc_fetch_row ( resource result_id [, int row_number])

If odbc_fetch_row() was succesful (there was a row), TRUE is returned. If there are no more rows, FALSE is returned.

odbc_fetch_row() fetches a row of the data that was returned by odbc_do() / odbc_exec(). After odbc_fetch_row() is called, the fields of that row can be accessed with odbc_result().

If row_number is not specified, odbc_fetch_row() will try to fetch the next row in the result set. Calls to odbc_fetch_row() with and without row_number can be mixed.

To step through the result more than once, you can call odbc_fetch_row() with row_number 1, and then continue doing odbc_fetch_row() without row_number to review the result. If a driver doesn't support fetching rows by number, the row_number parameter is ignored.

odbc_field_len

(PHP 3>= 3.0.6, PHP 4 )

odbc_field_len -- Get the length (precision) of a field

Description

int odbc_field_len ( resource result_id, int field_number)

odbc_field_len() will return the length of the field referecend by number in the given ODBC result identifier. Field numbering starts at 1.

See also: odbc_field_scale() to get the scale of a floating point number.

odbc_foreignkeys() retrieves information about foreign keys. Returns an ODBC result identifier or FALSE on failure.

The result set has the following columns:

PKTABLE_QUALIFIER
PKTABLE_OWNER
PKTABLE_NAME
PKCOLUMN_NAME
FKTABLE_QUALIFIER
FKTABLE_OWNER
FKTABLE_NAME
FKCOLUMN_NAME
KEY_SEQ
UPDATE_RULE
DELETE_RULE
FK_NAME
PK_NAME

If pk_table contains a table name, odbc_foreignkeys() returns a result set containing the primary key of the specified table and all of the foreign keys that refer to it.

If fk_table contains a table name, odbc_foreignkeys() returns a result set containing all of the foreign keys in the specified table and the primary keys (in other tables) to which they refer.

If both pk_table and fk_table contain table names, odbc_foreignkeys() returns the foreign keys in the table specified in fk_table that refer to the primary key of the table specified in pk_table. This should be one key at most.

odbc_free_result

(PHP 3>= 3.0.6, PHP 4 )

odbc_free_result -- Free resources associated with a result

Description

bool odbc_free_result ( resource result_id)

Always returns TRUE.

odbc_free_result() only needs to be called if you are worried about using too much memory while your script is running. All result memory will automatically be freed when the script is finished. But, if you are sure you are not going to need the result data anymore in a script, you may call odbc_free_result(), and the memory associated with result_id will be freed.

Poznámka: If auto-commit is disabled (see odbc_autocommit()) and you call odbc_free_result() before commiting, all pending transactions are rolled back.

odbc_gettypeinfo

(PHP 4 )

odbc_gettypeinfo -- Returns a result identifier containing information about data types supported by the data source.

Description

int odbc_gettypeinfo ( resource connection_id [, int data_type])

Retrieves information about data types supported by the data source. Returns an ODBC result identifier or FALSE on failure. The optional argument data_type can be used to restrict the information to a single data type.

The result set has the following columns:

TYPE_NAME
DATA_TYPE
PRECISION
LITERAL_PREFIX
LITERAL_SUFFIX
CREATE_PARAMS
NULLABLE
CASE_SENSITIVE
SEARCHABLE
UNSIGNED_ATTRIBUTE
MONEY
AUTO_INCREMENT
LOCAL_TYPE_NAME
MINIMUM_SCALE
MAXIMUM_SCALE

odbc_num_rows

(PHP 3>= 3.0.6, PHP 4 )

odbc_num_rows -- Number of rows in a result

Description

int odbc_num_rows ( resource result_id)

odbc_num_rows() will return the number of rows in an ODBC result. This function will return -1 on error. For INSERT, UPDATE and DELETE statements odbc_num_rows() returns the number of rows affected. For a SELECT clause this can be the number of rows available.

Note: Using odbc_num_rows() to determine the number of rows available after a SELECT will return -1 with many drivers.

odbc_pconnect

(PHP 3>= 3.0.6, PHP 4 )

odbc_pconnect -- Open a persistent database connection

Description

int odbc_pconnect ( string dsn, string user, string password [, int cursor_type])

Returns an ODBC connection id or 0 (FALSE) on error. This function is much like odbc_connect(), except that the connection is not really closed when the script has finished. Future requests for a connection with the same dsn, user, password combination (via odbc_connect() and odbc_pconnect()) can reuse the persistent connection.

Poznámka: Persistent connections have no effect if PHP is used as a CGI program.

For information about the optional cursor_type parameter see the odbc_connect() function. For more information on persistent connections, refer to the PHP FAQ.

odbc_prepare

(PHP 3>= 3.0.6, PHP 4 )

odbc_prepare -- Prepares a statement for execution

Description

resource odbc_prepare ( resource connection_id, string query_string)

Returns FALSE on error.

Returns an ODBC result identifier if the SQL command was prepared successfully. The result identifier can be used later to execute the statement with odbc_execute().

odbc_primarykeys

(PHP 4 )

odbc_primarykeys -- Returns a result identifier that can be used to fetch the column names that comprise the primary key for a table

Description

resource odbc_primarykeys ( resource connection_id, string qualifier, string owner, string table)

Returns the column names that comprise the primary key for a table. Returns an ODBC result identifier or FALSE on failure.

The result set has the following columns:

TABLE_QUALIFIER
TABLE_OWNER
TABLE_NAME
COLUMN_NAME
KEY_SEQ
PK_NAME

odbc_procedurecolumns

(PHP 4 )

odbc_procedurecolumns -- Retrieve information about parameters to procedures

Description

resource odbc_procedurecolumns ( resource connection_id [, string qualifier [, string owner [, string proc [, string column]]]])

Returns the list of input and output parameters, as well as the columns that make up the result set for the specified procedures. Returns an ODBC result identifier or FALSE on failure.

The result set has the following columns:

PROCEDURE_QUALIFIER
PROCEDURE_OWNER
PROCEDURE_NAME
COLUMN_NAME
COLUMN_TYPE
DATA_TYPE
TYPE_NAME
PRECISION
LENGTH
SCALE
RADIX
NULLABLE
REMARKS

The result set is ordered by PROCEDURE_QUALIFIER, PROCEDURE_OWNER, PROCEDURE_NAME and COLUMN_TYPE.

The owner, proc and column arguments accept search patterns ('%' to match zero or more characters and '_' to match a single character).

odbc_procedures

(PHP 4 )

odbc_procedures -- Get the list of procedures stored in a specific data source. Returns a result identifier containing the information.

Description

resource odbc_procedures ( resource connection_id [, string qualifier [, string owner [, string name]]])

Lists all procedures in the requested range. Returns an ODBC result identifier or FALSE on failure.

The result set has the following columns:

PROCEDURE_QUALIFIER
PROCEDURE_OWNER
PROCEDURE_NAME
NUM_INPUT_PARAMS
NUM_OUTPUT_PARAMS
NUM_RESULT_SETS
REMARKS
PROCEDURE_TYPE

Description

int odbc_rollback ( resource connection_id)

Rolls back all pending statements on connection_id. Returns TRUE on success, FALSE on failure.

odbc_setoption

(PHP 3>= 3.0.6, PHP 4 )

odbc_setoption -- Adjust ODBC settings. Returns FALSE if an error occurs, otherwise TRUE.

Description

int odbc_setoption ( resource id, int function, int option, int param)

This function allows fiddling with the ODBC options for a particular connection or query result. It was written to help find work arounds to problems in quirky ODBC drivers. You should probably only use this function if you are an ODBC programmer and understand the effects the various options will have. You will certainly need a good ODBC reference to explain all the different options and values that can be used. Different driver versions support different options.

Because the effects may vary depending on the ODBC driver, use of this function in scripts to be made publicly available is strongly discouraged. Also, some ODBC options are not available to this function because they must be set before the connection is established or the query is prepared. However, if on a particular job it can make PHP work so your boss doesn't tell you to use a commercial product, that's all that really matters.

id is a connection id or result id on which to change the settings.For SQLSetConnectOption(), this is a connection id. For SQLSetStmtOption(), this is a result id.

Function is the ODBC function to use. The value should be 1 for SQLSetConnectOption() and 2 for SQLSetStmtOption().

Parameter option is the option to set.

Parameter param is the value for the given option.

Příklad 1. ODBC Setoption Examples

// 1. Option 102 of SQLSetConnectOption() is SQL_AUTOCOMMIT. // Value 1 of SQL_AUTOCOMMIT is SQL_AUTOCOMMIT_ON. // This example has the same effect as // odbc_autocommit($conn, true); odbc_setoption ($conn, 1, 102, 1); // 2. Option 0 of SQLSetStmtOption() is SQL_QUERY_TIMEOUT. // This example sets the query to timeout after 30 seconds. $result = odbc_prepare ($conn, $sql); odbc_setoption ($result, 2, 0, 30); odbc_execute ($result);

odbc_specialcolumns

(PHP 4 )

odbc_specialcolumns -- Returns either the optimal set of columns that uniquely identifies a row in the table or columns that are automatically updated when any value in the row is updated by a transaction

Description

resource odbc_specialcolumns ( resource connection_id, int type, string qualifier, string owner, string table, int scope, int nullable)

When the type argument is SQL_BEST_ROWID, odbc_specialcolumns() returns the column or columns that uniquely identify each row in the table.

When the type argument is SQL_ROWVER, odbc_specialcolumns() returns the optimal column or set of columns that, by retrieving values from the column or columns, allows any row in the specified table to be uniquely identified.

Returns an ODBC result identifier or FALSE on failure.

The result set has the following columns:

SCOPE
COLUMN_NAME
DATA_TYPE
TYPE_NAME
PRECISION
LENGTH
SCALE
PSEUDO_COLUMN

The result set is ordered by SCOPE.

odbc_statistics

(PHP 4 )

odbc_statistics -- Retrieve statistics about a table

Description

resource odbc_statistics ( resource connection_id, string qualifier, string owner, string table_name, int unique, int accuracy)

Get statistics about a table and it's indexes. Returns an ODBC result identifier or FALSE on failure.

The result set has the following columns:

TABLE_QUALIFIER
TABLE_OWNER
TABLE_NAME
NON_UNIQUE
INDEX_QUALIFIER
INDEX_NAME
TYPE
SEQ_IN_INDEX
COLUMN_NAME
COLLATION
CARDINALITY
PAGES
FILTER_CONDITION

The result set is ordered by NON_UNIQUE, TYPE, INDEX_QUALIFIER, INDEX_NAME and SEQ_IN_INDEX.

odbc_tableprivileges

(PHP 4 )

odbc_tableprivileges -- Lists tables and the privileges associated with each table

Description

int odbc_tableprivileges ( resource connection_id [, string qualifier [, string owner [, string name]]])

Lists tables in the requested range and the privileges associated with each table. Returns an ODBC result identifier or FALSE on failure.

The result set has the following columns:

TABLE_QUALIFIER
TABLE_OWNER
TABLE_NAME
GRANTOR
GRANTEE
PRIVILEGE
IS_GRANTABLE

The result set is ordered by TABLE_QUALIFIER, TABLE_OWNER and TABLE_NAME.

The owner and name arguments accept search patterns ('%' to match zero or more characters and '_' to match a single character).

odbc_tables

(PHP 3>= 3.0.17, PHP 4 )

odbc_tables -- Get the list of table names stored in a specific data source. Returns a result identifier containing the information.

Description

int odbc_tables ( resource connection_id [, string qualifier [, string owner [, string name [, string types]]]])

Lists all tables in the requested range. Returns an ODBC result identifier or FALSE on failure.

The result set has the following columns:

TABLE_QUALIFIER
TABLE_OWNER
TABLE_NAME
TABLE_TYPE
REMARKS

The result set is ordered by TABLE_TYPE, TABLE_QUALIFIER, TABLE_OWNER and TABLE_NAME.

The owner and name arguments accept search patterns ('%' to match zero or more characters and '_' to match a single character).

To support enumeration of qualifiers, owners, and table types, the following special semantics for the qualifier, owner, name, and table_type are available:

If qualifier is a single percent character (%) and owner and name are empty strings, then the result set contains a list of valid qualifiers for the data source. (All columns except the TABLE_QUALIFIER column contain NULLs.)
If owner is a single percent character (%) and qualifier and name are empty strings, then the result set contains a list of valid owners for the data source. (All columns except the TABLE_OWNER column contain NULLs.)
If table_type is a single percent character (%) and qualifier, owner and name are empty strings, then the result set contains a list of valid table types for the data source. (All columns except the TABLE_TYPE column contain NULLs.)

If table_type is not an empty string, it must contain a list of comma-separated values for the types of interest; each value may be enclosed in single quotes (') or unquoted. For example, "'TABLE','VIEW'" or "TABLE, VIEW". If the data source does not support a specified table type, odbc_tables() does not return any results for that type.

See also odbc_tableprivileges() to retrieve associated privileges.

LXX. Oracle 8 functions

These functions allow you to access Oracle8 and Oracle7 databases. It uses the Oracle8 Call-Interface (OCI8). You will need the Oracle8 client libraries to use this extension.

This extension is more flexible than the standard Oracle extension. It supports binding of global and local PHP variables to Oracle placeholders, has full LOB, FILE and ROWID support and allows you to use user-supplied define variables.

Before using this extension, make sure that you have set up your Oracle environment variables properly for the Oracle user, as well as your web daemon user. The variables you might need to set are as follows:

ORACLE_HOME
ORACLE_SID
LD_PRELOAD
LD_LIBRARY_PATH
NLS_LANG
ORA_NLS33

After setting up the environment variables for your webserver user, be sure to also add the webserver user (nobody, www) to the oracle group.

If your webserver doesn't start or crashes at startup: Check that Apache is linked with the pthread library:
# ldd /www/apache/bin/httpd 
    libpthread.so.0 => /lib/libpthread.so.0 (0x4001c000)
    libm.so.6 => /lib/libm.so.6 (0x4002f000)
    libcrypt.so.1 => /lib/libcrypt.so.1 (0x4004c000)
    libdl.so.2 => /lib/libdl.so.2 (0x4007a000)
    libc.so.6 => /lib/libc.so.6 (0x4007e000)
    /lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x40000000)
If the libpthread is not listed you have to reinstall Apache:
# cd /usr/src/apache_1.3.xx
# make clean
# LIBS=-lpthread ./config.status
# make
# make install
Please note that on some systems like UnixWare it is libthread instead of libpthread. PHP and Apache have to be configured with EXTRA_LIBS=-lthread.

Příklad 1. OCI Hints

<?php // by sergo@bacup.ru // Use option: OCI_DEFAULT for execute command to delay execution OCIExecute($stmt, OCI_DEFAULT); // for retrieve data use (after fetch): $result = OCIResult($stmt, $n); if (is_object ($result)) $result = $result->load(); // For INSERT or UPDATE statement use: $sql = "insert into table (field1, field2) values (field1 = 'value', field2 = empty_clob()) returning field2 into :field2"; OCIParse($conn, $sql); $clob = OCINewDescriptor($conn, OCI_D_LOB); OCIBindByName ($stmt, ":field2", &$clob, -1, OCI_B_CLOB); OCIExecute($stmt, OCI_DEFAULT); $clob->save ("some text"); OCICommit($conn); ?>

You can easily access stored procedures in the same way as you would from the commands line.

Příklad 2. Using Stored Procedures

<?php // by webmaster@remoterealty.com $sth = OCIParse ( $dbh, "begin sp_newaddress( :address_id, '$firstname', '$lastname', '$company', '$address1', '$address2', '$city', '$state', '$postalcode', '$country', :error_code );end;" ); // This calls stored procedure sp_newaddress, with :address_id being an // in/out variable and :error_code being an out variable. // Then you do the binding: OCIBindByName ( $sth, ":address_id", $addr_id, 10 ); OCIBindByName ( $sth, ":error_code", $errorcode, 10 ); OCIExecute ( $sth ); ?>

Obsah
OCIBindByName -- Bind a PHP variable to an Oracle Placeholder
OCICancel -- Cancel reading from cursor
OCICollAppend -- Coming soon
OCICollAssign -- Coming soon
OCICollAssignElem -- Coming soon
OCICollGetElem -- Coming soon
OCICollMax -- Coming soon
OCICollSize -- Coming soon
OCICollTrim -- Coming soon
OCIColumnIsNULL -- Test whether a result column is NULL
OCIColumnName -- Returns the name of a column
OCIColumnPrecision -- Coming soon
OCIColumnScale -- Coming soon
OCIColumnSize -- Return result column size
OCIColumnType -- Returns the data type of a column
OCIColumnTypeRaw -- Coming soon
OCICommit -- Commits outstanding transactions
OCIDefineByName -- Use a PHP variable for the define-step during a SELECT
OCIError -- Return the last error of stmt|conn|global
OCIExecute -- Execute a statement
OCIFetch -- Fetches the next row into result-buffer
OCIFetchInto -- Fetches the next row into result-array
OCIFetchStatement -- Fetch all rows of result data into an array
OCIFreeCollection -- Coming soon
OCIFreeCursor -- Free all resources associated with a cursor
OCIFreeDesc -- Deletes a large object descriptor
OCIFreeStatement -- Free all resources associated with a statement
OCIInternalDebug -- Enables or disables internal debug output
OCILoadLob -- Coming soon
OCILogOff -- Disconnects from Oracle
OCILogon -- Establishes a connection to Oracle
OCINewCollection -- Coming soon
OCINewCursor -- Return a new cursor (Statement-Handle)
OCINewDescriptor -- Initialize a new empty LOB or FILE descriptor
OCINLogon -- Establishes a new connection to Oracle
OCINumCols -- Return the number of result columns in a statement
OCIParse -- Parse a query and return a statement
OCIPLogon -- Connect to an Oracle database using a persistent connection
OCIResult -- Returns column value for fetched row
OCIRollback -- Rolls back outstanding transactions
OCIRowCount -- Gets the number of affected rows
OCISaveLob -- Coming soon
OCISaveLobFile -- Coming soon
OCIServerVersion -- Return a string containing server version information
OCISetPrefetch -- Sets number of rows to be prefetched
OCIStatementType -- Return the type of an OCI statement
OCIWriteLobToFile -- Coming soon

OCIBindByName

(PHP 3>= 3.0.4, PHP 4 )

OCIBindByName -- Bind a PHP variable to an Oracle Placeholder

Description

int OCIBindByName ( int stmt, string ph_name, mixed & variable, int length [, int type])

OCIBindByName() binds the PHP variable variable to the Oracle placeholder ph_name. Whether it will be used for input or output will be determined run-time, and the necessary storage space will be allocated. The length parameter sets the maximum length for the bind. If you set length to -1 OCIBindByName() will use the current length of variable to set the maximum length.

If you need to bind an abstract Datatype (LOB/ROWID/BFILE) you need to allocate it first using OCINewDescriptor() function. The length is not used for abstract Datatypes and should be set to -1. The type variable tells oracle, what kind of descriptor we want to use. Possible values are: OCI_B_FILE (Binary-File), OCI_B_CFILE (Character-File), OCI_B_CLOB (Character-LOB), OCI_B_BLOB (Binary-LOB) and OCI_B_ROWID (ROWID).

Příklad 1. OCIDefineByName

<?php
/* OCIBindByPos example thies@thieso.net (980221)
  inserts 3 records into emp, and uses the ROWID for updating the 
  records just after the insert.
*/

$conn = OCILogon("scott","tiger");

$stmt = OCIParse($conn,"insert into emp (empno, ename) ".
					   "values (:empno,:ename) ".
					   "returning ROWID into :rid");

$data = array(1111 => "Larry", 2222 => "Bill", 3333 => "Jim");

$rowid = OCINewDescriptor($conn,OCI_D_ROWID);

OCIBindByName($stmt,":empno",&$empno,32);
OCIBindByName($stmt,":ename",&$ename,32);
OCIBindByName($stmt,":rid",&$rowid,-1,OCI_B_ROWID);

$update = OCIParse($conn,"update emp set sal = :sal where ROWID = :rid");
OCIBindByName($update,":rid",&$rowid,-1,OCI_B_ROWID);
OCIBindByName($update,":sal",&$sal,32);

$sal = 10000;

while (list($empno,$ename) = each($data)) {
	OCIExecute($stmt);
	OCIExecute($update);
} 

$rowid->free();

OCIFreeStatement($update);
OCIFreeStatement($stmt);

$stmt = OCIParse($conn,"select * from emp where empno in (1111,2222,3333)");
OCIExecute($stmt);
while (OCIFetchInto($stmt,&$arr,OCI_ASSOC)) {
	var_dump($arr);
}
OCIFreeStatement($stmt);

/* delete our "junk" from the emp table.... */
$stmt = OCIParse($conn,"delete from emp where empno in (1111,2222,3333)");
OCIExecute($stmt);
OCIFreeStatement($stmt);

OCILogoff($conn);
?>

Varování

It is a bad idea to use magic quotes and OciBindByName() simultaneously as no quoting is needed on quoted variables and any quotes magically applied will be written into your database as OciBindByName() is not able to distinguish magically added quotings from those added by intention.

OCICancel

(PHP 3>= 3.0.8, PHP 4 )

OCICancel -- Cancel reading from cursor

int OCIExecute ( int statement [, int mode])

OCIExecute() executes a previously parsed statement. (see OCIParse()). The optional mode allows you to specify the execution-mode (default is OCI_COMMIT_ON_SUCCESS). If you don't want statements to be committed automatically specify OCI_DEFAULT as your mode.

Vrací TRUE při úspěchu, FALSE při selhání.

OCIFetch

(PHP 3>= 3.0.4, PHP 4 )

OCIFetch -- Fetches the next row into result-buffer

Description

int OCIFetch ( int statement)

OCIFetch() fetches the next row (for SELECT statements) into the internal result-buffer.

OCIFetchInto

(PHP 3>= 3.0.4, PHP 4 )

OCIFetchInto -- Fetches the next row into result-array

Description

int OCIFetchInto ( int stmt, array & result [, int mode])

OCIFetchInto() fetches the next row (for SELECT statements) into the result array. OCIFetchInto() will overwrite the previous content of result. By default result will contain a zero-based array of all columns that are not NULL.

The mode parameter allows you to change the default behaviour. You can specify more than one flag by simply adding them up (eg OCI_ASSOC+OCI_RETURN_NULLS). The known flags are:

OCI_ASSOC Return an associative array.

OCI_NUM Return an numbered array starting with zero. (DEFAULT)

OCI_RETURN_NULLS Return empty columns.

OCI_RETURN_LOBS Return the value of a LOB instead of the descriptor.

OCIFetchStatement

(PHP 3>= 3.0.8, PHP 4 )

OCIFetchStatement -- Fetch all rows of result data into an array

Description

int OCIFetchStatement ( int stmt, array & variable)

OCIFetchStatement() fetches all the rows from a result into a user-defined array. OCIFetchStatement() returns the number of rows fetched.

Příklad 1. OCIFetchStatement

<?php
/* OCIFetchStatement example mbritton@verinet.com (990624) */

$conn = OCILogon("scott","tiger");

$stmt = OCIParse($conn,"select * from emp");

OCIExecute($stmt);

$nrows = OCIFetchStatement($stmt,$results);
if ( $nrows > 0 ) {
   print "<TABLE BORDER=\"1\">\n";
   print "<TR>\n";
   while ( list( $key, $val ) = each( $results ) ) {
      print "<TH>$key</TH>\n";
   }
   print "</TR>\n";
   
   for ( $i = 0; $i < $nrows; $i++ ) {
      reset($results);
      print "<TR>\n";
      while ( $column = each($results) ) {   
         $data = $column['value'];
         print "<TD>$data[$i]</TD>\n";
      }
      print "</TR>\n";
   }
   print "</TABLE>\n";
} else {
   echo "No data found<BR>\n";
}      
print "$nrows Records Selected<BR>\n";
 
OCIFreeStatement($stmt);
OCILogoff($conn);
?>

OCIFreeCollection

(PHP 4 >= 4.1.0)

OCIFreeCollection -- Coming soon

Description

string OCIFreeCollection ( object lob)

string OCILoadLob ( object lob)

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

OCILogOff

(PHP 3>= 3.0.4, PHP 4 )

OCILogOff -- Disconnects from Oracle

Description

int OCILogOff ( int connection)

OCILogOff() closes an Oracle connection.

OCILogon

(PHP 3>= 3.0.4, PHP 4 )

OCILogon -- Establishes a connection to Oracle

Description

int OCILogon ( string username, string password [, string db])

OCILogon() returns an connection identifier needed for most other OCI calls. The optional third parameter can either contain the name of the local Oracle instance or the name of the entry in tnsnames.ora to which you want to connect. If the optional third parameter is not specified, PHP uses the environment variables ORACLE_SID (Oracle instance) or TWO_TASK (tnsnames.ora) to determine which database to connect to.

Connections are shared at the page level when using OCILogon(). This means that commits and rollbacks apply to all open transactions in the page, even if you have created multiple connections.

This example demonstrates how the connections are shared.

Příklad 1. OCILogon

<?php print "<HTML><PRE>"; $db = ""; $c1 = ocilogon("scott","tiger",$db); $c2 = ocilogon("scott","tiger",$db); function create_table($conn) { $stmt = ociparse($conn,"create table scott.hallo (test varchar2(64))"); ociexecute($stmt); echo $conn." created table\n\n"; } function drop_table($conn) { $stmt = ociparse($conn,"drop table scott.hallo"); ociexecute($stmt); echo $conn." dropped table\n\n"; } function insert_data($conn) { $stmt = ociparse($conn,"insert into scott.hallo values('$conn' || ' ' || to_char(sysdate,'DD-MON-YY HH24:MI:SS'))"); ociexecute($stmt,OCI_DEFAULT); echo $conn." inserted hallo\n\n"; } function delete_data($conn) { $stmt = ociparse($conn,"delete from scott.hallo"); ociexecute($stmt,OCI_DEFAULT); echo $conn." deleted hallo\n\n"; } function commit($conn) { ocicommit($conn); echo $conn." committed\n\n"; } function rollback($conn) { ocirollback($conn); echo $conn." rollback\n\n"; } function select_data($conn) { $stmt = ociparse($conn,"select * from scott.hallo"); ociexecute($stmt,OCI_DEFAULT); echo $conn."----selecting\n\n"; while (ocifetch($stmt)) echo $conn." <".ociresult($stmt,"TEST").">\n\n"; echo $conn."----done\n\n"; } create_table($c1); insert_data($c1); // Insert a row using c1 insert_data($c2); // Insert a row using c2 select_data($c1); // Results of both inserts are returned select_data($c2); rollback($c1); // Rollback using c1 select_data($c1); // Both inserts have been rolled back select_data($c2); insert_data($c2); // Insert a row using c2 commit($c2); // commit using c2 select_data($c1); // result of c2 insert is returned delete_data($c1); // delete all rows in table using c1 select_data($c1); // no rows returned select_data($c2); // no rows returned commit($c1); // commit using c1 select_data($c1); // no rows returned select_data($c2); // no rows returned drop_table($c1); print "</PRE></HTML>"; ?>

See also OCIPLogon() and OCINLogon().

OCINewCollection

(PHP 4 >= 4.0.6)

OCINewCollection -- Coming soon

Description

string OCINewCollection ( int conn, string tdo [, string shema])

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

OCINewCursor

(PHP 3>= 3.0.8, PHP 4 )

OCINewCursor -- Return a new cursor (Statement-Handle)

Description

int OCINewCursor ( int conn)

OCINewCursor() allocates a new statement handle on the specified connection.

Příklad 1. Using a REF CURSOR from a stored procedure

<?php // suppose your stored procedure info.output returns a ref cursor in :data $conn = OCILogon("scott","tiger"); $curs = OCINewCursor($conn); $stmt = OCIParse($conn,"begin info.output(:data); end;"); ocibindbyname($stmt,"data",&$curs,-1,OCI_B_CURSOR); ociexecute($stmt); ociexecute($curs); while (OCIFetchInto($curs,&$data)) { var_dump($data); } OCIFreeStatement($stmt); OCIFreeCursor($curs); OCILogoff($conn); ?>

Příklad 2. Using a REF CURSOR in a select statement

<?php print "<HTML><BODY>"; $conn = OCILogon("scott","tiger"); $count_cursor = "CURSOR(select count(empno) num_emps from emp " . "where emp.deptno = dept.deptno) as EMPCNT from dept"; $stmt = OCIParse($conn,"select deptno,dname,$count_cursor"); ociexecute($stmt); print "<TABLE BORDER=\"1\">"; print "<TR>"; print "<TH>DEPT NAME</TH>"; print "<TH>DEPT #</TH>"; print "<TH># EMPLOYEES</TH>"; print "</TR>"; while (OCIFetchInto($stmt,&$data,OCI_ASSOC)) { print "<TR>"; $dname = $data["DNAME"]; $deptno = $data["DEPTNO"]; print "<TD>$dname</TD>"; print "<TD>$deptno</TD>"; ociexecute($data["EMPCNT"]); while (OCIFetchInto($data["EMPCNT"],&$subdata,OCI_ASSOC)) { $num_emps = $subdata["NUM_EMPS"]; print "<TD>$num_emps</TD>"; } print "</TR>"; } print "</TABLE>"; print "</BODY></HTML>"; OCIFreeStatement($stmt); OCILogoff($conn); ?>

OCINewDescriptor

(PHP 3>= 3.0.7, PHP 4 )

OCINewDescriptor -- Initialize a new empty LOB or FILE descriptor

Description

string OCINewDescriptor ( int connection [, int type])

OCINewDescriptor() allocates storage to hold descriptors or LOB locators. Valid values for type are OCI_D_FILE, OCI_D_LOB, OCI_D_ROWID. For LOB descriptors, the methods load, save, and savefile are associated with the descriptor, for BFILE only the load method exists. See the second example usage hints.

Příklad 1. OCINewDescriptor

<?php   
    /* This script is designed to be called from a HTML form.
     * It expects $user, $password, $table, $where, and $commitsize
     * to be passed in from the form.  The script then deletes
     * the selected rows using the ROWID and commits after each
     * set of $commitsize rows. (Use with care, there is no rollback)
     */
    $conn = OCILogon($user, $password);
    $stmt = OCIParse($conn,"select rowid from $table $where");
    $rowid = OCINewDescriptor($conn,OCI_D_ROWID);
    OCIDefineByName($stmt,"ROWID",&$rowid);   
    OCIExecute($stmt);
    while ( OCIFetch($stmt) ) {      
       $nrows = OCIRowCount($stmt);
       $delete = OCIParse($conn,"delete from $table where ROWID = :rid");
       OCIBindByName($delete,":rid",&$rowid,-1,OCI_B_ROWID);
       OCIExecute($delete);      
       print "$nrows\n";
       if ( ($nrows % $commitsize) == 0 ) {
           OCICommit($conn);      
       }   
    }
    $nrows = OCIRowCount($stmt);   
    print "$nrows deleted...\n";
    OCIFreeStatement($stmt);  
    OCILogoff($conn);
?>

<?php
    /* This script demonstrates file upload to LOB columns
     * The formfield used for this example looks like this
     * <form action="upload.php" method="post" enctype="multipart/form-data">
     * <input type="file" name="lob_upload">
     * ...
     */
  if(!isset($lob_upload) || $lob_upload == 'none'){
?>
<form action="upload.php" method="post" enctype="multipart/form-data">
Upload file: <input type="file" name="lob_upload"><br>
<input type="submit" value="Upload"> - <input type="reset">
</form>
<?php
  } else {

     // $lob_upload contains the temporary filename of the uploaded file

     // see also the features section on file upload,
     // if you would like to use secure uploads
     
     $conn = OCILogon($user, $password);
     $lob = OCINewDescriptor($conn, OCI_D_LOB);
     $stmt = OCIParse($conn,"insert into $table (id, the_blob) 
               values(my_seq.NEXTVAL, EMPTY_BLOB()) returning the_blob into :the_blob");
     OCIBindByName($stmt, ':the_blob', &$lob, -1, OCI_B_BLOB);
     OCIExecute($stmt, OCI_DEFAULT);
     if($lob->savefile($lob_upload)){
        OCICommit($conn);
        echo "Blob successfully uploaded\n";
     }else{
        echo "Couldn't upload Blob\n";
     }
     OCIFreeDesc($lob);
     OCIFreeStatement($stmt);
     OCILogoff($conn);
  }
?>

Příklad 2. OCINewDescriptor

<?php   
    /* Calling PL/SQL stored procedures which contain clobs as input
     * parameters (PHP 4 >= 4.0.6). 
     * Example PL/SQL stored procedure signature is:
     *
     * PROCEDURE save_data
     *   Argument Name                  Type                    In/Out Default?
     *   ------------------------------ ----------------------- ------ --------
     *   KEY                            NUMBER(38)              IN
     *   DATA                           CLOB                    IN
     *
     */

    $conn = OCILogon($user, $password);
    $stmt = OCIParse($conn, "begin save_data(:key, :data); end;");
    $clob = OCINewDescriptor($conn, OCI_D_LOB);
	OCIBindByName($stmt, ':key', $key);
	OCIBindByName($stmt, ':data', $clob, -1, OCI_B_CLOB);
	$clob->WriteTemporary($data);
	OCIExecute($stmt, OCI_DEFAULT);
	OCICommit($conn);
	$clob->close();
	$clob->free();
	OCIFreeStatement($stmt);
?>

OCINLogon

(PHP 3>= 3.0.8, PHP 4 )

OCINLogon -- Establishes a new connection to Oracle

Description

int OCINLogon ( string username, string password [, string db])

OCINLogon() creates a new connection to an Oracle 8 database and logs on. The optional third parameter can either contain the name of the local Oracle instance or the name of the entry in tnsnames.ora to which you want to connect. If the optional third parameter is not specified, PHP uses the environment variables ORACLE_SID (Oracle instance) or TWO_TASK (tnsnames.ora) to determine which database to connect to.

OCINLogon() forces a new connection. This should be used if you need to isolate a set of transactions. By default, connections are shared at the page level if using OCILogon() or at the web server process level if using OCIPLogon(). If you have multiple connections open using OCINLogon(), all commits and rollbacks apply to the specified connection only.

This example demonstrates how the connections are separated.

Příklad 1. OCINLogon

<?php print "<HTML><PRE>"; $db = ""; $c1 = ocilogon("scott","tiger",$db); $c2 = ocinlogon("scott","tiger",$db); function create_table($conn) { $stmt = ociparse($conn,"create table scott.hallo (test varchar2(64))"); ociexecute($stmt); echo $conn." created table\n\n"; } function drop_table($conn) { $stmt = ociparse($conn,"drop table scott.hallo"); ociexecute($stmt); echo $conn." dropped table\n\n"; } function insert_data($conn) { $stmt = ociparse($conn,"insert into scott.hallo values('$conn' || ' ' || to_char(sysdate,'DD-MON-YY HH24:MI:SS'))"); ociexecute($stmt,OCI_DEFAULT); echo $conn." inserted hallo\n\n"; } function delete_data($conn) { $stmt = ociparse($conn,"delete from scott.hallo"); ociexecute($stmt,OCI_DEFAULT); echo $conn." deleted hallo\n\n"; } function commit($conn) { ocicommit($conn); echo $conn." committed\n\n"; } function rollback($conn) { ocirollback($conn); echo $conn." rollback\n\n"; } function select_data($conn) { $stmt = ociparse($conn,"select * from scott.hallo"); ociexecute($stmt,OCI_DEFAULT); echo $conn."----selecting\n\n"; while (ocifetch($stmt)) echo $conn." <".ociresult($stmt,"TEST").">\n\n"; echo $conn."----done\n\n"; } create_table($c1); insert_data($c1); select_data($c1); select_data($c2); rollback($c1); select_data($c1); select_data($c2); insert_data($c2); commit($c2); select_data($c1); delete_data($c1); select_data($c1); select_data($c2); commit($c1); select_data($c1); select_data($c2); drop_table($c1); print "</PRE></HTML>"; ?>

See also OCILogon() and OCIPLogon().

OCINumCols

(PHP 3>= 3.0.4, PHP 4 )

OCINumCols -- Return the number of result columns in a statement

Description

int OCINumCols ( int stmt)

OCINumCols() returns the number of columns in a statement.

Příklad 1. OCINumCols

<?php   
    print "<HTML><PRE>\n";   
    $conn = OCILogon("scott", "tiger");
    $stmt = OCIParse($conn,"select * from emp");
    OCIExecute($stmt);
    while ( OCIFetch($stmt) ) {
        print "\n";   
        $ncols = OCINumCols($stmt);
        for ( $i = 1; $i <= $ncols; $i++ ) {
            $column_name  = OCIColumnName($stmt,$i);
            $column_value = OCIResult($stmt,$i);
            print $column_name . ': ' . $column_value . "\n";
        }
        print "\n";
    }
    OCIFreeStatement($stmt);  
    OCILogoff($conn);   
    print "</PRE>";
    print "</HTML>\n"; 
?>

OCIParse

(PHP 3>= 3.0.4, PHP 4 )

OCIParse -- Parse a query and return a statement

Description

int OCIParse ( int conn, string query)

OCIParse() parses the query using conn. It returns the statement identity if the query is valid, FALSE if not. The query can be any valid SQL statement or PL/SQL block.

OCIPLogon

(PHP 3>= 3.0.8, PHP 4 )

OCIPLogon -- Connect to an Oracle database using a persistent connection

Description

int OCIPLogon ( string username, string password [, string db])

string OCIStatementType ( int stmt)

OCIStatementType() returns one of the following values:

"SELECT"
"UPDATE"
"DELETE"
"INSERT"
"CREATE"
"DROP"
"ALTER"
"BEGIN"
"DECLARE"
"UNKNOWN"

Příklad 1. OCIStatementType() examples

<?php print "<HTML><PRE>"; $conn = OCILogon("scott","tiger"); $sql = "delete from emp where deptno = 10"; $stmt = OCIParse($conn,$sql); if ( OCIStatementType($stmt) == "DELETE" ) { die "You are not allowed to delete from this table<BR>"; } OCILogoff($conn); print "</PRE></HTML>"; ?>

OCIWriteLobToFile

(PHP 4 )

OCIWriteLobToFile -- Coming soon

Description

void OCIWriteLobToFile ( object lob [, string filename [, int start [, int lenght]]])

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

LXXI. OpenSSL funkce

Varování

Tato extenze využívá funkce OpenSSL pro tvorbu a ověřování podpisů a pečetění (kódování) a otvírání (dekódování) dat. K práci s touto extenzí potřebujete OpenSSL >= 0.9.6.

OpenSSL nabízí mnoho vlastností, které tato extenze v současnosti nepodporuje. Některé z nich mohou být v budoucnu přidány.

Obsah
openssl_csr_export_to_file -- Exports a CSR to file or a var
openssl_csr_export -- Exports a CSR to file or a var
openssl_csr_new -- Generates a privkey and CSR
openssl_csr_sign -- Signs a cert with another CERT
openssl_error_string -- Return openSSL error message
openssl_free_key -- Uvolnit prostředky klíče
openssl_get_privatekey -- Připravit soukromý PEM klíč k použití
openssl_get_publickey -- Získat z certifikátu veřejný klíč a připravit ho k použití
openssl_open -- Otevřít zapečetěná data
openssl_pkcs7_decrypt -- Decrypts an S/MIME encrypted message
openssl_pkcs7_encrypt -- Encrypt an S/MIME message
openssl_pkcs7_sign -- sign an S/MIME message
openssl_pkcs7_verify -- Verifies the signature of an S/MIME signed message
openssl_pkey_export_to_file -- Gets an exportable representation of a key into a file
openssl_pkey_export -- Gets an exportable representation of a key into a string or file
openssl_pkey_new -- Generates a new private key
openssl_private_decrypt -- Decrypts data with private key
openssl_private_encrypt -- Encrypts data with private key
openssl_public_decrypt -- Decrypts data with public key
openssl_public_encrypt -- Encrypts data with public key
openssl_seal -- Zapečetit (zakódovat) data
openssl_sign -- Generate signature
openssl_verify -- Ověřit podpis
openssl_x509_check_private_key -- Checks if a private key corresponds to a CERT
openssl_x509_checkpurpose -- Verifies if a certificate can be used for a particular purpose
openssl_x509_export_to_file -- Exports a CERT to file or a var
openssl_x509_export -- Exports a CERT to file or a var
openssl_x509_free -- Free certificate resource
openssl_x509_parse -- Parse an X509 certificate and return the information as an array
openssl_x509_read -- Parse an X.509 certificate and return a resource identifier for it

openssl_error_string() returns the last error from the openSSL library. Error messages are stacked, so this function should be called multiple times to collect all of the information.

The parameters/return type of this function may change before it appears in a release version of PHP

Příklad 1. openssl_error_string() example

// lets assume you just called an openssl function that failed while($msg = openssl_error_string()) echo $msg . "<br />\n";

Poznámka: This function was added in 4.0.6.

openssl_free_key

(PHP 4 >= 4.0.4)

openssl_free_key -- Uvolnit prostředky klíče

bool openssl_open ( string sealed_data, string open_data, string env_key, int priv_key_id)

Při úspěchu vrací TRUE, při chybě FALSE. Úspěšně otevřená data se umístí do argumentu open_data.

openssl_open() otevře (dekóduje) sealed_data pomocí soukromého klíče asociovaného s identifikátorem priv_key_id a obálkou env_key. Tato obálka se generuje při pečetění dat a je použitelná pouze s jedním utčitým soukromým klíčem. Více informací viz openssl_seal().

Příklad 1. Ukázka openssl_open()

// $sealed a $env_key obsahují zapečetěná data a obálku // obojí nám bylo dáno tím, kdo data zapečetil // získat ze souboru soukromý klíč a připravit ho $fp = fopen("/src/openssl-0.9.6/demos/sign/key.pem", "r"); $priv_key = fread($fp, 8192); fclose($fp); $pkeyid = openssl_get_privatekey($priv_key); // dekódovat data a uložit je v $open if (openssl_open($sealed, $open, $env_key, $pkeyid)) echo "tady jsou otevřená data: ", $open; else echo "nepodařilo se otevřít data"; // uvolnit klíč z paměti openssl_free_key($pkeyid);

Viz také openssl_seal().

openssl_pkcs7_decrypt

(PHP 4 >= 4.0.6)

openssl_pkcs7_decrypt -- Decrypts an S/MIME encrypted message

Description

bool openssl_pkcs7_decrypt ( string infilename, string outfilename, mixed recipcert, mixed recipkey)

Varování

Decrypts the S/MIME encrypted message contained in the file specified by infilename using the certificate and it's associated private key specified by recipcert and recipkey.

The decrypted message is output to the file specified by outfilename

Příklad 1. openssl_pkcs7_decrypt() example

// $cert and $key are assumed to contain your personal certificate and private // key pair, and that you are the recipient of an S/MIME message $infilename = "encrypted.msg"; // this file holds your encrypted message $outfilename = "decrypted.msg"; // make sure you can write to this file if (openssl_pkcs7_decrypt($infilename, $outfilename, $cert, $key)) echo "decrypted!"; else echo "failed to decrypt!";

Poznámka: This function was added in 4.0.6.

openssl_pkcs7_encrypt

(PHP 4 >= 4.0.6)

openssl_pkcs7_encrypt -- Encrypt an S/MIME message

Description

bool openssl_pkcs7_encrypt ( string infile, string outfile, mixed recipcerts, array headers [, long flags])

Varování

openssl_pkcs7_encrypt() takes the contents of the file named infile and encrypts them using an RC2 40-bit cipher so that they can only be read by the intended recipients specified by recipcerts, which is either a lone X.509 certificate, or an array of X.509 certificates. headers is an array of headers that will be prepended to the data after it has been encrypted. flags can be used to specify options that affect the encoding process - see PKCS7 constants. headers can be either an associative array keyed by header name, or an indexed array, where each element contains a single header line.

Příklad 1. openssl_pkcs7_encrypt() example

// the message you want to encrypt and send to your secret agent // in the field, known as nighthawk. You have his certificate // in the file nighthawk.pem $data = <<<EOD Nighthawk, Top secret, for your eyes only! The enemy is closing in! Meet me at the cafe at 8.30am to collect your forged passport! HQ EOD; // load key $key = implode("", file("nighthawk.pem")); // save message to file $fp = fopen("msg.txt", "w"); fwrite($fp, $data); fclose($fp); // encrypt it if (openssl_pkcs7_encrypt("msg.txt", "enc.txt", $key, array("To" => "nighthawk@example.com", // keyed syntax "From: HQ <hq@example.com>", // indexed syntax "Subject" => "Eyes only"))) { // message encrypted - send it! exec(ini_get("sendmail_path") . " < enc.txt"); }

openssl_pkcs7_sign

(PHP 4 >= 4.0.6)

openssl_pkcs7_sign -- sign an S/MIME message

Description

bool openssl_pkcs7_sign ( string infilename, string outfilename, mixed signcert, mixed privkey, array headers [, long flags [, string extracertsfilename]])

Varování

openssl_pkcs7_sign() takes the contents of the file named infilename and signs them using the certificate and it's matching private key specified by signcert and privkey parameters.

headers is an array of headers that will be prepended to the data after it has been signed (see openssl_pkcs7_encrypt() for more information about the format of this parameter.

flags can be used to alter the output - see PKCS7 constants - if not specified, it defaults to PKCS7_DETACHED.

extracerts specifies the name of a file containing a bunch of extra certificates to include in the signature which can for example be used to help the recipient to verify the certificate that you used.

Příklad 1. openssl_pkcs7_sign() example

// the message you want to sign so that recipient can be sure it was you that // sent it $data = <<<EOD You have my authorization to spend $10,000 on dinner expenses. The CEO EOD; // save message to file $fp = fopen("msg.txt", "w"); fwrite($fp, $data); fclose($fp); // encrypt it if (openssl_pkcs7_sign("msg.txt", "signed.txt", "mycert.pem", array("mycert.pem", "mypassphrase"), array("To" => "joes@sales.com", // keyed syntax "From: HQ <ceo@sales.com>", // indexed syntax "Subject" => "Eyes only")) { // message signed - send it! exec(ini_get("sendmail_path") . " < signed.txt"); }

Poznámka: This function was added in 4.0.6.

openssl_pkcs7_verify

(PHP 4 >= 4.0.6)

openssl_pkcs7_verify -- Verifies the signature of an S/MIME signed message

Description

bool openssl_pkcs7_verify ( string filename, int flags [, string outfilename [, array cainfo [, string extracerts]]])

Varování

openssl_pkcs7_verify() reads the S/MIME message contained in the filename specified by filename and examines the digital signature. It returns TRUE if the signature is verified, FALSE if it is not correct (the message has been tampered with, or the signing certificate is invalid), or -1 on error.

flags can be used to affect how the signature is verified - see PKCS7 constants for more information.

If the outfilename is specified, it should be a string holding the name of a file into which the certificates of the persons that signed the messages will be stored in PEM format.

If the cainfo is specified, it should hold information about the trusted CA certificates to use in the verification process - see certificate verification for more information about this parameter.

If the extracerts is specified, it is the filename of a file containing a bunch of certificates to use as untrusted CAs.

Poznámka: This function was added in 4.0.6.

Příklad 1. Ukázka openssl_seal()

// $data obsahuje data určená k zapečetění // získat veřejné klíče našich příjemců a připravit je $fp = fopen("/src/openssl-0.9.6/demos/maurice/cert.pem", "r"); $cert = fread($fp, 8192); fclose($fp); $pk1 = openssl_get_publickey($cert); // opakovat prodruhého příjemce $fp = fopen("/src/openssl-0.9.6/demos/sign/cert.pem", "r"); $cert = fread($fp, 8192); fclose($fp); $pk2 = openssl_get_publickey($cert); // zapečetit zprávu, pouze majitelé $pk1 a $pk2 mohou dekódovat $sealed pomocí // $ekeys[0] a $ekeys[1]. openssl_seal($data, $sealed, $ekeys, array($pk1,$pk2)); // uvolnit klíče z paměti openssl_free_key($pk1); openssl_free_key($pk2);

Viz také openssl_open().

openssl_sign

(PHP 4 >= 4.0.4)

openssl_sign -- Generate signature

Popis

bool openssl_sign ( string data, string signature, int priv_key_id)

Při úspěchu vrací TRUE, při chybě FALSE. Úspěšně vytvořený podpis se umístí v signature.

openssl_sign() vypočítá podpis pro daná specified data pomocí SHA1 hashe a následně jej zakóduje soukromým klíčem asociovaným s priv_key_id. Pozn.: samotná data nejsou kódována.

Příklad 1. openssl_sign() example

// $data obsahuje data určená k podpisu // získat ze souboru soukromý klíč a připravit ho $fp = fopen("/src/openssl-0.9.6/demos/sign/key.pem", "r"); $priv_key = fread($fp, 8192); fclose($fp); $pkeyid = openssl_get_privatekey($priv_key); // vytvořit podpis openssl_sign($data, $signature, $pkeyid); // uvolnit klíč z paměti openssl_free_key($pkeyid);

Viz také openssl_verify().

openssl_verify

(PHP 4 >= 4.0.4)

openssl_verify -- Ověřit podpis

Popis

int openssl_verify ( string data, string signature, int pub_key_id)

Vrací 1, pokud je podpis správný, 0, pokud je nesprávný, a -1 při chybě.

openssl_verify() ověřuje, zda je signature správný pro data pomocí veřejného klíče asociovaného s pub_key_id. Musí to být veřejný klíč odpovídající soukromému klíči použitému k podpisu.

Příklad 1. Ukázka openssl_verify()

// $data a $signature obsahují data a podpis // získat z certifikátu veřejný klíč a připravit ho $fp = fopen("/src/openssl-0.9.6/demos/sign/cert.pem", "r"); $cert = fread($fp, 8192); fclose($fp); $pubkeyid = openssl_get_publickey($cert); // zjistit, jestli je podpis v pořádku $ok = openssl_verify($data, $signature, $pubkeyid); if ($ok == 1) echo "dobře"; elseif ($ok == 0) echo "špatně"; else echo "nejhůř, při kontrole podpisu došlo k chybě"; // uvolnit klíč z paměti openssl_free_key($pubkeyid);

Viz také openssl_sign().

openssl_x509_check_private_key

(PHP 4 >= 4.2.0)

openssl_x509_check_private_key -- Checks if a private key corresponds to a CERT

Description

bool openssl_x509_check_private_key ( mixed cert, mixed key)

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

openssl_x509_checkpurpose

(PHP 4 >= 4.0.6)

openssl_x509_checkpurpose -- Verifies if a certificate can be used for a particular purpose

Description

bool openssl_x509_checkpurpose ( mixed x509cert, int purpose, array cainfo [, string untrustedfile])

Varování

Returns TRUE if the certificate can be used for the intended purpose, FALSE if it cannot, or -1 on error.

openssl_x509_checkpurpose() examines the certificate specified by x509cert to see if it can be used for the purpose specified by purpose.

cainfo should be an array of trusted CA files/dirs as described in Certificate Verification.

untrustedfile, if specified, is the name of a PEM encoded file holding certificates that can be used to help verify the certificate, although no trust in placed in the certificates that come from that file.

Tabulka 1. openssl_x509_checkpurpose() purposes

Constant	Description
X509_PURPOSE_SSL_CLIENT	Can the certificate be used for the client side of an SSL connection?
X509_PURPOSE_SSL_SERVER	Can the certificate be used for the server side of an SSL connection?
X509_PURPOSE_NS_SSL_SERVER	Can the cert be used for Netscape SSL server?
X509_PURPOSE_SMIME_SIGN	Can the cert be used to sign S/MIME email?
X509_PURPOSE_SMIME_ENCRYPT	Can the cert be used to encrypt S/MIME email?
X509_PURPOSE_CRL_SIGN	Can the cert be used to sign a certificate revocation list (CRL)?
X509_PURPOSE_ANY	Can the cert be used for Any/All purposes?

These options are not bitfields - you may specify one only!

Poznámka: This function was added in 4.0.6.

Poznámka: This function was added in 4.0.6.

openssl_x509_parse

(PHP 4 >= 4.0.6)

openssl_x509_parse -- Parse an X509 certificate and return the information as an array

Description

array openssl_x509_parse ( mixed x509cert [, bool shortnames])

Varování

openssl_x509_parse() returns information about the supplied x509cert, including fields such as subject name, issuer name, purposes, valid from and valid to dates etc. shortnames controls how the data is indexed in the array - if shortnames is TRUE (the default) then fields will be indexed with the short name form, otherwise, the long name form will be used - e.g.: CN is the shortname form of commonName.

The structure of the returned data is (deliberately) not yet documented, as it is still subject to change.

Poznámka: This function was added in 4.0.6.

openssl_x509_read

(PHP 4 >= 4.0.6)

openssl_x509_read -- Parse an X.509 certificate and return a resource identifier for it

Description

resource openssl_x509_read ( mixed x509certdata)

Varování

openssl_x509_read() parses the certificate supplied by x509certdata and returns a resource identifier for it.

Poznámka: This function was added in 4.0.6.

LXXII. Oracle functions

Obsah
Ora_Bind -- bind a PHP variable to an Oracle parameter
Ora_Close -- close an Oracle cursor
Ora_ColumnName -- get name of Oracle result column
Ora_ColumnSize -- get size of Oracle result column
Ora_ColumnType -- get type of Oracle result column
Ora_Commit -- commit an Oracle transaction
Ora_CommitOff -- disable automatic commit
Ora_CommitOn -- enable automatic commit
Ora_Do -- Parse, Exec, Fetch
Ora_Error -- get Oracle error message
Ora_ErrorCode -- get Oracle error code
Ora_Exec -- execute parsed statement on an Oracle cursor
Ora_Fetch_Into -- Fetch a row into the specified result array
Ora_Fetch -- fetch a row of data from a cursor
Ora_GetColumn -- get data from a fetched column
Ora_Logoff -- close an Oracle connection
Ora_Logon -- open an Oracle connection
Ora_Numcols -- Returns the number of columns
Ora_Numrows -- Returns the number of rows
Ora_Open -- open an Oracle cursor
Ora_Parse -- parse an SQL statement
Ora_pLogon -- Open a persistent Oracle connection
Ora_Rollback -- roll back transaction

Ora_Bind

(PHP 3, PHP 4 )

Ora_Bind -- bind a PHP variable to an Oracle parameter

Description

int ora_bind ( int cursor, string PHP variable name, string SQL parameter name, int length [, int type])

Returns TRUE if the bind succeeds, otherwise FALSE. Details about the error can be retrieved using the ora_error() and ora_errorcode() functions.

This function binds the named PHP variable with a SQL parameter. The SQL parameter must be in the form ":name". With the optional type parameter, you can define whether the SQL parameter is an in/out (0, default), in (1) or out (2) parameter. As of PHP 3.0.1, you can use the constants ORA_BIND_INOUT, ORA_BIND_IN and ORA_BIND_OUT instead of the numbers.

ora_bind must be called after ora_parse() and before ora_exec(). Input values can be given by assignment to the bound PHP variables, after calling ora_exec() the bound PHP variables contain the output values if available.

<?php
ora_parse($curs, "declare tmp INTEGER; begin tmp := :in; :out := tmp; :x := 7.77; end;");
ora_bind($curs, "result", ":x", $len, 2);
ora_bind($curs, "input", ":in", 5, 1);
ora_bind($curs, "output", ":out", 5, 2);
$input = 765;
ora_exec($curs);
echo "Result: $result<BR>Out: $output<BR>In: $input";
?>

Ora_Close

(PHP 3, PHP 4 )

Ora_Close -- close an Oracle cursor

Description

int ora_close ( int cursor)

string Ora_ColumnType ( int cursor, int column)

Returns the Oracle data type name of the field/column column on the cursor cursor. Column 0 is the first column. The returned type will be one of the following:

"VARCHAR2"

"VARCHAR"

"CHAR"

"NUMBER"

"LONG"

"LONG RAW"

string Ora_Error ( int cursor_or_connection)

Returns an error message of the form XXX-NNNNN where XXX is where the error comes from and NNNNN identifies the error message.

Poznámka: Support for connection ids was added in 3.0.4.

On UNIX versions of Oracle, you can find details about an error message like this: $ oerr ora 00001 00001, 00000, "unique constraint (%s.%s) violated" // *Cause: An update or insert statement attempted to insert a duplicate key // For Trusted ORACLE configured in DBMS MAC mode, you may see // this message if a duplicate entry exists at a different level. // *Action: Either remove the unique restriction or do not insert the key

Ora_ErrorCode

(PHP 3, PHP 4 )

Ora_ErrorCode -- get Oracle error code

Description

int Ora_ErrorCode ( int cursor_or_connection)

Returns the numeric error code of the last executed statement on the specified cursor or connection.

Poznámka: Support for connection ids was added in 3.0.4.

Ora_Exec

(PHP 3, PHP 4 )

Ora_Exec -- execute parsed statement on an Oracle cursor

Description

int ora_exec ( int cursor)

Returns TRUE on success, FALSE on error. Details about the error can be retrieved using the ora_error() and ora_errorcode() functions.

Ora_Fetch_Into

(PHP 3, PHP 4 )

Ora_Fetch_Into -- Fetch a row into the specified result array

Description

int ora_fetch_into ( int cursor, array result [, int flags])

Ora_Parse

(PHP 3, PHP 4 )

Ora_Parse -- parse an SQL statement

Description

int ora_parse ( int cursor_ind, string sql_statement, int defer)

This function parses an SQL statement or a PL/SQL block and associates it with the given cursor.

Vrací TRUE při úspěchu, FALSE při selhání.

See also ora_exec(), ora_fetch(), and ora_do().

Ora_pLogon

(PHP 3, PHP 4 )

Ora_pLogon -- Open a persistent Oracle connection

Description

int ora_plogon ( string user, string password)

Establishes a persistent connection between PHP and an Oracle database with the given username and password.

Ora_Rollback

(PHP 3, PHP 4 )

Ora_Rollback -- roll back transaction

Description

int ora_rollback ( int connection)

This function undoes an Oracle transaction. (See ora_commit() for the definition of a transaction.)

Returns TRUE on success, FALSE on error. Details about the error can be retrieved using the ora_error() and ora_errorcode() functions.

LXXIII. Ovrimos SQL functions

Ovrimos SQL Server, is a client/server, transactional RDBMS combined with Web capabilities and fast transactions.

Ovrimos SQL Server is available at http://www.ovrimos.com/. To enable ovrimos support in PHP just compile PHP with the --with-ovrimos parameter to configure script. You'll need to install the sqlcli library available in the Ovrimos SQL Server distribution.

Příklad 1. Connect to Ovrimos SQL Server and select from a system table

<?php $conn = ovrimos_connect ("server.domain.com", "8001", "admin", "password"); if ($conn != 0) { echo ("Connection ok!"); $res = ovrimos_exec ($conn, "select table_id, table_name from sys.tables"); if ($res != 0) { echo "Statement ok!"; ovrimos_result_all ($res); ovrimos_free_result ($res); } ovrimos_close($conn); } ?>
This will just connect to an Ovrimos SQL server.

Obsah
ovrimos_close -- Closes the connection to ovrimos
ovrimos_commit -- Commits the transaction
ovrimos_connect -- Connect to the specified database
ovrimos_cursor -- Returns the name of the cursor
ovrimos_exec -- Executes an SQL statement
ovrimos_execute -- Executes a prepared SQL statement
ovrimos_fetch_into -- Fetches a row from the result set
ovrimos_fetch_row -- Fetches a row from the result set
ovrimos_field_len -- Returns the length of the output column
ovrimos_field_name -- Returns the output column name
ovrimos_field_num -- Returns the (1-based) index of the output column
ovrimos_field_type -- Returns the (numeric) type of the output column
ovrimos_free_result -- Frees the specified result_id
ovrimos_longreadlen -- Specifies how many bytes are to be retrieved from long datatypes
ovrimos_num_fields -- Returns the number of columns
ovrimos_num_rows -- Returns the number of rows affected by update operations
ovrimos_prepare -- Prepares an SQL statement
ovrimos_result_all -- Prints the whole result set as an HTML table
ovrimos_result -- Retrieves the output column
ovrimos_rollback -- Rolls back the transaction

ovrimos_fetch_into() fetches a row from the result set into 'result_array', which should be passed by reference. Which row is fetched is determined by the two last parameters. 'how' is one of 'Next' (default), 'Prev', 'First', 'Last', 'Absolute', corresponding to forward direction from current position, backward direction from current position, forward direction from the start, backward direction from the end and absolute position from the start (essentially equivalent to 'first' but needs 'rownumber'). Case is not significant. 'Rownumber' is optional except for absolute positioning. Returns TRUE or FALSE.

Příklad 1. A fetch into example

<?php $conn=ovrimos_connect ("neptune", "8001", "admin", "password"); if ($conn!=0) { echo "Connection ok!"; $res=ovrimos_exec ($conn,"select table_id, table_name from sys.tables"); if ($res != 0) { echo "Statement ok!"; if (ovrimos_fetch_into ($res, &$row)) { list ($table_id, $table_name) = $row; echo "table_id=".$table_id.", table_name=".$table_name."\n"; if (ovrimos_fetch_into ($res, &$row)) { list ($table_id, $table_name) = $row; echo "table_id=".$table_id.", table_name=".$table_name."\n"; } else { echo "Next: error\n"; } } else { echo "First: error\n"; } ovrimos_free_result ($res); } ovrimos_close($conn); } ?>
This example will fetch a row.

ovrimos_fetch_row

(PHP 4 >= 4.0.3)

ovrimos_fetch_row -- Fetches a row from the result set

Description

bool ovrimos_fetch_row ( int result_id [, int how [, int row_number]])

int ovrimos_prepare ( int connection_id, string query)

ovrimos_prepare() is used to prepare an SQL statement.

ovrimos_prepare() prepares an SQL statement and returns a result_id (or FALSE on failure).

Příklad 1. Connect to Ovrimos SQL Server and prepare a statement

<?php $conn=ovrimos_connect ("db_host", "8001", "admin", "password"); if ($conn!=0) { echo "Connection ok!"; $res=ovrimos_prepare ($conn, "select table_id, table_name from sys.tables where table_id=1"); if ($res != 0) { echo "Prepare ok!"; if (ovrimos_execute ($res)) { echo "Execute ok!\n"; ovrimos_result_all ($res); } else { echo "Execute not ok!"; } ovrimos_free_result ($res); } else { echo "Prepare not ok!\n"; } ovrimos_close($conn); } ?>
This will connect to Ovrimos SQL Server, prepare a statement and the execute it.

ovrimos_result_all

(PHP 4 >= 4.0.3)

ovrimos_result_all -- Prints the whole result set as an HTML table

Description

bool ovrimos_result_all ( int result_id [, string format])

ovrimos_result_all() is used to print an HTML table containing the whole result set.

ovrimos_result_all() prints the whole result set as an HTML table. Returns TRUE or FALSE.

Příklad 1. Prepare a statement, execute, and view the result

<?php $conn = ovrimos_connect ("db_host", "8001", "admin", "password"); if ($conn != 0) { echo "Connection ok!"; $res = ovrimos_prepare ($conn, "select table_id, table_name from sys.tables where table_id = 7"); if ($res != 0) { echo "Prepare ok!"; if (ovrimos_execute ($res, array(3))) { echo "Execute ok!\n"; ovrimos_result_all ($res); } else { echo "Execute not ok!"; } ovrimos_free_result ($res); } else { echo "Prepare not ok!\n"; } ovrimos_close($conn); } ?>
This will execute an SQL statement and print the result in an HTML table.

Příklad 2. Ovrimos_result_all with meta-information

<?php $conn = ovrimos_connect ("db_host", "8001", "admin", "password"); if ($conn != 0) { echo "Connection ok!"; $res = ovrimos_exec ($conn, "select table_id, table_name from sys.tables where table_id = 1") if ($res != 0) { echo "Statement ok! cursor=".ovrimos_cursor ($res)."\n"; $colnb = ovrimos_num_fields ($res); echo "Output columns=".$colnb."\n"; for ($i=1; $i <= $colnb; $i++) { $name = ovrimos_field_name ($res, $i); $type = ovrimos_field_type ($res, $i); $len = ovrimos_field_len ($res, $i); echo "Column ".$i." name=".$name." type=".$type." len=".$len."\n"; } ovrimos_result_all ($res); ovrimos_free_result ($res); } ovrimos_close($conn); } ?>

Příklad 3. ovrimos_result_all example

<?php $conn = ovrimos_connect ("db_host", "8001", "admin", "password"); if ($conn != 0) { echo "Connection ok!"; $res = ovrimos_exec ($conn, "update test set i=5"); if ($res != 0) { echo "Statement ok!"; echo ovrimos_num_rows ($res)." rows affected\n"; ovrimos_free_result ($res); } ovrimos_close($conn); } ?>

ovrimos_result

(PHP 4 >= 4.0.3)

ovrimos_result -- Retrieves the output column

Description

int ovrimos_result ( int result_id, mixed field)

ovrimos_result() is used to retrieve the output column.

ovrimos_result() retrieves the output column specified by 'field', either as a string or as an 1-based index.

ovrimos_rollback

(PHP 4 >= 4.0.3)

ovrimos_rollback -- Rolls back the transaction

Description

int ovrimos_rollback ( int connection_id)

ovrimos_rollback() is used to roll back the transaction.

ovrimos_rollback() rolls back the transaction.

LXXIV. Output Control funkce

Output Control funkce (funkce pro řízení výstupu) vám umožňujíc ovládat, kdy se odešle výstup skriptu. To může být užitečné v několika různých situacích, zvláště pokud potřebujete poslat browseru hlavičky poté, co váš skript začal odesílat data. Output Control funkce neovlivňují hlavičky odeslané pomocí header() nebo setcookie(), pouze funkce jako echo() a data mezi bloky PHP kódu.

Příklad 1. Ukázka řízení výstupu

<?php ob_start(); echo "Hello\n"; setcookie ("cookiename", "cookiedata"); ob_end_flush(); ?>

Ve výše uvedené ukázce se výstup z echo() uloží ve výstupním bufferu až do volání ob_end_flush(). Mezitím volání setcookie() úspěšně uložilo cookie bez vyvolání chyby. (Normálně nemůžete odeslat do browseru hlavičky poté, co už byla odeslána data.)

Viz také header() a setcookie().

Obsah
flush -- Odeslat výstupní buffer
ob_clean -- Clean (erase) the output buffer
ob_end_clean -- Vyčistit (vymazat) výstupní buffer a vypnout bufferování výstupu
ob_end_flush -- Vyprázdnit (odeslat) výstupní buffer a vypnout bufferování výstupu
ob_flush -- Flush (send) the output buffer
ob_get_contents -- Vrátit obsah výstupního bufferu
ob_get_length -- Vrátit délku výstupního buffer
ob_get_level -- Return the nesting level of the output buffering mechanism
ob_get_status -- Get status of output buffers
ob_gzhandler -- ob_start callback function to gzip output buffer
ob_implicit_flush -- Vypnout/zapnout implicitní flush
ob_start -- Zapnout bufferování výstupu

flush

(PHP 3, PHP 4 )

flush -- Odeslat výstupní buffer

Popis

void flush ( void)

Vyprázdní výstupní buffery PHP a jakéhokoli backendu, který PHP používá (CGI, web server, atd.) Odešle veškerý dosavadní výstup do uživatelova browseru.

Poznámka: flush() nemá žádný účinek na bufferovací schéma vašeho webserveru nebo browseru na klientské straně.

Některé servery, zvláště na Win32, bufferují výstup až do ukončení běhu skriptu bez ohledu na flush(), a až potom odešlou výstup browseru.

Browser může také bufferovat svůj vstup před zobrazením. Například Netscape bufferuje text do té doby než přijme konec řádku nebo začátek tagu, a nezobrazí tabulku, dokud nedostane </table> nejzevnější tabulky.

ob_get_level

(PHP 4 >= 4.2.0)

ob_get_level -- Return the nesting level of the output buffering mechanism

Description

int ob_get_level ( void)

This will return the level of nested output buffering handlers.

ob_get_status

(PHP 4 >= 4.2.0)

ob_get_status -- Get status of output buffers

Description

array ob_get_status ( [bool full_status])

Varování

This will return the current status of output buffers. It returns array contains buffer status or FALSE for error.

ob_gzhandler

(PHP 4 >= 4.0.4)

ob_gzhandler -- ob_start callback function to gzip output buffer

Description

string ob_gzhandler ( string buffer [, int mode])

Poznámka: mode was added in PHP 4.0.5.

ob_gzhandler() is intended to be used as a callback function for ob_start() to help facilitate sending gz-encoded data to web browsers that support compressed web pages. Before ob_gzhandler() actually sends compressed data, it determines what type of content encoding the browser will accept ("gzip", "deflate" or none at all) and will return it's output accordingly. All browsers are supported since it's up to the browser to send the correct header saying that it accepts compressed web pages.

Příklad 1. ob_gzhandler() Example

<?php ob_start("ob_gzhandler"); ?> <html> <body> <p>This should be a compressed page. </html> <body>

See also ob_start() and ob_end_flush().

ob_implicit_flush

(PHP 4 )

ob_implicit_flush -- Vypnout/zapnout implicitní flush

Popis

void ob_implicit_flush ( [int flag])

ob_implicit_flush() vypne nebo zapne implicitní flushování (pokud nedostane žádný flag, default je zapnout). Implicitní flushování způsobí flush po každém vygenerování výstupu, takže už nebudou potřeba explicitní volání flush().

Zapnutí implicitního flushování zruší bufferování výstupu, a aktuální obsah výstupních bufferů se odešle jako při volání ob_end_flush().

Viz také flush(), ob_start() a ob_end_flush().

ob_start

(PHP 4 )

ob_start -- Zapnout bufferování výstupu

Popis

void ob_start ( [string output_callback])

Tato funkce zapíná bufferování výstupu. Pokud je bufferování výstupu aktivováno, žádný výstup ze skriptu se neodešle, místo toho se ukládá v interním bufferu.

Obsah tohoto interního bufferu je možno zkopírovat do proměnné typu string pomocí ob_get_contents(). K odeslání obsahu interního bufferu použijte ob_end_flush(). Naprotitomu ob_end_clean() tiše odstraní obsah výstupního bufferu.

Můžete zadat volitelný název callback funkce, která se automaticky zavolá s obsahem bufferu jako argumentem. Tato funkce musí přijímat řetězec a vracet řetězec. Tato funkce bude volána při ob_end_flush() a dostane obsah výstupního bufferu jako svůj argument. Musí vrátit nový výstupní buffer, který se pak vytiskne.

Výstupní buffery se dají stackovat, tzn. můžete zavolat ob_start() zatímco je aktivní další ob_start(). Je potřeba pouze správný počet volání ob_end_flush()(). Pokud je akivních více output callback funkcí, výstup je filtrován postupně přes každou z nich tak jak jsou do sebe vnořené.

Příklad 1. Ukázka callback funkce

<?php
function c($str) {
  // Druu Chunusun mut dum Kuntrubuß...
  return nl2br(ereg_replace("[aeiou]", "u", $str));
}

function d($str) {
  return strip_tags($str);
}
?>

<?php ob_start("c"); ?>
Drei Chinesen mit dem Kontrabaß...
<?php ob_start("d"); ?>
<h1>..saßen auf der Straße und erzählten sich was...</h1>
<?php ob_end_flush(); ?>
... da kam die Polizei, ja was ist denn das?
<?php ob_end_flush(); ?>

?>

Viz také ob_get_contents(), ob_end_flush(), ob_end_clean(), and ob_implicit_flush()

LXXV. Object property and method call overloading

Varování

The purpose of this extension is to allow overloading of object property access and method calls. Only one function is defined in this extension, overload() which takes the name of the class that should have this functionality enabled. The class named has to define appropriate methods if it wants to have this functionality: __get(), __set() and __call() respectively for getting/setting a property, or calling a method. This way overloading can be selective. Inside these handler functions the overloading is disabled so you can access object properties normally.

Some simple examples on using the overload() function:

Příklad 1. Overloading a PHP class

<?php class OO { var $a = 111; var $elem = array('b' => 9, 'c' => 42); // Callback method for getting a property function __get($prop_name, &$prop_value) { if (isset($this->elem[$prop_name])) { $prop_value = $this->elem[$prop_name]; return true; } else { return false; } } // Callback method for setting a property function __set($prop_name, $prop_value) { $this->elem[$prop_name] = $prop_value; return true; } } // Here we overload the OO object overload('OO'); $o = new OO; print "\$o->a: $o->a\n"; // print: $o->a: print "\$o->b: $o->b\n"; // print: $o->b: 9 print "\$o->c: $o->c\n"; // print: $o->c: 42 print "\$o->d: $o->d\n"; // print: $o->d: // add a new item to the $elem array in OO $o->x = 56; // instantiate stdclass (it is built-in in PHP 4) // $val is not overloaded! $val = new stdclass; $val->prop = 555; // Set "a" to be an array with the $val object in it // But __set() will put this in the $elem array $o->a = array($val); var_dump($o->a[0]->prop); ?>

Varování

As this is an experimental extension, not all things work. There is no __call() support currently, you can only overload the get and set operations for properties. You cannot invoke the original overloading handlers of the class, and __set() only works to one level of property access.

Obsah
overload -- Enable property and method call overloading for a class

overload

(PHP 4 >= 4.2.0)

overload -- Enable property and method call overloading for a class

Description

void overload ( [string class_name])

The overload() function will enable property and method call overloading for a class identified by class_name. See an example in the introductory section of this part.

LXXVI. PDF funkce

Introduction

Pokud máte PDF knihovnu od Thomase Merze (dostupná z http://www.pdflib.com/pdflib/index.html), můžete používat PDF funkce na tvorbu PDF souborů; ke kompilaci budete potřebovat také JPEG knihovnu a TIFF knihovnu. Tyto dvě knihovny poměrně často dělají potíže při konfiguraci PHP. Při řešení případných problémů se řiďte chybovými zprávami configure skriptu.

Věnujte prosím pozornost výborné dokumentaci pdflib, která je součástí distribuce zdrojového kódu. Poskytuje velmi dobrý přehled schopností pdflib. Většina funkcí pdflib a příslušného PHP modulu má stejné jméno. Argumenty jsou také identické. Pokud chcete tento modul využívat opravdu efektivně, měli byste chápat také některé z konceptů PDF nebo Postscriptu. Všechny rozměry a koordináty se udávají v Postscriptových bodech. Obecně je 72 PostScriptových bodů na palec, ale závisí to na výstupním rozlišení.

Existuje další PHP modul na tvorbu PDF dokumentů, založený na ClibPDF od firmy FastIO. Má mírně jinou API. Detaily viz ClibPDF funkce.

Tento PDF modul zavádí nový typ proměnné. Nazývá se pdfdoc. pdfdoc je pointer na PDF dokument a téměř všechny funkce ho vyžadují jako svůj první argument.

Zmatek se starými verzemi pdflib

Od úplného začátky podpory PDF v PHP — od pdflib 0.6 — došlo k mnoha změnám zvláště v API pdflib. Většinu těchto změn PHP nějak zakrylo, některé vyžadovaly změnu PHP API. Od pdflib 3.x se API snad stabilizovala, a PHP 4 přijala tuto verzi jako mimimální pro podporu PDF. Následkem toho mnoho funkcí dříve či později zmizí nebo bude nahraženo alternativami. Podpora pdflib 0.6 už byla naprosto ukončena. Následující tabulka vyjmenovává všechny funkce, které jsou od PHP 4.0.2 zastaralé a měly by být nahraženy jejich novějšími verzemi.

Tabulka 1. Zastaralé funkce a jejich náhrady

Stará funkce	Náhrada
pdf_put_image()	Není potřeba.
pdf_get_font()	pdf_get_value() s `"font"` jako druhý argument.
pdf_get_fontsize()	pdf_get_value() s `"fontsize"` jako druhý argument.
pdf_get_fontname()	pdf_get_parameter() s `"fontname"` jako druhý argument.
pdf_set_info_creator()	pdf_set_info() s `"Creator"` jako druhý argument.
pdf_set_info_title()	pdf_set_info() s `"Title"` jako druhý argument.
pdf_set_info_subject()	pdf_set_info() s `"Subject"` jako druhý argument.
pdf_set_info_author()	pdf_set_info() s `"Author"` jako druhý argument.
pdf_set_info_keywords()	pdf_set_info() s `"Keywords"` jako druhý argument.
pdf_set_leading()	pdf_set_value() s `"leading"` jako druhý argument.
pdf_set_text_rendering()	pdf_set_value() s `"textrendering"` jako druhý argument.
pdf_set_text_rise()	pdf_set_value() s `"textrise"` jako druhý argument.
pdf_set_horiz_scaling()	pdf_set_value() s `"horizscaling"` jako druhý argument.
pdf_set_text_matrix()	neexistuje
pdf_set_char_spacing()	pdf_set_value() s `"charspacing"` jako druhý argument.
pdf_set_word_spacing()	pdf_set_value() s `"wordspacing"` jako druhý argument.
pdf_set_transition()	pdf_set_parameter() s `"transition"` jako druhý argument.
pdf_set_duration()	pdf_set_value() s `"duration"` jako druhý argument.
pdf_open_gif()	pdf_open_image_file() s `"gif"` jako druhý argument.
pdf_open_jpeg()	pdf_open_image_file() s `"jpeg"` jako druhý argument.
pdf_open_tiff()	pdf_open_image_file() s `"tiff"` jako druhý argument.
pdf_open_png()	pdf_open_image_file() s `"png"` jako druhý argument.
pdf_get_imagewidth()	pdf_get_value() s `"imagewidth"` jako druhý argument a obrázkem jako třetí argument.
pdf_get_imageheight()	pdf_get_value() s `"imageheight"` jako druhý argument a obrázkem jako třetí argument.
()	()

Rady pro instalaci pdflib 3.x

Od pdflib 3.0 by se pdflib měla konfigurovat s volbou --enable-shared-pdflib.

Problémy se staršími verzemi pdflib

Pokud používáte pdflib 2.01, zkontrolujte, jak je tato knihovna nainstalována. Měli byste mít soubor libpdf.so, nebo link na něj. Verze 2.01 vytváří soubor libpdf2.01.so, který se nedá najít při linkování testovacího souboru v configure. Budete muset vytvořit symbolický link z libpdf.so na libpdf2.01.so.

Ve verzi 2.20 přibyly další změny v API pdflib a podpora čínských a japonských fontů. Pokud používáte pdflib 2.20 buďte opatrní při generování PDF dokumentů v paměti. Do verze pdflib 3.0 by mohlo být nestabilní. Argument kódování v pdf_set_font() se změnil na řetězec. To znamená, že místo např. 4 musíte použít 'winansi'.

Pokud používáte pdflib 2.30, nemáte k dispozici pdf_set_text_matrix(). Přestala být podporována. Obecnou radou je zjistit si případné změny v release notes používané verze pdflib.

Žádná verze PHP 4 od data 9. března 2000 nepodporuje podflib starší než 3.0. Na druhou stranu, PHP 3 by se nemělo používat s novější verzí pdflib než 2.01.

Ukázky

Většina funkcí se používá docela snadno. Nejtěžší je zřejmě vůbec nějaký jednoduchý PDF dokument vůbec vytvořit. Následující ukázka by měla pomoci začít. Vytvoří soubor test.pdf s jednou stránkou. Tato stránka obsahuje text "Times Roman outlined" napsaný 30ti bodovým obrysem. Text je také podtržený.

Příklad 1. Tvorba PDF dokumentu s pdflib

<?php $fp = fopen("test.pdf", "w"); $pdf = pdf_open($fp); pdf_set_info($pdf, "Author", "Uwe Steinmann"); pdf_set_info($pdf, "Title", "Test for PHP wrapper of PDFlib 2.0"); pdf_set_info($pdf, "Creator", "See Author"); pdf_set_info($pdf, "Subject", "Testing"); pdf_begin_page($pdf, 595, 842); pdf_add_outline($pdf, "Page 1"); pdf_set_font($pdf, "Times-Roman", 30, "host"); pdf_set_value($pdf, "textrendering", 1); pdf_show_xy($pdf, "Times Roman outlined", 50, 750); pdf_moveto($pdf, 50, 740); pdf_lineto($pdf, 330, 740); pdf_stroke($pdf); pdf_end_page($pdf); pdf_close($pdf); fclose($fp); echo "<A HREF=getpdf.php>finished</A>"; ?>

Skript getpdf.php pouze vrátí vytvořený pdf dokument.

<?php $fp = fopen("test.pdf", "r"); header("Content-type: application/pdf"); fpassthru($fp); fclose($fp); ?>

Distribuce pdflib obsahuje rozsáhlejší ukázku, která obsahuje sérii stránek s analogovými hodinami. Tato ukázka převedená do PHP vypadá takto (stejnou ukázku najdete v dokumentaci k clibpdf modulu):

Příklad 2. pdfclock ukázka z pdflib distribuce

<?php $pdffilename = "clock.pdf"; $radius = 200; $margin = 20; $pagecount = 40; $fp = fopen($pdffilename, "w"); $pdf = pdf_open($fp); pdf_set_info($pdf, "Creator", "pdf_clock.php3"); pdf_set_info($pdf, "Author", "Uwe Steinmann"); pdf_set_info($pdf, "Title", "Analog Clock"); while($pagecount-- > 0) { pdf_begin_page($pdf, 2 * ($radius + $margin), 2 * ($radius + $margin)); pdf_set_parameter($pdf, "transition", "wipe"); pdf_set_value($pdf, "duration", 0.5); pdf_translate($pdf, $radius + $margin, $radius + $margin); pdf_save($pdf); pdf_setrgbcolor($pdf, 0.0, 0.0, 1.0); /* minute strokes */ pdf_setlinewidth($pdf, 2.0); for ($alpha = 0; $alpha < 360; $alpha += 6) { pdf_rotate($pdf, 6.0); pdf_moveto($pdf, $radius, 0.0); pdf_lineto($pdf, $radius-$margin/3, 0.0); pdf_stroke($pdf); } pdf_restore($pdf); pdf_save($pdf); /* 5 minute strokes */ pdf_setlinewidth($pdf, 3.0); for ($alpha = 0; $alpha < 360; $alpha += 30) { pdf_rotate($pdf, 30.0); pdf_moveto($pdf, $radius, 0.0); pdf_lineto($pdf, $radius-$margin, 0.0); pdf_stroke($pdf); } $ltime = getdate(); /* draw hour hand */ pdf_save($pdf); pdf_rotate($pdf,-(($ltime['minutes']/60.0)+$ltime['hours']-3.0)*30.0); pdf_moveto($pdf, -$radius/10, -$radius/20); pdf_lineto($pdf, $radius/2, 0.0); pdf_lineto($pdf, -$radius/10, $radius/20); pdf_closepath($pdf); pdf_fill($pdf); pdf_restore($pdf); /* draw minute hand */ pdf_save($pdf); pdf_rotate($pdf,-(($ltime['seconds']/60.0)+$ltime['minutes']-15.0)*6.0); pdf_moveto($pdf, -$radius/10, -$radius/20); pdf_lineto($pdf, $radius * 0.8, 0.0); pdf_lineto($pdf, -$radius/10, $radius/20); pdf_closepath($pdf); pdf_fill($pdf); pdf_restore($pdf); /* draw second hand */ pdf_setrgbcolor($pdf, 1.0, 0.0, 0.0); pdf_setlinewidth($pdf, 2); pdf_save($pdf); pdf_rotate($pdf, -(($ltime['seconds'] - 15.0) * 6.0)); pdf_moveto($pdf, -$radius/5, 0.0); pdf_lineto($pdf, $radius, 0.0); pdf_stroke($pdf); pdf_restore($pdf); /* draw little circle at center */ pdf_circle($pdf, 0, 0, $radius/30); pdf_fill($pdf); pdf_restore($pdf); pdf_end_page($pdf); } $pdf = pdf_close($pdf); fclose($fp); echo "<A HREF=getpdf.php?filename=".$pdffilename.">finished</A>"; ?>

PHP skript getpdf.php pouze vrátí výtvořený PDF dokument.

<?php $fp = fopen($filename, "r"); header("Content-type: application/pdf"); fpassthru($fp); fclose($fp); ?>

Obsah
pdf_add_annotation -- Adds annotation
pdf_add_bookmark -- Adds bookmark for current page
pdf_add_launchlink -- Add a launch annotation for current page
pdf_add_locallink -- Add a link annotation for current page
pdf_add_note -- Add a note annotation for current page
pdf_add_outline -- Adds bookmark for current page
pdf_add_pdflink -- Adds file link annotation for current page
pdf_add_thumbnail -- Adds thumbnail for current page
pdf_add_weblink -- Adds weblink for current page
pdf_arc -- Draws an arc
pdf_arcn -- Draws an arc (clockwise)
pdf_attach_file -- Adds a file attachement for current page
pdf_begin_page -- Začít novou stranu
pdf_begin_pattern -- Starts new pattern
pdf_begin_template -- Starts new template
pdf_circle -- Draws a circle
pdf_clip -- Clips to current path
pdf_close_image -- Closes an image
pdf_close_pdi_page -- Close the page handle
pdf_close_pdi -- Close the input PDF document
pdf_close -- Zavřít PDF dokument
pdf_closepath_fill_stroke -- Closes, fills and strokes current path
pdf_closepath_stroke -- Closes path and draws line along path
pdf_closepath -- Closes path
pdf_concat -- Concatenate a matrix to the CTM
pdf_continue_text -- Outputs text in next line
pdf_curveto -- Draws a curve
pdf_delete -- Deletes a PDF object
pdf_end_page -- Ukončit stranu
pdf_end_pattern -- Finish pattern
pdf_end_template -- Finish template
pdf_endpath -- Ends current path
pdf_fill_stroke -- Fills and strokes current path
pdf_fill -- Fills current path
pdf_findfont -- Prepare font for later use with pdf_setfont().
pdf_get_buffer -- Fetch the buffer containig the generated PDF data.
pdf_get_font -- Deprecated: font handling
pdf_get_fontname -- Deprecated: font handling
pdf_get_fontsize -- Deprecated: font handling
pdf_get_image_height -- Returns height of an image
pdf_get_image_width -- Returns width of an image
pdf_get_majorversion -- Returns the major version number of the PDFlib
pdf_get_minorversion -- Returns the minor version number of the PDFlib
pdf_get_parameter -- Zjistit hodnotu parametru
pdf_get_pdi_parameter -- Get some PDI string parameters
pdf_get_pdi_value -- Gets some PDI numerical parameters
pdf_get_value -- Gets certain numerical value
pdf_initgraphics -- Resets graphic state
pdf_lineto -- Draws a line
pdf_makespotcolor -- Makes a spotcolor
pdf_moveto -- Sets current point
pdf_new -- Creates a new pdf object
pdf_open_CCITT -- Opens a new image file with raw CCITT data
pdf_open_file -- Opens a new pdf object
pdf_open_gif -- Opens a GIF image
pdf_open_image_file -- Reads an image from a file
pdf_open_image -- Versatile function for images
pdf_open_jpeg -- Opens a JPEG image
pdf_open_memory_image -- Opens an image created with PHP's image functions
pdf_open_pdi_page -- Prepare a page
pdf_open_pdi -- Opens a PDF file
pdf_open_png -- Opens a PNG image
pdf_open_tiff -- Opens a TIFF image
pdf_open -- Otevřít nový PDF dokument
pdf_place_image -- Places an image on the page
pdf_place_pdi_page -- Places an image on the page
pdf_rect -- Draws a rectangle
pdf_restore -- Restores formerly saved environment
pdf_rotate -- Sets rotation
pdf_save -- Saves the current environment
pdf_scale -- Sets scaling
pdf_set_border_color -- Sets color of border around links and annotations
pdf_set_border_dash -- Sets dash style of border around links and annotations
pdf_set_border_style -- Sets style of border around links and annotations
pdf_set_char_spacing -- Sets character spacing
pdf_set_duration -- Sets duration between pages
pdf_set_font -- Určit font a velikost
pdf_set_horiz_scaling -- Sets horizontal scaling of text
pdf_set_info_author -- Fills the author field of the document
pdf_set_info_creator -- Fills the creator field of the document
pdf_set_info_keywords -- Fills the keywords field of the document
pdf_set_info_subject -- Fills the subject field of the document
pdf_set_info_title -- Fills the title field of the document
pdf_set_info -- Vyplnit položku informací o dokumentu
pdf_set_leading -- Nastavit vzdálenost mezi řádky
pdf_set_parameter -- Nastavit určité parametry
pdf_set_text_matrix -- Sets the text matrix
pdf_set_text_pos -- Sets text position
pdf_set_text_rendering -- Determines how text is rendered
pdf_set_text_rise -- Sets the text rise
pdf_set_value -- Sets certain numerical value
pdf_set_word_spacing -- Sets spacing between words
pdf_setcolor -- Sets fill and stroke color
pdf_setdash -- Sets dash pattern
pdf_setflat -- Sets flatness
pdf_setfont -- Set the current font
pdf_setgray_fill -- Sets filling color to gray value
pdf_setgray_stroke -- Sets drawing color to gray value
pdf_setgray -- Sets drawing and filling color to gray value
pdf_setlinecap -- Sets linecap parameter
pdf_setlinejoin -- Sets linejoin parameter
pdf_setlinewidth -- Sets line width
pdf_setmatrix -- Sets current transformation matrix
pdf_setmiterlimit -- Sets miter limit
pdf_setpolydash -- Sets complicated dash pattern
pdf_setrgbcolor_fill -- Sets filling color to rgb color value
pdf_setrgbcolor_stroke -- Sets drawing color to rgb color value
pdf_setrgbcolor -- Sets drawing and filling color to rgb color value
pdf_show_boxed -- Vytisknout text v rámečku
pdf_show_xy -- Vytisknout text na určené pozici
pdf_show -- Umístit text na aktuální pozici
pdf_skew -- Skews the coordinate system
pdf_stringwidth -- Returns width of text using current font
pdf_stroke -- Draws line along path
pdf_translate -- Sets origin of coordinate system

Unfortunately pdflib does not make a copy of the string, which forces PHP to allocate the memory. Currently this piece of memory is not been freed by any PDF function but it will be taken care of by the PHP memory manager.

pdf_add_pdflink

(PHP 3>= 3.0.12, PHP 4 )

pdf_add_pdflink -- Adds file link annotation for current page

Description

int pdf_add_pdflink ( int pdf object, float llx, float lly, float urx, float ury, string filename, int page, string dest)

Add a file link annotation (to a PDF target).

pdf_add_thumbnail

(PHP 4 >= 4.0.5)

pdf_add_thumbnail -- Adds thumbnail for current page

Description

int pdf_add_thumbnail ( int pdf object, int image)

Add an existing image as thumbnail for the current page.

pdf_add_weblink

(PHP 3>= 3.0.12, PHP 4 )

pdf_add_weblink -- Adds weblink for current page

Description

int pdf_add_weblink ( int pdf object, float llx, float lly, float urx, float ury, string url)

Add a weblink annotation to a target URL on the Web.

pdf_arc

(PHP 3>= 3.0.6, PHP 4 )

pdf_arc -- Draws an arc

Popis

void pdf_arc ( int pdf document, double x-coor, double y-coor, double radius, double start, double end)

Funkce pdf_arc() function draws an arc with center at point (x-coor, y-coor) and radius radius, starting at angle start and ending at angle end.

Viz také pdf_circle(), pdf_stroke().

pdf_arcn

(PHP 4 >= 4.0.5)

pdf_arcn -- Draws an arc (clockwise)

Description

void pdf_arc ( resource pdf object, float x, float y, float r, float alpha, float beta)

Draw a clockwise circular arc from alpha to beta degrees

pdf_attach_file

(PHP 4 >= 4.0.5)

pdf_attach_file -- Adds a file attachement for current page

Description

int pdf_attach_file ( int pdf object, float llx, float lly, float urx, float ury, string filename, string description, string author, string mimetype, string icon)

Add a file attachment annotation. icon is one of "graph, "paperclip", "pushpin", or "tag".

pdf_begin_page

(PHP 3>= 3.0.6, PHP 4 )

pdf_begin_page -- Začít novou stranu

Popis

void pdf_begin_page ( int pdf document, double width, double height)

Funkce pdf_begin_page() začne novou stránku s výškou height a šířkou width. Pokud chcete vytvořit validní dokument, musíte zavolat tuto funkci a pdf_end_page() přinejmenším jednou.

Viz také pdf_end_page().

pdf_begin_pattern

(PHP 4 >= 4.0.5)

pdf_begin_pattern -- Starts new pattern

void pdf_closepath ( int pdf document)

Funkce pdf_closepath() function closes the current path. This means, it draws a line from current point to the point where the first line was started. Many functions like pdf_moveto(), pdf_circle() and pdf_rect() start a new path.

pdf_concat

(PHP 4 >= 4.0.5)

pdf_concat -- Concatenate a matrix to the CTM

Description

void pdf_concat ( int pdf object, float a, float b, float c, float d, float e, float f)

Concatenate a matrix to the CTM.

pdf_continue_text

(PHP 3>= 3.0.6, PHP 4 )

pdf_continue_text -- Outputs text in next line

Popis

void pdf_continue_text ( int pdf document, string text)

Funkce pdf_continue_text() function outputs the string in text in the next line. The distance between the lines can be set with pdf_set_leading().

Viz také pdf_show_xy(), pdf_set_leading(), pdf_set_text_pos().

pdf_curveto

(PHP 3>= 3.0.6, PHP 4 )

pdf_curveto -- Draws a curve

Popis

void pdf_curveto ( int pdf document, double x1, double y1, double x2, double y2, double x3, double y3)

Funkce pdf_curveto() function draws a Bezier curve from the current point to the point (x3, y3) using (x1, y1) and (x2, y2) as control points.

Viz také pdf_moveto(), pdf_lineto(), pdf_stroke().

pdf_delete

(PHP 4 >= 4.0.5)

pdf_delete -- Deletes a PDF object

Description

void pdf_delete ( int pdf object)

Delete the PDF object, and free all internal resources.

pdf_end_page

(PHP 3>= 3.0.6, PHP 4 )

pdf_end_page -- Ukončit stranu

Popis

void pdf_end_page ( int pdf document)

Funkce pdf_end_page() ukončí stranu. Jakmile je strana ukončena, nedá se už upravovat.

Viz také pdf_begin_page().

pdf_end_pattern

(PHP 4 >= 4.0.5)

pdf_end_pattern -- Finish pattern

Description

void pdf_end_pattern ( int pdf object)

Finish the pattern definition.

pdf_end_template

(PHP 4 >= 4.0.5)

pdf_end_template -- Finish template

Description

void pdf_end_template ( int pdf object)

Finish the template definition.

pdf_endpath

(PHP 3>= 3.0.6, PHP 4 )

pdf_endpath -- Ends current path

Popis

void pdf_endpath ( int pdf document)

Funkce pdf_endpath() function ends the current path but does not close it.

Viz také pdf_closepath().

pdf_fill_stroke

(PHP 3>= 3.0.6, PHP 4 )

pdf_fill_stroke -- Fills and strokes current path

Popis

void pdf_fill_stroke ( int pdf document)

Funkce pdf_fill_stroke() function fills the interior of the current path with the current fill color and draws current path.

Viz také pdf_closepath(), pdf_stroke(), pdf_fill(), pdf_setgray_fill(), pdf_setgray(), pdf_setrgbcolor_fill(), pdf_setrgbcolor().

pdf_fill

(PHP 3>= 3.0.6, PHP 4 )

pdf_fill -- Fills current path

Popis

void pdf_fill ( int pdf document)

Funkce pdf_fill() function fills the interior of the current path with the current fill color.

Viz také pdf_closepath(), pdf_stroke(), pdf_setgray_fill(), pdf_setgray(), pdf_setrgbcolor_fill(), pdf_setrgbcolor().

pdf_findfont

(PHP 4 >= 4.0.5)

pdf_findfont -- Prepare font for later use with pdf_setfont().

Description

See pdf_get_value().

pdf_get_image_height

(PHP 3>= 3.0.12, PHP 4 )

pdf_get_image_height -- Returns height of an image

Popis

string pdf_get_image_height ( int pdf document, int image)

Funkce pdf_get_image_height() function returns the heights of a pdf image in pixel.

Viz také pdf_open_image_file(), pdf_open_memory_image(), pdf_get_image_width().

pdf_get_image_width

(PHP 3>= 3.0.12, PHP 4 )

pdf_get_image_width -- Returns width of an image

Popis

string pdf_get_image_width ( int pdf document, int image)

Funkce pdf_get_image_width() function returns the widths of a pdf image in pixel.

Viz také pdf_open_image_file(), pdf_open_memory_image(), pdf_get_image_height().

pdf_get_majorversion

(PHP 4 >= 4.2.0)

pdf_get_majorversion -- Returns the major version number of the PDFlib

Description

int pdf_get_majorversion ( void)

Returns the major version number of the PDFlib.

pdf_get_minorversion

(PHP 4 >= 4.2.0)

pdf_get_minorversion -- Returns the minor version number of the PDFlib

Description

int pdf_get_majorversion ( void)

Returns the minor version number of the PDFlib.

pdf_get_parameter

(PHP 4 >= 4.0.1)

pdf_get_parameter -- Zjistit hodnotu parametru

Popis

string pdf_get_parameter ( int pdf document, string name [, double modifier])

Funkce pdf_get_parameter() function gets several parameters of pdflib which are of the type string. The function parameter modifier characterizes the parameter to get. If the modifier is not needed it has to be 0 or not passed at all.

Viz také pdf_get_value(), pdf_set_value(), pdf_set_parameter().

pdf_get_pdi_parameter

(PHP 4 >= 4.0.5)

pdf_get_pdi_parameter -- Get some PDI string parameters

int pdf_open_file ( int pdf object [, string filename])

Create a new PDF file using the supplied file name. If filename is empty the PDF document will be generated in memory instead of on file. The result must be fetched by the client with the pdf_get_buffer() function.

The following example shows how to create a pdf document in memory and how to output it correctly.

Příklad 1. Creating a PDF document in memory

<?php $pdf = pdf_new(); pdf_open_file($pdf); pdf_begin_page($pdf, 595, 842); pdf_set_font($pdf, "Times-Roman", 30, "host"); pdf_set_value($pdf, "textrendering", 1); pdf_show_xy($pdf, "A PDF document created in memory!", 50, 750); pdf_end_page($pdf); pdf_close($pdf); $data = pdf_get_buffer($pdf); header("Content-type: application/pdf"); header("Content-disposition: inline; filename=test.pdf"); header("Content-length: " . strlen($data)); echo $data; ?>

pdf_open_gif

(PHP 3>= 3.0.7, PHP 4 )

pdf_open_gif -- Opens a GIF image

Popis

int pdf_open_gif ( int pdf document, string filename)

Funkce pdf_open_gif() function opens an image stored in the file with the name filename. The format of the image has to be gif. The function returns a pdf image identifier.

Poznámka: This function shouldn't be used anymore. Please use the function pdf_open_image_file() instead.

Příklad 1. Including a gif image

<?php
$im = pdf_open_gif($pdf, "test.gif");
pdf_place_image($pdf, $im, 100, 100, 1);
pdf_close_image($pdf, $im);
?>

Viz také pdf_close_image(), pdf_open_jpeg(), pdf_open_memory_image(), pdf_execute_image(), pdf_place_image(), pdf_put_image().

pdf_open_image_file

(PHP 3 CVS only, PHP 4 )

pdf_open_image_file -- Reads an image from a file

Popis

int pdf_open_image_file ( int PDF-document, string format, string filename)

The function pdf_open_image_file() reads an image of format format from the file filename. Possible formats are 'png', 'tiff', 'jpeg' and 'gif'. The function returns a pdf image identifier.

Příklad 1. Inserting an image

<?php $pim = pdf_open_image_file($pdf, "png", "picture.png"); pdf_place_image($pdf, $pim, 100, 100, 1); pdf_close_image($pdf, $pim); ?>

Viz také pdf_close_image(), pdf_open_jpeg(), pdf_open_gif(), pdf_open_tiff(), pdf_open_png(), pdf_execute_image(), pdf_place_image(), pdf_put_image().

pdf_open_image

(PHP 4 >= 4.0.5)

pdf_open_image -- Versatile function for images

Description

int pdf_open_image ( int PDF-document, string imagetype, string source, string data, long length, int width, int height, int components, int bpc, string params)

Use image data from a variety of data sources. Supported types are "jpeg", "ccitt", "raw". Supported sources are "memory", "fileref", "url". len is only used for type="raw", params is only used for type="ccitt".

pdf_open_jpeg

(PHP 3>= 3.0.7, PHP 4 )

pdf_open_jpeg -- Opens a JPEG image

Popis

int pdf_open_jpeg ( int pdf document, string filename)

Funkce pdf_open_jpeg() function opens an image stored in the file with the name filename. The format of the image has to be jpeg. The function returns a pdf image identifier.

Poznámka: This function shouldn't be used anymore. Please use the function pdf_open_image_file() instead.

Viz také pdf_close_image(), pdf_open_gif(), pdf_open_png(), pdf_open_memory_image(), pdf_execute_image(), pdf_place_image(), pdf_put_image().

pdf_open_memory_image

(PHP 3>= 3.0.10, PHP 4 )

pdf_open_memory_image -- Opens an image created with PHP's image functions

Popis

int pdf_open_memory_image ( int pdf document, int image)

Funkce pdf_open_memory_image() function takes an image created with the PHP's image functions and makes it available for the PDF dokument. The function returns a pdf image identifier.

Příklad 1. Including a memory image

<?php $im = ImageCreate(100, 100); $col = ImageColorAllocate($im, 80, 45, 190); ImageFill($im, 10, 10, $col); $pim = pdf_open_memory_image($pdf, $im); ImageDestroy($im); pdf_place_image($pdf, $pim, 100, 100, 1); pdf_close_image($pdf, $pim); ?>

Viz také pdf_close_image(), pdf_open_jpeg(), pdf_open_gif(), pdf_open_png() pdf_execute_image(), pdf_place_image(), pdf_put_image().

pdf_open_pdi_page

(PHP 4 >= 4.0.5)

pdf_open_pdi_page -- Prepare a page

Description

int pdf_open_pdi_page ( int pdf object, int dochandle, int pagenumber, string pagelabel)

Prepare a page for later use with pdf_place_image()

pdf_open_pdi

(PHP 4 >= 4.0.5)

pdf_open_pdi -- Opens a PDF file

Description

int pdf_open_pdi ( int pdf object, string filename, string stringparam, int intparam)

Open an existing PDF document for later use.

pdf_open_png

(PHP 4 )

pdf_open_png -- Opens a PNG image

Popis

int pdf_open_png ( int pdf, string png_file)

Funkce pdf_open_png() function opens an image stored in the file with the name filename. The format of the image has to be png. The function returns a pdf image identifier.

Poznámka: This function shouldn't be used anymore. Please use the function pdf_open_image_file() instead.

Příklad 1. Including a PNG image

<?php
$im = pdf_open_png ($pdf, "test.png");
pdf_place_image ($pdf, $im, 100, 100, 1);
pdf_close_image ($pdf, $im);
?>

Viz také pdf_close_image(), pdf_open_jpeg(), pdf_open_gif(), pdf_open_memory_image(), pdf_execute_image(), pdf_place_image(), pdf_put_image().

pdf_open_tiff

(PHP 4 )

pdf_open_tiff -- Opens a TIFF image

Popis

int pdf_open_tiff ( int PDF-document, string filename)

Funkce pdf_open_tiff() function opens an image stored in the file with the name filename. The format of the image has to be tiff. The function returns a pdf image identifier.

Poznámka: This function shouldn't be used anymore. Please use the function pdf_open_image_file() instead.

Viz také pdf_close_image(), pdf_open_gif(), pdf_open_jpeg(), pdf_open_png(), pdf_open_memory_image(), pdf_execute_image(), pdf_place_image(), pdf_put_image().

pdf_open

(PHP 3>= 3.0.6, PHP 4 )

pdf_open -- Otevřít nový PDF dokument

Popis

int pdf_open ( int file)

Funkce pdf_open() otvírá nový PDF dokument. Odpovídající soubor musí být otevřen funkcí fopen() a jeho deskriptor předán jako argument file. Pokud této funkci nepředáte žádné argumenty, dokument bude vytvořen v paměti a vrácen stránku po stránce buď na stdout (standardní výstup) nebo do browseru.

Poznámka: Návratová hodnota je potřeba jako první argument pro všechny ostatní funkce zapisující do PDF dokumentu.

Viz také fopen(), pdf_close().

pdf_place_image

(PHP 3>= 3.0.7, PHP 4 )

pdf_place_image -- Places an image on the page

Popis

void pdf_place_image ( int pdf document, int image, double x-coor, double y-coor, double scale)

Funkce pdf_place_image() function places an image on the page at postion (x-coor, x-coor). The image can be scaled at the same time.

Viz také pdf_put_image().

pdf_place_pdi_page

(PHP 4 >= 4.0.6)

pdf_place_pdi_page -- Places an image on the page

void pdf_rotate ( int pdf document, double angle)

Funkce pdf_rotate() function sets the rotation in degress to angle.

pdf_save

(PHP 3>= 3.0.6, PHP 4 )

pdf_save -- Saves the current environment

Popis

void pdf_save ( int pdf document)

Funkce pdf_save() function saves the current environment. It works like the postscript command gsave. Very useful if you want to translate or rotate an object without effecting other objects. pdf_save() should always be followed by pdf_restore() to restore the environment before pdf_save().

Viz také pdf_restore().

pdf_scale

(PHP 3>= 3.0.6, PHP 4 )

pdf_scale -- Sets scaling

void pdf_set_font ( int pdf document, string font name, double size, string encoding [, int embed])

Funkce pdf_set_font() nastaví platný font, velikost, a kódování. Pokud používáte pdflib 0.6, budete muset poskytnout Adobe Font Metrics (afm soubory) pro daný font ve font cestě (default je ./fonts). Pokud používáte PHP 3 nebo pdflib ve verzi starší než 2.20, čtvrtý argument encoding může mít následující hodnoty: 0 = builtin, 1 = pdfdoc, 2 = macroman, 3 = macexpert, 4 = winansi. Při encoding větší než 4 a menší než 0 se použije winansi. Většinou je to správná volba. Pokud používáte PHP 4 a pdflib ve verzi >= 2.20, argument encoding se změnil na řetězec. Používejte 'winansi', 'builtin', 'host', 'macroman' atd. Pokud má poslední argument hodnotu 1, font se vloží do PDF dokumentu. Vložit font je obvykle dobrý napad, pokud tento font není příliš rozšířený a nemůžete zaručit, že osoba, která váš dokument čte, má přístup k fontům v dokumentu použitým. Font se vloží pouze jednou, i když voláte pdf_set_font() několikrát.

Poznámka: Pokud se má vytvořit validní PDF dokument, tato funkce se musí volat až po pdf_begin_page().

Poznámka: Pokud v .upr souboru odkazujete na nějaký font, ujistěte se, že jméno v afm souboru a jméno fontu jsou stejné. Jinak se font vloží vícekrát. (Díky Paulu Haddonovi za toto zjištění.)

void pdf_set_value ( int pdf document, string name, double value)

Funkce pdf_set_value() function sets several numerical parameters of pdflib.

Viz také pdf_get_value(), pdf_get_parameter(), pdf_set_parameter().

pdf_set_word_spacing

(PHP 3>= 3.0.6, PHP 4 )

pdf_set_word_spacing -- Sets spacing between words

Popis

void pdf_set_word_spacing ( int pdf document, double space)

Funkce pdf_set_word_spacing() function sets the spacing between words.

Viz také pdf_set_char_spacing(), pdf_set_leading().

pdf_setcolor

(PHP 4 >= 4.0.5)

pdf_setcolor -- Sets fill and stroke color

Description

void pdf_setcolor ( int pdf object, string type, string colorspace, float c1 [, float c2 [, float c3 [, float c4]]])

Set the current color space and color. The parameter type can be "fill", "stroke", or "both" to specify that the color is set for filling, stroking or both filling and stroking. The parameter colorspace can be gray, rgb, cmyk, spot or pattern. The parameters c1, c2, c3 and c4 represent the color components for the color space specified by colorspace. Except as otherwise noted, the color components are floating-point values that range from 0 to 1.

For gray only c1 is used.

For rgb parameters c1, c2, and c3 specify the red, green and blue values respectively.

// Set fill and stroke colors to white.
pdf_setcolor($pdf, "both", "rgb", 1, 1, 1);

For cmyk, parameters c1, c2, c3, and c4 are the cyan, magenta, yellow and black values, respectively.

// Set fill and stroke colors to white.
pdf_setcolor($pdf, "both", "cmyk", 0, 0, 0, 1);

For spot, c1 should be a spot color handles returned by pdf_makespotcolor() and c2 is a tint value between 0 and 1.

For pattern, c1 should be a pattern handle returned by pdf_begin_pattern().

pdf_setdash

(PHP 3>= 3.0.6, PHP 4 )

pdf_setdash -- Sets dash pattern

Popis

void pdf_setdash ( int pdf document, double white, double black)

Funkce pdf_setdash() function sets the dash pattern white white points and black black points. If both are 0 a solid line is set.

pdf_setflat

(PHP 3>= 3.0.6, PHP 4 )

pdf_setflat -- Sets flatness

Popis

void pdf_setflat ( int pdf document, double value)

Funkce pdf_setflat() function sets the flatness to a value between 0 and 100.

pdf_setfont

(PHP 4 >= 4.0.5)

pdf_setfont -- Set the current font

Funkce pdf_translate() function sets the origin of coordinate system to the point (x-coor, y-coor) relativ the current origin. The following example draws a line from (0, 0) to (200, 200) relative to the initial coordinate system. You have to set the current point after pdf_translate() and before you start drawing more objects.

Příklad 1. Translation

<?php pdf_moveto($pdf, 0, 0); pdf_lineto($pdf, 100, 100); pdf_stroke($pdf); pdf_translate($pdf, 100, 100); pdf_moveto($pdf, 0, 0); pdf_lineto($pdf, 100, 100); pdf_stroke($pdf); ?>

LXXVII. Funkce pro práci s Verisign Payflow Pro

Tato extenze umožňuje zpracovávat kreditní karty a provádět jiné finanční transakce pomocí Verisign Payment Services (dříve Signio, http://www.verisign.com/products/payflow/pro/index.html).

Tyto funkce jsou dostupné pouze pokud bylo PHP zkompilováno s --with-pfpro[=DIR]. Budete potřebovat SDK pro vaši platformu, který se dá po registraci stáhnout z manažerského rozhraní.

Pokud jste si stáhli správný SDK, zkopírujte následující soubory z lib adresáře této distribuce: pfpro.h do /usr/local/include a libpfpro.so do /usr/local/lib.

Při využívání těchto funkcí můžete vynechat volání pfpro_init() a pfpro_cleanup(), tato extenze to udělá podle potřeby automaticky. Tyto funkce jsou ale přesto dostupné pro případ, že byste potřebovali zpracovávat velké množství transakcí a vyžadovali naprostou kontrolu nad touto knihovnou. Mezi pfpro_init() a pfpro_cleanup() můžete provést libovolné množství transakcí.

Tyto funkce byly přidány v PHP 4.0.2.

Poznámka: Tyto funkce poskytují pouze spojení s Verisign Payment Services. Kompletní detaily vyžadovaných parametrů viz Payflow Pro Developer's Guide.

Obsah
pfpro_cleanup -- Zavřít Payflow Pro knihovnu
pfpro_init -- Inicializovat Payflow Pro knihovnu
pfpro_process_raw -- Zpracovat raw transakci s Payflow Pro
pfpro_process -- Zpracovat transakci s Payflow Pro
pfpro_version -- Vrátit verzi Payflow Pro knihovny

První argument je v tomto případě řetězec obsahující raw požadavek na transakci. Všechny ostatní argumenty jsou stejné jako u pfpro_process(). Návratová hodnota je řetězec obsahující raw odpověď.

Poznámka: Kompletní detaily vyžadovaných parametrů a pravidel kódování viz Payflow Pro Developer's Guide. Dobře vám radíme, používejte radši pfpro_process().

Příklad 1. Ukázka Payflow Pro raw

<?php

pfpro_init();

$response = pfpro_process("USER=mylogin&PWD[5]=m&ndy&TRXTYPE=S&TENDER=C&AMT=1.50&ACCT=4111111111111111&EXPDATE=0904");

if (!$response) {
  die("Nepodařilo se spojit s Verisign.\n");
}

echo "Raw odpověď Verisignu byla ".$response;

pfpro_cleanup();

?>

pfpro_process

(PHP 4 >= 4.0.2)

pfpro_process -- Zpracovat transakci s Payflow Pro

Popis

array pfpro_process ( array parameters [, string address [, int port [, int timeout [, string proxy address [, int proxy port [, string proxy logon [, string proxy password]]]]]]])

Vrací asociativní pole obsahující odpověď.

pfpro_process() zpracuje transakci s Payflow Pro. První argument je asociativní pole obsahující klíče a hodnoty, které se zakódují a odešlou zpracovateli.

Druhý argument je volitelný a určuje serveer, ke kterému se připojit. Default je "test.signio.com", takže pokud chcete zpracovávat skutečné transakce, budete chtít tento argument nastavit na "connect.signio.com".

Třetí argument určuje port, ke kterému se připojit. Default je 443, standardní SSL port.

Čtvrtý argument určuje v sekundách, jaký časový limit se má použít. Default je 30 sekund. Tento časový limit vstupuje v platnost v okamžiku spojení se zpracovatelem, a tak by váš skript mohl potenciálně běžet velmi dlouhou dobu, pokud by nastaly problémy s DNS nebo sítí.

Pátý argument určuje hostname vaší případné SSL proxy. Šestý argument specifikuje port.

Sedmý a osmý argument určují přihlašovací jméno a heslo na tuto proxy.

Tato funkce vrací asociativní pole klíčů a hodnot odpovědi.

Poznámka: Kompletní detaily vyžadovaných parametrů viz Payflow Pro Developer's Guide.

Příklad 1. Ukázka Payflow Pro

<?php

pfpro_init();

$transaction = array(USER	=> 'login',
		     PWD	=> 'heslo',
		     TRXTYPE	=> 'S',
		     TENDER	=> 'C',
		     AMT	=> 1.50,
		     ACCT	=> '4111111111111111',
		     EXPDATE	=> '0904'
		     );

$response = pfpro_process($transaction);

if (!$response) {
  die("Nepodařilo se spojit s Verisign.\n");
}

echo "Response kód Verisignu byl ".$response[RESULT];
echo ", což znamená: ".$response[RESPMSG]."\n";

echo "\nPožadavek na transakci: ";
print_r($transaction);

echo "\nOdpověď: ";
print_r($response);

pfpro_cleanup();

?>

pfpro_version

(PHP 4 >= 4.0.2)

pfpro_version -- Vrátit verzi Payflow Pro knihovny

Popis

string pfpro_version ( void)

pfpro_version() vrací řetězec obsahující verzi Payflow Pro knihovny. V čase psaní tohoto manuálu to bylo L211.

LXXVIII. PHP volby & informace

Obsah
assert_options -- Nastavit/získat různé příznaky výroků
assert -- Ověřit, jestli je výrok neplatný
dl -- Načíst extenzi PHP za běhu
extension_loaded -- zjistit, jestli je extenze načtená
get_cfg_var -- Získat hodnotu volby z konfigurace PHP
get_current_user -- Získat jméno vlastníka současného PHP skriptu
get_defined_constants -- Returns an associative array with the names of all the constants and their values
get_extension_funcs -- Vrátit pole jmen funkcí určitého modulu
get_included_files -- Vrátit pole jmen všech souborů, které byly ve skriptu načteny pomocí include_once()
get_loaded_extensions -- Vrátit pole se jmény všech zkompilovaných a načtených modulů (extenzí)
get_magic_quotes_gpc -- Získat současné aktivní nastavení magic_quotes_gpc
get_magic_quotes_runtime -- Vrátit současné aktivní nastavení magic_quotes_runtime
get_required_files -- Vrátit pole jmen všech souborů, které byly v určitém skriptu načteny pomocí require_once()
getenv -- Získat hodnotu systémové proměnné
getlastmod -- Získat čas poslení modifikace skriptu
getmygid -- Get PHP script owner's GID
getmyinode -- Získat inode současného skriptu
getmypid -- Získat process ID PHP
getmyuid -- Získat UID majitele PHP skriptu
getrusage -- Získat informace o současném využití zdrojů
ini_alter -- Změnit hodnotu konfigurační volby
ini_get_all -- Gets all configuration options
ini_get -- Získat hodnotu konfigurační volby
ini_restore -- Obnovit původní hodnotu konfigurační volby
ini_set -- Změnit hodnotu konfigurační volby
php_logo_guid -- Get the logo guid
php_sapi_name -- Vrátit typ rozhraní mezi web serverem a PHP Returns the type of interface between web server and PHP
php_uname -- Vrátit informaci o operačním systému, na kterém bylo PHP zkompilováno
phpcredits -- Vytisknout credits pro PHP
phpinfo -- Vytisknout spoustu informací o PHP
phpversion -- Získat současnou verzi PHP
putenv -- Nastavit hodnotu systémové proměnné
set_magic_quotes_runtime -- Nastavit současnou aktivní hodnotu magic_quotes_runtime
set_time_limit -- Omezit maximální dobu průběhu skriptu
version_compare -- Compares two "PHP-standardized" version number strings
zend_logo_guid -- Získat zend guid
zend_version -- Gets the version of the current Zend engine

assert_options

(PHP 4 )

assert_options -- Nastavit/získat různé příznaky výroků

Popis

mixed assert_options ( int what [, mixed value])

S použitím funkce assert_options() můžete nastavit různé řídící volby funkce assert(), nebo jen získat jejich současné nastavení.

Tabulka 1. Volby výroků

volba	ini parametr	výchozí hodnota	popis
ASSERT_ACTIVE	assert.active	1	zapne assert() vyhodnocování
ASSERT_WARNING	assert.warning	1	vytvoří PHP varování pro každý selhavší výrok
ASSERT_BAIL	assert.bail	0	ukončí provádění skiptu, pokud výrok selže
ASSERT_QUIET_EVAL	assert.quiet_eval	0	vypne error_reporting během vyhodnocování výrazů výroků
ASSERT_CALLBACK	assert_callback	(`NULL`)	uživatelská funkce, která se zavolá pro každý selhavší výrok

assert_options() vrací původní nastavení volby, nebo FALSE při chybě.

assert

(PHP 4 )

assert -- Ověřit, jestli je výrok neplatný

Popis

int assert ( string|bool assertion)

assert() ověří předanou assertion a provede příslušnou akci, pokud je výsledek FALSE.

Pokud je předaná assertion řetězec, vyhodnotí se funkcí assert() jako PHP kód. Výhody řetězcové assertion jsou menší režie, když je kontrola výroků vypnutá, a zprávy obsahující assertion výraz, když výrok selže.

Kontrola výroků by se měla používat jen pro odlaďování skriptů. Můžete je použít na kontrolu podmínek, které by měly být vždycky TRUE, a které jinak indikují nějaké chyby v programování, nebo na kontrolu existence určitých vlastností, jako jsou funkce obsažené v extenzích, nebo určité systémové limity a vlastnosti.

Výroky by se neměly používat pro běžné operace jako kontrola vstupních parametrů. Jako základní pravidlo platí, že váž kód by měl fungovat správně, pokud není kontrola výroků aktivována.

Chování funkce assert() lze konfigurovat skrze assert_options() nebo .ini direktivy popsané na manuálové stránce této funkce.

dl

(PHP 3, PHP 4 )

dl -- Načíst extenzi PHP za běhu

Popis

Viz také getmyuid(), getmypid(), getmyinode(), a getlastmod().

get_defined_constants

(PHP 4 >= 4.1.0)

get_defined_constants -- Returns an associative array with the names of all the constants and their values

Description

array get_defined_constants ( void)

This function returns the names and values of all the constants currently defined. This includes those created by extensions as well as those created with the define() function.

For example the line below

print_r (get_defined_constants());

will print a list like:

Array
(
    [E_ERROR] => 1
    [E_WARNING] => 2
    [E_PARSE] => 4
    [E_NOTICE] => 8
    [E_CORE_ERROR] => 16
    [E_CORE_WARNING] => 32
    [E_COMPILE_ERROR] => 64
    [E_COMPILE_WARNING] => 128
    [E_USER_ERROR] => 256
    [E_USER_WARNING] => 512
    [E_USER_NOTICE] => 1024
    [E_ALL] => 2047
    [TRUE] => 1
)

get_extension_funcs

(PHP 4 )

get_extension_funcs -- Vrátit pole jmen funkcí určitého modulu

Popis

array get_extension_funcs ( string module_name)

Tato funkce vrací jména všech funkcí definovaných v modulu určeném argumentem module_name.

Například následující řádky

print_r (get_extension_funcs ("xml"));
print_r (get_extension_funcs ("gd"));

vytisknou seznam všech funkcí v modulech xml a gd.

Viz také: get_loaded_extensions()

get_included_files

(PHP 4 )

get_included_files -- Vrátit pole jmen všech souborů, které byly ve skriptu načteny pomocí include_once()

Popis

array get_included_files ( void)

Tato funkce vrátí asociativní pole jmen všech souborů, které byly načteny do skriptu pomocí include_once(). Indexy tohoto pole jsou názvy souborů použitých v include_once() bez přípony ".php".

Poznámka: Od verze PHP 4.0.1pl2 tato funkce předpokládá, že soubory v include_once končí příponou ".php", jiné přípony nefungují.

Viz také: require_once(), include_once(), get_required_files()

get_loaded_extensions

(PHP 4 )

get_loaded_extensions -- Vrátit pole se jmény všech zkompilovaných a načtených modulů (extenzí)

Popis

array get_loaded_extensions ( void)

Tato funkce vrací jména všech modulů (extenzí) zkompilovaných a načtených do PHP interpretru.

Například následující řádek

print_r (get_loaded_extensions());

vypíše seznam podobný tomuto:

Array
(
    [0] => xml
    [1] => wddx
    [2] => standard
	  [3] => session
	  [4] => posix
	  [5] => pgsql
	  [6] => pcre
	  [7] => gd
	  [8] => ftp
	  [9] => db
	  [10] => Calendar
	  [11] => bcmath
)

Následující příklad

Příklad 1. Tisk require()ovaných a include()ovaných souborů

<?php require_once ("local.php"); require_once ("../inc/global.php"); for ($i=1; $i<5; $i++) include "util".$i."php"; echo "Required_once files\n"; print_r (get_required_files()); echo "Included_once files\n"; print_r (get_included_files()); ?>
vygeneruje následující výstup:

Required_once files
Array
(
  [local] => local.php
  [../inc/global] => /full/path/to/inc/global.php
)

Included_once files
Array
(
    [util1] => util1.php
    [util2] => util2.php
    [util3] => util3.php
    [util4] => util4.php
)

Poznámka: Od verze PHP 4.0.1pl2 tato funkce předpokládá, že soubory v required_once končí příponou ".php", jiné přípony nefungují.

Viz také: require_once(), include_once(), get_included_files()

getenv

(PHP 3, PHP 4 )

getenv -- Získat hodnotu systémové proměnné

Popis

string getenv ( string varname)

Vrátí hodnotu systémové proměnné varname, nebo FALSE při chybě.

$ip = getenv ("REMOTE_ADDR"); // získá IP adresu uživatele

Seznam všech systémových proměnných si můžete prohlédnout použitím phpinfo(). Význam mnoha z nich najdete v CGI specifikaci, zvláště na stránce o systémových proměnných.

Poznámka: Tato funkce nefunguje v ISAPI módu.

getlastmod

(PHP 3, PHP 4 )

getlastmod -- Získat čas poslení modifikace skriptu

Popis

int getlastmod ( void)

Vrátí čas poslení modifikace současné stránky. Návratová hodnota je Unixový timestamp, vhodný jako vstup pro date(). Při chybě vrací FALSE.

Příklad 1. getlastmod() příklad

// outputs e.g. 'Last modified: March 04 1998 20:43:59.' echo "Last modified: ".date ("F d Y H:i:s.", getlastmod());

See alse date(), getmyuid(), get_current_user(), getmyinode(), and getmypid().

getmygid

(PHP 4 >= 4.1.0)

getmygid -- Get PHP script owner's GID

Description

int getmygid ( void)

Returns the group ID of the current script, or FALSE on error.

getmyinode

(PHP 3, PHP 4 )

getmyinode -- Získat inode současného skriptu

Popis

int getmyinode ( void)

Vrátí inode současného skriptu, nebo FALSE při chybě.

Viz také getmyuid(), get_current_user(), getmypid(), and getlastmod().

Poznámka: Tato funkce není podporována na Windows systémech.

getmypid

(PHP 3, PHP 4 )

getmypid -- Získat process ID PHP

Popis

int getmypid ( void)

Vrátí process ID současného PHP procesu, nebo FALSE při chybě.

string ini_alter ( string varname, string newvalue)

Změní hodnotu konfigurační volby, vrátí FALSE při selhání, a předchozí hodnotu konfigurační volby při úspěchu.

Poznámka: Toto je alias k ini_set()

Viz také ini_get(), ini_restore(), ini_set()

ini_get_all

(PHP 4 >= 4.2.0)

ini_get_all -- Gets all configuration options

string php_logo_guid ( void)

Poznámka: Tato funkcionalita byla přidána v PHP 4 Beta 4.

...
phpcredits(CREDITS_GENERAL);
...

A pokud chcete vytisknout užší kruh vývojářů a dokumentační skupinu na samostatné stránce, použijte:

<?php
phpcredits(CREDITS_GROUP + CREDITS_DOCS + CREDITS_FULLPAGE);
?>

A pokud chcete vložit všechny credits do vlastní stránky, pomůže vám následující kód:

<html>
 <head>
  <title>Má stránka s credits</title>
 </head>
 <body>
  <?php
	// váš vlastní kód
	phpcredits(CREDITS_ALL + CREDITS_FULLPAGE);
	// další kód
	?>
 </body>
</html>

Tabulka 1. Předdefinované phpcredits() příznaky

název	popis
CREDITS_ALL	Všechny credits, ekvivalentní k: CREDITS_DOCS + CREDITS_GENERAL + CREDITS_GROUP + CREDITS_MODULES + CREDITS_FULLPAGE. Vygeneruje kompletní samostatnou HTML stránku s příslušnými tagy.
CREDITS_DOCS	Credits dokumentačního týmu
CREDITS_FULLPAGE	Obvykle se používá v kombinaci s jinými příznaky. Indikuje, že se má vytisknout kompletní samostatná HTML stránka, včetně informací indikovaných jinými příznaky.
CREDITS_GENERAL	Všeobecné credits: Design a koncept jazyka, autoři PHP 4.0 a SAPI modul.
CREDITS_GROUP	Seznam užšího kruhu vývojářů
CREDITS_MODULES	Seznam rozšiřujících modulů (extenzí) PHP a jejich autorů
CREDITS_SAPI	Seznam server API modulů PHP a jejich autorů

Viz také phpinfo(), phpversion(), php_logo_guid().

phpinfo

(PHP 3, PHP 4 )

phpinfo -- Vytisknout spoustu informací o PHP

Popis

int phpinfo ( [int what])

Vytiskne velké množství informací o současném stavu PHP. To zahrnuje informace o kompilačních volbách a extenzích, verzi PHP, informaci o serveru a systémů (pokud je PHP zkompilováno jako modul), PHP prostředí, verzi OS, cesty, hlavní a lokální hodnoty konfiguračních voleb, HTTP hlavičky, a PHP licenci.

Výstup se dá upravit předáním jednou nebo více z následujících hodnot uložených ve volitelném argumentu what.

INFO_GENERAL
INFO_CREDITS
INFO_CONFIGURATION
INFO_MODULES
INFO_ENVIRONMENT
INFO_VARIABLES
INFO_LICENSE
INFO_ALL

set_time_limit() při svém zavolání restartuje čítač času od nuly. Jinými slovy, pokud je limit standardních šé sekund a po 25 sekundách provádění skriptu dojde k volání set_time_limit(20), tento skript poběží celkem 45 sekund předtím, než skončí na časovém limitu.

Všimněte si, že set_time_limit() nemá žádný účinek, když PHP běží v bezpečném módu. Obejít to lz jedine vypnutím bezpečného módu nebo změnou časového limitu v konfiguračním souboru.

version_compare

(PHP 4 >= 4.1.0)

version_compare -- Compares two "PHP-standardized" version number strings

Description

int version_compare ( string version1, string version2 [, string operator])

version_compare() compares two "PHP-standardized" version number strings. This is useful if you would like to write programs working only on some versions of PHP.

version_compare() returns -1 if the first version is lower than the second, 0 if they are equal, and +1 if the second is lower.

If you specify the third optional operator argument, you can test for a particular relationship. The possible operators are: <, lt, <=, le, >, gt, >=, ge, ==, =, eq, !=, <>, ne respectively. Using this argument, the function will return 1 if the relationship is the one specified by the operator, 0 otherwise.

Příklad 1. version_compare() Example

// prints -1 echo version_compare("4.0.4", "4.0.6"); // these all print 1 echo version_compare("4.0.4", "4.0.6", "<"); echo version_compare("4.0.6", "4.0.6", "eq");

zend_logo_guid

(PHP 4 )

zend_logo_guid -- Získat zend guid

Popis

string zend_logo_guid ( void)

Poznámka: Tato funkcionalita byla přidána v PHP 4 Beta 4.

zend_version

(PHP 4 )

zend_version -- Gets the version of the current Zend engine

Description

string zend_version ( void)

Returns a string containing the version of the currently running PHP parser.

Příklad 1. zend_version() Example

// prints e.g. 'Zend engine version: 1.0.4' echo "Zend engine version: " . zend_version();

LXXIX. POSIX functions

This module contains an interface to those functions defined in the IEEE 1003.1 (POSIX.1) standards document which are not accessible through other means. POSIX.1 for example defined the open(), read(), write() and close() functions, too, which traditionally have been part of PHP 3 for a long time. Some more system specific functions have not been available before, though, and this module tries to remedy this by providing easy access to these functions.

Varování

Sensitive data can be retrieved with the POSIX functions, e.g. posix_getpwnam() and friends. None of the POSIX function perform any kind of access checking when safe mode is enabled. It's therefore strongly advised to disable the POSIX extension at all (use --disable-posix in your configure line) if you're operating in such an environment.

Poznámka: The POSIX extension is not available on the Windows platform.

Obsah
posix_ctermid -- Get path name of controlling terminal
posix_getcwd -- Pathname of current directory
posix_getegid -- Return the effective group ID of the current process
posix_geteuid -- Return the effective user ID of the current process
posix_getgid -- Return the real group ID of the current process
posix_getgrgid -- Return info about a group by group id
posix_getgrnam -- Return info about a group by name
posix_getgroups -- Return the group set of the current process
posix_getlogin -- Return login name
posix_getpgid -- Get process group id for job control
posix_getpgrp -- Return the current process group identifier
posix_getpid -- Return the current process identifier
posix_getppid -- Return the parent process identifier
posix_getpwnam -- Return info about a user by username
posix_getpwuid -- Return info about a user by user id
posix_getrlimit -- Return info about system ressource limits
posix_getsid -- Get the current sid of the process
posix_getuid -- Return the real user ID of the current process
posix_isatty -- Determine if a file descriptor is an interactive terminal
posix_kill -- Send a signal to a process
posix_mkfifo -- Create a fifo special file (a named pipe)
posix_setegid -- Set the effective GID of the current process
posix_seteuid -- Set the effective UID of the current process
posix_setgid -- Set the GID of the current process
posix_setpgid -- set process group id for job control
posix_setsid -- Make the current process a session leader
posix_setuid -- Set the UID of the current process
posix_times -- Get process times
posix_ttyname -- Determine terminal device name
posix_uname -- Get system name

posix_getsid

(PHP 3>= 3.0.10, PHP 4 )

posix_getsid -- Get the current sid of the process

Description

int posix_getsid ( int pid)

bool posix_kill ( int pid, int sig)

Send the signal sig to the process with the process identifier pid. Returns FALSE, if unable to send the signal, TRUE otherwise.

See also the kill(2) manual page of your POSIX system, which contains additional information about negative process identifiers, the special pid 0, the special pid -1, and the signal number 0.

posix_mkfifo

(PHP 3>= 3.0.13, PHP 4 )

posix_mkfifo -- Create a fifo special file (a named pipe)

Description

bool posix_mkfifo ( string pathname, int mode)

posix_mkfifo() creates a special FIFO file which exists in the file system and acts as a bidirectional communication endpoint for processes.

The second parameter mode has to be given in octal notation (e.g. 0644). The permission of the newly created FIFO also depends on the setting of the current umask(). The permissions of the created file are (mode & ~umask).

Poznámka: Pokud je zapnut bezpečný režim (safe-mode), PHP kontroluje, zda adresář, ve kterém pracujete, má stejné UID jako spuštěný skript.

bool posix_setuid ( int uid)

Set the real user ID of the current process. This is a privileged function and you need appropriate privileges (usually root) on your system to be able to perform this function.

Returns TRUE on success, FALSE otherwise. See also posix_setgid().

posix_times

(PHP 3>= 3.0.13, PHP 4 )

posix_times -- Get process times

Description

array posix_times ( void)

Returns a hash of strings with information about the current process CPU usage. The indices of the hash are

ticks - the number of clock ticks that have elapsed since reboot.
utime - user time used by the current process.
stime - system time used by the current process.
cutime - user time used by current process and children.
cstime - system time used by current process and children.

posix_ttyname

(PHP 3>= 3.0.13, PHP 4 )

posix_ttyname -- Determine terminal device name

Description

string posix_ttyname ( int fd)

Needs to be written.

posix_uname

(PHP 3>= 3.0.10, PHP 4 )

posix_uname -- Get system name

Description

array posix_uname ( void)

Returns a hash of strings with information about the system. The indices of the hash are

sysname - operating system name (e.g. Linux)
nodename - system name (e.g. valiant)
release - operating system release (e.g. 2.2.10)
version - operating system version (e.g. #4 Tue Jul 20 17:01:36 MEST 1999)
machine - system architecture (e.g. i586)
domainname - DNS domainname (e.g. php.net)

domainname is a GNU extension and not part of POSIX.1, so this field is only available on GNU systems or when using the GNU libc.

Posix requires that you must not make any assumptions about the format of the values, e.g. you cannot rely on three digit version numbers or anything else returned by this function.

LXXX. PostgreSQL functions

Postgres, developed originally in the UC Berkeley Computer Science Department, pioneered many of the object-relational concepts now becoming available in some commercial databases. It provides SQL92/SQL99 language support, transaction integrity and type extensibility. PostgreSQL is an open source descendant of this original Berkeley code.

PostgreSQL database is Open Source product and available without cost. To use PostgreSQL support, you need PostgreSQL 6.5 or later. PostgreSQL 7.0 or later to enable all PostgreSQL module feature. PostgreSQL supports many character encoding including multibyte character encoding. The current version and more information about PostgreSQL is available at http://www.postgresql.org/.

In order to enable PostgreSQL support, --with-pgsql[=DIR] is required when you compile PHP. If shared object module is available, PostgreSQL module may be loaded using extension directive in php.ini or dl() function. Supported ini directives are described in php.ini-dist which comes with source distribution.

Varování

Using the PostgreSQL module with PHP 4.0.6 is not recommended due to a bug in the notice message handling code. Use 4.1.0 or later.

Varování

PostgreSQL function names will be changed in 4.2.0 release to confirm to current coding standards. Most of new names will have additional underscores, e.g. pg_lo_open(). Some functions are renamed to different name for consistency. e.g. pg_exec() to pg_query(). Older names can be used in 4.2.0 and a few releases from 4.2.0, but they may be deleted in the future.

Tabulka 1. Function names changed

Old name	New name
pg_exec()	pg_query()
pg_getlastoid()	pg_last_oid()
pg_cmdtuples()	pg_affected_rows()
pg_numrows()	pg_num_rows()
pg_numfields()	pg_num_fields()
pg_fieldname()	pg_field_name()
pg_fieldsize()	pg_field_size()
pg_fieldnum()	pg_field_num()
pg_fieldprtlen()	pg_field_prtlen()
pg_fieldisnull()	pg_field_is_null()
pg_freeresult()	pg_free_result()
pg_result()	pg_fetch_result()
pg_loreadall()	pg_lo_read_all()
pg_locreate()	pg_lo_create()
pg_lounlink()	pg_lo_unlink()
pg_loopen()	pg_lo_open()
pg_loclose()	pg_lo_close()
pg_loread()	pg_lo_read()
pg_lowrite()	pg_lo_write()
pg_loimport()	pg_lo_import()
pg_loexport()	pg_lo_export()

The old pg_connect()/pg_pconnect() syntax will be deprecated to support asynchronous connections in the future. Please use a connection string for pg_connect() and pg_pconnect().

Not all functions are supported by all builds. It depends on your libpq (The PostgreSQL C Client interface) version and how libpq is compiled. If there is missing function, libpq does not support the feature required for the function.

It is also important that you use newer libpq than PostgreSQL Server to be connected. If you use libpq older than PostgreSQL Server expects, you may have problems.

Since version 6.3 (03/02/1998) PostgreSQL uses unix domain sockets by default. TCP port will NOT be opened by default. A table is shown below describing these new connection possibilities. This socket will be found in /tmp/.s.PGSQL.5432. This option can be enabled with the '-i' flag to postmaster and it's meaning is: "listen on TCP/IP sockets as well as Unix domain sockets".

Tabulka 2. Postmaster and PHP

Postmaster	PHP	Status
postmaster &	pg_connect("dbname=MyDbName");	OK
postmaster -i &	pg_connect("dbname=MyDbName");	OK
postmaster &	pg_connect("host=localhost dbname=MyDbName");	Unable to connect to PostgreSQL server: connectDB() failed: Is the postmaster running and accepting TCP/IP (with -i) connection at 'localhost' on port '5432'? in /path/to/file.php on line 20.
postmaster -i &	pg_connect("host=localhost dbname=MyDbName");	OK

A connection to PostgreSQL server can be established with the following value pairs set in the command string: $conn = pg_connect("host=myHost port=myPort tty=myTTY options=myOptions dbname=myDB user=myUser password=myPassword ");

The previous syntax of: $conn = pg_connect ("host", "port", "options", "tty", "dbname") has been deprecated.

Environmental variables affect PostgreSQL server/client behavior. For example, PostgreSQL module will lookup PGHOST environment variable when the hostname is omitted in the connection string. Supported environment variables are different from version to version. Refer to PostgreSQL Programmer's Manual (libpq - Environment Variables) for details.

Make sure you set environment variables for appropriate user. Use $_ENV or getenv() to check which environment variables are available to the current process.

Příklad 1. Setting default parameters

PGHOST=pgsql.example.com
PGPORT=7890
PGDATABASE=web-system
PGUSER=web-user
PGPASSWORD=secret
PGDATESTYLE=ISO
PGTZ=JST
PGCLIENTENCODING=EUC-JP

export PGHOST PGPORT PGDATABASE PGUSER PGPASSWORD PGDATESTYLE PGTZ PGCLIENTENCODING

Starting with PostgreSQL 7.1.0, you can store up to 1GB into a field of type text. In older versions, this was limited to the block size (default was 8KB, maximum was 32KB, defined at compile time)

To use the large object (lo) interface, it is required to enclose large object functions within a transaction block. A transaction block starts with a SQL statement BEGIN and if the transaction was valid ends with COMMIT or END. If the transaction fails the transaction should be closed with ROLLBACK or ABORT.

Příklad 2. Using Large Objects

<?php $database = pg_connect ("dbname=jacarta"); pg_query ($database, "begin"); $oid = pg_lo_create ($database); echo "$oid\n"; $handle = pg_lo_open ($database, $oid, "w"); echo "$handle\n"; pg_lo_write ($handle, "large object data"); pg_lo_close ($handle); pg_query ($database, "commit"); ?>
You should not close the connection to the PostgreSQL server before closing the large object.

Obsah
pg_affected_rows -- Returns number of affected records(tuples)
pg_cancel_query -- Cancel async query
pg_client_encoding -- Get the client encoding
pg_close -- Close a PostgreSQL connection
pg_connect -- Open a PostgreSQL connection
pg_connection_busy -- Get connection is busy or not
pg_connection_reset -- Reset connection (reconnect)
pg_connection_status -- Get connection status
pg_convert -- Convert associative array value into suitable for SQL statement.
pg_copy_from -- Insert records into a table from an array
pg_copy_to -- Copy a table to an array
pg_dbname -- Get the database name
pg_delete -- Delete records.
pg_end_copy -- Sync with PostgreSQL backend
pg_escape_bytea -- Escape binary for bytea type
pg_escape_string -- Escape string for text/char type
pg_fetch_array -- Fetch a row as an array
pg_fetch_object -- Fetch a row as an object
pg_fetch_result -- Returns values from a result resource
pg_fetch_row -- Get a row as an enumerated array
pg_field_is_null -- Test if a field is NULL
pg_field_name -- Returns the name of a field
pg_field_num -- Returns the field number of the named field
pg_field_prtlen -- Returns the printed length
pg_field_size -- Returns the internal storage size of the named field
pg_field_type -- Returns the type name for the corresponding field number
pg_free_result -- Free result memory
pg_get_result -- Get asynchronous query result
pg_host -- Returns the host name associated with the connection
pg_insert -- Insert array into table.
pg_last_error -- Get the last error message string of a connection
pg_last_notice -- Returns the last notice message from PostgreSQL server
pg_last_oid -- Returns the last object's oid
pg_lo_close -- Close a large object
pg_lo_create -- Create a large object
pg_lo_export -- Export a large object to file
pg_lo_import -- Import a large object from file
pg_lo_open -- Open a large object
pg_lo_read_all -- Read a entire large object and send straight to browser
pg_lo_read -- Read a large object
pg_lo_seek -- Seeks position of large object
pg_lo_tell -- Returns current position of large object
pg_lo_unlink -- Delete a large object
pg_lo_write -- Write a large object
pg_metadata -- Get metadata for table.
pg_num_fields -- Returns the number of fields
pg_num_rows -- Returns the number of rows
pg_options -- Get the options associated with the connection
pg_pconnect -- Open a persistent PostgreSQL connection
pg_port -- Return the port number associated with the connection
pg_put_line -- Send a NULL-terminated string to PostgreSQL backend
pg_query -- Execute a query
pg_result_error -- Get error message associated with result
pg_result_status -- Get status of query result
pg_select -- Select records.
pg_send_query -- Send asynchronous query
pg_set_client_encoding -- Set the client encoding
pg_trace -- Enable tracing a PostgreSQL connection
pg_tty -- Return the tty name associated with the connection
pg_untrace -- Disable tracing of a PostgreSQL connection
pg_update -- Update table.

pg_affected_rows

(PHP 4 >= 4.2.0)

pg_affected_rows -- Returns number of affected records(tuples)

Description

int pg_affected_rows ( resource result)

pg_affected_rows() returns the number of tuples (instances/records/rows) affected by INSERT, UPDATE, and DELETE queries executed by pg_query(). If no tuple is affected by this function, it will return 0.

Příklad 1. pg_affected_rows()

<?php $result = pg_query ($conn, "INSERT INTO publisher VALUES ('Author')"); $cmdtuples = pg_affected_rows ($result); echo $cmdtuples . " tuples are affected."; ?>

Poznámka: This function used to be called pg_cmdtuples().

See also pg_query() and pg_num_rows().

pg_cancel_query

(PHP 4 >= 4.2.0)

pg_cancel_query -- Cancel async query

Description

bool pg_cancel_query ( resource connection)

pg_cancel_query() cancel asynchronous query sent by pg_send_query(). You cannot cancel query executed by pg_query().

pg_client_encoding

(PHP 3 CVS only, PHP 4 >= 4.0.3)

pg_client_encoding -- Get the client encoding

Description

string pg_client_encoding ( [resource connection])

pg_client_encoding() returns the client encoding as the string. The returned string should be either : SQL_ASCII, EUC_JP, EUC_CN, EUC_KR, EUC_TW, UNICODE, MULE_INTERNAL, LATINX (X=1...9), KOI8, WIN, ALT, SJIS, BIG5, WIN1250.

Poznámka: This function requires PHP-4.0.3 or higher and PostgreSQL-7.0 or higher. If libpq is compiled without multibyte encoding support, pg_set_client_encoding() always return "SQL_ASCII". Supported encoding depends on PostgreSQL version. Refer to PostgreSQL manual for details to enable multibyte support and encoding supported.

The function used to be called pg_clientencoding().

pg_close

(PHP 3, PHP 4 )

pg_close -- Close a PostgreSQL connection

Description

bool pg_close ( resource connection)

pg_close() closes the non-persistent connection to a PostgreSQL database associated with the given connection resource. Vrací TRUE při úspěchu, FALSE při selhání.

Poznámka: Using pg_close() is not usually necessary, as non-persistent open connections are automatically closed at the end of the script.

pg_connection_status() returns a connection status. Possible statuses are PGSQL_CONNECTION_OK and PGSQL_CONNECTION_BAD.

pg_convert

(PHP 4 CVS only)

pg_convert -- Convert associative array value into suitable for SQL statement.

Description

array pg_convert ( resource connection, string table_name, array assoc_array [, int options])

pg_convert() check and convert assoc_array suitable for SQL statement.

Poznámka: This function is experimental.

Příklad 1. pg_delete

<?php 
    $db = pg_connect ('dbname=foo');
    // This is safe, since $_POST is converted automatically
    $res = pg_delete($db, 'post_log', $_POST);
    if ($res) {
        echo "POST data is deleted: $res\n";
    }
    else {
        echo "User must have sent wrong inputs\n";
    }
?>

Poznámka: This function is experimental.

pg_fetch_array() is an extended version of pg_fetch_row(). In addition to storing the data in the numeric indices (field index) to the result array, it also stores the data in associative indices (field name) by default.

row is row (record) number to be retrieved. First row is 0.

result_type is optional parameter controls how return value is initialized. result_type is a constant and can take the following values: PGSQL_ASSOC, PGSQL_NUM, and PGSQL_BOTH. pg_fetch_array() returns associative array that has field name as key for PGSQL_ASSOC. field index as key with PGSQL_NUM and both field name/index as key with PGSQL_BOTH. Default is PGSQL_BOTH.

Poznámka: result_type was added in PHP 4.0.

pg_fetch_array() is NOT significantly slower than using pg_fetch_row(), while it provides a significant ease of use.

Příklad 1. PostgreSQL fetch array

<?php $conn = pg_pconnect ("dbname=publisher"); if (!$conn) { echo "An error occured.\n"; exit; } $result = pg_query ($conn, "SELECT * FROM authors"); if (!$result) { echo "An error occured.\n"; exit; } $arr = pg_fetch_array ($result, 0, PGSQL_NUM); echo $arr[0] . " <- array\n"; $arr = pg_fetch_array ($result, 1, PGSQL_ASSOC); echo $arr["author"] . " <- array\n"; ?>

Poznámka: From 4.1.0, row became optional. Calling pg_fetch_array() will increment internal row counter by 1.

pg_fetch_object

(PHP 3>= 3.0.1, PHP 4 )

pg_fetch_object -- Fetch a row as an object

Description

object pg_fetch_object ( resource result, int row [, int result_type])

pg_fetch_object() returns an object with properties that correspond to the fetched row. It returns FALSE if there are no more rows or error.

pg_fetch_object() is similar to pg_fetch_array(), with one difference - an object is returned, instead of an array. Indirectly, that means that you can only access the data by the field names, and not by their offsets (numbers are illegal property names).

row is row (record) number to be retrieved. First row is 0.

Speed-wise, the function is identical to pg_fetch_array(), and almost as quick as pg_fetch_row() (the difference is insignificant).

Poznámka: From 4.3.0, result_type is default to PGSQL_ASSOC while older versions' default was PGSQL_BOTH. There is no use for numeric property, since numeric property name is invalid in PHP.

result_type may be deleted in future versions.

Příklad 1. Postgres fetch object

<?php $database = "verlag"; $db_conn = pg_connect ("host=localhost port=5432 dbname=$database"); if (!$db_conn): ?> <H1>Failed connecting to postgres database <?php echo $database ?></H1> <?php exit; endif; $qu = pg_query ($db_conn, "SELECT * FROM verlag ORDER BY autor"); $row = 0; // postgres needs a row counter other dbs might not while ($data = pg_fetch_object ($qu, $row)) { echo $data->autor." ("; echo $data->jahr ."): "; echo $data->titel."<BR>"; $row++; } ?> <PRE> <?php $fields[] = Array ("autor", "Author"); $fields[] = Array ("jahr", " Year"); $fields[] = Array ("titel", " Title"); $row= 0; // postgres needs a row counter other dbs might not while ($data = pg_fetch_object ($qu, $row)) { echo "----------\n"; reset ($fields); while (list (,$item) = each ($fields)): echo $item[1].": ".$data->$item[0]."\n"; endwhile; $row++; } echo "----------\n"; ?> </PRE> <?php pg_free_result ($qu); pg_close ($db_conn); ?>

Poznámka: From 4.1.0, row became optional. Calling pg_fetch_object() will increment internal row counter counter by 1.

pg_fetch_result

(PHP 4 >= 4.2.0)

pg_fetch_result -- Returns values from a result resource

Description

mixed pg_fetch_result ( resource result, int row, mixed field)

pg_fetch_result() returns values from a result resource returned by pg_query(). row is integer. field is field name(string) or field index (integer). The row and field specify what cell in the table of results to return. Row numbering starts from 0. Instead of naming the field, you may use the field index as an unquoted number. Field indices start from 0.

PostgreSQL has many built in types and only the basic ones are directly supported here. All forms of integer, boolean and void types are returned as integer values. All forms of float, and real types are returned as float values. All other types, including arrays are returned as strings formatted in the same default PostgreSQL manner that you would see in the psql program.

pg_fetch_row

(PHP 3>= 3.0.1, PHP 4 )

pg_fetch_row -- Get a row as an enumerated array

Description

array pg_fetch_row ( resource result, int row)

pg_fetch_row() fetches one row of data from the result associated with the specified result resource. The row (record) is returned as an array. Each result column is stored in an array offset, starting at offset 0.

It returns an array that corresponds to the fetched row, or FALSE if there are no more rows.

Příklad 1. Postgres fetch row

<?php $conn = pg_pconnect ("dbname=publisher"); if (!$conn) { echo "An error occured.\n"; exit; } $result = pg_query ($conn, "SELECT * FROM authors"); if (!$result) { echo "An error occured.\n"; exit; } $num = pg_num_rows($result); for ($i=0; $i < $num; $i++) { $r = pg_fetch_row($result, $i); for ($j=0; $j < count($r); $j++) { echo "$r[$j] "; } echo "<BR>"; } ?>

Poznámka: From 4.1.0, row became optional. Calling pg_fetch_row() will increment internal row counter by 1.

pg_field_is_null

(PHP 4 >= 4.2.0)

pg_field_is_null -- Test if a field is NULL

Description

int pg_field_is_null ( resource result, int row, mixed field)

pg_field_is_null() test if a field is NULL or not. It returns 1 if the field in the given row is NULL. It returns 0 if the field in the given row is NOT NULL. Field can be specified as column index (number) or fieldname (string). Row numbering starts at 0.

Poznámka: This function used to be called pg_fieldisnull().

pg_field_name

(PHP 4 >= 4.2.0)

pg_field_name -- Returns the name of a field

Description

string pg_field_name ( resource result, int field_number)

pg_field_name() returns the name of the field occupying the given field_number in the given PostgreSQL result resource. Field numbering starts from 0.

Poznámka: This function used to be called pg_fieldname().

pg_field_num

(PHP 4 >= 4.2.0)

pg_field_num -- Returns the field number of the named field

Description

int pg_field_num ( resource result, string field_name)

pg_field_num() will return the number of the column (field) slot that corresponds to the field_name in the given PostgreSQL result resource. Field numbering starts at 0. This function will return -1 on error.

Poznámka: This function used to be called pg_fieldnum().

pg_field_prtlen

(PHP 4 >= 4.2.0)

pg_field_prtlen -- Returns the printed length

Description

int pg_field_prtlen ( resource result, int row_number, string field_name)

pg_field_prtlen() returns the actual printed length (number of characters) of a specific value in a PostgreSQL result. Row numbering starts at 0. This function will return -1 on an error.

Poznámka: This function used to be called pg_field_prtlen().

pg_field_size

(PHP 4 >= 4.2.0)

pg_field_size -- Returns the internal storage size of the named field

Description

int pg_field_size ( resource result, int field_number)

pg_field_size() returns the internal storage size (in bytes) of the field number in the given PostgreSQL result. Field numbering starts at 0. A field size of -1 indicates a variable length field. This function will return FALSE on error.

Poznámka: This function used to be called pg_fieldsize().

See also pg_field_len() and pg_field_type().

pg_field_type

(PHP 4 >= 4.2.0)

pg_field_type -- Returns the type name for the corresponding field number

Description

string pg_field_type ( resource result, int field_number)

pg_field_type() returns a string containing the type name of the given field_number in the given PostgreSQL result resource. Field numbering starts at 0.

Poznámka: This function used to be called pg_fieldtype().

See also pg_field_len() and pg_field_name().

pg_free_result

(PHP 4 >= 4.2.0)

pg_free_result -- Free result memory

Description

bool pg_free_result ( resource result)

pg_free_result() only needs to be called if you are worried about using too much memory while your script is running. All result memory will automatically be freed when the script is finished. But, if you are sure you are not going to need the result data anymore in a script, you may call pg_free_result() with the result resource as an argument and the associated result memory will be freed. It returns true on success and false if an error occurs.

Poznámka: This function used to be called pg_freeresult().

pg_get_result

(PHP 4 >= 4.2.0)

pg_get_result -- Get asynchronous query result

Description

resource pg_get_result ( [resource connection])

pg_get_result() get result resource from async query executed by pg_send_query(). pg_send_query() can send multiple queries to PostgreSQL server and pg_get_result() is used to get query result one by one. It returns result resource. If there is no more results, it returns FALSE.

pg_host

(PHP 3, PHP 4 )

pg_host -- Returns the host name associated with the connection

Description

string pg_host ( resource connection)

pg_host() returns the host name of the given PostgreSQL connection resource is connected to.

See also pg_connect() and pg_pconnect().

pg_insert

(PHP 4 CVS only)

pg_insert -- Insert array into table.

Description

bool pg_insert ( resource connection, string table_name, array assoc_array [, int options])

pg_insert() inserts assoc_array which has field=>value into table specified as table_name. If options is specified, pg_convert() is applied to assoc_array with specified option.

Příklad 1. pg_insert

<?php 
    $db = pg_connect ('dbname=foo');
    // This is safe, since $_POST is converted autotmatically
    $res = pg_insert($db, 'post_log', $_POST);
    if ($res) {
        echo "POST data is succesfully logged\n";
    }
    else {
        echo "User must have sent wrong inputs\n";
    }
?>

Poznámka: This function is experimental.

See also pg_convert()

pg_last_error

(PHP 4 >= 4.2.0)

pg_last_error -- Get the last error message string of a connection

Description

string pg_last_error ( resource connection)

pg_last_error() returns the last error message for given connection.

Error messages may be overwritten by internal PostgreSQL(libpq) function calls. It may not return appropriate error message, if multiple errors are occured inside a PostgreSQL module function.

Use pg_result_error(), pg_result_status() and pg_connection_status() for better error handling.

Poznámka: This function used to be called pg_errormessage().

pg_last_notice

(PHP 4 >= 4.0.6)

pg_last_notice -- Returns the last notice message from PostgreSQL server

Description

string pg_last_notice ( resource connection)

pg_last_notice() returns the last notice message from the PostgreSQL server specified by connection. The PostgreSQL server sends notice messages in several cases, e.g. if the transactions can't be continued. With pg_last_notice(), you can avoid issuing useless queries, by checking whether the notice is related to the transaction or not.

Varování

This function is EXPERIMENTAL and it is not fully implemented yet. pg_last_notice() was added in PHP 4.0.6. However, PHP 4.0.6 has problem with notice message handling. Use of the PostgreSQL module with PHP 4.0.6 is not recommended even if you are not using pg_last_notice().

int pg_lo_import ( [resource connection, string pathname])

In versions before PHP 4.2.0 the syntax of this function was different, see the following definition:

int pg_lo_import ( [resource connection, string pathname])

The pathname argument specifies the pathname of the file to be imported as a large object. It returns FALSE if an error occurred, oid of the just created large object otherwise.

To use the large object (lo) interface, it is necessary to enclose it within a transaction block.

Poznámka: Pokud je zapnut bezpečný režim (safe-mode), PHP kontroluje, zda soubory/adresáře, se kterými pracujete, mají stejné UID jako spuštěný skript.

Poznámka: This function used to be called pg_loimport().

See also pg_lo_export() and pg_lo_open().

pg_lo_open

(PHP 4 >= 4.2.0)

pg_lo_open -- Open a large object

Description

resource pg_lo_open ( resource connection, int oid, string mode)

pg_lo_open() open a Large Object and returns large object resource. The resource encapsulates information about the connection. oid specifies a valid large object oid and mode can be either "r", "w", or "rw". It returns FALSE if there is an error.

Varování

Do not close the database connection before closing the large object resource.

To use the large object (lo) interface, it is necessary to enclose it within a transaction block.

Poznámka: This function used to be called pg_loopen().

pg_lo_read_all

(PHP 4 >= 4.2.0)

pg_lo_read_all -- Read a entire large object and send straight to browser

Description

int pg_lo_read_all ( resource large_object)

pg_lo_read_all() reads a large object and passes it straight through to the browser after sending all pending headers. Mainly intended for sending binary data like images or sound. It returns number of bytes read. It returns FALSE, if an error occurred.

To use the large object (lo) interface, it is necessary to enclose it within a transaction block.

Poznámka: This function used to be called pg_loreadall().

pg_lo_read

(PHP 4 >= 4.2.0)

pg_lo_read -- Read a large object

Description

string pg_lo_read ( resource large_object, int len)

pg_lo_read() reads at most len bytes from a large object and returns it as a string. large_object specifies a valid large object resource andlen specifies the maximum allowable size of the large object segment. It returns FALSE if there is an error.

To use the large object (lo) interface, it is necessary to enclose it within a transaction block.

Poznámka: This function used to be called pg_loread().

To use the large object (lo) interface, it is necessary to enclose it within a transaction block.

Poznámka: This function used to be called pg_lo_unlink().

pg_lo_write

(PHP 4 >= 4.2.0)

pg_lo_write -- Write a large object

Description

int pg_lo_write ( resource large_object, string data)

pg_lo_write() writes at most to a large object from a variable data and returns the number of bytes actually written, or FALSE in the case of an error. large_object is a large object resource from pg_lo_open().

To use the large object (lo) interface, it is necessary to enclose it within a transaction block.

Poznámka: This function used to be called pg_lo_write().

See also pg_lo_create() and pg_lo_open().

pg_metadata

(PHP 4 CVS only)

pg_metadata -- Get metadata for table.

Description

array pg_metadata ( resource connection, string table_name)

pg_metadata() returns table definition for table_name as array. If there is error, it returns FALSE

Poznámka: This function is experimental.

See also pg_convert()

pg_num_fields

(PHP 4 >= 4.2.0)

pg_num_fields -- Returns the number of fields

Description

int pg_num_fields ( resource result)

pg_num_fields() returns the number of fields (columns) in a PostgreSQL result. The argument is a result resource returned by pg_query(). This function will return -1 on error.

Poznámka: This function used to be called pg_numfields().

pg_num_rows

(PHP 4 >= 4.2.0)

pg_num_rows -- Returns the number of rows

Description

int pg_num_rows ( resource result)

pg_num_rows() will return the number of rows in a PostgreSQL result resource. result is a query result resource returned by pg_query(). This function will return -1 on error.

Poznámka: Use pg_affected_rows() to get number of rows affected by INSERT, UPDATE and DELETE query.

Poznámka: This function used to be called pg_numrows().

Poznámka: The application must explicitly send the two characters "\." on the last line to indicate to the backend that it has finished sending its data.

See also pg_end_copy().

Příklad 1. High-speed insertion of data into a table

<?php $conn = pg_pconnect ("dbname=foo"); pg_query($conn, "create table bar (a int4, b char(16), d float8)"); pg_query($conn, "copy bar from stdin"); pg_put_line($conn, "3\thello world\t4.5\n"); pg_put_line($conn, "4\tgoodbye world\t7.11\n"); pg_put_line($conn, "\\.\n"); pg_end_copy($conn); ?>

pg_query

(PHP 4 >= 4.2.0)

pg_query -- Execute a query

Description

resource pg_query ( resource connection, string query)

pg_query() returns a query result resource if query could be executed. It returns FALSE on failure or if connection is not a valid connection. Details about the error can be retrieved using the pg_last_error() function if connection is valid. pg_last_error() sends an SQL statement to the PostgreSQL database specified by the connection resource. The connection must be a valid connection that was returned by pg_connect() or pg_pconnect(). The return value of this function is an query result resource to be used to access the results from other PostgreSQL functions such as pg_fetch_array().

Poznámka: connection is a optional parameter for pg_query(). If connection is not set, default connection is used. Default connection is the last connection made by pg_connect() or pg_pconnect().

Although connection can be omitted, it is not recommended, since it could be a cause of hard to find bug in script.

Poznámka: This function used to be called pg_exec(). pg_exec() is still available for compatibility reasons but users are encouraged to use the newer name.

Příklad 1. pg_select

<?php 
    $db = pg_connect ('dbname=foo');
    // This is safe, since $_POST is converted autotmatically
    $rec = pg_select($db, 'post_log', $_POST);
    if ($rec) {
        echo "Records selected\n";
        var_dump($rec);
    }
    else {
        echo "User must have sent wrong inputs\n";
    }
?>

Poznámka: This function is experimental.

See also pg_convert()

pg_send_query

(PHP 4 >= 4.2.0)

pg_send_query -- Send asynchronous query

Description

bool pg_send_query ( resource connection, string query)

bool pg_send_query ( string query)

pg_send_query() send asynchronous query to the connection. Unlike pg_query(), it can send multiple query to PostgreSQL and get the result one by one using pg_get_result(). Script execution is not block while query is executing. Use pg_connection_busy() to check connection is busy (i.e. query is executing) Query may be canceled by calling pg_cancel_query().

Although, user can send multiple query at once. User cannot send multiple query over busy connection. If query is sent while connection is busy, it waits until last query is finished and discards all result.

pg_set_client_encoding

(PHP 3 CVS only, PHP 4 >= 4.0.3)

pg_set_client_encoding -- Set the client encoding

Description

int pg_set_client_encoding ( [resource connection, string encoding])

pg_set_client_encoding() sets the client encoding and return 0 if success or -1 if error.

encoding is the client encoding and can be either : SQL_ASCII, EUC_JP, EUC_CN, EUC_KR, EUC_TW, UNICODE, MULE_INTERNAL, LATINX (X=1...9), KOI8, WIN, ALT, SJIS, BIG5, WIN1250. Available encoding depends on your PostgreSQL and libpq version. Refer to PostgreSQL manual for supported encodings for your PostgreSQL.

Poznámka: This function requires PHP-4.0.3 or higher and PostgreSQL-7.0 or higher. Supported encoding depends on PostgreSQL version. Refer to PostgreSQL manual for details.

The function used to be called pg_setclientencoding().

pg_trace

(PHP 4 >= 4.0.1)

pg_trace -- Enable tracing a PostgreSQL connection

Description

bool pg_trace ( string pathname [, string mode [, resource connection]])

pg_trace() enables tracing of the PostgreSQL frontend/backend communication to a debugging file specified as pathname. To fully understand the results, one needs to be familiar with the internals of PostgreSQL communication protocol. For those who are not, it can still be useful for tracing errors in queries sent to the server, you could do for example grep '^To backend' trace.log and see what query actually were sent to the PostgreSQL server. For more information, refer to PostgreSQL manual.

Filename and mode are the same as in fopen() (mode defaults to 'w'), connection specifies the connection to trace and defaults to the last one opened.

It returns TRUE if pathname could be opened for logging, FALSE otherwise.

See also fopen() and pg_untrace().

pg_tty

(PHP 3, PHP 4 )

pg_tty -- Return the tty name associated with the connection

Description

string pg_tty ( resource connection)

pg_tty() returns the tty name that server side debugging output is sent to on the given PostgreSQL connection resource.

pg_untrace

(PHP 4 >= 4.0.1)

pg_untrace -- Disable tracing of a PostgreSQL connection

Description

bool pg_untrace ( [resource connection])

Stop tracing started by pg_trace(). connection specifies the connection that was traced and defaults to the last one opened.

Returns always TRUE.

pg_update

(PHP 4 CVS only)

pg_update -- Update table.

Description

long pg_update ( resource connection, string table_name, array condition, array data [, int options])

pg_update() updates records that matches condition with data If options is specified, pg_convert() is applied to assoc_array with specified options.

Příklad 1. pg_update

<?php 
    $db = pg_connect ('dbname=foo');
    $data = array('field1'=>'AA', 'field2'=>'BB');
    // This is safe, since $_POST is converted automatically
    $res = pg_update($db, 'post_log', $_POST, $data);
    if ($res) {
        echo "Data is updated: $res\n";
    }
    else {
        echo "User must have sent wrong inputs\n";
    }
?>

Poznámka: This function is experimental.

See also pg_convert()

LXXXI. Process Control Functions

Process Control support in PHP implements the Unix style of process creation, program execution, signal handling and process termination. Process Control should not be enabled within a webserver environment and unexpected results may happen if any Process Control functions are used within a webserver environment.

This documentation is intended to explain the general usage of each of the Process Control functions. For detailed information about Unix process control you are encouraged to consult your systems documentation including fork(2), waitpid(2) and signal(2) or a comprehensive reference such as Advanced Programming in the UNIX Environment by W. Richard Stevens (Addison-Wesley).

Process Control support in PHP is not enabled by default. You will need to use the --enable-pcntl configuration option when compiling PHP to enable Process Control support.

Poznámka: Currently, this module will not function on non-Unix platforms (Windows).

The following list of signals are supported by the Process Control functions. Please see your systems signal(7) man page for details of the default behavior of these signals.

Tabulka 1. Supported Signals

`SIGFPE`	`SIGCONT`	`SIGKILL`
`SIGSTOP`	`SIGUSR1`	`SIGTSTP`
`SIGHUP`	`SIGUSR2`	`SIGTTIN`
`SIGINT`	`SIGSEGV`	`SIGTTOU`
`SIGQUIT`	`SIGPIPE`	`SIGURG`
`SIGILL`	`SIGALRM`	`SIGXCPU`
`SIGTRAP`	`SIGTERM`	`SIGXFSZ`
`SIGABRT`	`SIGSTKFLT`	`SIGVTALRM`
`SIGIOT`	`SIGCHLD`	`SIGPROF`
`SIGBUS`	`SIGCLD`	`SIGWINCH`
`SIGPOLL`	`SIGIO`	`SIGPWR`
`SIGSYS`

Process Control Example

This example forks off a daemon process with a signal handler.

Příklad 1. Process Control Example

<?php

$pid = pcntl_fork();
if ($pid == -1) {
     die("could not fork"); 
} else if ($pid) {
     exit(); // we are the parent 
} else {
     // we are the child
}

// detatch from the controlling terminal
if (!posix_setsid()) {
    die("could not detach from terminal");
}

// setup signal handlers
pcntl_signal(SIGTERM, "sig_handler");
pcntl_signal(SIGHUP, "sig_handler");

// loop forever performing tasks
while(1) {

    // do something interesting here

}

function sig_handler($signo) {

     switch($signo) {
         case SIGTERM:
             // handle shutdown tasks
             exit;
             break;
         case SIGHUP:
             // handle restart tasks
             break;
         default:
             // handle all other signals
     }

}

?>

Obsah
pcntl_exec -- Executes specified program in current process space
pcntl_fork -- Forks the currently running process
pcntl_signal -- Installs a signal handler
pcntl_waitpid -- Waits on or returns the status of a forked child
pcntl_wexitstatus -- Returns the return code of a terminated child
pcntl_wifexited -- Returns TRUE if status code represents a successful exit
pcntl_wifsignaled -- Returns TRUE if status code represents a termination due to a signal
pcntl_wifstopped -- Returns TRUE if child process is currently stopped
pcntl_wstopsig -- Returns the signal which caused the child to stop
pcntl_wtermsig -- Returns the signal which caused the child to terminate

pcntl_exec

(PHP 4 >= 4.2.0)

pcntl_exec -- Executes specified program in current process space

Description

pcntl_waitpid() returns the process ID of the child which exited, -1 on error or zero if WNOHANG was used and no child was available

The value of pid can be one of the following:

Tabulka 1. possible values for pid

`< -1`	wait for any child process whose process group ID is equal to the absolute value of `pid`.
`-1`	wait for any child process; this is the same behaviour that the wait function exhibits.
`0`	wait for any child process whose process group ID is equal to that of the calling process.
`> 0`	wait for the child whose process ID is equal to the value of `pid`.

pcntl_waitpid() will store status information in the status parameter which can be evaluated using the following functions: pcntl_wifexited(), pcntl_wifstopped(), pcntl_wifsignaled(), pcntl_wexitstatus(), pcntl_wtermsig() and pcntl_wstopsig().

The value of options is the value of zero or more of the following two global constants OR'ed together:

Tabulka 2. possible values for options

`WNOHANG`	return immediately if no child has exited.
`WUNTRACED`	return for children which are stopped, and whose status has not been reported.

LXXXII. Funkce Spouštění Programů

Obsah
escapeshellarg -- ouvozovkování řetězce pro použití jako argument shellu
escapeshellcmd -- escape shellovské metaznaky
exec -- Provést externí program
passthru -- Vykonat externí program a zobrazit nezpracovaný výstup
proc_close -- Close a process opened by proc_open and return the exit code of that process.
proc_open -- Execute a command and open file pointers for input/output
shell_exec -- Execute command via shell and return complete output as string
system -- Provést externí program a zobrazit výstup

escapeshellarg

(PHP 4 >= 4.0.3)

escapeshellarg -- ouvozovkování řetězce pro použití jako argument shellu

Popis

string escapeshellarg ( string arg)

EscapeShellArg() přidá jednoduché uvozovky na začátek a konec řetězce a ouvozovkuje/escapes všechny výskyty jednoduchých uvozovek, takže tento řetězec můžete přímo předat shell funkci, přičemž tento bude brán jako bezpečný argument. Tato funkce by se měla používat k oescapování jednotlivých argumentů určených pro shell funkce pocházejících z uživatelského vstupu. Shell funkce zahrnujíc exec(), system() a backtick operator. Standardní použití:

system("ls ".EscapeShellArg($dir))

Viz také exec(), popen(), system(), a backtick operátor.

escapeshellcmd

(PHP 3, PHP 4 )

escapeshellcmd -- escape shellovské metaznaky

Popis

string escapeshellcmd ( string command)

EscapeShellCmd() oescapuje všechny znaky v řetězci, které by se daly použít ke zneužití shellového příkazu k vykonání libovolných příkazů. Tato funkce by se měla používat k zabezpečení toho, aby všechna data pocházející z uživatelského vstupu byla oescapována přetím, než budou předána funkci exec() nebo system(), nebo backtick operátoru. Standardní použití:

$e = EscapeShellCmd($userinput);
system("echo $e"); // tady nás nezajímá, jestli jsou v $e mezery
$f = EscapeShellCmd($filename);
system("touch \"/tmp/$f\"; ls -l \"/tmp/$f\""); // a tady ano, proto použijeme uvozovky

Viz takéescapeshellarg(), exec(), popen(), system(), a backtick operátor.

exec

(PHP 3, PHP 4 )

exec -- Provést externí program

Popis

string exec ( string command [, string array [, int return_var]])

exec() provádí předaný command, nicméně nic netiskne. Pouze vrací poslední řádek výstupu daného příkazu. Pokud potřebujete provést příkaz a nechat všechna data z tohoto příkazu předat rovnou bez jakéhokoli zásahu, použijte funkci PassThru().

Pokud je přítomen argument array, předané pole se naplní všemi řádky výstupu daného příkazu. Pozn.: Pokud toto pole už obsahuje nějaké prvky, exec() připojí tento výstup na konec tohoto pole. Pokud nechcete, aby tato funkce připojovala prvky na konec daného pole, zavolejte na toto pole unset() předtím, než ho předáte funkci exec().

Pokud je vedle argumentu array přítomen argument return_var, návratová hodnota provedeného příkazu se zapíše do této proměnné.

Pozn.: Pokud chcete používat v této funkci data z uživatelského vstupu, měli byste používat EscapeShellCmd(), abyste měli jistotu, že uživatelé nevmanipulují systém do provádění libovolných příkazů.

Pozn.: Pokud touto funkcí nastartujete nějaký program a chcete ho nechat běžet v pozadí, musíte se zajistit přesměrování výstupu z tohoto programu do souboru nebo jineho výstupního streamu, jinak se PHP zasekne až do ukončení běhu tohoto programu.

Viz takésystem(), PassThru(), popen(), EscapeShellCmd(), a backtick operátor.

passthru

(PHP 3, PHP 4 )

passthru -- Vykonat externí program a zobrazit nezpracovaný výstup

Popis

void passthru ( string command [, int return_var])

Funkce passthru() se podobá funkci exec() v tom ohledu, že provede command. Pokud je přítomen argument return_var, návratová hodnota tohoto příkazu se umístí sem. Tato funkce by se měla používat místo exec() a system(), pokud jsou výstupem daného příkazu binární data, která je potřeba odeslat přímo do browseru. Běžným použitím této funkce vykonat např. pbmplus utility, které mohou poslat stream obrázku na stdout. Nastavením content-type na image/gif a zavoláním pbmplus programu k odeslání gifu na stdout gifu můžete vytvořit PHP skripty, které přímo tvoří obrázky.

Viz takéexec(), system(), popen(), EscapeShellCmd(), a backtick operátor.

proc_close

(PHP 4 CVS only)

proc_close -- Close a process opened by proc_open and return the exit code of that process.

Description

int proc_close ( resource process)

proc_close() is similar to pclose() except that it only works on processes opened by proc_open(). proc_close() waits for the process to terminate, and returns it's exit code. If you have open pipes to that process, you should fclose() them prior to calling this function in order to avoid a deadlock - the child process may not be able to exit while the pipes are open.

proc_open

(PHP 4 CVS only)

proc_open -- Execute a command and open file pointers for input/output

Description

resource proc_open ( string cmd, array descriptorspec, array pipes)

proc_open() is similar to popen() but provides a much greater degree of control over the program execution. cmd is the command to be executed by the shell. descriptorspec is an indexed array where the key represents the descriptor number and the value represents how PHP will pass that descriptor to the child process. pipes will be set to an indexed array of file pointers that correspond to PHP's end of any pipes that are created. The return value is a resource representing the process; you should free it using proc_close() when you are finished with it.

$descriptorspec = array(
   0 => array("pipe", "r"),  // stdin is a pipe that the child will read from
   1 => array("pipe", "w"),  // stdout is a pipe that the child will write to
   2 => array("file", "/tmp/error-output.txt", "a"), // stderr is a file to write to
);
$process = proc_open("php", $descriptorspec, $pipes);
if (is_resource($process)) {
    // $pipes now looks like this:
    // 0 => writeable handle connected to child stdin
    // 1 => readable handle connected to child stdout
    // Any error output will be appended to /tmp/error-output.txt

    fwrite($pipes[0], "<?php echo \"Hello World!\"; ?>");
    fclose($pipes[0]);

    while(!feof($pipes[1])) {
        echo fgets($pipes[1], 1024);
    }
    fclose($pipes[1]);
    // It is important that you close any pipes before calling
    // proc_close in order to avoid a deadlock
    $return_value = proc_close($process);

    echo "command returned $return_value\n";
}

The file descriptor numbers in descriptorspec are not limited to 0, 1 and 2 - you may specify any valid file descriptor number and it will be passed to the child process. This allows your script to interoperate with other scripts that run as "co-processes". In particular, this is useful for passing passphrases to programs like PGP, GPG and openssl in a more secure manner. It is also useful for reading status information provided by those programs on auxillary file descriptors.

Poznámka: Windows compatibility: Descriptors beyond 2 (stderr) are made available to the child process as inheritable handles, but since the Windows architecture does not associate file descriptor numbers with low-level handles, the child process does not (yet) have a means of accessing those handles. Stdin, stdout and stderr work as expected.

Poznámka: This function was introduced in PHP 4.3.0.

Poznámka: If you only need a uni-directional (one-way) process pipe, use popen() instead, as it is much easier to use.

shell_exec

(PHP 4 )

shell_exec -- Execute command via shell and return complete output as string

Description

string shell_exec ( string cmd)

This function is identical to the backtick operator.

system

(PHP 3, PHP 4 )

system -- Provést externí program a zobrazit výstup

Popis

string system ( string command [, int return_var])

system() je verzí stejnojmenné C funkce; vykoná předaný command a zobrazí výstup. Pokud jí předáte proměnnou jako druhý argument, návratová hodnota provedeného příkazu se zapíše do této proměnné.

Pokud PHP běží jako modul serveru, system() také automaticky flushne výstupní buffer web serveru po každém řádku výstupu.

Při úspěchu vrací poslední řádek výstupu příkazu, při selhání FALSE.

Pokud potřebujete provést příkaz a nechat všechna data z tohoto příkazu předat rovnou bez jakéhokoli zásahu, použijte funkci PassThru().

Viz takéexec(), PassThru(), popen(), EscapeShellCmd(), a backtick operátor.

LXXXIII. Printer functions

These functions are only available under Windows 9.x, ME, NT4 and 2000. They have been added in PHP 4 (4.0.4).

Obsah
printer_abort -- Deletes the printer's spool file
printer_close -- Close an open printer connection
printer_create_brush -- Create a new brush
printer_create_dc -- Create a new device context
printer_create_font -- Create a new font
printer_create_pen -- Create a new pen
printer_delete_brush -- Delete a brush
printer_delete_dc -- Delete a device context
printer_delete_font -- Delete a font
printer_delete_pen -- Delete a pen
printer_draw_bmp -- Draw a bmp
printer_draw_chord -- Draw a chord
printer_draw_elipse -- Draw an ellipse
printer_draw_line -- Draw a line
printer_draw_pie -- Draw a pie
printer_draw_rectangle -- Draw a rectangle
printer_draw_roundrect -- Draw a rectangle with rounded corners
printer_draw_text -- Draw text
printer_end_doc -- Close document
printer_end_page -- Close active page
printer_get_option -- Retrieve printer configuration data
printer_list -- Return an array of printers attached to the server
printer_logical_fontheight -- Get logical font height
printer_open -- Open connection to a printer
printer_select_brush -- Select a brush
printer_select_font -- Select a font
printer_select_pen -- Select a pen
printer_set_option -- Configure the printer connection
printer_start_doc -- Start a new document
printer_start_page -- Start a new page
printer_write -- Write data to the printer

printer_abort

(unknown)

printer_abort -- Deletes the printer's spool file

Description

void printer_abort ( resource handle)

This function deletes the printers spool file.

handle must be a valid handle to a printer.

Příklad 1. printer_abort() example

$handle = printer_open();
printer_abort($handle);
printer_close($handle);

printer_close

(unknown)

printer_close -- Close an open printer connection

Description

void printer_close ( resource handle)

This function closes the printer connection. printer_close() also closes the active device context.

handle must be a valid handle to a printer.

Příklad 1. printer_close() example

$handle = printer_open();
printer_close($handle);

printer_create_brush

(unknown)

printer_create_brush -- Create a new brush

Description

mixed printer_create_brush ( int style, string color)

The function creates a new brush and returns a handle to it. A brush is used to fill shapes. For an example see printer_select_brush(). color must be a color in RGB hex format, i.e. "000000" for black, style must be one of the following constants:

PRINTER_BRUSH_SOLID: creates a brush with a solid color.
PRINTER_BRUSH_DIAGONAL: creates a brush with a 45-degree upward left-to-right hatch ( / ).
PRINTER_BRUSH_CROSS: creates a brush with a cross hatch ( + ).
PRINTER_BRUSH_DIAGCROSS: creates a brush with a 45 cross hatch ( x ).
PRINTER_BRUSH_FDIAGONAL: creates a brush with a 45-degree downward left-to-right hatch ( \ ).
PRINTER_BRUSH_HORIZONTAL: creates a brush with a horizontal hatch ( - ).
PRINTER_BRUSH_VERTICAL: creates a brush with a vertical hatch ( | ).
PRINTER_BRUSH_CUSTOM: creates a custom brush from an BMP file. The second parameter is used to specify the BMP instead of the RGB color code.

printer_create_dc

(unknown)

printer_create_dc -- Create a new device context

Description

void printer_create_dc ( resource handle)

The function creates a new device context. A device context is used to customize the graphic objects of the document. handle must be a valid handle to a printer.

Příklad 1. printer_create_dc() example

$handle = printer_open();
printer_start_doc($handle);
printer_start_page($handle);

printer_create_dc($handle);
/* do some stuff with the dc */
printer_set_option($handle, PRINTER_TEXT_COLOR, "333333");
printer_draw_text($handle, 1, 1, "text");
printer_delete_dc($handle);

/* create another dc */
printer_create_dc($handle);
printer_set_option($handle, PRINTER_TEXT_COLOR, "000000");
printer_draw_text($handle, 1, 1, "text");
/* do some stuff with the dc */

printer_delete_dc($handle);

printer_endpage($handle);
printer_end_doc($handle);
printer_close($handle);

printer_create_font

(unknown)

printer_create_font -- Create a new font

Description

mixed printer_create_font ( string face, int height, int width, int font_weight, bool italic, bool underline, bool strikeout, int orientaton)

The function creates a new font and returns a handle to it. A font is used to draw text. For an example see printer_select_font(). face must be a string specifying the font face. height specifies the font height, and width the font width. The font_weight specifies the font weight (400 is normal), and can be one of the following predefined constants.

PRINTER_FW_THIN: sets the font weight to thin (100).
PRINTER_FW_ULTRALIGHT: sets the font weight to ultra light (200).
PRINTER_FW_LIGHT: sets the font weight to light (300).
PRINTER_FW_NORMAL: sets the font weight to normal (400).
PRINTER_FW_MEDIUM: sets the font weight to medium (500).
PRINTER_FW_BOLD: sets the font weight to bold (700).
PRINTER_FW_ULTRABOLD: sets the font weight to ultra bold (800).
PRINTER_FW_HEAVY: sets the font weight to heavy (900).

italic can be TRUE or FALSE, and sets whether the font should be italic.

underline can be TRUE or FALSE, and sets whether the font should be underlined.

strikeout can be TRUE or FALSE, and sets whether the font should be striked out.

orientation specifies a rotation. For an example see printer_select_font().

printer_create_pen

(unknown)

printer_create_pen -- Create a new pen

Description

mixed printer_create_pen ( int style, int width, string color)

The function creates a new pen and returns a handle to it. A pen is used to draw lines and curves. For an example see printer_select_pen(). color must be a color in RGB hex format, i.e. "000000" for black, width specifies the width of the pen whereas style must be one of the following constants:

PRINTER_PEN_SOLID: creates a solid pen.
PRINTER_PEN_DASH: creates a dashed pen.
PRINTER_PEN_DOT: creates a dotted pen.
PRINTER_PEN_DASHDOT: creates a pen with dashes and dots.
PRINTER_PEN_DASHDOTDOT: creates a pen with dashes and double dots.
PRINTER_PEN_INVISIBLE: creates an invisible pen.

The function returns TRUE on success, or otherwise FALSE.

Příklad 1. printer_draw_bmp() example

$handle = printer_open();
printer_start_doc($handle, "My Document");
printer_start_page($handle);

printer_draw_bmp($handle, "c:\\image.bmp", 1, 1);

printer_end_page($handle);
printer_end_doc($handle);
printer_close($handle);

printer_draw_chord

(unknown)

printer_draw_chord -- Draw a chord

Description

void printer_draw_chord ( resource handle, int rec_x, int rec_y, int rec_x1, int rec_y1, int rad_x, int rad_y, int rad_x1, int rad_y1)

The function simply draws an chord. handle must be a valid handle to a printer.

rec_x is the upper left x coordinate of the bounding rectangle.

rec_y is the upper left y coordinate of the bounding rectangle.

rec_x1 is the lower right x coordinate of the bounding rectangle.

rec_y1 is the lower right y coordinate of the bounding rectangle.

rad_x is x coordinate of the radial defining the beginning of the chord.

rad_y is y coordinate of the radial defining the beginning of the chord.

rad_x1 is x coordinate of the radial defining the end of the chord.

rad_y1 is y coordinate of the radial defining the end of the chord.

Příklad 1. printer_draw_chord() example

$handle = printer_open();
printer_start_doc($handle, "My Document");
printer_start_page($handle);

$pen = printer_create_pen(PRINTER_PEN_SOLID, 2, "000000");
printer_select_pen($handle, $pen);

$brush = printer_create_brush(PRINTER_BRUSH_SOLID, "2222FF");
printer_select_brush($handle, $brush);

printer_draw_chord($handle, 1, 1, 500, 500, 1, 1, 500, 1);

printer_delete_brush($brush);
printer_delete_pen($pen);

printer_end_page($handle);
printer_end_doc($handle);
printer_close($handle);

printer_draw_elipse

(unknown)

printer_draw_elipse -- Draw an ellipse

Description

void printer_draw_elipse ( resource handle, int ul_x, int ul_y, int lr_x, int lr_y)

The function simply draws an ellipse. handle must be a valid handle to a printer.

ul_x is the upper left x coordinate of the ellipse.

ul_y is the upper left y coordinate of the ellipse.

lr_x is the lower right x coordinate of the ellipse.

lr_y is the lower right y coordinate of the ellipse.

Příklad 1. printer_draw_elipse() example

$handle = printer_open();
printer_start_doc($handle, "My Document");
printer_start_page($handle);

$pen = printer_create_pen(PRINTER_PEN_SOLID, 2, "000000");
printer_select_pen($handle, $pen);

$brush = printer_create_brush(PRINTER_BRUSH_SOLID, "2222FF");
printer_select_brush($handle, $brush);

printer_draw_elipse($handle, 1, 1, 500, 500);

printer_delete_brush($brush);
printer_delete_pen($pen);

printer_end_page($handle);
printer_end_doc($handle);
printer_close($handle);

printer_draw_line

(unknown)

printer_draw_line -- Draw a line

Description

void printer_draw_line ( resource printer_handle, int from_x, int from_y, int to_x, int to_y)

The function simply draws a line from position from_x, from_y to position to_x, to_y using the selected pen. printer_handle must be a valid handle to a printer.

Příklad 1. printer_draw_line() example

$handle = printer_open();
printer_start_doc($handle, "My Document");
printer_start_page($handle);

$pen = printer_create_pen(PRINTER_PEN_SOLID, 30, "000000");
printer_select_pen($handle, $pen);

printer_draw_line($handle, 1, 10, 1000, 10);
printer_draw_line($handle, 1, 60, 500, 60);

printer_delete_pen($pen);

printer_end_page($handle);
printer_end_doc($handle);
printer_close($handle);

printer_draw_pie

(unknown)

printer_draw_pie -- Draw a pie

Description

void printer_draw_pie ( resource handle, int rec_x, int rec_y, int rec_x1, int rec_y1, int rad1_x, int rad1_y, int rad2_x, int rad2_y)

The function simply draws an pie. handle must be a valid handle to a printer.

rec_x is the upper left x coordinate of the bounding rectangle.

rec_y is the upper left y coordinate of the bounding rectangle.

rec_x1 is the lower right x coordinate of the bounding rectangle.

rec_y1 is the lower right y coordinate of the bounding rectangle.

rad1_x is x coordinate of the first radial's ending.

rad1_y is y coordinate of the first radial's ending.

rad2_x is x coordinate of the second radial's ending.

rad2_y is y coordinate of the second radial's ending.

Příklad 1. printer_draw_pie() example

$handle = printer_open();
printer_start_doc($handle, "My Document");
printer_start_page($handle);

$pen = printer_create_pen(PRINTER_PEN_SOLID, 2, "000000");
printer_select_pen($handle, $pen);

$brush = printer_create_brush(PRINTER_BRUSH_SOLID, "2222FF");
printer_select_brush($handle, $brush);

printer_draw_pie($handle, 1, 1, 500, 500, 1, 1, 500, 1);

printer_delete_brush($brush);
printer_delete_pen($pen);

printer_end_page($handle);
printer_end_doc($handle);
printer_close($handle);

printer_draw_rectangle

(unknown)

printer_draw_rectangle -- Draw a rectangle

Description

void printer_draw_rectangle ( resource handle, int ul_x, int ul_y, int lr_x, int lr_y)

The function simply draws a rectangle.

handle must be a valid handle to a printer.

ul_x is the upper left x coordinate of the rectangle.

ul_y is the upper left y coordinate of the rectangle.

lr_x is the lower right x coordinate of the rectangle.

lr_y is the lower right y coordinate of the rectangle.

Příklad 1. printer_draw_rectangle() example

$handle = printer_open();
printer_start_doc($handle, "My Document");
printer_start_page($handle);

$pen = printer_create_pen(PRINTER_PEN_SOLID, 2, "000000");
printer_select_pen($handle, $pen);

$brush = printer_create_brush(PRINTER_BRUSH_SOLID, "2222FF");
printer_select_brush($handle, $brush);

printer_draw_rectangle($handle, 1, 1, 500, 500);

printer_delete_brush($brush);
printer_delete_pen($pen);

printer_end_page($handle);
printer_end_doc($handle);
printer_close($handle);

printer_draw_roundrect

(unknown)

printer_draw_roundrect -- Draw a rectangle with rounded corners

Description

void printer_draw_roundrect ( resource handle, int ul_x, int ul_y, int lr_x, int lr_y, int width, int height)

The function simply draws a rectangle with rounded corners.

handle must be a valid handle to a printer.

ul_x is the upper left x coordinate of the rectangle.

ul_y is the upper left y coordinate of the rectangle.

lr_x is the lower right x coordinate of the rectangle.

lr_y is the lower right y coordinate of the rectangle.

width is the width of the ellipse.

height is the height of the ellipse.

Příklad 1. printer_draw_roundrect() example

$handle = printer_open();
printer_start_doc($handle, "My Document");
printer_start_page($handle);

$pen = printer_create_pen(PRINTER_PEN_SOLID, 2, "000000");
printer_select_pen($handle, $pen);

$brush = printer_create_brush(PRINTER_BRUSH_SOLID, "2222FF");
printer_select_brush($handle, $brush);

printer_draw_roundrect($handle, 1, 1, 500, 500, 200, 200);

printer_delete_brush($brush);
printer_delete_pen($pen);

printer_end_page($handle);
printer_end_doc($handle);
printer_close($handle);

printer_draw_text

(unknown)

printer_draw_text -- Draw text

Description

void printer_draw_text ( resource printer_handle, string text, int x, int y)

The function simply draws text at position x, y using the selected font. printer_handle must be a valid handle to a printer.

Příklad 1. printer_draw_text() example

$handle = printer_open();
printer_start_doc($handle, "My Document");
printer_start_page($handle);

$font = printer_create_font("Arial",72,48,400,false,false,false,0);
printer_select_font($handle, $font);
printer_draw_text($handle, "test", 10, 10);
printer_delete_font($font);

printer_end_page($handle);
printer_end_doc($handle);
printer_close($handle);

PRINTER_DEVICENAME returns the devicename of the printer.
PRINTER_DRIVERVERSION returns the printer driver version.

Příklad 1. printer_get_option() example

$handle = printer_open();
print printer_get_option($handle, PRINTER_DRIVERVERSION);
printer_close($handle);

printer_list

(unknown)

printer_list -- Return an array of printers attached to the server

Description

array printer_list ( int enumtype [, string name [, int level]])

The function enumerates available printers and their capabilities. level sets the level of information request. Can be 1,2,4 or 5. enumtype must be one of the following predefined constants:

PRINTER_ENUM_LOCAL: enumerates the locally installed printers.
PRINTER_ENUM_NAME: enumerates the printer of name, can be a server, domain or print provider.
PRINTER_ENUM_SHARED: this parameter can't be used alone, it has to be OR'ed with other parameters, i.e. PRINTER_ENUM_LOCAL to detect the locally shared printers.
PRINTER_ENUM_DEFAULT: (Win9.x only) enumerates the default printer.
PRINTER_ENUM_CONNECTIONS: (WinNT/2000 only) enumerates the printers to which the user has made connections.
PRINTER_ENUM_NETWORK: (WinNT/2000 only) enumerates network printers in the computer's domain. Only valid if level is 1.
PRINTER_ENUM_REMOTE: (WinNT/2000 only) enumerates network printers and print servers in the computer's domain. Only valid if level is 1.

Příklad 1. printer_list() example

/* detect locally shared printer */
var_dump( printer_list(PRINTER_ENUM_LOCAL | PRINTER_ENUM_SHARED) );

printer_logical_fontheight

(unknown)

printer_logical_fontheight -- Get logical font height

Description

int printer_logical_fontheight ( resource handle, int height)

The function calculates the logical font height of height. handle must be a valid handle to a printer.

Příklad 1. printer_logical_fontheight() example

$handle = printer_open();
print printer_logical_fontheight($handle, 72);
printer_close($handle);

printer_open

(unknown)

printer_open -- Open connection to a printer

Description

mixed printer_open ( [string devicename])

This function tries to open a connection to the printer devicename, and returns a handle on success or FALSE on failure.

If no parameter was given it tries to open a connection to the default printer (if not specified in php.ini as printer.default_printer, php tries to detect it).

printer_open() also starts a device context.

Příklad 1. printer_open() example

$handle = printer_open("HP Deskjet 930c");
$handle = printer_open();

printer_select_brush

(unknown)

printer_select_brush -- Select a brush

Description

void printer_select_brush ( resource printer_handle, resource brush_handle)

The function selects a brush as the active drawing object of the actual device context. A brush is used to fill shapes. If you draw an rectangle the brush is used to draw the shapes, while the pen is used to draw the border. If you haven't selected a brush before drawing shapes, the shape won't be filled. printer_handle must be a valid handle to a printer. brush_handle must be a valid handle to a brush.

Příklad 1. printer_select_brush() example

$handle = printer_open();
printer_start_doc($handle, "My Document");
printer_start_page($handle);

$pen = printer_create_pen(PRINTER_PEN_SOLID, 2, "000000");
printer_select_pen($handle, $pen);
$brush = printer_create_brush(PRINTER_BRUSH_CUSTOM, "c:\\brush.bmp");
printer_select_brush($handle, $brush);

printer_draw_rectangle($handle, 1,1,500,500);

printer_delete_brush($brush);

$brush = printer_create_brush(PRINTER_BRUSH_SOLID, "000000");
printer_select_brush($handle, $brush);
printer_draw_rectangle($handle, 1,501,500,1001);
printer_delete_brush($brush);

printer_delete_pen($pen);

printer_end_page($handle);
printer_end_doc($handle);
printer_close($handle);

printer_select_font

(unknown)

printer_select_font -- Select a font

Description

void printer_select_font ( resource printer_handle, resource font_handle)

The function selects a font to draw text. printer_handle must be a valid handle to a printer. font_handle must be a valid handle to a font.

Příklad 1. printer_select_font() example

$handle = printer_open();
printer_start_doc($handle, "My Document");
printer_start_page($handle);

$font = printer_create_font("Arial", 148, 76, PRINTER_FW_MEDIUM, false, false, false, -50);
printer_select_font($handle, $font);
printer_draw_text($handle, "PHP is simply cool", 40, 40);
printer_delete_font($font);

printer_end_page($handle);
printer_end_doc($handle);
printer_close($handle);

printer_select_pen

(unknown)

printer_select_pen -- Select a pen

Description

void printer_select_pen ( resource printer_handle, resource pen_handle)

The function selects a pen as the active drawing object of the actual device context. A pen is used to draw lines and curves. I.e. if you draw a single line the pen is used. If you draw an rectangle the pen is used to draw the borders, while the brush is used to fill the shape. If you haven't selected a pen before drawing shapes, the shape won't be outlined. printer_handle must be a valid handle to a printer. pen_handle must be a valid handle to a pen.

Příklad 1. printer_select_pen() example

$handle = printer_open();
printer_start_doc($handle, "My Document");
printer_start_page($handle);

$pen = printer_create_pen(PRINTER_PEN_SOLID, 30, "2222FF");
printer_select_pen($handle, $pen);

printer_draw_line($handle, 1, 60, 500, 60);

printer_delete_pen($pen);

printer_end_page($handle);
printer_end_doc($handle);
printer_close($handle);

printer_set_option

(unknown)

printer_set_option -- Configure the printer connection

Description

bool printer_set_option ( resource handle, int option, mixed value)

The function sets the following options for the current connection. handle must be a valid handle to a printer. For option can be one of the following constants:

PRINTER_COPIES: sets how many copies should be printed, value must be an integer.
PRINTER_MODE: specifies the type of data (text, raw or emf), value must be a string.
PRINTER_TITLE: specifies the name of the document, value must be a string.
PRINTER_ORIENTATION: specifies the orientation of the paper, value can be either PRINTER_ORIENTATION_PORTRAIT or PRINTER_ORIENTATION_LANDSCAPE
PRINTER_RESOLUTION_Y: specifies the y-resolution in DPI, value must be an integer.
PRINTER_RESOLUTION_X: specifies the x-resolution in DPI, value must be an integer.
PRINTER_PAPER_FORMAT: specifies the a predefined paper format, set value to PRINTER_FORMAT_CUSTOM if you want to specify a custom format with PRINTER_PAPER_WIDTH and PRINTER_PAPER_LENGTH. value can be one of the following constants.
- PRINTER_FORMAT_CUSTOM: let's you specify a custom paper format.
- PRINTER_FORMAT_LETTER: specifies standard letter format (8 1/2- by 11-inches).
- PRINTER_FORMAT_LETTER: specifies standard legal format (8 1/2- by 14-inches).
- PRINTER_FORMAT_A3: specifies standard A3 format (297- by 420-millimeters).
- PRINTER_FORMAT_A4: specifies standard A4 format (210- by 297-millimeters).
- PRINTER_FORMAT_A5: specifies standard A5 format (148- by 210-millimeters).
- PRINTER_FORMAT_B4: specifies standard B4 format (250- by 354-millimeters).
- PRINTER_FORMAT_B5: specifies standard B5 format (182- by 257-millimeter).
- PRINTER_FORMAT_FOLIO: specifies standard FOLIO format (8 1/2- by 13-inch).
PRINTER_PAPER_LENGTH: if PRINTER_PAPER_FORMAT is set to PRINTER_FORMAT_CUSTOM, PRINTER_PAPER_LENGTH specifies a custom paper length in mm, value must be an integer.
PRINTER_PAPER_WIDTH: if PRINTER_PAPER_FORMAT is set to PRINTER_FORMAT_CUSTOM, PRINTER_PAPER_WIDTH specifies a custom paper width in mm, value must be an integer.
PRINTER_SCALE: specifies the factor by which the printed output is to be scaled. the page size is scaled from the physical page size by a factor of scale/100. for example if you set the scale to 50, the output would be half of it's original size. value must be an integer.
PRINTER_BACKGROUND_COLOR: specifies the background color for the actual device context, value must be a string containing the rgb information in hex format i.e. "005533".
PRINTER_TEXT_COLOR: specifies the text color for the actual device context, value must be a string containing the rgb information in hex format i.e. "005533".
PRINTER_TEXT_ALIGN: specifies the text alignment for the actual device context, value can be combined through OR'ing the following constants:
- PRINTER_TA_BASELINE: text will be aligned at the base line.
- PRINTER_TA_BOTTOM: text will be aligned at the bottom.
- PRINTER_TA_TOP: text will be aligned at the top.
- PRINTER_TA_CENTER: text will be aligned at the center.
- PRINTER_TA_LEFT: text will be aligned at the left.
- PRINTER_TA_RIGHT: text will be aligned at the right.

Příklad 1. printer_set_option() example

$handle = printer_open();
printer_set_option($handle, PRINTER_SCALE, 75);
printer_set_option($handle, PRINTER_TEXT_ALIGN, PRINTER_TA_LEFT);
printer_close($handle);

printer_start_doc

(unknown)

printer_start_doc -- Start a new document

Description

bool printer_start_doc ( resource handle [, string document])

The function creates a new document in the printer spooler. A document can contain multiple pages, it's used to schedule the print job in the spooler. handle must be a valid handle to a printer. The optional parameter document can be used to set an alternative document name.

Příklad 1. printer_start_doc() example

$handle = printer_open();
printer_start_doc($handle, "My Document");
printer_start_page($handle);

printer_end_page($handle);
printer_end_doc($handle);
printer_close($handle);

printer_start_page

(unknown)

printer_start_page -- Start a new page

Description

bool printer_start_page ( resource handle)

The function creates a new page in the active document. For an example see printer_start_doc(). handle must be a valid handle to a printer.

printer_write

(unknown)

printer_write -- Write data to the printer

Description

bool printer_write ( resource handle, string content)

Writes content directly to the printer, and returns TRUE on success or FALSE if it failed.

handle must be a valid handle to a printer.

Příklad 1. printer_write() example

$handle = printer_open();
printer_write($handle, "Text to print");
printer_close($handle);

LXXXIV. Pspell Functions

These functions allow you to check the spelling of a word and offer suggestions.

You need the aspell and pspell libraries, available from http://aspell.sourceforge.net/ and http://aspell.net/ respectively, and add the --with-pspell[=dir] option when compiling php.

Obsah
pspell_add_to_personal -- Add the word to a personal wordlist
pspell_add_to_session -- Add the word to the wordlist in the current session
pspell_check -- Check a word
pspell_clear_session -- Clear the current session
pspell_config_create -- Create a config used to open a dictionary
pspell_config_ignore -- Ignore words less than N characters long
pspell_config_mode -- Change the mode number of suggestions returned
pspell_config_personal -- Set a file that contains personal wordlist
pspell_config_repl -- Set a file that contains replacement pairs
pspell_config_runtogether -- Consider run-together words as valid compounds
pspell_config_save_repl -- Determine whether to save a replacement pairs list along with the wordlist
pspell_new_config -- Load a new dictionary with settings based on a given config
pspell_new_personal -- Load a new dictionary with personal wordlist
pspell_new -- Load a new dictionary
pspell_save_wordlist -- Save the personal wordlist to a file
pspell_store_replacement -- Store a replacement pair for a word
pspell_suggest -- Suggest spellings of a word

pspell_add_to_personal

(PHP 4 >= 4.0.2)

pspell_add_to_personal -- Add the word to a personal wordlist

Description

int pspell_add_to_personal ( int dictionary_link, string word)

pspell_add_to_personal() adds a word to the personal wordlist. If you used pspell_new_config() with pspell_config_personal() to open the dictionary, you can save the wordlist later with pspell_save_wordlist(). Please, note that this function will not work unless you have pspell .11.2 and aspell .32.5 or later.

Příklad 1. pspell_add_to_personal()

$pspell_config = pspell_config_create ("en"); pspell_config_personal ($pspell_config, "/var/dictionaries/custom.pws"); $pspell_link = pspell_new_config ($pspell_config); pspell_add_to_personal ($pspell_link, "Vlad"); pspell_save_wordlist ($pspell_link);

pspell_add_to_session

(PHP 4 >= 4.0.2)

pspell_add_to_session -- Add the word to the wordlist in the current session

Description

int pspell_add_to_session ( int dictionary_link, string word)

pspell_add_to_session() adds a word to the wordlist associated with the current session. It is very similar to pspell_add_to_personal()

pspell_check

(PHP 4 >= 4.0.2)

pspell_check -- Check a word

Description

bool pspell_check ( int dictionary_link, string word)

pspell_check() checks the spelling of a word and returns TRUE if the spelling is correct, FALSE if not.

Příklad 1. pspell_check()

$pspell_link = pspell_new ("en"); if (pspell_check ($pspell_link, "testt")) { echo "This is a valid spelling"; } else { echo "Sorry, wrong spelling"; }

pspell_clear_session

(PHP 4 >= 4.0.2)

pspell_clear_session -- Clear the current session

Description

int pspell_clear_session ( int dictionary_link)

pspell_clear_session() clears the current session. The current wordlist becomes blank, and, for example, if you try to save it with pspell_save_wordlist(), nothing happens.

pspell_config_create

(PHP 4 >= 4.0.2)

pspell_config_create -- Create a config used to open a dictionary

Description

int pspell_config_create ( string language [, string spelling [, string jargon [, string encoding]]])

pspell_config_create() has a very similar syntax to pspell_new(). In fact, using pspell_config_create() immediatelly followed by pspell_new_config() will produce the exact same result. However, after creating a new config, you can also use pspell_config_*() functions before calling pspell_new_config() to take advantage of some advanced functionality.

The language parameter is the language code which consists of the two letter ISO 639 language code and an optional two letter ISO 3166 country code after a dash or underscore.

The spelling parameter is the requested spelling for languages with more than one spelling such as English. Known values are 'american', 'british', and 'canadian'.

The jargon parameter contains extra information to distinguish two different words lists that have the same language and spelling parameters.

The encoding parameter is the encoding that words are expected to be in. Valid values are 'utf-8', 'iso8859-*', 'koi8-r', 'viscii', 'cp1252', 'machine unsigned 16', 'machine unsigned 32'. This parameter is largely untested, so be careful when using.

The mode parameter is the mode in which spellchecker will work. There are several modes available:

PSPELL_FAST - Fast mode (least number of suggestions)
PSPELL_NORMAL - Normal mode (more suggestions)
PSPELL_BAD_SPELLERS - Slow mode (a lot of suggestions)

For more information and examples, check out inline manual pspell website:http://aspell.net/.

Příklad 1. pspell_config_create()

$pspell_config = pspell_config_create ("en"); pspell_config_personal ($pspell_config, "/var/dictionaries/custom.pws"); pspell_config_repl ($pspell_config, "/var/dictionaries/custom.repl"); $pspell_link = pspell_new_personal ($pspell_config, "en");

pspell_config_ignore

(PHP 4 >= 4.0.2)

pspell_config_ignore -- Ignore words less than N characters long

Description

int pspell_config_ignore ( int dictionary_link, int n)

pspell_config_ignore() should be used on a config before calling pspell_new_config(). This function allows short words to be skipped by the spellchecker. Words less then n characters will be skipped.

Příklad 1. pspell_config_ignore()

$pspell_config = pspell_config_create ("en"); pspell_config_ignore($pspell_config, 5); $pspell_link = pspell_new_config($pspell_config); pspell_check($pspell_link, "abcd"); //will not result in an error

pspell_config_mode

(PHP 4 >= 4.0.2)

pspell_config_mode -- Change the mode number of suggestions returned

Description

int pspell_config_mode ( int dictionary_link, int mode)

pspell_config_mode() should be used on a config before calling pspell_new_config(). This function determines how many suggestions will be returned by pspell_suggest().

The mode parameter is the mode in which spellchecker will work. There are several modes available:

PSPELL_FAST - Fast mode (least number of suggestions)
PSPELL_NORMAL - Normal mode (more suggestions)
PSPELL_BAD_SPELLERS - Slow mode (a lot of suggestions)

pspell_new_config

(PHP 4 >= 4.0.2)

pspell_new_config -- Load a new dictionary with settings based on a given config

Description

int pspell_new_config ( int config)

pspell_new_config() opens up a new dictionary with settings specified in a config, created with with pspell_config_create() and modified with pspell_config_*() functions. This method provides you with the most flexibility and has all the functionality provided by pspell_new() and pspell_new_personal().

The config parameter is the one returned by pspell_config_create() when the config was created.

Příklad 1. pspell_new_config()

$pspell_config = pspell_config_create ("en"); pspell_config_personal ($pspell_config, "/var/dictionaries/custom.pws"); pspell_config_repl ($pspell_config, "/var/dictionaries/custom.repl"); $pspell_link = pspell_new_config ($pspell_config);

pspell_new_personal

(PHP 4 >= 4.0.2)

pspell_new_personal -- Load a new dictionary with personal wordlist

Description

int pspell_new_personal ( string personal, string language [, string spelling [, string jargon [, string encoding [, int mode]]]])

pspell_new_personal() opens up a new dictionary with a personal wordlist and returns the dictionary link identifier for use in other pspell functions. The wordlist can be modified and saved with pspell_save_wordlist(), if desired. However, the replacement pairs are not saved. In order to save replacement pairs, you should create a config using pspell_config_create(), set the personal wordlist file with pspell_config_personal(), set the file for replacement pairs with pspell_config_repl(), and open a new dictionary with pspell_new_config().

The personal parameter specifies the file where words added to the personal list will be stored. It should be an absolute filename beginning with '/' because otherwise it will be relative to $HOME, which is "/root" for most systems, and is probably not what you want.

The language parameter is the language code which consists of the two letter ISO 639 language code and an optional two letter ISO 3166 country code after a dash or underscore.

The spelling parameter is the requested spelling for languages with more than one spelling such as English. Known values are 'american', 'british', and 'canadian'.

The jargon parameter contains extra information to distinguish two different words lists that have the same language and spelling parameters.

The mode parameter is the mode in which spellchecker will work. There are several modes available:

PSPELL_FAST - Fast mode (least number of suggestions)
PSPELL_NORMAL - Normal mode (more suggestions)
PSPELL_BAD_SPELLERS - Slow mode (a lot of suggestions)
PSPELL_RUN_TOGETHER - Consider run-together words as legal compounds. That is, "thecat" will be a legal compound, athough there should be a space between the two words. Changing this setting only affects the results returned by pspell_check(); pspell_suggest() will still return suggestions.

Mode is a bitmask constructed from different constants listed above. However, PSPELL_FAST, PSPELL_NORMAL and PSPELL_BAD_SPELLERS are mutually exclusive, so you should select only one of them.

For more information and examples, check out inline manual pspell website:http://aspell.net/.

Příklad 1. pspell_new_personal()

$pspell_link = pspell_new_personal ("/var/dictionaries/custom.pws", "en", "", "", "", PSPELL_FAST|PSPELL_RUN_TOGETHER));

pspell_new

(PHP 4 >= 4.0.2)

pspell_new -- Load a new dictionary

Description

int pspell_new ( string language [, string spelling [, string jargon [, string encoding [, int mode]]]])

pspell_new() opens up a new dictionary and returns the dictionary link identifier for use in other pspell functions.

The language parameter is the language code which consists of the two letter ISO 639 language code and an optional two letter ISO 3166 country code after a dash or underscore.

The spelling parameter is the requested spelling for languages with more than one spelling such as English. Known values are 'american', 'british', and 'canadian'.

The jargon parameter contains extra information to distinguish two different words lists that have the same language and spelling parameters.

The mode parameter is the mode in which spellchecker will work. There are several modes available:

PSPELL_FAST - Fast mode (least number of suggestions)
PSPELL_NORMAL - Normal mode (more suggestions)
PSPELL_BAD_SPELLERS - Slow mode (a lot of suggestions)
PSPELL_RUN_TOGETHER - Consider run-together words as legal compounds. That is, "thecat" will be a legal compound, athough there should be a space between the two words. Changing this setting only affects the results returned by pspell_check(); pspell_suggest() will still return suggestions.

Mode is a bitmask constructed from different constants listed above. However, PSPELL_FAST, PSPELL_NORMAL and PSPELL_BAD_SPELLERS are mutually exclusive, so you should select only one of them.

For more information and examples, check out inline manual pspell website:http://aspell.net/.

Příklad 1. pspell_new()

$pspell_link = pspell_new ("en", "", "", "", (PSPELL_FAST|PSPELL_RUN_TOGETHER));

pspell_save_wordlist

(PHP 4 >= 4.0.2)

pspell_save_wordlist -- Save the personal wordlist to a file

Description

int pspell_save_wordlist ( int dictionary_link)

pspell_save_wordlist() saves the personal wordlist from the current session. The dictionary has to be open with pspell_new_personal(), and the location of files to be saved specified with pspell_config_personal() and (optionally) pspell_config_repl(). Please, note that this function will not work unless you have pspell .11.2 and aspell .32.5 or later.

Příklad 1. pspell_add_to_personal()

$pspell_config = pspell_config_create ("en"); pspell_config_personal ($pspell_config, "/tmp/dicts/newdict"); $pspell_link = pspell_new_config ($pspell_config); pspell_add_to_personal ($pspell_link, "Vlad"); pspell_save_wordlist ($pspell_link);

pspell_store_replacement

(PHP 4 >= 4.0.2)

pspell_store_replacement -- Store a replacement pair for a word

Description

int pspell_store_replacement ( int dictionary_link, string misspelled, string correct)

pspell_store_replacement() stores a replacement pair for a word, so that replacement can be returned by pspell_suggest() later. In order to be able to take advantage of this function, you have to use pspell_new_personal() to open the dictionary. In order to permanently save the replacement pair, you have to use pspell_config_personal() and pspell_config_repl() to set the path where to save your custom wordlists, and then use pspell_save_wordlist() for the changes to be written to disk. Please, note that this function will not work unless you have pspell .11.2 and aspell .32.5 or later.

Příklad 1. pspell_store_replacement()

$pspell_config = pspell_config_create ("en"); pspell_config_personal ($pspell_config, "/var/dictionaries/custom.pws"); pspell_config_repl ($pspell_config, "/var/dictionaries/custom.repl"); $pspell_link = pspell_new_config ($pspell_config); pspell_store_replacement ($pspell_link, $misspelled, $correct); pspell_save_wordlist ($pspell_link);

pspell_suggest

(PHP 4 >= 4.0.2)

pspell_suggest -- Suggest spellings of a word

Description

array pspell_suggest ( int dictionary_link, string word)

pspell_suggest() returns an array of possible spellings for the given word.

Příklad 1. pspell_suggest()

$pspell_link = pspell_new ("en"); if (!pspell_check ($pspell_link, "testt")) { $suggestions = pspell_suggest ($pspell_link, "testt"); foreach ($suggestions as $suggestion) { echo "Possible spelling: $suggestion<br>"; } }

LXXXV. GNU Readline

readline() funkce implementují rozhraní ke GNU Readline knihovně. Tyto funkce poskytují editovatelné příkazové řádky. Příkladem může být způsob, jakým vám Bash umožňuje vkládat znaky nebo listovat historií příkazů pomocí kláves pro pohyb kurzoru. Z interaktivní povahy této knihovny vyplývá, že není příliš užitečná pro psaní webových aplikací, ale může být užitečná při psaní skriptů, které se mají spouštět z příkazové řádky.

Domovskou stránkou GNU Readline projektu je http://cnswww.cns.cwru.edu/~chet/readline/rltop.html. Udržuje jej Chet Ramey, který je také autorem Bashe.

Obsah
readline_add_history -- Přidat řádek do historie
readline_clear_history -- Smazat historii
readline_completion_function -- Zaregistrovat dokončující funkci
readline_info -- Zjistit/nastavit různé interní proměnné readline
readline_list_history -- Vypsat historii
readline_read_history -- Vrátit historii
readline_write_history -- Zapsat historii
readline -- Přečíst řádek

Tato funkce vrátí jeden řádek od uživatele. Můžete specifikovat řetězec, který se má uživateli zobrazit jako výzva. Z vráceného řádku je odstraněna sekvence konce řádku. Do historie tento řádek musíte přidat sami pomocí readline_add_history().

Příklad 1. readline()

//ziska 3 prikazy uzivatele
for ($i=0; $i < 3; $i++) {
        $line = readline ("Command: ");
        readline_add_history ($line);
}

//vypise historii
print_r (readline_list_history());

//vypise promenne
print_r (readline_info());

LXXXVI. GNU Recode funkce

Tento modul obsahuje rozhraní ke GNU Recode knihovně, verze 3.5. Pokud cchete používat funkce definované v tomto modulu, musíte zkompilovat váš PHP interpretr s --with-recode. K tomu potřebujete mít na svém systému nainstalovanou GNU Recode 3.5 nebo vyšší.

GNU Recode knihovna konvertuje soubory mezi různými znakovými sadami a kódováními. Když nelze dosáhnout přesné konverze, může se uchýlit k approximacím. Tato knihovna rozeznává nebo produkuje téměř 150 různých znakových sad, a je schopná konvertovat soubory mezi téměř libovolným párem. Podporuje většinu znakových sad z RFC 1345.

Obsah
recode_file -- Překóduje soubor na soubor podle požadavku
recode_string -- Překóduje řetězec podle požadavku
recode -- Překóduje řetězec podle požadavku

recode_file

(PHP 3>= 3.0.13, PHP 4 )

recode_file -- Překóduje soubor na soubor podle požadavku

Popis

boolean recode_file ( string request, resource input, resource output)

Překóduje soubor odkazovaný deskriptorem input do souboru odkazovaném deskriptorem output podle požadavku request. Pokud se nepodařilo požadavek provést, vrací FALSE, jinak TRUE.

Tato funkce v současnosti nezpracovává deskriptory odkazující na vzdálené soubory (URL). Oba deskriptory musí ukazovat na místní soubory.

Příklad 1. Základní příklad recode_file()

$input = fopen ('input.txt', 'r'); $output = fopen ('output.txt', 'w'); recode_file ("us..flat", $input, $output);

recode_string

(PHP 3>= 3.0.13, PHP 4 )

recode_string -- Překóduje řetězec podle požadavku

Popis

string recode_string ( string request, string string)

Překóduje řetězec string podle požadavku request. Vrací překódovaný řetězec nebo FALSE, pokud nebylo možné provést požadavek na překódování.

Jednoduchý požadavek na překódování může být "lat1..iso646-de". Detailní instrukce k požadavkům viz GNU Recode dokumentaci u vaší instalace.

Příklad 1. Základní recode_string() příklad:

print recode_string ("us..flat", "Následující znak má diakritické znaménko: á");

recode

(PHP 4 )

recode -- Překóduje řetězec podle požadavku

Popis

string recode_string ( string request, string string)

Poznámka: Toto je alias k recode_string(). Byl přidán v PHP 4.

LXXXVII. Regular Expression Functions (Perl-Compatible)

The syntax for patterns used in these functions closely resembles Perl. The expression should be enclosed in the delimiters, a forward slash (/), for example. Any character can be used for delimiter as long as it's not alphanumeric or backslash (\). If the delimiter character has to be used in the expression itself, it needs to be escaped by backslash. Since PHP 4.0.4, you can also use Perl-style (), {}, [], and <> matching delimiters.

The ending delimiter may be followed by various modifiers that affect the matching. See Pattern Modifiers.

PHP also supports regular expressions using a POSIX-extended syntax using the POSIX-extended regex functions..

Requirements

Regular expression support is provided by the PCRE library package, which is open source software, written by Philip Hazel, and copyright by the University of Cambridge, England. It is available at ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/.

Installation

Beginning with PHP 4.2.0 this function are enabled by default. For older versions you have to configure and compile PHP with --with-pcre-regex[=DIR] in order to use these functions. You can disable the pcre functions with --without-pcre-regex.

Runtime Configuration

Toto rozšíření nemá definováno žádné konfigurační direktivy.

Resource types

Toto rezšíření nemá definován žádný typ prostředku (resource).

Predefined constants

Tabulka 1. PREG constants

constant	description
PREG_PATTERN_ORDER	Orders results so that $matches[0] is an array of full pattern matches, $matches[1] is an array of strings matched by the first parenthesized subpattern, and so on. This flag is only used with preg_match_all().
PREG_SET_ORDER	Orders results so that $matches[0] is an array of first set of matches, $matches[1] is an array of second set of matches, and so on. This flag is only used with preg_match_all().
PREG_OFFSET_CAPTURE	See the description of `PREG_SPLIT_OFFSET_CAPTURE`. This flag is available since `PHP` 4.3.0 .
PREG_SPLIT_NO_EMPTY	This flag tells preg_split() to only return only non-empty pieces.
PREG_SPLIT_DELIM_CAPTURE	This flag tells preg_split() to capture parenthesized expression in the delimiter pattern as well. This flag is available since `PHP` 4.0.5 .
PREG_SPLIT_OFFSET_CAPTURE	If this flag is set, for every occuring match the appendant string offset will also be returned. Note that this changes the return value in an array where very element is an array consisting of the matched string at offset 0 and it's string offset into subject at offset 1. This flag is available since `PHP` 4.3.0 and is only used for preg_split().

Examples

Příklad 1. Examples of valid patterns

/<\/\w+>/

|(\d{3})-\d+|Sm

/^(?i)php[34]/

{^\s+(\s+)?$}

Příklad 2. Examples of invalid patterns

/href='(.*)' - missing ending delimiter

/\w+\s*\w+/J - unknown modifier 'J'

1-\d3-\d3-\d4| - missing starting delimiter

Obsah
Pattern Modifiers -- Describes possible modifiers in regex patterns
Pattern Syntax -- Describes PCRE regex syntax
preg_grep -- Return array entries that match the pattern
preg_match_all -- Perform a global regular expression match
preg_match -- Perform a regular expression match
preg_quote -- Quote regular expression characters
preg_replace_callback -- Perform a regular expression search and replace using a callback
preg_replace -- Perform a regular expression search and replace
preg_split -- Split string by a regular expression

Pattern Modifiers

(unknown)

Pattern Modifiers -- Describes possible modifiers in regex patterns

Description

The current possible PCRE modifiers are listed below. The names in parentheses refer to internal PCRE names for these modifiers.

i (PCRE_CASELESS)

If this modifier is set, letters in the pattern match both upper and lower case letters.

m (PCRE_MULTILINE)

By default, PCRE treats the subject string as consisting of a single "line" of characters (even if it actually contains several newlines). The "start of line" metacharacter (^) matches only at the start of the string, while the "end of line" metacharacter ($) matches only at the end of the string, or before a terminating newline (unless D modifier is set). This is the same as Perl.

When this modifier is set, the "start of line" and "end of line" constructs match immediately following or immediately before any newline in the subject string, respectively, as well as at the very start and end. This is equivalent to Perl's /m modifier. If there are no "\n" characters in a subject string, or no occurrences of ^ or $ in a pattern, setting this modifier has no effect.

s (PCRE_DOTALL)

If this modifier is set, a dot metacharacter in the pattern matches all characters, including newlines. Without it, newlines are excluded. This modifier is equivalent to Perl's /s modifier. A negative class such as [^a] always matches a newline character, independent of the setting of this modifier.

x (PCRE_EXTENDED)

If this modifier is set, whitespace data characters in the pattern are totally ignored except when escaped or inside a character class, and characters between an unescaped # outside a character class and the next newline character, inclusive, are also ignored. This is equivalent to Perl's /x modifier, and makes it possible to include comments inside complicated patterns. Note, however, that this applies only to data characters. Whitespace characters may never appear within special character sequences in a pattern, for example within the sequence (?( which introduces a conditional subpattern.

e

If this modifier is set, preg_replace() does normal substitution of backreferences in the replacement string, evaluates it as PHP code, and uses the result for replacing the search string.

Only preg_replace() uses this modifier; it is ignored by other PCRE functions.

A (PCRE_ANCHORED)

If this modifier is set, the pattern is forced to be "anchored", that is, it is constrained to match only at the start of the string which is being searched (the "subject string"). This effect can also be achieved by appropriate constructs in the pattern itself, which is the only way to do it in Perl.

D (PCRE_DOLLAR_ENDONLY)

If this modifier is set, a dollar metacharacter in the pattern matches only at the end of the subject string. Without this modifier, a dollar also matches immediately before the final character if it is a newline (but not before any other newlines). This modifier is ignored if m modifier is set. There is no equivalent to this modifier in Perl.

S

When a pattern is going to be used several times, it is worth spending more time analyzing it in order to speed up the time taken for matching. If this modifier is set, then this extra analysis is performed. At present, studying a pattern is useful only for non-anchored patterns that do not have a single fixed starting character.

U (PCRE_UNGREEDY)

This modifier inverts the "greediness" of the quantifiers so that they are not greedy by default, but become greedy if followed by "?". It is not compatible with Perl. It can also be set by a (?U) modifier setting within the pattern.

X (PCRE_EXTRA)

This modifier turns on additional functionality of PCRE that is incompatible with Perl. Any backslash in a pattern that is followed by a letter that has no special meaning causes an error, thus reserving these combinations for future expansion. By default, as in Perl, a backslash followed by a letter with no special meaning is treated as a literal. There are at present no other features controlled by this modifier.

u (PCRE_UTF8)

This modifier turns on additional functionality of PCRE that is incompatible with Perl. Pattern strings are treated as UTF-8. This modifier is available from PHP 4.1.0 or greater.

Pattern Syntax

(unknown)

Pattern Syntax -- Describes PCRE regex syntax

Description

The PCRE library is a set of functions that implement regular expression pattern matching using the same syntax and semantics as Perl 5, with just a few differences (see below). The current implementation corresponds to Perl 5.005.

Differences From Perl

The differences described here are with respect to Perl 5.005.

By default, a whitespace character is any character that the C library function isspace() recognizes, though it is possible to compile PCRE with alternative character type tables. Normally isspace() matches space, formfeed, newline, carriage return, horizontal tab, and vertical tab. Perl 5 no longer includes vertical tab in its set of whitespace characters. The \v escape that was in the Perl documentation for a long time was never in fact recognized. However, the character itself was treated as whitespace at least up to 5.002. In 5.004 and 5.005 it does not match \s.
PCRE does not allow repeat quantifiers on lookahead assertions. Perl permits them, but they do not mean what you might think. For example, (?!a){3} does not assert that the next three characters are not "a". It just asserts that the next character is not "a" three times.
Capturing subpatterns that occur inside negative looka- head assertions are counted, but their entries in the offsets vector are never set. Perl sets its numerical vari- ables from any such patterns that are matched before the assertion fails to match something (thereby succeeding), but only if the negative lookahead assertion contains just one branch.
Though binary zero characters are supported in the subject string, they are not allowed in a pattern string because it is passed as a normal C string, terminated by zero. The escape sequence "\\x00" can be used in the pattern to represent a binary zero.
The following Perl escape sequences are not supported: \l, \u, \L, \U, \E, \Q. In fact these are implemented by Perl's general string-handling and are not part of its pat- tern matching engine.
The Perl \G assertion is not supported as it is not relevant to single pattern matches.
Fairly obviously, PCRE does not support the (?{code}) construction.
There are at the time of writing some oddities in Perl 5.005_02 concerned with the settings of captured strings when part of a pattern is repeated. For example, matching "aba" against the pattern /^(a(b)?)+$/ sets $2 to the value "b", but matching "aabbaa" against /^(aa(bb)?)+$/ leaves $2 unset. However, if the pattern is changed to /^(aa(b(b))?)+$/ then $2 (and $3) get set. In Perl 5.004 $2 is set in both cases, and that is also TRUE of PCRE. If in the future Perl changes to a consistent state that is different, PCRE may change to follow.
Another as yet unresolved discrepancy is that in Perl 5.005_02 the pattern /^(a)?(?(1)a|b)+$/ matches the string "a", whereas in PCRE it does not. However, in both Perl and PCRE /^(a)?a/ matched against "a" leaves $1 unset.
PCRE provides some extensions to the Perl regular expression facilities:
1. Although lookbehind assertions must match fixed length strings, each alternative branch of a lookbehind assertion can match a different length of string. Perl 5.005 requires them all to have the same length.
2. If PCRE_DOLLAR_ENDONLY is set and PCRE_MULTILINE is not set, the $ meta- character matches only at the very end of the string.
3. If PCRE_EXTRA is set, a backslash followed by a letter with no special meaning is faulted.
4. If PCRE_UNGREEDY is set, the greediness of the repeti- tion quantifiers is inverted, that is, by default they are not greedy, but if followed by a question mark they are.

Regular Expression Details

Introduction

The syntax and semantics of the regular expressions sup- ported by PCRE are described below. Regular expressions are also described in the Perl documentation and in a number of other books, some of which have copious examples. Jeffrey Friedl's "Mastering Regular Expressions", published by O'Reilly (ISBN 1-56592-257-3), covers them in great detail. The description here is intended as reference documentation. A regular expression is a pattern that is matched against a subject string from left to right. Most characters stand for themselves in a pattern, and match the corresponding charac- ters in the subject. As a trivial example, the pattern The quick brown fox matches a portion of a subject string that is identical to itself.

Meta-caracters

The power of regular expressions comes from the ability to include alternatives and repetitions in the pat- tern. These are encoded in the pattern by the use of meta- characters, which do not stand for themselves but instead are interpreted in some special way.

There are two different sets of meta-characters: those that are recognized anywhere in the pattern except within square brackets, and those that are recognized in square brackets. Outside square brackets, the meta-characters are as follows:

\: general escape character with several uses
^: assert start of subject (or line, in multiline mode)
$: assert end of subject (or line, in multiline mode)
.: match any character except newline (by default)
[: start character class definition
]: end character class definition
|: start of alternative branch
(: start subpattern
): end subpattern
?: extends the meaning of (, also 0 or 1 quantifier, also quantifier minimizer
*: 0 or more quantifier
+: 1 or more quantifier
{: start min/max quantifier
}: end min/max quantifier

Part of a pattern that is in square brackets is called a "character class". In a character class the only meta- characters are:

\: general escape character
^: negate the class, but only if the first character
-: indicates character range
]: terminates the character class

The following sections describe the use of each of the meta-characters.

backslash

The backslash character has several uses. Firstly, if it is followed by a non-alphameric character, it takes away any special meaning that character may have. This use of backslash as an escape character applies both inside and outside character classes.

For example, if you want to match a "*" character, you write "\*" in the pattern. This applies whether or not the follow- ing character would otherwise be interpreted as a meta- character, so it is always safe to precede a non-alphameric with "\" to specify that it stands for itself. In particu- lar, if you want to match a backslash, you write "\\".

If a pattern is compiled with the PCRE_EXTENDED option, whi- tespace in the pattern (other than in a character class) and characters between a "#" outside a character class and the next newline character are ignored. An escaping backslash can be used to include a whitespace or "#" character as part of the pattern.

A second use of backslash provides a way of encoding non- printing characters in patterns in a visible manner. There is no restriction on the appearance of non-printing charac- ters, apart from the binary zero that terminates a pattern, but when a pattern is being prepared by text editing, it is usually easier to use one of the following escape sequences than the binary character it represents:

\a: alarm, that is, the BEL character (hex 07)
\cx: "control-x", where x is any character
\e: escape (hex 1B)
\f: formfeed (hex 0C)
\n: newline (hex 0A)
\r: carriage return (hex 0D)
\t: tab (hex 09)
\xhh: character with hex code hh
\ddd: character with octal code ddd, or backreference

The precise effect of "\cx" is as follows: if "x" is a lower case letter, it is converted to upper case. Then bit 6 of the character (hex 40) is inverted. Thus "\cz" becomes hex 1A, but "\c{" becomes hex 3B, while "\c;" becomes hex 7B.

After "\x", up to two hexadecimal digits are read (letters can be in upper or lower case).

After "\0" up to two further octal digits are read. In both cases, if there are fewer than two digits, just those that are present are used. Thus the sequence "\0\x\07" specifies two binary zeros followed by a BEL character. Make sure you supply two digits after the initial zero if the character that follows is itself an octal digit.

The handling of a backslash followed by a digit other than 0 is complicated. Outside a character class, PCRE reads it and any following digits as a decimal number. If the number is less than 10, or if there have been at least that many previous capturing left parentheses in the expression, the entire sequence is taken as a back reference. A description of how this works is given later, following the discussion of parenthesized subpatterns.

Inside a character class, or if the decimal number is greater than 9 and there have not been that many capturing subpatterns, PCRE re-reads up to three octal digits follow- ing the backslash, and generates a single byte from the least significant 8 bits of the value. Any subsequent digits stand for themselves. For example:

\040: is another way of writing a space
\40: is the same, provided there are fewer than 40 previous capturing subpatterns
\7: is always a back reference
\11: might be a back reference, or another way of writing a tab
\011: is always a tab
\0113: is a tab followed by the character "3"
\113: is the character with octal code 113 (since there can be no more than 99 back references)
\377: is a byte consisting entirely of 1 bits
\81: is either a back reference, or a binary zero followed by the two characters "8" and "1"

Note that octal values of 100 or greater must not be intro- duced by a leading zero, because no more than three octal digits are ever read.

All the sequences that define a single byte value can be used both inside and outside character classes. In addition, inside a character class, the sequence "\b" is interpreted as the backspace character (hex 08). Outside a character class it has a different meaning (see below).

The third use of backslash is for specifying generic charac- ter types:

\d: any decimal digit
\D: any character that is not a decimal digit
\s: any whitespace character
\S: any character that is not a whitespace character
\w: any "word" character
\W: any "non-word" character

Each pair of escape sequences partitions the complete set of characters into two disjoint sets. Any given character matches one, and only one, of each pair.

A "word" character is any letter or digit or the underscore character, that is, any character which can be part of a Perl "word". The definition of letters and digits is controlled by PCRE's character tables, and may vary if locale-specific matching is taking place (see "Locale support" above). For example, in the "fr" (French) locale, some char- acter codes greater than 128 are used for accented letters, and these are matched by \w.

These character type sequences can appear both inside and outside character classes. They each match one character of the appropriate type. If the current matching point is at the end of the subject string, all of them fail, since there is no character to match.

The fourth use of backslash is for certain simple asser- tions. An assertion specifies a condition that has to be met at a particular point in a match, without consuming any characters from the subject string. The use of subpatterns for more complicated assertions is described below. The backslashed assertions are

\b: word boundary
\B: not a word boundary
\A: start of subject (independent of multiline mode)
\Z: end of subject or newline at end (independent of multiline mode)
\z: end of subject (independent of multiline mode)

These assertions may not appear in character classes (but note that "\b" has a different meaning, namely the backspace character, inside a character class).

A word boundary is a position in the subject string where the current character and the previous character do not both match \w or \W (i.e. one matches \w and the other matches \W), or the start or end of the string if the first or last character matches \w, respectively.

The \A, \Z, and \z assertions differ from the traditional circumflex and dollar (described below) in that they only ever match at the very start and end of the subject string, whatever options are set. They are not affected by the PCRE_NOTBOL or PCRE_NOTEOL options. The difference between \Z and \z is that \Z matches before a newline that is the last character of the string as well as at the end of the string, whereas \z matches only at the end.

Circumflex and dollar

     Outside a character class, in the default matching mode, the
     circumflex  character  is an assertion which is true only if
     the current matching point is at the start  of  the  subject
     string. Inside a character class, circumflex has an entirely
     different meaning (see below).

     Circumflex need not be the first character of the pattern if
     a  number of alternatives are involved, but it should be the
     first thing in each alternative in which it appears  if  the
     pattern is ever to match that branch. If all possible alter-
     natives start with a circumflex, that is, if the pattern  is
     constrained to match only at the start of the subject, it is
     said to be an "anchored" pattern. (There are also other con-
     structs that can cause a pattern to be anchored.)

     A dollar character is an assertion which is TRUE only if the
     current  matching point is at the end of the subject string,
     or immediately before a newline character that is  the  last
     character in the string (by default). Dollar need not be the
     last character of the pattern if a  number  of  alternatives
     are  involved,  but it should be the last item in any branch
     in which it appears.  Dollar has no  special  meaning  in  a
     character class.

     The meaning of dollar can be changed so that it matches only
     at   the   very   end   of   the   string,  by  setting  the
     PCRE_DOLLAR_ENDONLY  option at compile or matching time. This
     does not affect the \Z assertion.

     The meanings of the circumflex  and  dollar  characters  are
     changed  if  the  PCRE_MULTILINE  option is set. When this is
     the case,  they  match  immediately  after  and  immediately
     before an internal "\n" character, respectively, in addition
     to matching at the start and end of the subject string.  For
     example,  the  pattern  /^abc$/  matches  the subject string
     "def\nabc" in multiline  mode,  but  not  otherwise.  Conse-
     quently,  patterns  that  are  anchored  in single line mode
     because all branches start with "^" are not anchored in mul-
     tiline  mode.  The  PCRE_DOLLAR_ENDONLY  option is ignored if
     PCRE_MULTILINE  is set.

     Note that the sequences \A, \Z, and \z can be used to  match
     the  start  and end of the subject in both modes, and if all
     branches of a pattern start with \A is it  always  anchored,
     whether PCRE_MULTILINE  is set or not.

FULL STOP

     Outside a character class, a dot in the pattern matches  any
     one  character  in  the  subject,  including  a non-printing
     character, but not (by default) newline.  If the PCRE_DOTALL
     option  is  set,  then dots match newlines as well. The han-
     dling of dot is entirely independent of the handling of cir-
     cumflex  and  dollar,  the only relationship being that they
     both involve newline characters.  Dot has no special meaning
     in a character class.

Square brackets

     An opening square bracket introduces a character class, ter-
     minated  by  a  closing  square  bracket.  A  closing square
     bracket on its own is  not  special.  If  a  closing  square
     bracket  is  required as a member of the class, it should be
     the first data character in the class (after an initial cir-
     cumflex, if present) or escaped with a backslash.

     A character class matches a single character in the subject;
     the  character  must  be in the set of characters defined by
     the class, unless the first character in the class is a cir-
     cumflex,  in which case the subject character must not be in
     the set defined by the class. If a  circumflex  is  actually
     required  as  a  member  of  the class, ensure it is not the
     first character, or escape it with a backslash.

     For example, the character class [aeiou] matches  any  lower
     case vowel, while [^aeiou] matches any character that is not
     a lower case vowel. Note that a circumflex is  just  a  con-
     venient  notation for specifying the characters which are in
     the class by enumerating those that are not. It  is  not  an
     assertion:  it  still  consumes a character from the subject
     string, and fails if the current pointer is at  the  end  of
     the string.

     When caseless matching  is  set,  any  letters  in  a  class
     represent  both their upper case and lower case versions, so
     for example, a caseless [aeiou] matches "A" as well as  "a",
     and  a caseless [^aeiou] does not match "A", whereas a case-
     ful version would.

     The newline character is never treated in any special way in
     character  classes,  whatever the setting of the PCRE_DOTALL
     or PCRE_MULTILINE  options is. A  class  such  as  [^a]  will
     always match a newline.

     The minus (hyphen) character can be used to specify a  range
     of  characters  in  a  character  class.  For example, [d-m]
     matches any letter between d and m, inclusive.  If  a  minus
     character  is required in a class, it must be escaped with a
     backslash or appear in a position where it cannot be  inter-
     preted as indicating a range, typically as the first or last
     character in the class.

     It is not possible to have the literal character "]" as  the
     end  character  of  a  range.  A  pattern such as [W-]46] is
     interpreted as a class of two characters ("W" and "-")  fol-
     lowed by a literal string "46]", so it would match "W46]" or
     "-46]". However, if the "]" is escaped with a  backslash  it
     is  interpreted  as  the end of range, so [W-\]46] is inter-
     preted as a single class containing a range followed by  two
     separate characters. The octal or hexadecimal representation
     of "]" can also be used to end a range.

     Ranges operate in ASCII collating sequence. They can also be
     used  for  characters  specified  numerically,  for  example
     [\000-\037]. If a range that includes letters is  used  when
     caseless  matching  is set, it matches the letters in either
     case. For example, [W-c] is equivalent  to  [][\^_`wxyzabc],
     matched  caselessly,  and  if  character tables for the "fr"
     locale are in use, [\xc8-\xcb] matches accented E characters
     in both cases.

     The character types \d, \D, \s, \S,  \w,  and  \W  may  also
     appear  in  a  character  class, and add the characters that
     they match to the class. For example, [\dABCDEF] matches any
     hexadecimal  digit.  A  circumflex  can conveniently be used
     with the upper case character types to specify a  more  res-
     tricted set of characters than the matching lower case type.
     For example, the class [^\W_] matches any letter  or  digit,
     but not underscore.

     All non-alphameric characters other than \,  -,  ^  (at  the
     start)  and  the  terminating ] are non-special in character
     classes, but it does no harm if they are escaped.

Vertical bar

     Vertical bar characters are  used  to  separate  alternative
     patterns. For example, the pattern

       gilbert|sullivan

     matches either "gilbert" or "sullivan". Any number of alter-
     natives  may  appear,  and an empty alternative is permitted
     (matching the empty string).   The  matching  process  tries
     each  alternative in turn, from left to right, and the first
     one that succeeds is used. If the alternatives are within  a
     subpattern  (defined  below),  "succeeds" means matching the
     rest of the main pattern as well as the alternative  in  the
     subpattern.

Internal option setting

     The settings of PCRE_CASELESS ,
     PCRE_MULTILINE ,
     PCRE_DOTALL ,
     and  PCRE_EXTENDED  can be changed from within the pattern by
     a sequence of Perl option letters enclosed between "(?"  and
     ")". The option letters are

       i  for PCRE_CASELESS
       m  for PCRE_MULTILINE
       s  for PCRE_DOTALL
       x  for PCRE_EXTENDED

     For example, (?im) sets caseless, multiline matching. It  is
     also possible to unset these options by preceding the letter
     with a hyphen, and a combined setting and unsetting such  as
     (?im-sx),  which sets PCRE_CASELESS  and PCRE_MULTILINE  while
     unsetting PCRE_DOTALL  and PCRE_EXTENDED , is also  permitted.
     If  a  letter  appears both before and after the hyphen, the
     option is unset.

     The scope of these option changes depends on  where  in  the
     pattern  the  setting  occurs. For settings that are outside
     any subpattern (defined below), the effect is the same as if
     the  options were set or unset at the start of matching. The
     following patterns all behave in exactly the same way:

       (?i)abc
       a(?i)bc
       ab(?i)c
       abc(?i)

     which in turn is the same as compiling the pattern abc  with
     PCRE_CASELESS   set.   In  other words, such "top level" set-
     tings apply to the whole pattern  (unless  there  are  other
     changes  inside subpatterns). If there is more than one set-
     ting of the same option at top level, the rightmost  setting
     is used.

     If an option change occurs inside a subpattern,  the  effect
     is  different.  This is a change of behaviour in Perl 5.005.
     An option change inside a subpattern affects only that  part
     of the subpattern that follows it, so

       (a(?i)b)c

     matches  abc  and  aBc  and  no  other   strings   (assuming
     PCRE_CASELESS   is  not used).  By this means, options can be
     made to have different settings in different  parts  of  the
     pattern.  Any  changes  made  in one alternative do carry on
     into subsequent branches within  the  same  subpattern.  For
     example,

       (a(?i)b|c)

     matches "ab", "aB", "c", and "C", even though when  matching
     "C" the first branch is abandoned before the option setting.
     This is because the effects of  option  settings  happen  at
     compile  time. There would be some very weird behaviour oth-
     erwise.

     The PCRE-specific options PCRE_UNGREEDY  and
     PCRE_EXTRA   can
     be changed in the same way as the Perl-compatible options by
     using the characters U and X  respectively.  The  (?X)  flag
     setting  is  special in that it must always occur earlier in
     the pattern than any of the additional features it turns on,
     even when it is at top level. It is best put at the start.

subpatterns

     Subpatterns are delimited by parentheses  (round  brackets),
     which can be nested.  Marking part of a pattern as a subpat-
     tern does two things:

     1. It localizes a set of alternatives. For example, the pat-
     tern

       cat(aract|erpillar|)

     matches one of the words "cat",  "cataract",  or  "caterpil-
     lar".  Without  the  parentheses, it would match "cataract",
     "erpillar" or the empty string.

     2. It sets up the subpattern as a capturing  subpattern  (as
     defined  above).   When the whole pattern matches, that por-
     tion of the subject string that matched  the  subpattern  is
     passed  back  to  the  caller  via  the  ovector argument of
     pcre_exec(). Opening parentheses are counted  from  left  to
     right (starting from 1) to obtain the numbers of the captur-
     ing subpatterns.

     For example, if the string "the red king" is matched against
     the pattern

       the ((red|white) (king|queen))

     the captured substrings are "red king", "red",  and  "king",
     and are numbered 1, 2, and 3.

     The fact that plain parentheses fulfil two functions is  not
     always  helpful.  There are often times when a grouping sub-
     pattern is required without a capturing requirement.  If  an
     opening parenthesis is followed by "?:", the subpattern does
     not do any capturing, and is not counted when computing  the
     number of any subsequent capturing subpatterns. For example,
     if the string "the  white  queen"  is  matched  against  the
     pattern

       the ((?:red|white) (king|queen))

     the captured substrings are "white queen" and  "queen",  and
     are  numbered  1  and 2. The maximum number of captured sub-
     strings is 99, and the maximum number  of  all  subpatterns,
     both capturing and non-capturing, is 200.

     As a  convenient  shorthand,  if  any  option  settings  are
     required  at  the  start  of a non-capturing subpattern, the
     option letters may appear between the "?" and the ":".  Thus
     the two patterns

       (?i:saturday|sunday)
       (?:(?i)saturday|sunday)

     match exactly the same set of strings.  Because  alternative
     branches  are  tried from left to right, and options are not
     reset until the end of the subpattern is reached, an  option
     setting  in  one  branch does affect subsequent branches, so
     the above patterns match "SUNDAY" as well as "Saturday".

Repetition

     Repetition is specified by quantifiers, which can follow any
     of the following items:

       a single character, possibly escaped
       the . metacharacter
       a character class
       a back reference (see next section)
       a parenthesized subpattern (unless it is  an  assertion  -
     see below)

     The general repetition quantifier specifies  a  minimum  and
     maximum  number  of  permitted  matches,  by  giving the two
     numbers in curly brackets (braces), separated  by  a  comma.
     The  numbers  must be less than 65536, and the first must be
     less than or equal to the second. For example:

       z{2,4}

     matches "zz", "zzz", or "zzzz". A closing brace on  its  own
     is not a special character. If the second number is omitted,
     but the comma is present, there is no upper  limit;  if  the
     second number and the comma are both omitted, the quantifier
     specifies an exact number of required matches. Thus

       [aeiou]{3,}

     matches at least 3 successive vowels,  but  may  match  many
     more, while

       \d{8}

     matches exactly 8 digits.  An  opening  curly  bracket  that
     appears  in a position where a quantifier is not allowed, or
     one that does not match the syntax of a quantifier, is taken
     as  a literal character. For example, {,6} is not a quantif-
     ier, but a literal string of four characters.

     The quantifier {0} is permitted, causing the  expression  to
     behave  as  if the previous item and the quantifier were not
     present.

     For convenience (and  historical  compatibility)  the  three
     most common quantifiers have single-character abbreviations:

       *    is equivalent to {0,}
       +    is equivalent to {1,}
       ?    is equivalent to {0,1}

     It is possible to construct infinite loops  by  following  a
     subpattern  that  can  match no characters with a quantifier
     that has no upper limit, for example:

       (a?)*

     Earlier versions of Perl and PCRE used to give an  error  at
     compile  time  for such patterns. However, because there are
     cases where this  can  be  useful,  such  patterns  are  now
     accepted,  but  if  any repetition of the subpattern does in
     fact match no characters, the loop is forcibly broken.

     By default, the quantifiers  are  "greedy",  that  is,  they
     match  as much as possible (up to the maximum number of per-
     mitted times), without causing the rest of  the  pattern  to
     fail. The classic example of where this gives problems is in
     trying to match comments in C programs. These appear between
     the  sequences /* and */ and within the sequence, individual
     * and / characters may appear. An attempt to  match  C  com-
     ments by applying the pattern

       /\*.*\*/

     to the string

       /* first command */  not comment  /* second comment */

     fails, because it matches  the  entire  string  due  to  the
     greediness of the .*  item.

     However, if a quantifier is followed  by  a  question  mark,
     then it ceases to be greedy, and instead matches the minimum
     number of times possible, so the pattern

       /\*.*?\*/

     does the right thing with the C comments. The meaning of the
     various  quantifiers is not otherwise changed, just the pre-
     ferred number of matches.  Do not confuse this use of  ques-
     tion  mark  with  its  use as a quantifier in its own right.
     Because it has two uses, it can sometimes appear doubled, as
     in

       \d??\d

     which matches one digit by preference, but can match two  if
     that is the only way the rest of the pattern matches.

     If the PCRE_UNGREEDY  option is set (an option which  is  not
     available  in  Perl)  then the quantifiers are not greedy by
     default, but individual ones can be made greedy by following
     them  with  a  question mark. In other words, it inverts the
     default behaviour.

     When a parenthesized subpattern is quantified with a minimum
     repeat  count  that is greater than 1 or with a limited max-
     imum, more store is required for the  compiled  pattern,  in
     proportion to the size of the minimum or maximum.

     If a pattern starts with .* or  .{0,}  and  the  PCRE_DOTALL
     option (equivalent to Perl's /s) is set, thus allowing the .
     to match newlines, then the pattern is implicitly  anchored,
     because whatever follows will be tried against every charac-
     ter position in the subject string, so there is no point  in
     retrying  the overall match at any position after the first.
     PCRE treats such a pattern as though it were preceded by \A.
     In  cases where it is known that the subject string contains
     no newlines, it is worth setting PCRE_DOTALL  when  the  pat-
     tern begins with .* in order to obtain this optimization, or
     alternatively using ^ to indicate anchoring explicitly.

     When a capturing subpattern is repeated, the value  captured
     is the substring that matched the final iteration. For exam-
     ple, after

       (tweedle[dume]{3}\s*)+

     has matched "tweedledum tweedledee" the value  of  the  cap-
     tured  substring  is  "tweedledee".  However,  if  there are
     nested capturing  subpatterns,  the  corresponding  captured
     values  may  have been set in previous iterations. For exam-
     ple, after

       /(a|(b))+/

     matches "aba" the value of the second captured substring  is
     "b".

BACK REFERENCES

     Outside a character class, a backslash followed by  a  digit
     greater  than  0  (and  possibly  further  digits) is a back
     reference to a capturing subpattern  earlier  (i.e.  to  its
     left)  in  the  pattern,  provided there have been that many
     previous capturing left parentheses.

     However, if the decimal number following  the  backslash  is
     less  than  10,  it is always taken as a back reference, and
     causes an error only if there are not  that  many  capturing
     left  parentheses in the entire pattern. In other words, the
     parentheses that are referenced need not be to the  left  of
     the  reference  for  numbers  less  than 10. See the section
     entitled "Backslash" above for further details of  the  han-
     dling of digits following a backslash.

     A back reference matches whatever actually matched the  cap-
     turing subpattern in the current subject string, rather than
     anything matching the subpattern itself. So the pattern

       (sens|respons)e and \1ibility

     matches "sense and sensibility" and "response and  responsi-
     bility",  but  not  "sense  and  responsibility". If caseful
     matching is in force at the time of the back reference, then
     the case of letters is relevant. For example,

       ((?i)rah)\s+\1

     matches "rah rah" and "RAH RAH", but  not  "RAH  rah",  even
     though  the  original  capturing subpattern is matched case-
     lessly.

     There may be more than one back reference to the  same  sub-
     pattern.  If  a  subpattern  has not actually been used in a
     particular match, then any  back  references  to  it  always
     fail. For example, the pattern

       (a|(bc))\2

     always fails if it starts to match  "a"  rather  than  "bc".
     Because  there  may  be up to 99 back references, all digits
     following the backslash are taken as  part  of  a  potential
     back reference number. If the pattern continues with a digit
     character, then some delimiter must be used to terminate the
     back reference. If the PCRE_EXTENDED  option is set, this can
     be whitespace.  Otherwise an empty comment can be used.

     A back reference that occurs inside the parentheses to which
     it  refers  fails when the subpattern is first used, so, for
     example, (a\1) never matches.  However, such references  can
     be useful inside repeated subpatterns. For example, the pat-
     tern

       (a|b\1)+

     matches any number of "a"s and also "aba", "ababaa" etc.  At
     each iteration of the subpattern, the back reference matches
     the character string corresponding to  the  previous  itera-
     tion.  In  order  for this to work, the pattern must be such
     that the first iteration does not need  to  match  the  back
     reference.  This  can  be  done using alternation, as in the
     example above, or by a quantifier with a minimum of zero.

Assertions

     An assertion is  a  test  on  the  characters  following  or
     preceding  the current matching point that does not actually
     consume any characters. The simple assertions coded  as  \b,
     \B,  \A,  \Z,  \z, ^ and $ are described above. More compli-
     cated assertions are coded as  subpatterns.  There  are  two
     kinds:  those that look ahead of the current position in the
     subject string, and those that look behind it.

     An assertion subpattern is matched in the normal way, except
     that  it  does not cause the current matching position to be
     changed. Lookahead assertions start with  (?=  for  positive
     assertions and (?! for negative assertions. For example,

       \w+(?=;)

     matches a word followed by a semicolon, but does not include
     the semicolon in the match, and

       foo(?!bar)

     matches any occurrence of "foo"  that  is  not  followed  by
     "bar". Note that the apparently similar pattern

       (?!foo)bar

     does not find an occurrence of "bar"  that  is  preceded  by
     something other than "foo"; it finds any occurrence of "bar"
     whatsoever, because the assertion  (?!foo)  is  always  TRUE
     when  the  next  three  characters  are  "bar". A lookbehind
     assertion is needed to achieve this effect.

     Lookbehind assertions start with (?<=  for  positive  asser-
     tions and (?<! for negative assertions. For example,

       (?<!foo)bar

     does find an occurrence of "bar" that  is  not  preceded  by
     "foo". The contents of a lookbehind assertion are restricted
     such that all the strings  it  matches  must  have  a  fixed
     length.  However, if there are several alternatives, they do
     not all have to have the same fixed length. Thus

       (?<=bullock|donkey)

     is permitted, but

       (?<!dogs?|cats?)

     causes an error at compile time. Branches  that  match  dif-
     ferent length strings are permitted only at the top level of
     a lookbehind assertion. This is an extension  compared  with
     Perl  5.005,  which  requires all branches to match the same
     length of string. An assertion such as

       (?<=ab(c|de))

     is not permitted, because its single  top-level  branch  can
     match two different lengths, but it is acceptable if rewrit-
     ten to use two top-level branches:

       (?<=abc|abde)

     The implementation of lookbehind  assertions  is,  for  each
     alternative,  to  temporarily move the current position back
     by the fixed width and then  try  to  match.  If  there  are
     insufficient  characters  before  the  current position, the
     match is deemed to fail.  Lookbehinds  in  conjunction  with
     once-only  subpatterns can be particularly useful for match-
     ing at the ends of strings; an example is given at  the  end
     of the section on once-only subpatterns.

     Several assertions (of any sort) may  occur  in  succession.
     For example,

       (?<=\d{3})(?<!999)foo

     matches "foo" preceded by three digits that are  not  "999".
     Notice  that each of the assertions is applied independently
     at the same point in the subject string. First  there  is  a
     check  that  the  previous  three characters are all digits,
     then there is a check that the same three characters are not
     "999".   This  pattern  does not match "foo" preceded by six
     characters, the first of which are digits and the last three
     of  which  are  not  "999".  For  example,  it doesn't match
     "123abcfoo". A pattern to do that is

       (?<=\d{3}...)(?<!999)foo

     This time the first assertion looks  at  the  preceding  six
     characters,  checking  that  the first three are digits, and
     then the second assertion checks that  the  preceding  three
     characters are not "999".

     Assertions can be nested in any combination. For example,

       (?<=(?<!foo)bar)baz

     matches an occurrence of "baz" that  is  preceded  by  "bar"
     which in turn is not preceded by "foo", while

       (?<=\d{3}(?!999)...)foo

     is another pattern which matches  "foo"  preceded  by  three
     digits and any three characters that are not "999".

     Assertion subpatterns are not capturing subpatterns, and may
     not  be  repeated,  because  it makes no sense to assert the
     same thing several times. If any kind of assertion  contains
     capturing  subpatterns  within it, these are counted for the
     purposes of numbering the capturing subpatterns in the whole
     pattern.   However,  substring capturing is carried out only
     for positive assertions, because it does not make sense  for
     negative assertions.

     Assertions count towards the maximum  of  200  parenthesized
     subpatterns.

Once-only subpatterns

     With both maximizing and minimizing repetition,  failure  of
     what  follows  normally  causes  the repeated item to be re-
     evaluated to see if a different number of repeats allows the
     rest  of  the  pattern  to  match. Sometimes it is useful to
     prevent this, either to change the nature of the  match,  or
     to  cause  it fail earlier than it otherwise might, when the
     author of the pattern knows there is no  point  in  carrying
     on.

     Consider, for example, the pattern \d+foo  when  applied  to
     the subject line

       123456bar

     After matching all 6 digits and then failing to match "foo",
     the normal action of the matcher is to try again with only 5
     digits matching the \d+ item, and then with 4,  and  so  on,
     before ultimately failing. Once-only subpatterns provide the
     means for specifying that once a portion of the pattern  has
     matched,  it  is  not to be re-evaluated in this way, so the
     matcher would give up immediately on failing to match  "foo"
     the  first  time.  The  notation  is another kind of special
     parenthesis, starting with (?> as in this example:

       (?>\d+)bar

     This kind of parenthesis "locks up" the  part of the pattern
     it  contains once it has matched, and a failure further into
     the pattern is prevented from backtracking  into  it.  Back-
     tracking  past  it to previous items, however, works as nor-
     mal.

     An alternative description is that a subpattern of this type
     matches  the  string  of  characters that an identical stan-
     dalone pattern would match, if anchored at the current point
     in the subject string.

     Once-only subpatterns are not capturing subpatterns.  Simple
     cases  such as the above example can be thought of as a max-
     imizing repeat that must  swallow  everything  it  can.  So,
     while both \d+ and \d+? are prepared to adjust the number of
     digits they match in order to make the rest of  the  pattern
     match, (?>\d+) can only match an entire sequence of digits.

     This construction can of course contain arbitrarily  compli-
     cated subpatterns, and it can be nested.

     Once-only subpatterns can be used in conjunction with  look-
     behind  assertions  to specify efficient matching at the end
     of the subject string. Consider a simple pattern such as

       abcd$

     when applied to a long string which does not match.  Because
     matching  proceeds  from  left  to right, PCRE will look for
     each "a" in the subject and then see if what follows matches
     the rest of the pattern. If the pattern is specified as

       ^.*abcd$

     then the initial .* matches the entire string at first,  but
     when  this  fails  (because  there  is no following "a"), it
     backtracks to match all but the last character, then all but
     the  last  two  characters, and so on. Once again the search
     for "a" covers the entire string, from right to left, so  we
     are no better off. However, if the pattern is written as

       ^(?>.*)(?<=abcd)

     then there can be no backtracking for the .*  item;  it  can
     match  only  the  entire  string.  The subsequent lookbehind
     assertion does a single test on the last four characters. If
     it  fails,  the  match  fails immediately. For long strings,
     this approach makes a significant difference to the process-
     ing time.

     When a pattern contains an unlimited repeat inside a subpat-
     tern  that  can  itself  be  repeated an unlimited number of
     times, the use of a once-only subpattern is the only way  to
     avoid  some  failing matches taking a very long time indeed.
     The pattern

       (\D+|<\d+>)*[!?]

     matches an unlimited number of substrings that  either  con-
     sist  of  non-digits,  or digits enclosed in <>, followed by
     either ! or ?. When it matches, it runs quickly. However, if
     it is applied to

       aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa

     it takes a long  time  before  reporting  failure.  This  is
     because the string can be divided between the two repeats in
     a large number of ways, and all have to be tried. (The exam-
     ple  used  [!?]  rather  than a single character at the end,
     because both PCRE and Perl have an optimization that  allows
     for  fast  failure  when  a  single  character is used. They
     remember the last single character that is  required  for  a
     match,  and  fail early if it is not present in the string.)
     If the pattern is changed to

       ((?>\D+)|<\d+>)*[!?]

     sequences of non-digits cannot be broken, and  failure  hap-
     pens quickly.

Conditional subpatterns

     It is possible to cause the matching process to obey a  sub-
     pattern  conditionally  or to choose between two alternative
     subpatterns, depending on the result  of  an  assertion,  or
     whether  a previous capturing subpattern matched or not. The
     two possible forms of conditional subpattern are

       (?(condition)yes-pattern)
       (?(condition)yes-pattern|no-pattern)

     If the condition is satisfied, the yes-pattern is used; oth-
     erwise  the  no-pattern  (if  present) is used. If there are
     more than two alternatives in the subpattern, a compile-time
     error occurs.

     There are two kinds of condition. If the  text  between  the
     parentheses  consists  of  a  sequence  of  digits, then the
     condition is satisfied if the capturing subpattern  of  that
     number  has  previously matched. Consider the following pat-
     tern, which contains non-significant white space to make  it
     more  readable  (assume  the  PCRE_EXTENDED   option)  and to
     divide it into three parts for ease of discussion:

       ( $ )?    [^()]+    (?(1) $ )

     The first part matches an optional opening parenthesis,  and
     if  that character is present, sets it as the first captured
     substring. The second part matches one  or  more  characters
     that  are  not  parentheses. The third part is a conditional
     subpattern that tests whether the first set  of  parentheses
     matched  or  not.  If  they did, that is, if subject started
     with an opening parenthesis, the condition is TRUE,  and  so
     the  yes-pattern  is  executed  and a closing parenthesis is
     required. Otherwise, since no-pattern is  not  present,  the
     subpattern  matches  nothing.  In  other words, this pattern
     matches a sequence of non-parentheses,  optionally  enclosed
     in parentheses.

     If the condition is not a sequence of digits, it must be  an
     assertion.  This  may be a positive or negative lookahead or
     lookbehind assertion. Consider this pattern, again  contain-
     ing  non-significant  white space, and with the two alterna-
     tives on the second line:

       (?(?=[^a-z]*[a-z])
       \d{2}-[a-z]{3}-\d{2}  |  \d{2}-\d{2}-\d{2} )

     The condition is a positive lookahead assertion that matches
     an optional sequence of non-letters followed by a letter. In
     other words, it tests for  the  presence  of  at  least  one
     letter  in the subject. If a letter is found, the subject is
     matched against  the  first  alternative;  otherwise  it  is
     matched  against the second. This pattern matches strings in
     one of the two forms dd-aaa-dd or dd-dd-dd,  where  aaa  are
     letters and dd are digits.

Comments

     The  sequence  (?#  marks  the  start  of  a  comment  which
     continues   up  to  the  next  closing  parenthesis.  Nested
     parentheses are not permitted. The characters that make up a
     comment play no part in the pattern matching at all.

     If the PCRE_EXTENDED  option is set, an unescaped # character
     outside  a character class introduces a comment that contin-
     ues up to the next newline character in the pattern.

Recursive patterns

     Consider the problem of matching a  string  in  parentheses,
     allowing  for  unlimited nested parentheses. Without the use
     of recursion, the best that can be done is to use a  pattern
     that  matches  up  to some fixed depth of nesting. It is not
     possible to handle an arbitrary nesting depth. Perl 5.6  has
     provided   an  experimental  facility  that  allows  regular
     expressions to recurse (amongst other things).  The  special
     item (?R) is  provided for  the specific  case of recursion.
     This PCRE  pattern  solves the  parentheses  problem (assume
     the PCRE_EXTENDED  option is set so that white space is
     ignored):

       $ ( (?>[^()]+) | (?R) )* $

     First it matches an opening parenthesis. Then it matches any
     number  of substrings which can either be a sequence of non-
     parentheses, or a recursive  match  of  the  pattern  itself
     (i.e. a correctly parenthesized substring). Finally there is
     a closing parenthesis.

     This particular example pattern  contains  nested  unlimited
     repeats, and so the use of a once-only subpattern for match-
     ing strings of non-parentheses is  important  when  applying
     the  pattern to strings that do not match. For example, when
     it is applied to

       (aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa()

     it yields "no match" quickly. However, if a  once-only  sub-
     pattern  is  not  used,  the match runs for a very long time
     indeed because there are so many different ways the + and  *
     repeats  can carve up the subject, and all have to be tested
     before failure can be reported.

     The values set for any capturing subpatterns are those  from
     the outermost level of the recursion at which the subpattern
     value is set. If the pattern above is matched against

       (ab(cd)ef)

     the value for the capturing parentheses is  "ef",  which  is
     the  last  value  taken  on  at the top level. If additional
     parentheses are added, giving

       $ ( ( (?>[^()]+) | (?R) )* ) $
          ^                        ^
          ^                        ^ then the string they capture
     is "ab(cd)ef", the contents of the top level parentheses. If
     there are more than 15 capturing parentheses in  a  pattern,
     PCRE  has  to  obtain  extra  memory  to store data during a
     recursion, which it does by using  pcre_malloc,  freeing  it
     via  pcre_free  afterwards. If no memory can be obtained, it
     saves data for the first 15 capturing parentheses  only,  as
     there is no way to give an out-of-memory error from within a
     recursion.

Performances

     Certain items that may appear in patterns are more efficient
     than  others.  It is more efficient to use a character class
     like [aeiou] than a set of alternatives such as (a|e|i|o|u).
     In  general,  the  simplest  construction  that provides the
     required behaviour is usually the  most  efficient.  Jeffrey
     Friedl's  book contains a lot of discussion about optimizing
     regular expressions for efficient performance.

     When a pattern begins with .* and the PCRE_DOTALL  option  is
     set,  the  pattern  is implicitly anchored by PCRE, since it
     can match only at the start of a subject string. However, if
     PCRE_DOTALL   is not set, PCRE cannot make this optimization,
     because the . metacharacter does not then match  a  newline,
     and if the subject string contains newlines, the pattern may
     match from the character immediately following one  of  them
     instead of from the very start. For example, the pattern

       (.*) second

     matches the subject "first\nand second" (where \n stands for
     a newline character) with the first captured substring being
     "and". In order to do this, PCRE  has  to  retry  the  match
     starting after every newline in the subject.

     If you are using such a pattern with subject strings that do
     not  contain  newlines,  the best performance is obtained by
     setting PCRE_DOTALL , or starting the  pattern  with  ^.*  to
     indicate  explicit anchoring. That saves PCRE from having to
     scan along the subject looking for a newline to restart at.

     Beware of patterns that contain nested  indefinite  repeats.
     These  can  take a long time to run when applied to a string
     that does not match. Consider the pattern fragment

       (a+)*

     This can match "aaaa" in 33 different ways, and this  number
     increases  very  rapidly  as  the string gets longer. (The *
     repeat can match 0, 1, 2, 3, or 4 times,  and  for  each  of
     those  cases other than 0, the + repeats can match different
     numbers of times.) When the remainder of the pattern is such
     that  the entire match is going to fail, PCRE has in princi-
     ple to try every possible variation, and this  can  take  an
     extremely long time.

     An optimization catches some of the more simple  cases  such
     as

       (a+)*b

     where a literal character follows. Before embarking  on  the
     standard matching procedure, PCRE checks that there is a "b"
     later in the subject string, and if there is not,  it  fails
     the  match  immediately. However, when there is no following
     literal this optimization cannot be used. You  can  see  the
     difference by comparing the behaviour of

       (a+)*\d

     with the pattern above. The former gives  a  failure  almost
     instantly  when  applied  to a whole line of "a" characters,
     whereas the latter takes an appreciable  time  with  strings
     longer than about 20 characters.

preg_grep

(PHP 4 )

preg_grep -- Return array entries that match the pattern

Description

array preg_grep ( string pattern, array input)

preg_grep() returns the array consisting of the elements of the input array that match the given pattern.

Since PHP 4.0.4, the results returned by preg_grep() are indexed using the keys from the input array. If this behavior is undesirable, use array_values() on the array returned by preg_grep() to reindex the values.

Příklad 1. preg_grep() example

// return all array elements // containing floating point numbers $fl_array = preg_grep ("/^(\d+)?\.\d+$/", $array);

preg_match_all

(PHP 3>= 3.0.9, PHP 4 )

preg_match_all -- Perform a global regular expression match

Description

int preg_match_all ( string pattern, string subject, array matches [, int flags])

Searches subject for all matches to the regular expression given in pattern and puts them in matches in the order specified by order.

After the first match is found, the subsequent searches are continued on from end of the last match.

flags can be a combination of the following flags (note that it doesn't make sense to use PREG_PATTERN_ORDER together with PREG_SET_ORDER):

PREG_PATTERN_ORDER

Orders results so that $matches[0] is an array of full pattern matches, $matches[1] is an array of strings matched by the first parenthesized subpattern, and so on.

preg_match_all ("|<[^>]+>(.*)</[^>]+>|U", 
    "<b>example: </b><div align=left>this is a test</div>", 
    $out, PREG_PATTERN_ORDER);
print $out[0][0].", ".$out[0][1]."\n";
print $out[1][0].", ".$out[1][1]."\n";

This example will produce:

<b>example: </b>, <div align=left>this is a test</div> example: , this is a test
So, $out[0] contains array of strings that matched full pattern, and $out[1] contains array of strings enclosed by tags.

PREG_SET_ORDER

Orders results so that $matches[0] is an array of first set of matches, $matches[1] is an array of second set of matches, and so on.

preg_match_all ("|<[^>]+>(.*)</[^>]+>|U", 
    "<b>example: </b><div align=left>this is a test</div>", 
    $out, PREG_SET_ORDER);
print $out[0][0].", ".$out[0][1]."\n";
print $out[1][0].", ".$out[1][1]."\n";

This example will produce:

<b>example: </b>, example: 
<div align=left>this is a test</div>, this is a test

In this case, $matches[0] is the first set of matches, and $matches[0][0] has text matched by full pattern, $matches[0][1] has text matched by first subpattern and so on. Similarly, $matches[1] is the second set of matches, etc.

PREG_OFFSET_CAPTURE

If this flag is set, for every occuring match the appendant string offset will also be returned. Note that this changes the return value in an array where every element is an array consisting of the matched string at offset 0 and it's string offset into subject at offset 1. This flag is available since PHP 4.3.0 .

If no order flag is given, PREG_PATTERN_ORDER is assumed.

Returns the number of full pattern matches (which might be zero), or FALSE if an error occurred.

Příklad 1. Getting all phone numbers out of some text.

preg_match_all ("/$? (\d{3})? $? (?(1) [\-\s] ) \d{3}-\d{4}/x", "Call 555-1212 or 1-800-555-1212", $phones);

Příklad 2. Find matching HTML tags (greedy)

// The \\2 is an example of backreferencing. This tells pcre that // it must match the second set of parentheses in the regular expression // itself, which would be the ([\w]+) in this case. The extra backslash is // required because the string is in double quotes. $html = "<b>bold text</b><a href=howdy.html>click me</a>"; preg_match_all ("/(<([\w]+)[^>]*>)(.*)(<\/\\2>)/", $html, $matches); for ($i=0; $i< count($matches[0]); $i++) { echo "matched: ".$matches[0][$i]."\n"; echo "part 1: ".$matches[1][$i]."\n"; echo "part 2: ".$matches[3][$i]."\n"; echo "part 3: ".$matches[4][$i]."\n\n"; }
This example will produce:

matched: <b>bold text</b> part 1: <b> part 2: bold text part 3: </b> matched: <a href=howdy.html>click me</a> part 1: <a href=howdy.html> part 2: click me part 3: </a>

preg_match

(PHP 3>= 3.0.9, PHP 4 )

preg_match -- Perform a regular expression match

Description

int preg_match ( string pattern, string subject [, array matches [, int flags]])

Searches subject for a match to the regular expression given in pattern.

If matches is provided, then it is filled with the results of search. $matches[0] will contain the text that matched the full pattern, $matches[1] will have the text that matched the first captured parenthesized subpattern, and so on.

flags can be the following flag:

PREG_OFFSET_CAPTURE: If this flag is set, for every occuring match the appendant string offset will also be returned. Note that this changes the return value in an array where every element is an array consisting of the matched string at offset 0 and it's string offset into subject at offset 1. This flag is available since PHP 4.3.0 .

The flags parameter is available since PHP 4.3.0 .

If pattern and replacement are arrays, then preg_replace() takes a value from each array and uses them to do search and replace on subject. If replacement has fewer values than pattern, then empty string is used for the rest of replacement values. If pattern is an array and replacement is a string, then this replacement string is used for every value of pattern. The converse would not make sense, though.

/e modifier makes preg_replace() treat the replacement parameter as PHP code after the appropriate references substitution is done. Tip: make sure that replacement constitutes a valid PHP code string, otherwise PHP will complain about a parse error at the line containing preg_replace().

Příklad 1. Replacing several values

$patterns = array ("/(19|20)(\d{2})-(\d{1,2})-(\d{1,2})/", "/^\s*{(\w+)}\s*=/"); $replace = array ("\\3/\\4/\\1\\2", "$\\1 ="); print preg_replace ($patterns, $replace, "{startDate} = 1999-5-27");
This example will produce:

$startDate = 5/27/1999

Příklad 2. Using /e modifier

preg_replace ("/(<\/?)(\w+)([^>]*>)/e", "'\\1'.strtoupper('\\2').'\\3'", $html_body);

This would capitalize all HTML tags in the input text.

Příklad 3. Convert HTML to text

// $document should contain an HTML document. // This will remove HTML tags, javascript sections // and white space. It will also convert some // common HTML entities to their text equivalent. $search = array ("'<script[^>]*?>.*?</script>'si", // Strip out javascript "'<[\/\!]*?[^<>]*?>'si", // Strip out html tags "'([\r\n])[\s]+'", // Strip out white space "'&(quot|#34);'i", // Replace html entities "'&(amp|#38);'i", "'&(lt|#60);'i", "'&(gt|#62);'i", "'&(nbsp|#160);'i", "'&(iexcl|#161);'i", "'&(cent|#162);'i", "'&(pound|#163);'i", "'&(copy|#169);'i", "'&#(\d+);'e"); // evaluate as php $replace = array ("", "", "\\1", "\"", "&", "<", ">", " ", chr(161), chr(162), chr(163), chr(169), "chr(\\1)"); $text = preg_replace ($search, $replace, $document);

Poznámka: Parameter limit was added after PHP 4.0.1pl2.

preg_split

(PHP 3>= 3.0.9, PHP 4 )

preg_split -- Split string by a regular expression

Description

array preg_split ( string pattern, string subject [, int limit [, int flags]])

Poznámka: Parameter flags was added in PHP 4 Beta 3.

Returns an array containing substrings of subject split along boundaries matched by pattern.

If limit is specified, then only substrings up to limit are returned, and if limit is -1, it actually means "no limit", which is useful for specifying the flags.

flags can be any combination of the following flags (combined with bitwise | operator):

PREG_SPLIT_NO_EMPTY: If this flag is set, only non-empty pieces will be returned by preg_split().
PREG_SPLIT_DELIM_CAPTURE: If this flag is set, parenthesized expression in the delimiter pattern will be captured and returned as well. This flag was added for 4.0.5.
PREG_SPLIT_OFFSET_CAPTURE: If this flag is set, for every occuring match the appendant string offset will also be returned. Note that this changes the return value in an array where every element is an array consisting of the matched string at offset 0 and it's string offset into subject at offset 1. This flag is available since PHP 4.3.0 .

Příklad 1. preg_split() example : Get the parts of a search string.

// split the phrase by any number of commas or space characters, // which include " ", \r, \t, \n and \f $keywords = preg_split ("/[\s,]+/", "hypertext language, programming");

Příklad 2. Splitting a string into component characters.

$str = 'string'; $chars = preg_split('//', $str, -1, PREG_SPLIT_NO_EMPTY); print_r($chars);

Příklad 3. Splitting a string into matches and their offsets.

$str = 'hypertext language programming'; $chars = preg_split('/ /', $str, -1, PREG_SPLIT_OFFSET_CAPTURE); print_r($chars);

will yield

Array ( [0] => Array ( [0] => hypertext [1] => 0 ) [1] => Array ( [0] => language [1] => 10 ) [2] => Array ( [0] => programming [1] => 19 ) )

LXXXVIII. qtdom functions

Obsah
qdom_error -- Returns the error string from the last QDOM operation or FALSE if no errors occured
qdom_tree -- creates a tree of an xml string

qdom_error

(PHP 4 >= 4.0.5)

qdom_error -- Returns the error string from the last QDOM operation or FALSE if no errors occured

Description

string qdom_error ( void)

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

qdom_tree

(PHP 4 >= 4.0.4)

qdom_tree -- creates a tree of an xml string

Description

object qdom_tree ( string )

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

LXXXIX. Regular Expression Functions (POSIX Extended)

Poznámka: PHP also supports regular expressions using a Perl-compatible syntax using the PCRE functions. Those functions support non-greedy matching, assertions, conditional subpatterns, and a number of other features not supported by the POSIX-extended regular expression syntax.

Varování

These regular expression functions are not binary-safe. The PCRE functions are.

Regular expressions are used for complex string manipulation in PHP. The functions that support regular expressions are:

These functions all take a regular expression string as their first argument. PHP uses the POSIX extended regular expressions as defined by POSIX 1003.2. For a full description of POSIX regular expressions see the regex man pages included in the regex directory in the PHP distribution. It's in manpage format, so you'll want to do something along the lines of man /usr/local/src/regex/regex.7 in order to read it.

Příklad 1. Regular Expression Examples

ereg ("abc", $string); /* Returns true if"abc" is found anywhere in $string. */ ereg ("^abc", $string); /* Returns true if "abc"; is found at the beginning of $string. */ ereg ("abc$", $string); /* Returns true if "abc" is found at the end of $string. */ eregi ("(ozilla.[23]|MSIE.3)", $HTTP_USER_AGENT); /* Returns true if client browser is Netscape 2, 3 or MSIE 3. */ ereg ("([[:alnum:]]+) ([[:alnum:]]+) ([[:alnum:]]+)", $string,$regs); /* Places three space separated words into $regs[1], $regs[2] and $regs[3]. */ $string = ereg_replace ("^", "<br />", $string); /* Put a <br /> tag at the beginning of $string. */ $string = ereg_replace ("$", "<br />", $string); /* Put a <br />; tag at the end of $string. */ $string = ereg_replace ("\n", "", $string); /* Get rid of any newline characters in $string. */

Obsah
ereg_replace -- Replace regular expression
ereg -- Regular expression match
eregi_replace -- replace regular expression case insensitive
eregi -- case insensitive regular expression match
split -- split string into array by regular expression
spliti -- Split string into array by regular expression case insensitive
sql_regcase -- Make regular expression for case insensitive match

ereg_replace

(PHP 3, PHP 4 )

ereg_replace -- Replace regular expression

Description

string ereg_replace ( string pattern, string replacement, string string)

Poznámka: preg_replace(), which uses a Perl-compatible regular expression syntax, is often a faster alternative to ereg_replace().

This function scans string for matches to pattern, then replaces the matched text with replacement.

The modified string is returned. (Which may mean that the original string is returned if there are no matches to be replaced.)

If pattern contains parenthesized substrings, replacement may contain substrings of the form \\digit, which will be replaced by the text matching the digit'th parenthesized substring; \\0 will produce the entire contents of string. Up to nine substrings may be used. Parentheses may be nested, in which case they are counted by the opening parenthesis.

If no matches are found in string, then string will be returned unchanged.

For example, the following code snippet prints "This was a test" three times:

Příklad 1. ereg_replace() Example

$string = "This is a test"; echo ereg_replace (" is", " was", $string); echo ereg_replace ("( )is", "\\1was", $string); echo ereg_replace ("(( )is)", "\\2was", $string);

One thing to take note of is that if you use an integer value as the replacement parameter, you may not get the results you expect. This is because ereg_replace() will interpret the number as the ordinal value of a character, and apply that. For instance:

Příklad 2. ereg_replace() Example

<?php /* This will not work as expected. */ $num = 4; $string = "This string has four words."; $string = ereg_replace('four', $num, $string); echo $string; /* Output: 'This string has words.' */ /* This will work. */ $num = '4'; $string = "This string has four words."; $string = ereg_replace('four', $num, $string); echo $string; /* Output: 'This string has 4 words.' */ ?>

Příklad 3. Replace URLs with links

$text = ereg_replace("[[:alpha:]]+://[^<>[:space:]]+[[:alnum:]/]", "<a href=\"\\0\">\\0</a>", $text);

ereg

(PHP 3, PHP 4 )

ereg -- Regular expression match

Description

int ereg ( string pattern, string string [, array regs])

Poznámka: preg_match(), which uses a Perl-compatible regular expression syntax, is often a faster alternative to ereg().

Searches a string for matches to the regular expression given in pattern.

If matches are found for parenthesized substrings of pattern and the function is called with the third argument regs, the matches will be stored in the elements of the array regs. $regs[1] will contain the substring which starts at the first left parenthesis; $regs[2] will contain the substring starting at the second, and so on. $regs[0] will contain a copy of the complete string matched.

Poznámka: Up to (and including) PHP 4.1.0 $regs will be filled with exactly ten elements, even though more or fewer than ten parenthesized substrings may actually have matched. This has no effect on ereg()'s ability to match more substrings. If no matches are found, $regs will not be altered by ereg().

Searching is case sensitive.

Returns TRUE if a match for pattern was found in string, or FALSE if no matches were found or an error occurred.

The following code snippet takes a date in ISO format (YYYY-MM-DD) and prints it in DD.MM.YYYY format:

Příklad 1. ereg() Example

if (ereg ("([0-9]{4})-([0-9]{1,2})-([0-9]{1,2})", $date, $regs)) { echo "$regs[3].$regs[2].$regs[1]"; } else { echo "Invalid date format: $date"; }

eregi_replace

(PHP 3, PHP 4 )

eregi_replace -- replace regular expression case insensitive

Description

string eregi_replace ( string pattern, string replacement, string string)

This function is identical to ereg_replace() except that this ignores case distinction when matching alphabetic characters.

See also ereg(), eregi(), and ereg_replace().

eregi

(PHP 3, PHP 4 )

eregi -- case insensitive regular expression match

Description

int eregi ( string pattern, string string [, array regs])

This function is identical to ereg() except that this ignores case distinction when matching alphabetic characters.

Příklad 1. eregi() example

if (eregi("z", $string)) { echo "'$string' contains a 'z' or 'Z'!"; }

split

(PHP 3, PHP 4 )

split -- split string into array by regular expression

Description

array split ( string pattern, string string [, int limit])

Poznámka: preg_split(), which uses a Perl-compatible regular expression syntax, is often a faster alternative to split().

Returns an array of strings, each of which is a substring of string formed by splitting it on boundaries formed by the regular expression pattern. If limit is set, the returned array will contain a maximum of limit elements with the last element containing the whole rest of string. If an error occurs, split() returns FALSE.

To split off the first four fields from a line from /etc/passwd:

Příklad 1. split() Example

list($user,$pass,$uid,$gid,$extra)= split (":", $passwd_line, 5);

Poznámka: If there are n occurrences of pattern, the returned array will contain n+1 items. For example, if there is no occurrence of pattern, an array with only one element will be returned. Of course, this is also true if string is empty.

To parse a date which may be delimited with slashes, dots, or hyphens:

Příklad 2. split() Example

$date = "04/30/1973"; // Delimiters may be slash, dot, or hyphen list ($month, $day, $year) = split ('[/.-]', $date); echo "Month: $month; Day: $day; Year: $year<br>\n";

Note that pattern is case-sensitive.

Note that if you don't require the power of regular expressions, it is faster to use explode(), which doesn't incur the overhead of the regular expression engine.

For users looking for a way to emulate Perl's @chars = split('', $str) behaviour, please see the examples for preg_split().

Please note that pattern is a regular expression. If you want to split on any of the characters which are considered special by regular expressions, you'll need to escape them first. If you think split() (or any other regex function, for that matter) is doing something weird, please read the file regex.7, included in the regex/ subdirectory of the PHP distribution. It's in manpage format, so you'll want to do something along the lines of man /usr/local/src/regex/regex.7 in order to read it.

spliti

(PHP 4 >= 4.0.1)

spliti -- Split string into array by regular expression case insensitive

Description

array spliti ( string pattern, string string [, int limit])

This function is identical to split() except that this ignores case distinction when matching alphabetic characters.

See also preg_spliti(), split(), explode(), and implode().

sql_regcase

(PHP 3, PHP 4 )

sql_regcase -- Make regular expression for case insensitive match

Description

string sql_regcase ( string string)

Returns a valid regular expression which will match string, ignoring case. This expression is string with each character converted to a bracket expression; this bracket expression contains that character's uppercase and lowercase form if applicable, otherwise it contains the original character twice.

Příklad 1. sql_regcase() Example

echo sql_regcase ("Foo bar");
prints

[Ff][Oo][Oo] [Bb][Aa][Rr]
.

This can be used to achieve case insensitive pattern matching in products which support only case sensitive regular expressions.

XC. Funkce pro práci se semafory a sdílenou pamětí

Tato extenze poskytuje semaforové funkce využívající System V semafory. Semafory se dají používat k poskytování exkluzivního přístupu k prostředkům na daném systému, nebo k omezení počtu procesů, které mohou současně používat určitý prostředek.

Tato extenze také poskytuje funkce pro práci se sdílenou pamětí využívající System V sdílenou paměť. Sdílená pmět se dá používat k poskytování přístupu ke globálním proměnným. Různí httpd-daemoni a dokonce i jiné programy (např. Perl, C, ...) mohou k těmto datům přistupovat, a vytvořit tak globální výměnu dat. Pamatujte, že sdílená paměť není chráněna proti simultáním přístupům. K synchronizaci použijte semafory.

Tabulka 1. Omezení sdílené paměti systémem Unix

SHMMAX	max. velikost sdílené paměti, normálně 131072 bytů
SHMMIN	min. velikost sdílené paměti, normálne 1 byte
SHMMNI	max. počet segmentů sdílené paměti, normálně 100
SHMSEG	max. počet segmentů sdílené paměti na proces, normálně 6

Poznámka: Tyto funkce nefungují na Windows.

Obsah
ftok -- Convert a pathname and a project identifier to a System V IPC key
msg_get_queue -- Create or attach to a message queue
msg_receive -- Receive a message from a message queue
msg_remove_queue -- Destroy a message queue
msg_send -- Send a message to a message queue
msg_set_queue -- Set information in the message queue data structure
msg_stat_queue -- Returns information from the message queue data structure
sem_acquire -- Získat semafor
sem_get -- Získat id semaforu
sem_release -- Uvolnit semafor
sem_remove -- Remove a semaphore
shm_attach -- Vytvořit nebo otevřít segment sdílené paměti
shm_detach -- Odpojit se od segmentu sdílené paměti
shm_get_var -- Vrátit proměnnou ze sdílené paměti
shm_put_var -- Vložit nebo modifikovat proměnnou do sdílené paměti
shm_remove_var -- Odstranit proměnnou ze sdílené paměti
shm_remove -- Odstranit sdílenou paměť ze systému

unserialize defaults to TRUE; if it is set to TRUE, the message is treated as though it was serialized using the same mechanism as the session module. The message will be unserialized and then returned to your script. This allows you to easily receive arrays or complex object structures from other PHP scripts, or if you are using the WDDX serializer, from any WDDX compatible source. If unserialize is FALSE, the message will be returned as a binary-safe string.

The optional flags allows you to pass flags to the low-level msgrcv system call. It defaults to 0, but you may specify one or more of the following values (by adding or ORing them together).

Tabulka 1. Flag values for msg_receive

MSG_IPC_NOWAIT	If there are no messages of the `desiredmsgtype`, return immediately and do not wait. The function will fail and return an integer value corresponding to ENOMSG.
MSG_EXCEPT	Using this flag in combination with a `desiredmsgtype` greater than 0 will cause the function to receive the first message that is not equal to `desiredmsgtype`.
MSG_NOERROR	If the message is longer than `maxsize`, setting this flag will truncate the message to `maxsize` and will not signal an error.

Upon successful completion the message queue data structure is updated as follows: msg_lrpid is set to the process-ID of the calling process, msg_qnum is decremented by 1 and msg_rtime is set to the current time.

msg_receive() returns TRUE on success or FALSE on failure. If the function fails, the optional errorcode will be set to the value of the system errno variable.

This function was introduced in PHP 4.3.0 (not yet released).

msg_remove_queue

(PHP 4 CVS only)

msg_remove_queue -- Destroy a message queue

Description

bool msg_remove_queue ( int queue)

msg_remove_queue() destroys the message queue specified by the queue. Only use this function when all processes have finished working with the message queue and you need to release the system resources held by it.

See also: msg_remove_queue(), msg_receive(), msg_stat_queue() and msg_set_queue().

This function was introduced in PHP 4.3.0 (not yet released).

msg_send

(PHP 4 CVS only)

msg_send -- Send a message to a message queue

Description

bool msg_send ( int queue, int msgtype, mixed message [, bool serialize [, bool blocking [, int errorcode]]])

msg_send() sends a message of type msgtype (which MUST be greater than 0) to a the message queue specified by queue.

If the message is too large to fit in the queue, your script will wait until another process reads messages from the queue and frees enough space for your message to be sent. This is called blocking; you can prevent blocking by setting the optional blocking parameter to FALSE, in which case msg_send() will immediately return FALSE if the message is too big for the queue, and set the optional errorcode to EAGAIN, indicating that you should try to send your message again a little later on.

The optional serialize controls how the message is sent. serialize defaults to TRUE which means that the message is serialized using the same mechanism as the session module before being sent to the queue. This allows complex arrays and objects to be sent to other PHP scripts, or if you are using the WDDX serializer, to any WDDX compatible client.

Upon successful completion the message queue data structure is updated as follows: msg_lspid is set to the process-ID of the calling process, msg_qnum is incremented by 1 and msg_stime is set to the current time.

This function was introduced in PHP 4.3.0 (not yet released).

msg_set_queue

(PHP 4 CVS only)

msg_set_queue -- Set information in the message queue data structure

Description

bool msg_set_queue ( int queue, array data)

msg_set_queue() allows you to change the values of the msg_perm.uid, msg_perm.gid, msg_perm.mode and msg_qbytes fields of the underlying message queue data structure. You specify the values you require by setting the value of the keys that you require in the data array.

Changing the data structure will require that PHP be running as the same user that created the the queue, owns the queue (as determined by the existing msg_perm.xxx fields), or be running with root privileges. root privileges are required to raise the msg_qbytes values above the system defined limit.

See also: msg_remove_queue(), msg_receive(), msg_stat_queue() and msg_set_queue().

This function was introduced in PHP 4.3.0 (not yet released).

msg_stat_queue

(PHP 4 CVS only)

msg_stat_queue -- Returns information from the message queue data structure

Description

array msg_stat_queue ( int queue)

msg_stat_queue() returns the message queue meta data for the message queue specified by the queue. This is useful, for example, to determine which process sent the message that was just received.

The return value is an array whose keys and values have the following meanings:

Tabulka 1. Array structure for msg_stat_queue

msg_perm.uid	The uid of the owner of the queue.
msg_perm.gid	The gid of the owner of the queue.
msg_perm.mode	The file access mode of the queue.
msg_stime	The time that the last message was sent to the queue.
msg_rtime	The time that the last message was received from the queue.
msg_ctime	The time that the queue was last changed.
msg_qnum	The number of messages waiting to be read from the queue.
msg_qbytes	The number of bytes of space currently available in the queue to hold sent messages until they are received.
msg_lspid	The pid of the process that sent the last message to the queue.
msg_lrpid	The pid of the process that received the last message from the queue.

See also: msg_remove_queue(), msg_receive(), msg_stat_queue() and msg_set_queue().

This function was introduced in PHP 4.3.0 (not yet released).

sem_acquire

(PHP 3>= 3.0.6, PHP 4 )

sem_acquire -- Získat semafor

Popis

int sem_acquire ( int sem_identifier)

Při úspěchu vrací TRUE, při chybě FALSE.

sem_acquire() blokuje (pokud je optřeba) až do získání semaforu. Proces pokoušející se získat semafor, který už získal bude blokovat navěky, pokud by získání tohoto semaforu způsobilo překročení jeho hodnoty max_acquire.

Po zpracování požadavku se všechny získané, ale explicitně neuvolněné semafoty uvolní automaticky, a vygeneruje se varování.

Viz také: sem_get() a sem_release().

sem_get

(PHP 3>= 3.0.6, PHP 4 )

sem_get -- Získat id semaforu

Popis

int sem_get ( int key [, int max_acquire [, int perm]])

Vrací idenfifikátor semaforu nebo FALSE.

sem_get() vrací id, které se dá použít k přístupu k System V semaforu s daným klíčem. Podle potřeby se vytvoří nový semafor s přístupovými právy definovanými v perm (default je 0666). Počet procesů, které mohou tento semafor získat současně je max_acquire (default je 1). Tato hodnota je ale nastavena pouze pokud tento proces zjistí, že k tomuto semaforu není současně připojen jiný proces.

Druhé volání sem_get() se stejným key vrátí jiný identifikátor semaforu, ale oba identifikátory ukazují na stejný semafor.

Viz také: sem_acquire() a sem_release().

Poznámka: Tato funkce nefunguje na Windows.

sem_release

(PHP 3>= 3.0.6, PHP 4 )

sem_release -- Uvolnit semafor

Popis

int sem_release ( int sem_identifier)

Při úspěchu vrací TRUE, jinak FALSE.

sem_release() uvolňí semafor, pokud ho volající proces drží, jinak se vygeneruje varování.

Po uvolnění může být semafor znovu získán pomocí sem_acquire().

Viz také: sem_get() a sem_acquire().

Poznámka: Tato funkce nefunguje na Windows.

sem_remove

(PHP 4 >= 4.1.0)

sem_remove -- Remove a semaphore

Description

bool sem_remove ( int sem_identifier)

Returns: TRUE on success, FALSE on error.

sem_remove() removes the semaphore sem_identifier if it has been created by sem_get(), otherwise generates a warning.

After removing the semaphore, it is no more accessible.

Poznámka: This function does not work on Windows systems. It was added on PHP 4.1.0.

shm_attach

(PHP 3>= 3.0.6, PHP 4 )

shm_attach -- Vytvořit nebo otevřít segment sdílené paměti

Popis

int shm_attach ( int key [, int memsize [, int perm]])

shm_attach() vrací id, které se dá použít k přístupu k System V sdílené paměti s daným klíčem; první volání vytvoří segment paměti o velikosti mem_size (default: sysvshm.init_mem v konfiguračním souboru, jinak 10000 bytů) a s volitelnými právy (default: 0666).

Druhé volání shm_attach() se stejným key vrátí jiný identifikáto, ale oba ukazují na stejnou sdílenou paměť. memsize a perm se v takovém případě ignorují.

Poznámka: Tato funkce nefunguje na Windows.

shm_detach

(PHP 3>= 3.0.6, PHP 4 )

shm_detach -- Odpojit se od segmentu sdílené paměti

Popis

Odstraní sdílenou paměť z UNIXového systému. Všechna data v ní budou zničena.

Poznámka: Tato funkce nefunguje na Windows.

XCI. SESAM database functions

SESAM/SQL-Server is a mainframe database system, developed by Fujitsu Siemens Computers, Germany. It runs on high-end mainframe servers using the operating system BS2000/OSD.

In numerous productive BS2000 installations, SESAM/SQL-Server has proven ...

the ease of use of Java-, Web- and client/server connectivity,
the capability to work with an availability of more than 99.99%,
the ability to manage tens and even hundreds of thousands of users.

Now there is a PHP3 SESAM interface available which allows database operations via PHP-scripts.

Configuration notes: There is no standalone support for the PHP SESAM interface, it works only as an integrated Apache module. In the Apache PHP module, this SESAM interface is configured using Apache directives.
Tabulka 1. SESAM Configuration directives
Directive Meaning
php3_sesam_oml
Name of BS2000 PLAM library containing the loadable SESAM driver modules. Required for using SESAM functions.
Example:
php3_sesam_oml $.SYSLNK.SESAM-SQL.030
php3_sesam_configfile
Name of SESAM application configuration file. Required for using SESAM functions.
Example:
php3_sesam_configfile $SESAM.SESAM.CONF.AW
It will usually contain a configuration like (see SESAM reference manual):
CNF=B
NAM=K
NOTYPE
php3_sesam_messagecatalog
Name of SESAM message catalog file. In most cases, this directive is not neccessary. Only if the SESAM message file is not installed in the system's BS2000 message file table, it can be set with this directive.
Example:
php3_sesam_messagecatalog $.SYSMES.SESAM-SQL.030
In addition to the configuration of the PHP/SESAM interface, you have to configure the SESAM-Database server itself on your mainframe as usual. That means:

starting the SESAM database handler (DBH), and

connecting the databases with the SESAM database handler

To get a connection between a PHP script and the database handler, the CNF and NAM parameters of the selected SESAM configuration file must match the id of the started database handler.

In case of distributed databases you have to start a SESAM/SQL-DCN agent with the distribution table including the host and database names.

The communication between PHP (running in the POSIX subsystem) and the database handler (running outside the POSIX subsystem) is realized by a special driver module called SQLSCI and SESAM connection modules using common memory. Because of the common memory access, and because PHP is a static part of the web server, database accesses are very fast, as they do not require remote accesses via ODBC, JDBC or UTM.

Only a small stub loader (SESMOD) is linked with PHP, and the SESAM connection modules are pulled in from SESAM's OML PLAM library. In the configuration, you must tell PHP the name of this PLAM library, and the file link to use for the SESAM configuration file (As of SESAM V3.0, SQLSCI is available in the SESAM Tool Library, which is part of the standard distribution).

Because the SQL command quoting for single quotes uses duplicated single quotes (as opposed to a single quote preceded by a backslash, used in some other databases), it is advisable to set the PHP configuration directives php3_magic_quotes_gpc and php3_magic_quotes_sybase to On for all PHP scripts using the SESAM interface.

Runtime considerations: Because of limitations of the BS2000 process model, the driver can be loaded only after the Apache server has forked off its server child processes. This will slightly slow down the initial SESAM request of each child, but subsequent accesses will respond at full speed.

When explicitly defining a Message Catalog for SESAM, that catalog will be loaded each time the driver is loaded (i.e., at the initial SESAM request). The BS2000 operating system prints a message after successful load of the message catalog, which will be sent to Apache's error_log file. BS2000 currently does not allow suppression of this message, it will slowly fill up the log.

Make sure that the SESAM OML PLAM library and SESAM configuration file are readable by the user id running the web server. Otherwise, the server will be unable to load the driver, and will not allow to call any SESAM functions. Also, access to the database must be granted to the user id under which the Apache server is running. Otherwise, connections to the SESAM database handler will fail.

Cursor Types: The result cursors which are allocated for SQL "select type" queries can be either "sequential" or "scrollable". Because of the larger memory overhead needed by "scrollable" cursors, the default is "sequential".

When using "scrollable" cursors, the cursor can be freely positioned on the result set. For each "scrollable" query, there are global default values for the scrolling type (initialized to: SESAM_SEEK_NEXT) and the scrolling offset which can either be set once by sesam_seek_row() or each time when fetching a row using sesam_fetch_row(). When fetching a row using a "scrollable" cursor, the following post-processing is done for the global default values for the scrolling type and scrolling offset:

Tabulka 2. Scrolled Cursor Post-Processing

Scroll Type Action

SESAM_SEEK_NEXT none

SESAM_SEEK_PRIOR none

SESAM_SEEK_FIRST set scroll type to SESAM_SEEK_NEXT

SESAM_SEEK_LAST set scroll type to SESAM_SEEK_PRIOR

SESAM_SEEK_ABSOLUTE Auto-Increment internal offset value

SESAM_SEEK_RELATIVE none. (maintain global default offset value, which allows for, e.g., fetching each 10th row backwards)

Porting note: Because in the PHP world it is natural to start indexes at zero (rather than 1), some adaptions have been made to the SESAM interface: whenever an indexed array is starting with index 1 in the native SESAM interface, the PHP interface uses index 0 as a starting point. E.g., when retrieving columns with sesam_fetch_row(), the first column has the index 0, and the subsequent columns have indexes up to (but not including) the column count ($array["count"]). When porting SESAM applications from other high level languages to PHP, be aware of this changed interface. Where appropriate, the description of the respective php sesam functions include a note that the index is zero based.

Security concerns: When allowing access to the SESAM databases, the web server user should only have as little privileges as possible. For most databases, only read access privilege should be granted. Depending on your usage scenario, add more access rights as you see fit. Never allow full control to any database for any user from the 'net! Restrict access to php scripts which must administer the database by using password control and/or SSL security.

Migration from other SQL databases: No two SQL dialects are ever 100% compatible. When porting SQL applications from other database interfaces to SESAM, some adaption may be required. The following typical differences should be noted:

Vendor specific data types

Some vendor specific data types may have to be replaced by standard SQL data types (e.g., TEXT could be replaced by VARCHAR(max. size)).

Keywords as SQL identifiers

In SESAM (as in standard SQL), such identifiers must be enclosed in double quotes (or renamed).

Display length in data types

SESAM data types have a precision, not a display length. Instead of int(4) (intended use: integers up to '9999'), SESAM requires simply int for an implied size of 31 bits. Also, the only datetime data types available in SESAM are: DATE, TIME(3) and TIMESTAMP(3).

SQL types with vendor-specific unsigned, zerofill, or auto_increment attributes

Unsigned and zerofill are not supported. Auto_increment is automatic (use "INSERT ... VALUES(*, ...)" instead of "... VALUES(0, ...)" to take advantage of SESAM-implied auto-increment.

int ... DEFAULT '0000'

Numeric variables must not be initialized with string constants. Use DEFAULT 0 instead. To initialize variables of the datetime SQL data types, the initialization string must be prefixed with the respective type keyword, as in: CREATE TABLE exmpl ( xtime timestamp(3) DEFAULT TIMESTAMP '1970-01-01 00:00:00.000' NOT NULL );

$count = xxxx_num_rows();

Some databases promise to guess/estimate the number of the rows in a query result, even though the returned value is grossly incorrect. SESAM does not know the number of rows in a query result before actually fetching them. If you REALLY need the count, try SELECT COUNT(...) WHERE ..., it will tell you the number of hits. A second query will (hopefully) return the results.

DROP TABLE thename;

In SESAM, in the DROP TABLE command, the table name must be either followed by the keyword RESTRICT or CASCADE. When specifying RESTRICT, an error is returned if there are dependent objects (e.g., VIEWs), while with CASCADE, dependent objects will be deleted along with the specified table.

Notes on the use of various SQL types: SESAM does not currently support the BLOB type. A future version of SESAM will have support for BLOB.

At the PHP interface, the following type conversions are automatically applied when retrieving SQL fields:

Tabulka 3. SQL to PHP Type Conversions

SQL Type PHP Type

SMALLINT, INTEGER integer

NUMERIC, DECIMAL, FLOAT, REAL, DOUBLE float

DATE, TIME, TIMESTAMP string

VARCHAR, CHARACTER string
When retrieving a complete row, the result is returned as an array. Empty fields are not filled in, so you will have to check for the existence of the individual fields yourself (use isset() or empty() to test for empty fields). That allows more user control over the appearance of empty fields (than in the case of an empty string as the representation of an empty field).

Support of SESAM's "multiple fields" feature: The special "multiple fields" feature of SESAM allows a column to consist of an array of fields. Such a "multiple field" column can be created like this:
Příklad 1. Creating a "multiple field" column
CREATE TABLE multi_field_test (
    pkey CHAR(20) PRIMARY KEY,
    multi(3) CHAR(12)
)
and can be filled in using:
Příklad 2. Filling a "multiple field" column
INSERT INTO multi_field_test (pkey, multi(2..3) )
    VALUES ('Second', <'first_val', 'second_val'>)
Note that (like in this case) leading empty sub-fields are ignored, and the filled-in values are collapsed, so that in the above example the result will appear as multi(1..2) instead of multi(2..3).
When retrieving a result row, "multiple columns" are accessed like "inlined" additional columns. In the example above, "pkey" will have the index 0, and the three "multi(1..3)" columns will be accessible as indices 1 through 3.

For specific SESAM details, please refer to the SESAM/SQL-Server documentation (english) or the SESAM/SQL-Server documentation (german), both available online, or use the respective manuals.

Obsah
sesam_affected_rows -- Get number of rows affected by an immediate query
sesam_commit -- Commit pending updates to the SESAM database
sesam_connect -- Open SESAM database connection
sesam_diagnostic -- Return status information for last SESAM call
sesam_disconnect -- Detach from SESAM connection
sesam_errormsg -- Returns error message of last SESAM call
sesam_execimm -- Execute an "immediate" SQL-statement
sesam_fetch_array -- Fetch one row as an associative array
sesam_fetch_result -- Return all or part of a query result
sesam_fetch_row -- Fetch one row as an array
sesam_field_array -- Return meta information about individual columns in a result
sesam_field_name -- Return one column name of the result set
sesam_free_result -- Releases resources for the query
sesam_num_fields -- Return the number of fields/columns in a result set
sesam_query -- Perform a SESAM SQL query and prepare the result
sesam_rollback -- Discard any pending updates to the SESAM database
sesam_seek_row -- Set scrollable cursor mode for subsequent fetches
sesam_settransaction -- Set SESAM transaction parameters

sesam_affected_rows

(PHP 3 CVS only)

sesam_affected_rows -- Get number of rows affected by an immediate query

Description

int sesam_affected_rows ( string result_id)

result_id is a valid result id returned by sesam_query().

Returns the number of rows affected by a query associated with result_id.

The sesam_affected_rows() function can only return useful values when used in combination with "immediate" SQL statements (updating operations like INSERT, UPDATE and DELETE) because SESAM does not deliver any "affected rows" information for "select type" queries. The number returned is the number of affected rows.

$result = sesam_execimm ("DELETE FROM PHONE WHERE LASTNAME = '".strtoupper ($name)."'");
if (!$result) {
    ... error ...
}
print sesam_affected_rows ($result).
    " entries with last name ".$name." deleted.\n"

sesam_commit

(PHP 3 CVS only)

sesam_commit -- Commit pending updates to the SESAM database

Description

bool sesam_commit ( void)

Returns: TRUE on success, FALSE on errors

sesam_commit() commits any pending updates to the database.

Note that there is no "auto-commit" feature as in other databases, as it could lead to accidental data loss. Uncommitted data at the end of the current script (or when calling sesam_disconnect()) will be discarded by an implied sesam_rollback() call.

See also: sesam_rollback().

Příklad 1. Committing an update to the SESAM database

<?php if (sesam_connect ("mycatalog", "myschema", "otto")) { if (!sesam_execimm ("INSERT INTO mytable VALUES (*, 'Small Test', <0, 8, 15>)")) die("insert failed"); if (!sesam_commit()) die("commit failed"); } ?>

sesam_connect

(PHP 3 CVS only)

sesam_connect -- Open SESAM database connection

Description

bool sesam_connect ( string catalog, string schema, string user)

string sesam_errormsg ( void)

Returns the SESAM error message associated with the most recent SESAM error.

if (!sesam_execimm ($stmt))
  printf ("%s<br>\n", sesam_errormsg());

See also: sesam_diagnostic() for the full set of SESAM SQL status information

sesam_execimm

(PHP 3 CVS only)

sesam_execimm -- Execute an "immediate" SQL-statement

Description

string sesam_execimm ( string query)

Returns: A SESAM "result identifier" on success, or FALSE on error.

sesam_execimm() executes an "immediate" statement (i.e., a statement like UPDATE, INSERT or DELETE which returns no result, and has no INPUT or OUTPUT variables). "select type" queries can not be used with sesam_execimm(). Sets the affected_rows value for retrieval by the sesam_affected_rows() function.

Note that sesam_query() can handle both "immediate" and "select-type" queries. Use sesam_execimm() only if you know beforehand what type of statement will be executed. An attempt to use SELECT type queries with sesam_execimm() will return $err["sqlstate"] == "42SBW".

The returned "result identifier" can not be used for retrieving anything but the sesam_affected_rows(); it is only returned for symmetry with the sesam_query() function.

$stmt = "INSERT INTO mytable VALUES ('one', 'two')";
$result = sesam_execimm ($stmt);
$err = sesam_diagnostic();
print ("sqlstate = ".$err["sqlstate"]."\n".
       "Affected rows = ".$err["rowcount"]." == ".
       sesam_affected_rows($result)."\n");

See also: sesam_query() and sesam_affected_rows().

sesam_fetch_array

(PHP 3 CVS only)

sesam_fetch_array -- Fetch one row as an associative array

Description

array sesam_fetch_array ( string result_id [, int whence [, int offset]])

Returns an array that corresponds to the fetched row, or FALSE if there are no more rows.

sesam_fetch_array() is an alternative version of sesam_fetch_row(). Instead of storing the data in the numeric indices of the result array, it stores the data in associative indices, using the field names as keys.

result_id is a valid result id returned by sesam_query() (select type queries only!).

For the valid values of the optional whenceand offset parameters, see the sesam_fetch_row() function for details.

sesam_fetch_array() fetches one row of data from the result associated with the specified result identifier. The row is returned as an associative array. Each result column is stored with an associative index equal to its column (aka. field) name. The column names are converted to lower case.

Columns without a field name (e.g., results of arithmetic operations) and empty fields are not stored in the array. Also, if two or more columns of the result have the same column names, the later column will take precedence. In this situation, either call sesam_fetch_row() or make an alias for the column.

SELECT TBL1.COL AS FOO, TBL2.COL AS BAR FROM TBL1, TBL2

A special handling allows fetching "multiple field" columns (which would otherwise all have the same column names). For each column of a "multiple field", the index name is constructed by appending the string "(n)" where n is the sub-index of the multiple field column, ranging from 1 to its declared repetition factor. The indices are NOT zero based, in order to match the nomenclature used in the respective query syntax. For a column declared as:

CREATE TABLE ... ( ... MULTI(3) INT )

the associative indices used for the individual "multiple field" columns would be "multi(1)", "multi(2)", and "multi(3)" respectively.

Subsequent calls to sesam_fetch_array() would return the next (or prior, or n'th next/prior, depending on the scroll attributes) row in the result set, or FALSE if there are no more rows.

Příklad 1. SESAM fetch array

<?php
$result = sesam_query ("SELECT * FROM phone\n".
                       "  WHERE LASTNAME='".strtoupper($name)."'\n".
                       "  ORDER BY FIRSTNAME", 1);
if (!$result) {
    ... error ...
}
// print the table:
print "<TABLE BORDER>\n";
while (($row = sesam_fetch_array ($result)) && count ($row) > 0) {
    print " <TR>\n";
    print " <TD>".htmlspecialchars ($row["firstname"])."</TD>\n";
    print " <TD>".htmlspecialchars ($row["lastname"])."</TD>\n";
    print " <TD>".htmlspecialchars ($row["phoneno"])."</TD>\n";
    print " </TR>\n";
}
print "</TABLE>\n";
sesam_free_result ($result);
?>

See also: sesam_fetch_row() which returns an indexed array.

sesam_fetch_result

(PHP 3 CVS only)

sesam_fetch_result -- Return all or part of a query result

Description

mixed sesam_fetch_result ( string result_id [, int max_rows])

Returns a mixed array with the query result entries, optionally limited to a maximum of max_rows rows. Note that both row and column indexes are zero-based.

Tabulka 1. Mixed result set returned by sesam_fetch_result()

Array Element	Contents
int $arr["count"]	number of columns in result set (or zero if this was an "immediate" query)
int $arr["rows"]	number of rows in result set (between zero and `max_rows`)
bool $arr["truncated"]	`TRUE` if the number of rows was at least `max_rows`, `FALSE` otherwise. Note that even when this is `TRUE`, the next sesam_fetch_result() call may return zero rows because there are no more result entries.
mixed $arr[col][row]	result data for all the fields at row(`row`) and column(`col`), (where the integer index `row` is between 0 and `$arr["rows"]-1`, and `col` is between 0 and `$arr["count"]-1`). Fields may be empty, so you must check for the existence of a field by using the php isset() function. The type of the returned fields depend on the respective SQL type declared for its column (see SESAM overview for the conversions applied). SESAM "multiple fields" are "inlined" and treated like a sequence of columns.

Note that the amount of memory used up by a large query may be gigantic. Use the max_rows parameter to limit the maximum number of rows returned, unless you are absolutely sure that your result will not use up all available memory.

See also: sesam_fetch_row(), and sesam_field_array() to check for "multiple fields". See the description of the sesam_query() function for a complete example using sesam_fetch_result().

sesam_fetch_row

(PHP 3 CVS only)

sesam_fetch_row -- Fetch one row as an array

Description

array sesam_fetch_row ( string result_id [, int whence [, int offset]])

Returns an array that corresponds to the fetched row, or FALSE if there are no more rows.

The number of columns in the result set is returned in an associative array element $array["count"]. Because some of the result columns may be empty, the count() function can not be used on the result row returned by sesam_fetch_row().

result_id is a valid result id returned by sesam_query() (select type queries only!).

whence is an optional parameter for a fetch operation on "scrollable" cursors, which can be set to the following predefined constants:

Tabulka 1. Valid values for "whence" parameter

Value	Constant	Meaning
0	`SESAM_SEEK_NEXT`	read sequentially (after fetch, the internal default is set to `SESAM_SEEK_NEXT`)
1	`SESAM_SEEK_PRIOR`	read sequentially backwards (after fetch, the internal default is set to `SESAM_SEEK_PRIOR`)
2	`SESAM_SEEK_FIRST`	rewind to first row (after fetch, the default is set to `SESAM_SEEK_NEXT`)
3	`SESAM_SEEK_LAST`	seek to last row (after fetch, the default is set to `SESAM_SEEK_PRIOR`)
4	`SESAM_SEEK_ABSOLUTE`	seek to absolute row number given as `offset` (Zero-based. After fetch, the internal default is set to `SESAM_SEEK_ABSOLUTE`, and the internal offset value is auto-incremented)
5	`SESAM_SEEK_RELATIVE`	seek relative to current scroll position, where `offset` can be a positive or negative offset value.

This parameter is only valid for "scrollable" cursors.

When using "scrollable" cursors, the cursor can be freely positioned on the result set. If the whence parameter is omitted, the global default values for the scrolling type (initialized to: SESAM_SEEK_NEXT, and settable by sesam_seek_row()) are used. If whence is supplied, its value replaces the global default.

offset is an optional parameter which is only evaluated (and required) if whence is either SESAM_SEEK_RELATIVE or SESAM_SEEK_ABSOLUTE. This parameter is only valid for "scrollable" cursors.

sesam_fetch_row() fetches one row of data from the result associated with the specified result identifier. The row is returned as an array (indexed by values between 0 and $array["count"]-1). Fields may be empty, so you must check for the existence of a field by using the php isset() function. The type of the returned fields depend on the respective SQL type declared for its column (see SESAM overview for the conversions applied). SESAM "multiple fields" are "inlined" and treated like a sequence of columns.

Subsequent calls to sesam_fetch_row() would return the next (or prior, or n'th next/prior, depending on the scroll attributes) row in the result set, or FALSE if there are no more rows.

Příklad 1. SESAM fetch rows

<?php
$result = sesam_query ("SELECT * FROM phone\n".
                       "  WHERE LASTNAME='".strtoupper($name)."'\n".
                       "  ORDER BY FIRSTNAME", 1);
if (!$result) {
    ... error ...
}
// print the table in backward order
print "<TABLE BORDER>\n";
$row = sesam_fetch_row ($result, SESAM_SEEK_LAST);
while (is_array ($row)) {
    print " <TR>\n";
    for ($col = 0; $col < $row["count"]; ++$col) {
        print "  <TD>".htmlspecialchars ($row[$col])."</TD>\n";
    }
    print " </TR>\n";
    // use implied SESAM_SEEK_PRIOR
    $row = sesam_fetch_row ($result);
}
print "</TABLE>\n";
sesam_free_result ($result);
?>

See also: sesam_fetch_array() which returns an associative array, and sesam_fetch_result() which returns many rows per invocation.

sesam_field_array

(PHP 3 CVS only)

sesam_field_array -- Return meta information about individual columns in a result

Description

array sesam_field_array ( string result_id)

result_id is a valid result id returned by sesam_query().

Returns a mixed associative/indexed array with meta information (column name, type, precision, ...) about individual columns of the result after the query associated with result_id.

Tabulka 1. Mixed result set returned by sesam_field_array()

Array Element	Contents
int $arr["count"]	Total number of columns in result set (or zero if this was an "immediate" query). SESAM "multiple fields" are "inlined" and treated like the respective number of columns.
string $arr[col]["name"]	column name for column(`col`), where `col` is between 0 and `$arr["count"]-1`. The returned value can be the empty string (for dynamically computed columns). SESAM "multiple fields" are "inlined" and treated like the respective number of columns, each with the same column name.
string $arr[col]["count"]	The "count" attribute describes the repetition factor when the column has been declared as a "multiple field". Usually, the "count" attribute is 1. The first column of a "multiple field" column however contains the number of repetitions (the second and following column of the "multiple field" contain a "count" attribute of 1). This can be used to detect "multiple fields" in the result set. See the example shown in the sesam_query() description for a sample use of the "count" attribute.
string $arr[col]["type"]	php variable type of the data for column(`col`), where `col` is between 0 and `$arr["count"]-1`. The returned value can be one of integer float string depending on the SQL type of the result. SESAM "multiple fields" are "inlined" and treated like the respective number of columns, each with the same php type.
string $arr[col]["sqltype"]	SQL variable type of the column data for column(`col`), where `col` is between 0 and `$arr["count"]-1`. The returned value can be one of "CHARACTER" "VARCHAR" "NUMERIC" "DECIMAL" "INTEGER" "SMALLINT" "FLOAT" "REAL" "DOUBLE" "DATE" "TIME" "TIMESTAMP" describing the SQL type of the result. SESAM "multiple fields" are "inlined" and treated like the respective number of columns, each with the same SQL type.
string $arr[col]["length"]	The SQL "length" attribute of the SQL variable in column(`col`), where `col` is between 0 and `$arr["count"]-1`. The "length" attribute is used with "CHARACTER" and "VARCHAR" SQL types to specify the (maximum) length of the string variable. SESAM "multiple fields" are "inlined" and treated like the respective number of columns, each with the same length attribute.
string $arr[col]["precision"]	The "precision" attribute of the SQL variable in column(`col`), where `col` is between 0 and `$arr["count"]-1`. The "precision" attribute is used with numeric and time data types. SESAM "multiple fields" are "inlined" and treated like the respective number of columns, each with the same precision attribute.
string $arr[col]["scale"]	The "scale" attribute of the SQL variable in column(`col`), where `col` is between 0 and `$arr["count"]-1`. The "scale" attribute is used with numeric data types. SESAM "multiple fields" are "inlined" and treated like the respective number of columns, each with the same scale attribute.

See the sesam_query() function for an example of the sesam_field_array() use.

sesam_field_name

(PHP 3 CVS only)

sesam_field_name -- Return one column name of the result set

Description

int sesam_field_name ( string result_id, int index)

Returns the name of a field (i.e., the column name) in the result set, or FALSE on error.

For "immediate" queries, or for dynamic columns, an empty string is returned.

Poznámka: The column index is zero-based, not one-based as in SESAM.

See also: sesam_field_array(). It provides an easier interface to access the column names and types, and allows for detection of "multiple fields".

sesam_free_result

(PHP 3 CVS only)

sesam_free_result -- Releases resources for the query

Description

Description

bool sesam_rollback ( void)

Returns: TRUE on success, FALSE on errors

sesam_rollback() discards any pending updates to the database. Also affected are result cursors and result descriptors.

At the end of each script, and as part of the sesam_disconnect() function, an implied sesam_rollback() is executed, discarding any pending changes to the database.

See also: sesam_commit().

Příklad 1. Discarding an update to the SESAM database

<?php if (sesam_connect ("mycatalog", "myschema", "otto")) { if (sesam_execimm ("INSERT INTO mytable VALUES (*, 'Small Test', <0, 8, 15>)") && sesam_execimm ("INSERT INTO othertable VALUES (*, 'Another Test', 1)")) sesam_commit(); else sesam_rollback(); } ?>

sesam_seek_row

(PHP 3 CVS only)

sesam_seek_row -- Set scrollable cursor mode for subsequent fetches

Description

bool sesam_seek_row ( string result_id, int whence [, int offset])

result_id is a valid result id (select type queries only, and only if a "scrollable" cursor was requested when calling sesam_query()).

whence sets the global default value for the scrolling type, it specifies the scroll type to use in subsequent fetch operations on "scrollable" cursors, which can be set to the following predefined constants:

Tabulka 1. Valid values for "whence" parameter

Value	Constant	Meaning
0	`SESAM_SEEK_NEXT`	read sequentially
1	`SESAM_SEEK_PRIOR`	read sequentially backwards
2	`SESAM_SEEK_FIRST`	fetch first row (after fetch, the default is set to `SESAM_SEEK_NEXT`)
3	`SESAM_SEEK_LAST`	fetch last row (after fetch, the default is set to `SESAM_SEEK_PRIOR`)
4	`SESAM_SEEK_ABSOLUTE`	fetch absolute row number given as `offset` (Zero-based. After fetch, the default is set to `SESAM_SEEK_ABSOLUTE`, and the offset value is auto-incremented)
5	`SESAM_SEEK_RELATIVE`	fetch relative to current scroll position, where `offset` can be a positive or negative offset value (this also sets the default "offset" value for subsequent fetches).

offset is an optional parameter which is only evaluated (and required) if whence is either SESAM_SEEK_RELATIVE or SESAM_SEEK_ABSOLUTE.

sesam_settransaction

(PHP 3 CVS only)

sesam_settransaction -- Set SESAM transaction parameters

Description

bool sesam_settransaction ( int isolation_level, int read_only)

Returns: TRUE if the values are valid, and the settransaction() operation was successful, FALSE otherwise.

sesam_settransaction() overrides the default values for the "isolation level" and "read-only" transaction parameters (which are set in the SESAM configuration file), in order to optimize subsequent queries and guarantee database consistency. The overridden values are used for the next transaction only.

sesam_settransaction() can only be called before starting a transaction, not after the transaction has been started already.

To simplify the use in php scripts, the following constants have been predefined in php (see SESAM handbook for detailed explanation of the semantics):

Tabulka 1. Valid values for "Isolation_Level" parameter

Value	Constant	Meaning
1	`SESAM_TXISOL_READ_UNCOMMITTED`	Read Uncommitted
2	`SESAM_TXISOL_READ_COMMITTED`	Read Committed
3	`SESAM_TXISOL_REPEATABLE_READ`	Repeatable Read
4	`SESAM_TXISOL_SERIALIZABLE`	Serializable

Tabulka 2. Valid values for "Read_Only" parameter

Value	Constant	Meaning
0	`SESAM_TXREAD_READWRITE`	Read/Write
1	`SESAM_TXREAD_READONLY`	Read-Only

The values set by sesam_settransaction() will override the default setting specified in the SESAM configuration file.

Příklad 1. Setting SESAM transaction parameters

<?php sesam_settransaction (SESAM_TXISOL_REPEATABLE_READ, SESAM_TXREAD_READONLY); ?>

XCII. Session handling functions

Session support in PHP consists of a way to preserve certain data across subsequent accesses. This enables you to build more customized applications and increase the appeal of your web site.

If you are familiar with the session management of PHPLIB, you will notice that some concepts are similar to PHP's session support.

A visitor accessing your web site is assigned an unique id, the so-called session id. This is either stored in a cookie on the user side or is propagated in the URL.

The session support allows you to register arbitrary numbers of variables to be preserved across requests. When a visitor accesses your site, PHP will check automatically (if session.auto_start is set to 1) or on your request (explicitly through session_start() or implicitly through session_register()) whether a specific session id has been sent with the request. If this is the case, the prior saved environment is recreated.

All registered variables are serialized after the request finishes. Registered variables which are undefined are marked as being not defined. On subsequent accesses, these are not defined by the session module unless the user defines them later.

The track_vars and register_globals configuration settings influence how the session variables get stored and restored.

Poznámka: As of PHP 4.0.3, track_vars is always turned on.

Poznámka: As of PHP 4.1.0, $_SESSION is available as global variable just like $_POST, $_GET, $_REQUEST and so on. Not like $HTTP_SESSION_VARS, $_SESSION is always global. Therefore, global should not be used for $_SESSION.

If track_vars is enabled and register_globals is disabled, only members of the global associative array $HTTP_SESSION_VARS can be registered as session variables. The restored session variables will only be available in the array $HTTP_SESSION_VARS.

Příklad 1. Registering a variable with track_vars enabled

<?php session_start(); if (isset($HTTP_SESSION_VARS['count'])) { $HTTP_SESSION_VARS['count']++; } else { $HTTP_SESSION_VARS['count'] = 0; } ?>

Use of $_SESSION (or $HTTP_SESSION_VARS with PHP 4.0.6 or less) is recommended for security and code readablity. With $_SESSION or $HTTP_SESSION_VARS, there is no need to use session_register()/session_unregister()/session_is_registered() functions. Users can access session variable like a normal variable.

Příklad 2. Registering a variable with $_SESSION.

<?php session_start(); // Use $HTTP_SESSION_VARS with PHP 4.0.6 or less if (!isset($_SESSION['count'])) { $_SESSION['count'] = 0; } else { $_SESSION['count']++; } ?>

Příklad 3. Unregistering a variable with $_SESSION.

<?php session_start(); // Use $HTTP_SESSION_VARS with PHP 4.0.6 or less unset($_SESSION['count']); ?>

If register_globals is enabled, then all global variables can be registered as session variables and the session variables will be restored to corresponding global variables. Since PHP must know which global variables are registered as session variables, users must register variables with session_register() function while $HTTP_SESSION_VARS/$_SESSION does not need to use session_register().

Výstraha

If you are using $HTTP_SESSION_VARS/$_SESSION and disable register_globals, do not use session_register(), session_is_registered() and session_unregister().

If you enable register_globals, session_unregister() should be used since session variables are registered as global variables when session data is deserialized. Disabling register_globals is recommended for both security and performance reason.

Příklad 4. Registering a variable with register_globals enabled

<?php
if (!session_is_registered('count')) {
    session_register("count");
    $count = 0;
}
else {
    $count++;
}
?>

If both track_vars and register_globals are enabled, then the globals variables and the $HTTP_SESSION_VARS/$_SESSION entries will reference the same value for already registered variables.

If user use session_register() to register session variable, $HTTP_SESSION_VARS/$_SESSION will not have these variable in array until it is loaded from session storage. (i.e. until next request)

There are two methods to propagate a session id:

Cookies
URL parameter

The session module supports both methods. Cookies are optimal, but since they are not reliable (clients are not bound to accept them), we cannot rely on them. The second method embeds the session id directly into URLs.

PHP is capable of doing this transparently when compiled with --enable-trans-sid. If you enable this option, relative URIs will be changed to contain the session id automatically. Alternatively, you can use the constant SID which is defined, if the client did not send the appropriate cookie. SID is either of the form session_name=session_id or is an empty string.

Poznámka: The arg_separator.output php.ini directive allows to customize the argument seperator.

The following example demonstrates how to register a variable, and how to link correctly to another page using SID.

Příklad 5. Counting the number of hits of a single user

<?php if (!session_is_registered('count')) { session_register('count'); $count = 1; } else { $count++; } ?> Hello visitor, you have seen this page <?php echo $count; ?> times.<p>; <?php # the <?php echo SID?> (<?=SID?> can be used if short tag is enabled) # is necessary to preserve the session id # in the case that the user has disabled cookies ?> To continue, <A HREF="nextpage.php?<?php echo SID?>">click here</A>

The <?=SID?> is not necessary, if --enable-trans-sid was used to compile PHP.

Poznámka: Non-relative URLs are assumed to point to external sites and hence don't append the SID, as it would be a security risk to leak the SID to a different server.

To implement database storage, or any other storage method, you will need to use session_set_save_handler() to create a set of user-level storage functions.

The session management system supports a number of configuration options which you can place in your php.ini file. We will give a short overview.

session.save_handler defines the name of the handler which is used for storing and retrieving data associated with a session. Defaults to files.

session.save_path defines the argument which is passed to the save handler. If you choose the default files handler, this is the path where the files are created. Defaults to /tmp. If session.save_path's path depth is more than 2, garbage collection will not be performed.

Varování

If you leave this set to a world-readable directory, such as /tmp (the default), other users on the server may be able to hijack sessions by getting the list of files in that directory.

session.name specifies the name of the session which is used as cookie name. It should only contain alphanumeric characters. Defaults to PHPSESSID.
session.auto_start specifies whether the session module starts a session automatically on request startup. Defaults to 0 (disabled).
session.cookie_lifetime specifies the lifetime of the cookie in seconds which is sent to the browser. The value 0 means "until the browser is closed." Defaults to 0.
session.serialize_handler defines the name of the handler which is used to serialize/deserialize data. Currently, a PHP internal format (name php) and WDDX is supported (name wddx). WDDX is only available, if PHP is compiled with WDDX support. Defaults to php.
session.gc_probability specifies the probability that the gc (garbage collection) routine is started on each request in percent. Defaults to 1.
session.gc_maxlifetime specifies the number of seconds after which data will be seen as 'garbage' and cleaned up.
session.referer_check contains the substring you want to check each HTTP Referer for. If the Referer was sent by the client and the substring was not found, the embedded session id will be marked as invalid. Defaults to the empty string.
session.entropy_file gives a path to an external resource (file) which will be used as an additional entropy source in the session id creation process. Examples are /dev/random or /dev/urandom which are available on many Unix systems.
session.entropy_length specifies the number of bytes which will be read from the file specified above. Defaults to 0 (disabled).
session.use_cookies specifies whether the module will use cookies to store the session id on the client side. Defaults to 1 (enabled).
session.use_only_cookies specifies whether the module will only use cookies to store the session id on the client side. Defaults to 0 (disabled, for backward compatibility). Enabling this setting prevents attacks involved passing session ids in URLs. This setting was added in PHP 4.3.0.
session.cookie_path specifies path to set in session_cookie. Defaults to /.
session.cookie_domain specifies domain to set in session_cookie. Default is none at all.
session.cache_limiter specifies cache control method to use for session pages (none/nocache/private/private_no_expire/public). Defaults to nocache.
session.cache_expire specifies time-to-live for cached session pages in minutes, this has no effect for nocache limiter. Defaults to 180.
session.use_trans_sid whether transparent sid support is enabled or not if enabled by compiling with --enable-trans-sid. Defaults to 1 (enabled).
url_rewriter.tags spefifies which html tags are rewritten to include session id if transparent sid support is enabled. Defaults to a=href,area=href,frame=src,input=src,form=fakeentry

Poznámka: Session handling was added in PHP 4.0.

Obsah
session_cache_expire -- Return current cache expire
session_cache_limiter -- Get and/or set the current cache limiter
session_decode -- Decodes session data from a string
session_destroy -- Destroys all data registered to a session
session_encode -- Encodes the current session data as a string
session_get_cookie_params -- Get the session cookie parameters
session_id -- Get and/or set the current session id
session_is_registered -- Find out if a variable is registered in a session
session_module_name -- Get and/or set the current session module
session_name -- Get and/or set the current session name
session_readonly -- Begin session - reinitializes freezed variables, but no writeback on request end
session_register -- Register one or more variables with the current session
session_save_path -- Get and/or set the current session save path
session_set_cookie_params -- Set the session cookie parameters
session_set_save_handler -- Sets user-level session storage functions
session_start -- Initialize session data
session_unregister -- Unregister a variable from the current session
session_unset -- Free all session variables
session_write_close -- Write session data and end session

session_cache_expire

(PHP 4 >= 4.2.0)

session_cache_expire -- Return current cache expire

Description

int session_cache_expire ( [int new_cache_expire])

session_cache_expire() returns current cache expire. If new_cache_expire is given, the current cache expire is replaced with new_cache_expire.

session_cache_limiter

(PHP 4 >= 4.0.3)

session_cache_limiter -- Get and/or set the current cache limiter

Description

string session_cache_limiter ( [string cache_limiter])

session_cache_limiter() returns the name of the current cache limiter. If cache_limiter is specified, the name of the current cache limiter is changed to the new value.

The cache limiter controls the cache control HTTP headers sent to the client. These headers determine the rules by which the page content may be cached. Setting the cache limiter to nocache, for example, would disallow any client-side caching. A value of public, however, would permit caching. It can also be set to private, which is slightly more restrictive than public.

In private mode, Expire header sent to the client, may cause confusion for some browser including Mozilla. You can avoid this problem with private_no_expire mode. Expire header is never sent to the client in this mode.

Poznámka: private_no_expire was added in PHP 4.2.0dev.

The cache limiter is reset to the default value stored in session.cache_limiter at request startup time. Thus, you need to call session_cache_limiter() for every request (and before session_start() is called).

Příklad 1. session_cache_limiter() examples

<?php

# set the cache limiter to 'private'

session_cache_limiter('private');
$cache_limiter = session_cache_limiter();

echo "The cache limiter is now set to $cache_limiter<p>";
?>

Description

array session_get_cookie_params ( void)

The session_get_cookie_params() function returns an array with the current session cookie information, the array contains the following items:

"lifetime" - The lifetime of the cookie.
"path" - The path where information is stored.
"domain" - The domain of the cookie.
"secure" - The cookie should only be sent over secure connections. (This item was added in PHP 4.0.4.)

session_id

(PHP 4 )

session_id -- Get and/or set the current session id

Description

string session_id ( [string id])

session_id() returns the session id for the current session.

If id is specified, it will replace the current session id. session_id() needs to be called before session_start() for that purpose. Depending on the session handler, not all characters are allowed within the session id. For example, the file session handler only allows characters in the range a-z, A-Z and 0-9!

The constant SID can also be used to retrieve the current name and session id as a string suitable for adding to URLs. Note that SID is only defined if the client didn't sent the right cookie. See also Session handling.

session_is_registered

(PHP 4 )

session_is_registered -- Find out if a variable is registered in a session

Description

bool session_is_registered ( string name)

session_is_registered() returns TRUE if there is a variable with the name name registered in the current session.

Poznámka: If $_SESSION (or $HTTP_SESSION_VARS for PHP 4.0.6 or less) is used, use isset() to check a variable is registered in $_SESSION.

Výstraha

If you are using $_SESSION (or $HTTP_SESSION_VARS), do not use session_register(), session_is_registered() and session_unregister().

session_module_name

(PHP 4 )

session_module_name -- Get and/or set the current session module

Description

string session_module_name ( [string module])

session_module_name() returns the name of the current session module. If module is specified, that module will be used instead.

session_name

(PHP 4 )

session_name -- Get and/or set the current session name

Description

string session_name ( [string name])

session_name() returns the name of the current session. If name is specified, the name of the current session is changed to its value.

The session name references the session id in cookies and URLs. It should contain only alphanumeric characters; it should be short and descriptive (i.e. for users with enabled cookie warnings). The session name is reset to the default value stored in session.name at request startup time. Thus, you need to call session_name() for every request (and before session_start() or session_register() are called).

Příklad 1. session_name() examples

<?php

// set the session name to WebsiteID

$previous_name = session_name("WebsiteID");

echo "The previous session name was $previous_name<p>";
?>

session_readonly

(unknown)

session_readonly -- Begin session - reinitializes freezed variables, but no writeback on request end

Description

void session_readonly ( void)

Read in session data without locking the session data. Changing session data is not possible, but frameset performance will be improved.

session_register

(PHP 4 )

session_register -- Register one or more variables with the current session

Description

bool session_register ( mixed name [, mixed ...])

session_register() accepts a variable number of arguments, any of which can be either a string holding the name of a variable or an array consisting of variable names or other arrays. For each name, session_register() registers the global variable with that name in the current session.

Výstraha

This registers a global variable. If you want to register a session variable inside a function, you need to make sure to make it global using global() or use the session arrays as noted below.

Výstraha

If you are using $_SESSION (or $HTTP_SESSION_VARS), do not use session_register(), session_is_registered() and session_unregister().

This function returns TRUE when all of the variables are successfully registered with the session.

If session_start() was not called before this function is called, an implicit call to session_start() with no parameters will be made.

You can also create a session variable by simply setting the appropriate member of the $_SESSION or $HTTP_SESSION_VARS (PHP < 4.1.0) array.

$barney = "A big purple dinosaur.";
session_register("barney");

$_SESSION["zim"] = "An invader from another planet.";

# The old way was to use $HTTP_SESSION_VARS
$HTTP_SESSION_VARS["spongebob"] = "He's got square pants.";

Poznámka: It is not currently possible to register resource variables in a session. For example, you can not create a connection to a database and store the connection id as a session variable and expect the connection to still be valid the next time the session is restored. PHP functions that return a resource are identified by having a return type of resource in their function definitions. A list of functions that return resources are available in the resource types appendix.

If $_SESSION (or $HTTP_SESSION_VARS for PHP 4.0.6 or less) is used, assign variable to $_SESSION. i.e. $_SESSION['var'] = 'ABC';

session_save_path

(PHP 4 )

session_save_path -- Get and/or set the current session save path

Description

string session_save_path ( [string path])

session_save_path() returns the path of the current directory used to save session data. If path is specified, the path to which data is saved will be changed.

Poznámka: On some operating systems, you may want to specify a path on a filesystem that handles lots of small files efficiently. For example, on Linux, reiserfs may provide better performance than ext2fs.

session_set_cookie_params

(PHP 4 )

session_set_cookie_params -- Set the session cookie parameters

Description

void session_set_cookie_params ( int lifetime [, string path [, string domain [, bool secure]]])

Set cookie parameters defined in the php.ini file. The effect of this function only lasts for the duration of the script.

Poznámka: The secure parameter was added in PHP 4.0.4.

session_set_save_handler

(PHP 4 )

session_set_save_handler -- Sets user-level session storage functions

Description

bool session_set_save_handler ( string open, string close, string read, string write, string destroy, string gc)

session_set_save_handler() sets the user-level session storage functions which are used for storing and retrieving data associated with a session. This is most useful when a storage method other than those supplied by PHP sessions is preferred. i.e. Storing the session data in a local database. Vrací TRUE při úspěchu, FALSE při selhání.

Poznámka: You must set the configuration option session.save_handler to user in your php.ini file for session_set_save_handler() to take effect.

Poznámka: The "write" handler is not executed until after the output stream is closed. Thus, output from debugging statements in the "write" handler will never be seen in the browser. If debugging output is necessary, it is suggested that the debug output be written to a file instead.

Poznámka: The write handler is not executed if the session contains no data; this applies even if empty session variables are registered. This differs to the default file-based session save handler, which creates empty session files.

The following example provides file based session storage similar to the PHP sessions default save handler files. This example could easily be extended to cover database storage using your favorite PHP supported database engine.

Read function must return string value always to make save handler work as expected. Return empty string if there is no data to read. Return values from other handlers are converted to boolean expression. TRUE for success, FALSE for failure.

Příklad 1. session_set_save_handler() example

<?php function open ($save_path, $session_name) { global $sess_save_path, $sess_session_name; $sess_save_path = $save_path; $sess_session_name = $session_name; return(true); } function close() { return(true); } function read ($id) { global $sess_save_path, $sess_session_name; $sess_file = "$sess_save_path/sess_$id"; if ($fp = @fopen($sess_file, "r")) { $sess_data = fread($fp, filesize($sess_file)); return($sess_data); } else { return(""); // Must return "" here. } } function write ($id, $sess_data) { global $sess_save_path, $sess_session_name; $sess_file = "$sess_save_path/sess_$id"; if ($fp = @fopen($sess_file, "w")) { return(fwrite($fp, $sess_data)); } else { return(false); } } function destroy ($id) { global $sess_save_path, $sess_session_name; $sess_file = "$sess_save_path/sess_$id"; return(@unlink($sess_file)); } /********************************************* * WARNING - You will need to implement some * * sort of garbage collection routine here. * *********************************************/ function gc ($maxlifetime) { return true; } session_set_save_handler ("open", "close", "read", "write", "destroy", "gc"); session_start(); // proceed to use sessions normally ?>

session_start

(PHP 4 )

session_start -- Initialize session data

Description

bool session_start ( void)

session_start() creates a session (or resumes the current one based on the session id being passed via a GET variable or a cookie).

If you want to use a named session, you must call session_name() before calling session_start().

This function always returns TRUE.

Poznámka: If you are using cookie-based sessions, you must call session_start() before anything is output to the browser.

session_start() will register internal output handler for URL rewriting when trans-sid is enabled. If a user uses ob_gzhandler or like with ob_start(), the order of output handler is important for proper output. For example, user must register ob_gzhandler before session start.

Poznámka: Use of zlib.output_compression is recommended rather than ob_gzhandler

session_unregister

(PHP 4 )

session_unregister -- Unregister a variable from the current session

Description

bool session_unregister ( string name)

session_unregister() unregisters (forgets) the global variable named name from the current session.

This function returns TRUE when the variable is successfully unregistered from the session.

Poznámka: If $_SESSION (or $HTTP_SESSION_VARS for PHP 4.0.6 or less) is used, use unset() to unregister a session variable.

Výstraha

This function doesn't unset the corresponding global variable for name, it only prevents the variable from being saved as part of the session. You must call unset() to remove the corresponding global variable.

Výstraha

If you are using $_SESSION (or $HTTP_SESSION_VARS), do not use session_register(), session_is_registered() and session_unregister().

session_unset

(PHP 4 )

session_unset -- Free all session variables

Description

void session_unset ( void)

The session_unset() function frees all session variables currently registered.

Poznámka: If $_SESSION (or $HTTP_SESSION_VARS for PHP 4.0.6 or less) is used, use unset() to unregister session variable. i.e. $_SESSION = array();

session_write_close

(PHP 4 >= 4.0.4)

session_write_close -- Write session data and end session

Description

void session_write_close ( void)

End the current session and store session data.

Session data is usually stored after your script terminated without the need to call session_write_close(), but as session data is locked to prevent concurrent writes only one script may operate on a session at any time. When using framesets together with sessions you will experience the frames loading one by one due to this locking. You can reduce the time needed to load all the frames by ending the session as soon as all changes to session variables are done.

XCIII. Funkce pro práci se sdílenou pamětí

Shmop snadno použitelná sada funkcí, která PHP umožňuje číst, zapisovat, vytvářet a mazat segmenty UNIXové sdílené paměti. Tyto funkce na Windows nefungují, protože tento systém nepodporuje sdílenou paměť. Pokud chcete shmop používat, budete muset PHP zkompilovat s --enable-shmop.

Poznámka: Názvy funkcí popisovaných v této kapitole začínají v PHP 4.0.3 na shm_(), ale od PHP 4.0.4 se jejich názvy změnily na shmop_().

Příklad 1. Přehled operací se sdílenou pamětí

<?php // Vytvořit 100 bytový blok sdílené paměti se system id 0xff3 $shm_id = shmop_open(0xff3, "c", 0644, 100); if(!$shm_id) { echo "Nepodařilo se vytvořit segment sdílené paměti\n"; } // Zjistit velikost bloku sdílené paměti $shm_size = shmop_size($shm_id); echo "SHM blok o velikosti : ".$shm_size. " byl vytvořen.\n"; // Zapíšeme do sdílené paměti zkušební řetězec $shm_bytes_written = shmop_write($shm_id, "my shared memory block", 0); if($shm_bytes_written != strlen("můj blok sdílené paměti")) { echo "Nepodařilo se zapsat kompletní data\n"; } // Načteme řetězec zpátky $my_string = shmop_read($shm_id, 0, $shm_size); if(!$my_string) { echo "Nepodařilo se číst z bloku sdílené paměti\n"; } echo "Data ve sdílené paměti byla: ".$my_string."\n"; //Smažeme tento blok a zavřeme segment sdílené paměti if(!shmop_delete($shm_id)) { echo "Nepodařilo se smazat blok sdílené paměti."; } shmop_close($shm_id); ?>

Obsah
shmop_close -- Zavřít blok sdílené paměti
shmop_delete -- Smazat blok sdílené paměti
shmop_open -- Vytvořit nebo otevřít blok sdílené paměti
shmop_read -- Přečíst data z bloku sdílené paměti
shmop_size -- Get size of shared memory block
shmop_write -- Zapsat data do bloku sdílené paměti

Poznámka: Pozn.: Pokud otvíráte existující segment paměti, 3. 4. argument by měly být předány jako 0. Při úspěchu shmop_open() vrací id, které můžete použít k přístupu na tento segment sdílené paměti.

Příklad 1. Zápis do bloku sdílené paměti

<?php $shm_bytes_written = shmop_write($shm_id, $my_string, 0); ?>

Tato ukázka zapíše data obsažená v $my_string do bloku sdílené paměti, a $shm_bytes_written obsahuje počet zapsaných bytů.

XCIV. Shockwave Flash functions

PHP offers the ability to create Shockwave Flash files via Paul Haeberli's libswf module. You can download libswf at ftp://ftp.sgi.com/sgi/graphics/grafica/flash. Once you have libswf all you need to do is to configure --with-swf[=DIR] where DIR is a location containing the directories include and lib. The include directory has to contain the swf.h file and the lib directory has to contain the libswf.a file. If you unpack the libswf distribution the two files will be in one directory. Consequently you will have to copy the files to the proper location manually.

Once you've successfully installed PHP with Shockwave Flash support you can then go about creating Shockwave files from PHP. You would be surprised at what you can do, take the following code:

Příklad 1. SWF example

<?php swf_openfile ("test.swf", 256, 256, 30, 1, 1, 1); swf_ortho2 (-100, 100, -100, 100); swf_defineline (1, -70, 0, 70, 0, .2); swf_definerect (4, 60, -10, 70, 0, 0); swf_definerect (5, -60, 0, -70, 10, 0); swf_addcolor (0, 0, 0, 0); swf_definefont (10, "Mod"); swf_fontsize (5); swf_fontslant (10); swf_definetext (11, "This be Flash wit PHP!", 1); swf_pushmatrix (); swf_translate (-50, 80, 0); swf_placeobject (11, 60); swf_popmatrix (); for ($i = 0; $i < 30; $i++) { $p = $i/(30-1); swf_pushmatrix (); swf_scale (1-($p*.9), 1, 1); swf_rotate (60*$p, 'z'); swf_translate (20+20*$p, $p/1.5, 0); swf_rotate (270*$p, 'z'); swf_addcolor ($p, 0, $p/1.2, -$p); swf_placeobject (1, 50); swf_placeobject (4, 50); swf_placeobject (5, 50); swf_popmatrix (); swf_showframe (); } for ($i = 0; $i < 30; $i++) { swf_removeobject (50); if (($i%4) == 0) { swf_showframe (); } } swf_startdoaction (); swf_actionstop (); swf_enddoaction (); swf_closefile (); ?>

Poznámka: SWF support was added in PHP 4 RC2.

The libswf does not have support for Windows. The development of that library has been stopped, and the source is not available to port it to another systems.

For up to date SWF support take a look at the MING functions.

Obsah
swf_actiongeturl -- Get a URL from a Shockwave Flash movie
swf_actiongotoframe -- Play a frame and then stop
swf_actiongotolabel -- Display a frame with the specified label
swf_actionnextframe -- Go foward one frame
swf_actionplay -- Start playing the flash movie from the current frame
swf_actionprevframe -- Go backwards one frame
swf_actionsettarget -- Set the context for actions
swf_actionstop -- Stop playing the flash movie at the current frame
swf_actiontogglequality -- Toggle between low and high quality
swf_actionwaitforframe -- Skip actions if a frame has not been loaded
swf_addbuttonrecord -- Controls location, appearance and active area of the current button
swf_addcolor -- Set the global add color to the rgba value specified
swf_closefile -- Close the current Shockwave Flash file
swf_definebitmap -- Define a bitmap
swf_definefont -- Defines a font
swf_defineline -- Define a line
swf_definepoly -- Define a polygon
swf_definerect -- Define a rectangle
swf_definetext -- Define a text string
swf_endbutton -- End the definition of the current button
swf_enddoaction -- End the current action
swf_endshape -- Completes the definition of the current shape
swf_endsymbol -- End the definition of a symbol
swf_fontsize -- Change the font size
swf_fontslant -- Set the font slant
swf_fonttracking -- Set the current font tracking
swf_getbitmapinfo -- Get information about a bitmap
swf_getfontinfo -- The height in pixels of a capital A and a lowercase x
swf_getframe -- Get the frame number of the current frame
swf_labelframe -- Label the current frame
swf_lookat -- Define a viewing transformation
swf_modifyobject -- Modify an object
swf_mulcolor -- Sets the global multiply color to the rgba value specified
swf_nextid -- Returns the next free object id
swf_oncondition -- Describe a transition used to trigger an action list
swf_openfile -- Open a new Shockwave Flash file
swf_ortho2 -- Defines 2D orthographic mapping of user coordinates onto the current viewport
swf_ortho -- Defines an orthographic mapping of user coordinates onto the current viewport
swf_perspective -- Define a perspective projection transformation
swf_placeobject -- Place an object onto the screen
swf_polarview -- Define the viewer's position with polar coordinates
swf_popmatrix -- Restore a previous transformation matrix
swf_posround -- Enables or Disables the rounding of the translation when objects are placed or moved
swf_pushmatrix -- Push the current transformation matrix back unto the stack
swf_removeobject -- Remove an object
swf_rotate -- Rotate the current transformation
swf_scale -- Scale the current transformation
swf_setfont -- Change the current font
swf_setframe -- Switch to a specified frame
swf_shapearc -- Draw a circular arc
swf_shapecurveto3 -- Draw a cubic bezier curve
swf_shapecurveto -- Draw a quadratic bezier curve between two points
swf_shapefillbitmapclip -- Set current fill mode to clipped bitmap
swf_shapefillbitmaptile -- Set current fill mode to tiled bitmap
swf_shapefilloff -- Turns off filling
swf_shapefillsolid -- Set the current fill style to the specified color
swf_shapelinesolid -- Set the current line style
swf_shapelineto -- Draw a line
swf_shapemoveto -- Move the current position
swf_showframe -- Display the current frame
swf_startbutton -- Start the definition of a button
swf_startdoaction -- Start a description of an action list for the current frame
swf_startshape -- Start a complex shape
swf_startsymbol -- Define a symbol
swf_textwidth -- Get the width of a string
swf_translate -- Translate the current transformations
swf_viewport -- Select an area for future drawing

swf_closefile

(PHP 4 )

swf_closefile -- Close the current Shockwave Flash file

Description

array swf_getbitmapinfo ( int bitmapid)

The swf_getbitmapinfo() function returns an array of information about a bitmap given by the bitmapid parameter. The returned array has the following elements:

"size" - The size in bytes of the bitmap.
"width" - The width in pixels of the bitmap.
"height" - The height in pixels of the bitmap.

swf_getfontinfo

(PHP 4 )

swf_getfontinfo -- The height in pixels of a capital A and a lowercase x

Description

array swf_getfontinfo ( void)

The swf_getfontinfo() function returns an associative array with the following parameters:

Aheight - The height in pixels of a capital A.
xheight - The height in pixels of a lowercase x.

MOD_COLOR uses the current mulcolor (specified by the function swf_mulcolor()) and addcolor (specified by the function swf_addcolor()) to color the object. MOD_MATRIX uses the current matrix to position the object.

swf_mulcolor

(PHP 4 )

swf_mulcolor -- Sets the global multiply color to the rgba value specified

Description

void swf_mulcolor ( float r, float g, float b, float a)

The swf_mulcolor() function sets the global multiply color to the rgba color specified. This color is then used (implicitly) by the swf_placeobject(), swf_modifyobject() and the swf_addbuttonrecord() functions. The color of the object will be multiplied by the rgba values when the object is written to the screen.

Poznámka: The rgba values can be either positive or negative.

swf_nextid

void swf_openfile ( string filename, float width, float height, float framerate, float r, float g, float b)

void swf_perspective ( float fovy, float aspect, float near, float far)

The swf_perspective() function defines a perspective projection transformation. The fovy parameter is field-of-view angle in the y direction. The aspect parameter should be set to the aspect ratio of the viewport that is being drawn onto. The near parameter is the near clipping plane and the far parameter is the far clipping plane.

Poznámka: Various distortion artifacts may appear when performing a perspective projection, this is because Flash players only have a two dimensional matrix. Some are not to pretty.

swf_placeobject

(PHP 4 )

swf_placeobject -- Place an object onto the screen

Description

void swf_placeobject ( int objid, int depth)

Places the object specified by objid in the current frame at a depth of depth. The objid parameter and the depth must be between 1 and 65535.

This uses the current mulcolor (specified by swf_mulcolor()) and the current addcolor (specified by swf_addcolor()) to color the object and it uses the current matrix to position the object.

Poznámka: Full RGBA colors are supported.

XCV. SNMP functions

In order to use the SNMP functions on Unix you need to install the UCD SNMP package. On Windows these functions are only available on NT and not on Win95/98.

Important: In order to use the UCD SNMP package, you need to define NO_ZEROLENGTH_COMMUNITY to 1 before compiling it. After configuring UCD SNMP, edit config.h and search for NO_ZEROLENGTH_COMMUNITY. Uncomment the #define line. It should look like this afterwards:

#define NO_ZEROLENGTH_COMMUNITY 1

If you see strange segmentation faults in combination with SNMP commands, you did not follow the above instructions. If you do not want to recompile UCD SNMP, you can compile PHP with the --enable-ucd-snmp-hack switch which will work around the misfeature.

Obsah
snmp_get_quick_print -- Fetch the current value of the UCD library's quick_print setting
snmp_set_quick_print -- Set the value of quick_print within the UCD SNMP library
snmpget -- Fetch an SNMP object
snmprealwalk -- Return all objects including their respective object ID within the specified one
snmpset -- Set an SNMP object
snmpwalk -- Fetch all the SNMP objects from an agent
snmpwalkoid -- Query for a tree of information about a network entity

snmp_get_quick_print

(PHP 3>= 3.0.8, PHP 4 )

snmp_get_quick_print -- Fetch the current value of the UCD library's quick_print setting

Description

bool snmp_get_quick_print ( void)

Returns the current value stored in the UCD Library for quick_print. quick_print is off by default.

$quickprint = snmp_get_quick_print();

Above function call would return FALSE if quick_print is off, and TRUE if quick_print is on.

snmp_get_quick_print() is only available when using the UCD SNMP library. This function is not available when using the Windows SNMP library.

See: snmp_set_quick_print() for a full description of what quick_print does.

snmp_set_quick_print

(PHP 3>= 3.0.8, PHP 4 )

snmp_set_quick_print -- Set the value of quick_print within the UCD SNMP library

Description

void snmp_set_quick_print ( bool quick_print)

Sets the value of quick_print within the UCD SNMP library. When this is set (1), the SNMP library will return 'quick printed' values. This means that just the value will be printed. When quick_print is not enabled (default) the UCD SNMP library prints extra information including the type of the value (i.e. IpAddress or OID). Additionally, if quick_print is not enabled, the library prints additional hex values for all strings of three characters or less.

Setting quick_print is often used when using the information returned rather then displaying it.

snmp_set_quick_print(0);
$a = snmpget("127.0.0.1", "public", ".1.3.6.1.2.1.2.2.1.9.1");
echo "$a<BR>\n";
snmp_set_quick_print(1);
$a = snmpget("127.0.0.1", "public", ".1.3.6.1.2.1.2.2.1.9.1");
echo "$a<BR>\n";

The first value printed might be: 'Timeticks: (0) 0:00:00.00', whereas with quick_print enabled, just '0:00:00.00' would be printed.

By default the UCD SNMP library returns verbose values, quick_print is used to return only the value.

Currently strings are still returned with extra quotes, this will be corrected in a later release.

snmp_set_quick_print() is only available when using the UCD SNMP library. This function is not available when using the Windows SNMP library.

snmpget

(PHP 3, PHP 4 )

snmpget -- Fetch an SNMP object

Description

string snmpget ( string hostname, string community, string object_id [, int timeout [, int retries]])

Returns SNMP object value on success and FALSE on error.

The snmpget() function is used to read the value of an SNMP object specified by the object_id. SNMP agent is specified by the hostname and the read community is specified by the community parameter.

$syscontact = snmpget("127.0.0.1", "public", "system.SysContact.0");

$a = snmpwalk("127.0.0.1", "public", "");

Above function call would return all the SNMP objects from the SNMP agent running on localhost. One can step through the values with a loop

for ($i=0; $i < count($a); $i++) {
    echo $a[$i];
}

snmpwalkoid

(PHP 3>= 3.0.8, PHP 4 )

snmpwalkoid -- Query for a tree of information about a network entity

Description

array snmpwalkoid ( string hostname, string community, string object_id [, int timeout [, int retries]])

Returns an associative array with object ids and their respective object value starting from the object_id as root and FALSE on error.

snmpwalkoid() function is used to read all object ids and their respective values from an SNMP agent specified by the hostname. Community specifies the read community for that agent. A NULL object_id is taken as the root of the SNMP objects tree and all objects under that tree are returned as an array. If object_id is specified, all the SNMP objects below that object_id are returned.

The existence of snmpwalkoid() and snmpwalk() has historical reasons. Both functions are provided for backward compatibility.

$a = snmpwalkoid("127.0.0.1", "public", "");

Above function call would return all the SNMP objects from the SNMP agent running on localhost. One can step through the values with a loop

for (reset($a); $i = key($a); next($a)) {
    echo "$i: $a[$i]<br>\n";
}

XCVI. Socket functions

Varování

The socket extension implements a low-level interface to the socket communication functions based on the popular BSD sockets, providing the possibility to act as a socket server as well as a client.

The socket functions described here are part of an extension to PHP which must be enabled at compile time by giving the --enable-sockets option to configure.

For a more generic client-side socket interface, see fsockopen() and pfsockopen().

When using these functions, it is important to remember that while many of them have identical names to their C counterparts, they often have different declarations. Please be sure to read the descriptions to avoid confusion.

The socket extension was written to provide a useable interface to the powerful BSD sockets. Care has been taken that the functions work equally well on Win32 and Unix implementations. Almost all of the sockets functions may fail under certain conditions and therefore emit an E_WARNING message describing the error. Sometimes this doesn't happen to the desire of the developer. For example the function socket_read() may suddenly emit an E_WARNING message because the connection broke unexpectedly. It's common to suppress the warning with the @-operator and catch the error code within the application with the socket_last_error() function. You may call the socket_strerror() function with this error code to retrieve a string describing the error. See their description for more information.

Poznámka: The E_WARNING messages generated by the socket extension are in english though the retrieved error message will appear depending on the current locale (LC_MESSAGES):
Warning - socket_bind() unable to bind address [98]: Die Adresse wird bereits verwendet

That said, those unfamiliar with socket programming can still find a lot of useful material in the appropriate Unix man pages, and there is a great deal of tutorial information on socket programming in C on the web, much of which can be applied, with slight modifications, to socket programming in PHP. The UNIX Socket FAQ might be a good start.

Příklad 1. Socket example: Simple TCP/IP server

This example shows a simple talkback server. Change the address and port variables to suit your setup and execute. You may then connect to the server with a command similar to: telnet 192.168.1.53 10000 (where the address and port match your setup). Anything you type will then be output on the server side, and echoed back to you. To disconnect, enter 'quit'.

#!/usr/local/bin/php -q <?php error_reporting (E_ALL); /* Allow the script to hang around waiting for connections. */ set_time_limit (0); /* Turn on implicit output flushing so we see what we're getting * as it comes in. */ ob_implicit_flush (); $address = '192.168.1.53'; $port = 10000; if (($sock = socket_create (AF_INET, SOCK_STREAM, 0)) < 0) { echo "socket_create() failed: reason: " . socket_strerror ($sock) . "\n"; } if (($ret = socket_bind ($sock, $address, $port)) < 0) { echo "socket_bind() failed: reason: " . socket_strerror ($ret) . "\n"; } if (($ret = socket_listen ($sock, 5)) < 0) { echo "socket_listen() failed: reason: " . socket_strerror ($ret) . "\n"; } do { if (($msgsock = socket_accept($sock)) < 0) { echo "socket_accept() failed: reason: " . socket_strerror ($msgsock) . "\n"; break; } /* Send instructions. */ $msg = "\nWelcome to the PHP Test Server. \n" . "To quit, type 'quit'. To shut down the server type 'shutdown'.\n"; socket_write($msgsock, $msg, strlen($msg)); do { if (FALSE === ($buf = socket_read ($msgsock, 2048))) { echo "socket_read() failed: reason: " . socket_strerror ($ret) . "\n"; break 2; } if (!$buf = trim ($buf)) { continue; } if ($buf == 'quit') { break; } if ($buf == 'shutdown') { socket_close ($msgsock); break 2; } $talkback = "PHP: You said '$buf'.\n"; socket_write ($msgsock, $talkback, strlen ($talkback)); echo "$buf\n"; } while (true); socket_close ($msgsock); } while (true); socket_close ($sock); ?>

Příklad 2. Socket example: Simple TCP/IP client

This example shows a simple, one-shot HTTP client. It simply connects to a page, submits a HEAD request, echoes the reply, and exits.

<?php error_reporting (E_ALL); echo "<h2>TCP/IP Connection</h2>\n"; /* Get the port for the WWW service. */ $service_port = getservbyname ('www', 'tcp'); /* Get the IP address for the target host. */ $address = gethostbyname ('www.example.com'); /* Create a TCP/IP socket. */ $socket = socket_create (AF_INET, SOCK_STREAM, 0); if ($socket < 0) { echo "socket_create() failed: reason: " . socket_strerror ($socket) . "\n"; } else { echo "OK.\n"; } echo "Attempting to connect to '$address' on port '$service_port'..."; $result = socket_connect ($socket, $address, $service_port); if ($result < 0) { echo "socket_connect() failed.\nReason: ($result) " . socket_strerror($result) . "\n"; } else { echo "OK.\n"; } $in = "HEAD / HTTP/1.0\r\n\r\n"; $out = ''; echo "Sending HTTP HEAD request..."; socket_write ($socket, $in, strlen ($in)); echo "OK.\n"; echo "Reading response:\n\n"; while ($out = socket_read ($socket, 2048)) { echo $out; } echo "Closing socket..."; socket_close ($socket); echo "OK.\n\n"; ?>

Obsah
socket_accept -- Accepts a connection on a socket
socket_bind -- Binds a name to a socket
socket_clear_error -- Clears the error on the socket or the last error code
socket_close -- Closes a socket resource
socket_connect -- Initiates a connection on a socket
socket_create_listen -- Opens a socket on port to accept connections
socket_create_pair -- Creates a pair of indistinguishable sockets and stores them in fds.
socket_create -- Create a socket (endpoint for communication)
socket_get_option -- Gets socket options for the socket
socket_getpeername -- Queries the remote side of the given socket which may either result in host/port or in a UNIX filesystem path, dependent on its type.
socket_getsockname -- Queries the local side of the given socket which may either result in host/port or in a UNIX filesystem path, dependent on its type.
socket_iovec_add -- Adds a new vector to the scatter/gather array
socket_iovec_alloc -- ...]) Builds a 'struct iovec' for use with sendmsg, recvmsg, writev, and readv
socket_iovec_delete -- Deletes a vector from an array of vectors
socket_iovec_fetch -- Returns the data held in the iovec specified by iovec_id[iovec_position]
socket_iovec_free -- Frees the iovec specified by iovec_id
socket_iovec_set -- Sets the data held in iovec_id[iovec_position] to new_val
socket_last_error -- Returns the last error on the socket
socket_listen -- Listens for a connection on a socket
socket_read -- Reads a maximum of length bytes from a socket
socket_readv -- Reads from an fd, using the scatter-gather array defined by iovec_id
socket_recv -- Receives data from a connected socket
socket_recvfrom -- Receives data from a socket, connected or not
socket_recvmsg -- Used to receive messages on a socket, whether connection-oriented or not
socket_select -- Runs the select() system call on the given arrays of sockets with a timeout specified by tv_sec and tv_usec
socket_send -- Sends data to a connected socket
socket_sendmsg -- Sends a message to a socket, regardless of whether it is connection-oriented or not
socket_sendto -- Sends a message to a socket, whether it is connected or not
socket_set_nonblock -- Sets nonblocking mode for file descriptor fd
socket_set_option -- Sets socket options for the socket
socket_shutdown -- Shuts down a socket for receiving, sending, or both.
socket_strerror -- Return a string describing a socket error
socket_write -- Write to a socket
socket_writev -- Writes to a file descriptor, fd, using the scatter-gather array defined by iovec_id

socket_accept

(PHP 4 >= 4.1.0)

socket_accept -- Accepts a connection on a socket

Description

resource socket_accept ( resource socket)

Varování

After the socket socket has been created using socket_create(), bound to a name with socket_bind(), and told to listen for connections with socket_listen(), this function will accept incoming connections on that socket. Once a successful connection is made, a new socket resource is returned, which may be used for communication. If there are multiple connections queued on the socket, the first will be used. If there are no pending connections, socket_accept() will block until a connection becomes present. If socket has been made non-blocking using socket_set_blocking() or socket_set_nonblock(), FALSE will be returned.

The socket resource returned by socket_accept() may not be used to accept new connections. The original listening socket socket, however, remains open and may be reused.

Returns a new socket resource on success, or FALSE on error. The actual error code can be retrieved by calling socket_last_error(). This error code may be passed to socket_strerror() to get a textual explanation of the error.

socket_bind

(PHP 4 >= 4.1.0)

socket_bind -- Binds a name to a socket

Description

bool socket_bind ( resource socket, string address [, int port])

Varování

resource socket_create_listen ( int port [, int backlog])

Varování

This function is meant to ease the task of creating a new socket which only listens to accept new connections.

socket_create_listen() create a new socket resource of type AF_INET listening on all local interfaces on the given port waiting for new connections.

The backlog parameter defines the maximum length the queue of pending connections may grow to. SOMAXCONN may be passed as backlog parameter, see socket_listen() for more information.

socket_create_listen() returns a new socket resource on success or FALSE on error. The error code can be retrieved with socket_last_error(). This code may be passed to socket_strerror() to get a textual explanation of the error.

Poznámka: If you want to create a socket which only listens on a certain interfaces you need to use socket_create(), socket_bind() and socket_listen().

socket_create_pair

(PHP 4 >= 4.1.0)

socket_create_pair -- Creates a pair of indistinguishable sockets and stores them in fds.

Description

bool socket_create_pair ( int domain, int type, int protocol, array &fd)

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

socket_create

(PHP 4 >= 4.1.0)

socket_create -- Create a socket (endpoint for communication)

Description

resource socket_create ( int domain, int type, int protocol)

Varování

Creates a communication endpoint (a socket), and returns a socket resource.

The domain parameter sets the domain (protocol family) to be used for communication. Currently, AF_INET and AF_UNIX are understood. AF_INET is typical used for internet based communication. AF_UNIX uses pathnames to identify sockets and can therefore only be used for local communication (which is faster, on the other hand).

The type parameter selects the socket type. This is one of SOCK_STREAM, SOCK_DGRAM, SOCK_SEQPACKET, SOCK_RAW, SOCK_RDM, or SOCK_PACKET. The two most common types are SOCK_DGRAM for UDP (connectionless) communication and SOCK_STREAM for TCP communication.

protocol sets the protocol which is either SOL_UDP or SOL_TCP.

Returns a socket resource on success, or FALSE on error. The actual error code can be retrieved by calling socket_last_error(). This error code may be passed to socket_strerror() to get a textual explanation of the error.

For more information on the usage of socket_create(), as well as on the meanings of the various parameters, see the Unix man page socket (2).

Poznámka: If an invalid domain or type is given, socket_create() defaults to AF_INET and SOCK_STREAM respectively and additionally emits an E_WARNING message.

socket_get_option

(PHP 4 CVS only)

socket_get_option -- Gets socket options for the socket

Description

mixed socket_get_option ( resource socket, int level, int optname)

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

Poznámka: This function used to be called socket_getopt() prior to PHP 4.3.0

socket_getpeername

(PHP 4 >= 4.1.0)

socket_getpeername -- Queries the remote side of the given socket which may either result in host/port or in a UNIX filesystem path, dependent on its type.

Description

bool socket_getpeername ( resource socket, string &addr [, int &port])

Varování

If the given socket is of type AF_INET, socket_getpeername() will return the peers (remote) IP address in dotted-quad notation (e.g. 127.0.0.1) in the address parameter and, if the optional port parameter is present, also the associated port.

If the given socket is of type AF_UNIX, socket_getpeername() will return the UNIX filesystem path (e.g. /var/run/daemon.sock) in the address parameter.

Vrací TRUE při úspěchu, FALSE při selhání. socket_getpeername() may also return FALSE if the socket type is not any of AF_INET or AF_UNIX, in which case the last socket error code is not updated.

See also socket_getpeername(), socket_last_error() and socket_strerror().

socket_getsockname

(PHP 4 >= 4.1.0)

socket_getsockname -- Queries the local side of the given socket which may either result in host/port or in a UNIX filesystem path, dependent on its type.

Description

bool socket_getsockname ( resource socket, string &addr [, int &port])

Varování

int socket_last_error ( [resource socket])

Varování

This function returns a socket error code.

If a socket resource is passed to this function, the last error which occured on this particular socket is returned. If the socket resource is ommited, the error code of the last failed socket function is returned. The latter is in particular helpful for functions like socket_create() which don't return a socket on failure and socket_select() which can fail for reasons not directly tied to a particular socket. The error code is suitable to be fed to socket_strerror() which returns a string describing the given error code.

if (false == ($socket = @socket_create(AF_INET, SOCK_STREAM, SOL_TCP))) { die("Couldn't create socket, error code is: " . socket_last_error() . ",error message is: " . socket_strerror(socket_last_error())); }

Poznámka: socket_last_error() does not clear the error code, use socket_clear_error() for this purpose.

socket_listen

(PHP 4 >= 4.1.0)

socket_listen -- Listens for a connection on a socket

Description

bool socket_listen ( resource socket [, int backlog])

Varování

After the socket socket has been created using socket_create() and bound to a name with socket_bind(), it may be told to listen for incoming connections on socket.

A maximum of backlog incoming connections will be queued for processing. If a connection request arrives with the queue full the client may receive an error with an indication of ECONNREFUSED, or, if the underlying protocol supports retransmission, the request may be ignored so that retries may succeed.

Poznámka: The maximum number passed to the backlog parameter highly depends on the underlying platform. On linux, it is silently truncated to SOMAXCONN. On win32, if passed SOMAXCONN, the underlying service provider responsible for the socket will set the backlog to a maximum reasonable value. There is no standard provision to find out the actual backlog value on this platform.

socket_listen() is applicable only to sockets of type SOCK_STREAM or SOCK_SEQPACKET.

socket_read

(PHP 4 >= 4.1.0)

socket_read -- Reads a maximum of length bytes from a socket

Description

string socket_read ( resource socket, int length [, int type])

Varování

The function socket_read() reads from the socket resource socket created by the socket_create() or socket_accept() functions. The maximum number of bytes read is specified by the length parameter. Otherwise you can use \r, \n, or \0 to end reading (depending on the type parameter, see below).

socket_read() returns the data as a string on success, or FALSE on error. The error code can be retrieved with socket_last_error(). This code may be passed to socket_strerror() to get a textual representation of the error.

Poznámka: socket_read() may return a zero length string ("") indicating the end of communication (i.e. the remote end point has closed the connection).

Optional type parameter is a named constant:

PHP_BINARY_READ - use the system read() function. Safe for reading binary data. (Default in PHP >= 4.1.0)
PHP_NORMAL_READ - reading stops at \n or \r. (Default in PHP <= 4.0.6)

The sockets listed in the read array will be watched to see if characters become available for reading (more precisely, to see if a read will not block - in particular, a socket resource is also ready on end-of-file, in which case a socket_read() will return a zero length string).

The sockets listed in the write array will be watched to see if a write will not block.

The sockets listed in the except array will be watched for exceptions.

Varování

On exit, the arrays are modified to indicate which socket resource actually changed status.

You do not need to pass every array to socket_select(). You can leave it out and use an empty array or NULL instead. Also do not forget that those arrays are passed by reference and will be modified after socket_select() returns.

Example:

/* Prepare the read array */ $read = array($socket1, $socket2); if (false === ($num_changed_sockets = socket_select($read, $write = NULL, $except = NULL, 0))) { /* Error handling */ else if ($num_changed_sockets > 0) { /* At least at one of the sockets something interesting happened */ }

Poznámka: Due a limitation in the current Zend Engine it is not possible to pass a constant modifier like NULL directly as a parameter to a function which expects this parameter to be passed by reference. Instead use a temporary variable or an expression with the leftmost member being a temporary variable:
socket_select($r, $w, $e = NULL, 0);

The tv_sec and tv_usec together form the timeout parameter. The timeout is an upper bound on the amount of time elapsed before socket_select() return. tv_sec may be zero , causing socket_select() to return immediately. This is useful for polling. If tv_sec is NULL (no timeout), socket_select() can block indefinitely.

On success socket_select() returns the number of socket resorces contained in the modified arrays, which may be zero if the timeout expires before anything interesting happens. On error FALSE is returned. The error code can be retrieved with socket_last_error().

Poznámka: Be sure to use the === operator when checking for an error. Since the socket_select() may return 0 the comparison with == would evaluate to TRUE:
if (false === socket_select($r, $w, $e = NULL, 0)) {
    echo "socket_select() failed, reason: " . socket_strerror(socket_last_error()) . "\n";
}

Poznámka: Be aware that some socket implementations need to be handled very carefully. A few basic rules:

You should always try to use socket_select() without timeout. Your program should have nothing to do if there is no data available. Code that depends on timeouts is not usually portable and difficult to debug.

No socket resource must be added to any set if you do not intend to check its result after the socket_select() call, and respond appropriately. After socket_select() returns, all socket resources in all arrays must be checked. Any socket resource that is available for writing must be written to, and any socket resource available for reading must be read from.

If you read/write to a socket returns in the arrays be aware that they do not necessarily read/write the full amount of data you have requested. Be prepared to even only be able to read/write a single byte.

It's common to most socket implementations that the only exception caught with the except array is out-of-bound data received on a socket.

Poznámka: This function used to be called socket_setopt() prior to PHP 4.3.0

socket_shutdown

(PHP 4 >= 4.1.0)

socket_shutdown -- Shuts down a socket for receiving, sending, or both.

Description

bool socket_shutdown ( resource socket [, int how])

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

socket_strerror

(PHP 4 >= 4.1.0)

socket_strerror -- Return a string describing a socket error

Description

string socket_strerror ( int errno)

Varování

socket_strerror() takes as its errno parameter a socket error code as returned by socket_last_error() and returns the corresponding explanatory text. This makes it a bit more pleasant to figure out why something didn't work; for instance, instead of having to track down a system include file to find out what '-111' means, you just pass it to socket_strerror(), and it tells you what happened.

Příklad 1. socket_strerror() example

<?php if (false == ($socket = @socket_create(AF_INET, SOCK_STREAM, 0))) { echo "socket_create() failed: reason: " . socket_strerror(socket_last_error()) . "\n"; } if (false == (@socket_bind($socket, '127.0.0.1', 80))) { echo "socket_bind() failed: reason: " . socket_strerror(socket_last_error($socket)) . "\n"; } ?>

The expected output from the above example (assuming the script is not run with root privileges):

socket_bind() failed: reason: Permission denied

socket_write

(PHP 4 >= 4.1.0)

socket_write -- Write to a socket

Description

int socket_write ( resource socket, string buffer [, int length])

Varování

The function socket_write() writes to the socket socket from buffer.

The optional parameter length can specify an alternate length of bytes written to the socket. If this length is greater then the buffer length, it is silently truncated to the length of the buffer.

Returns the number of bytes successfully written to the socket or FALSE one error. The error code can be retrieved with socket_last_error(). This code may be passed to socket_strerror() to get a textual explanation of the error.

Poznámka: socket_write() does not necessarily write all bytes from the given buffer. It's valid that, depending on the network buffers etc., only a certain amount of data, even one byte, is written though your buffer is greater. You have to watch out so you don't unintentionally forget to transmit the rest of your data.

Poznámka: It is perfectly valid for socket_write() to return zero which means no bytes have been written. Be sure to use the === operator to check for FALSE in case of an error.

socket_writev

(PHP 4 >= 4.1.0)

socket_writev -- Writes to a file descriptor, fd, using the scatter-gather array defined by iovec_id

Description

bool socket_writev ( resource socket, resource iovec_id)

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

XCVII. Funkce pro práci s řetězci

Všechny tyto funkce různými způsoby pracují s řetězci. Některé specializovanější funkce najdete v sekcích regulárních výrazů a obsluha URL.

Informace o chování řetězců, zvláště v souvislosti s použitím jednoduchých uvozovek, dvojitých uvozovek a znaků opatřených zpětnými lomítky, viz položky Řetězce v sekci Typy tohoto manuálu.

Další informace o mnohem mocnějším zacházení s řetězci a obslužnými funkcemi nalezenete v sekcích POSIX funkce pro regulární výrazy a Perl kompatibilní funkce regulárních výrazů.

Obsah
addcslashes -- Opatřit řetězec lomítky ve stylu jazyka C
addslashes -- Opatřit řetězec lomítky
bin2hex -- Převést binární data na hexadecimální reprezentaci
chop -- Odstranit netisknutelné znaky z konce řetězce
chr -- Vrátit určitý znak
chunk_split -- Rozdělit řetězec na menší části
convert_cyr_string -- Převést z jedné znakové sady Azbuky do jiné
count_chars -- Vrátit informace o znacích použitých v řetězci
crc32 -- Spočítat kontrolní součet crc32 řetězce
crypt -- Jednosměrné zašifrování řetězce
echo -- Vytisknout jeden nebo více řetězců
explode -- Rozděluje řetězec jiným řetězcem
get_html_translation_table -- Vrací překladovou tabulku používanou v htmlspecialchars() a htmlentities()
get_meta_tags -- Získá hodnoty content atributů všech meta tagů v souboru a vrátí pole
hebrev -- Převést logický Hebrejský text na vizuální text
hebrevc -- Převést logický Hebrejský text na vizuální text s konverzí konců řádků
htmlentities -- Převést všechny použitelné znaky na HTML entity
htmlspecialchars -- Převést zvláštní znaky na HTML entity
implode -- Spojit prvky pole pomocí řetězce
join -- Spojit prvky pole pomocí řetězce
levenshtein -- Spočítat XXX Levenshteinovu vzdálenost mezi dvěma řetězci
localeconv -- Get numeric formatting information
ltrim -- Odstranit netisknutelné znaky ze začátku řetězce
md5_file -- Calculates the md5 hash of a given filename
md5 -- Spočítat MD5 XXX hash řetězce
metaphone -- Spočítat metaphone klíč řetězce
nl_langinfo -- Query language and locale information
nl2br -- Převede konce řádků na HTML konce řádků
ord -- Vrátit ASCII hodnotu znaku
parse_str -- Roparsovat řetězec do proměnných
print -- Vytisknout řetězec
printf -- Vytisknout formátovaný řetězec
quoted_printable_decode -- Převést quoted-printable řetězec na osmibitový řetězec
quotemeta -- Opatřit lomítky metaznaky
rtrim -- Odstranit netisknutelné znaky z konce řetězce
setlocale -- Set locale information
similar_text -- Spočítat podobnost dvou řetězců
soundex -- Spočítat soundex klíč řetězce
sprintf -- Vrátit formátovaný řetězec
sscanf -- Rozparsovat vstupní řetězec podle formátu
str_pad -- Doplnit řetězec jiným řetězcem na určitou délku
str_repeat -- Opakovat řetězec
str_replace -- Nahradit všechny výskyty jednoho řetězce v jiném dalším řetězcem
str_rot13 -- Perform the rot13 transform on a string
strcasecmp -- Binárně bezpečné case-insensitive porovnání řetězců
strchr -- Najít první výskyt znaku
strcmp -- Binárně bezpečně porovnat řetězce
strcoll -- Locale based string comparison
strcspn -- Najít délku úvodního segmentu neodpovídajícího masce
strip_tags -- Odstranit z řetězce HTML a PHP tagy
stripcslashes -- Un-quote string quoted with addcslashes()
stripslashes -- Un-quote string quoted with addslashes()
stristr -- Case-insensitive strstr()
strlen -- Zjistit délku řetězce
strnatcasecmp -- Case-insensitive textové porovnání s využitím "natural order" algoritmu
strnatcmp -- Porovnání řetězců algoritmem "přirozeného třídění"
strncasecmp -- Binárně bezpečné case-insensitive porovnání prvních n znaků řetězců
strncmp -- Binárně bezpečné porovnání prvních n znaků v řetězcích
strpos -- Najít pozici prvního výskytu řetězce
strrchr -- Najít poslední výskyt znaku v řetězci
strrev -- Obrátit řetězec
strrpos -- Najít pozici posledního výskytu znaku v řetězci
strspn -- Zjistit délku úvodního segmentu odpovídajícího masce
strstr -- Najít první výskyt řetězce
strtok -- Tokenize string
strtolower -- Změnit řetězec na malá písmena
strtoupper -- Změnit řetězec na velká písmena
strtr -- Přeložit určité znaky
substr_count -- Spočítat počet výskytů řetězce
substr_replace -- Nahradit část řetězce jiným řetězcem
substr -- Vrátit část řetězce
trim -- Odstranit netisknutelné znaky ze začátku a konce řetězce
ucfirst -- Změní první písmeno řetězce na velké
ucwords -- Změnit první znak každého slova v řetězci na velké písmeno
vprintf -- Output a formatted string
vsprintf -- Return a formatted string
wordwrap -- Zalámat řetězec na daný počet znaků pomocí break znaku

addcslashes

(PHP 4 )

addcslashes -- Opatřit řetězec lomítky ve stylu jazyka C

Popis

string addcslashes ( string str, string charlist)

Vrací řetězec se zpětnými lomítky před znaky, které jsou vypsány v parametru charlist. Dále doplní \n, \r atd. podobně jako v jazyce C, znaky s ASCII kódem nižším než 32 a vyšším než 126 se převedou na osmičkovou reprezentaci.

Pokud zvolíte oescapovat znaky 0, a, b, f, n, r, t a v, budou konvertovány na \0, \a, \b, \f, \n, \r, \t a \v. V PHP \0 (NULL), \r (carriage return), \n (nový řádek) a \t (tab) jsou předdefinované escape sekvence, while in C all of these are predefined escape sequences.

V charlist můžete udat rozsah, např. "\0..\37", což by escapovalo všechny znaky s ASCII kódem mezi 0 a 31.

Příklad 1. Ukázka addcslashes()

$escaped = addcslashes ($not_escaped, "\0..\37!@\177..\377");

Pakliže uvádíte sekvenci znaků v parametru charlist ujistěte se, že víte které další znaky jdou mezi znaky, jež jsou uvedeny na začátku a na konci rozsahu.

echo addcslashes('foo[ ]', 'A..z');
// Výstup:  \f\o\o\[ \]
// Všechny velké i malé znaky budou escapovány
// ... but so will the [\]^_` and any tabs, line
// feeds, carriage returns, etc.

Také pokud první znak v rozsahu má nižší ASCII hodnotu než druhý znak v rozsahu, nebude žádný rozsah vytvořen. Pouze znkay začáteční, koncové a v periodě budou escapovány. Použijte funkci ord() k zjištění ASCII hodnoty znaků.

echo addcslashes("zoo['.']", 'z..A');
// Výstup:  \zoo['\.']

Viz také: stripcslashes(), stripslashes(), htmlspecialchars(), htmlspecialchars() a quotemeta().

addslashes

(PHP 3, PHP 4 )

addslashes -- Opatřit řetězec lomítky

Popis

string addslashes ( string str)

Vrací řetězec se zpětnými lomítky před znaky, které by ohly být problémové v databázových dotazech apod. Tyto znaky jsou jednoduchá uvozovka ('), dvojitá uvozovka ("), zpětné lomítko (\) a NUL (NULL byte).

Poznámka: magic_quotes_gpc výchozí hodnota je ON.

Viz také: stripslashes(), htmlspecialchars() a quotemeta().

bin2hex

(PHP 3>= 3.0.9, PHP 4 )

bin2hex -- Převést binární data na hexadecimální reprezentaci

Popis

string bin2hex ( string str)

Vrací ASCII řetězec obsahující hexadecimální reprezentaci str. Konverze probíhá po bytech, horní slabika první.

Dále také pack() a unpack().

chop

(PHP 3, PHP 4 )

chop -- Odstranit netisknutelné znaky z konce řetězce

Popis

string chop ( string str)

Vrací předaný řetězec bez netisknutelných znaků (vč. konců řádku) na konci.

Příklad 1. Ukázka chop()

$trimmed = chop ($line);

Poznámka: chop() se liší do Perlovské funkce chop(), která z řetězce odstraňuje poslední znak.

Viz také: trim(), ltrim(), rtrim() a chop().

chr

(PHP 3, PHP 4 )

chr -- Vrátit určitý znak

Popis

crypt() zašifruje řetězec pomocí standardní Unixovské šifrovací metody DES nebo alternativního algoritmu dostupného v operačním systému. Argumenty jsou řetězec k zašifrování a volitelný dvouznakový řetězec salt, na kterém se šifrování založí. Více informací naleznete v Unixovské man stránce vaší crypt funkce.

Není-li uveden salt, PHP jej náhodně vygeneruje.

Některé operační systémy podporují více typů šifrování. Někdy se standardní DES šifrování nahrazuje šifrovacím algoritmem založeným na MD5. Typ šifrování se zvolí podle argumentu salt. PHP zjistí pči instalaci schopnosti funkce crypt a bude přijímat salt pro další typy šifrování. Při absenci salt PHP automaticky vygeneruje standardní dvouznakový DES salt a v případě, že je výchozím typem šifrování na daném systému MD5, vygeneruje náhodný salt kompatibilní s MD5. PHP vytváří konstantu CRYPT_SALT_LENGTH, která vám řekne, jestli se na váš systém hodí běžný dvouznakový salt nebo delší dvanáctiznakový MD5 salt.

Používáte-li poskytnutý salt, měli byste si být vědomi toho, že se generuje jen jednou. Pokud tuto funkci voláte rekurzivně, může to mít účinek na vzhled a bezpečnost.

U standardního DES šifrování crypt() vrací salt jako první dva znaky výstupu. K tomu také používá jen prvních osum znaků z str, takže delší řetězce, ktewré začínají osmi stejnými znaky budou generovat i stejný výsledek (když je použit stejný salt).

Na systémech, kde funkce crypt()() podporuje více typů šifrování se následující konstanty nastaví na 0 nebo 1 podle toho, zda je daný typ dostupný:

CRYPT_STD_DES - Standardní DES šifrování s dvouznakovým SALT
CRYPT_EXT_DES - Rozšířené DES šifrování s devítiznakovým SALT
CRYPT_MD5 - MD5 šifrování s dvanáctiznakovým SALT začínajícím $1$
CRYPT_BLOWFISH - Rozšířené DES šifrování s šestnáctiznakovým SALT začínajícím $2$

Poznámka: Neexistuje žádná decrypt funkce, protože crypt() používá jednosměrný algoritmus.

Příklad 1. crypt() příklad

<?php
$heslo = crypt("MePrvniHeslo"); # necháme vygenerovat salt
# Mohli byste narazit na problémy při úplném výsledku crypt() jako salt pro
# porovnání hesla, pokud jsou použity rozdílné šifrovací algoritmy. (jak bylo
# řečeno výše, standardní DES šifrování používá dvouznakový salt, ale MD5
# šifrování používá dvanáctiznakový.
if (crypt($uziv_vstup, $heslo) == $heslo) {
   echo "Heslo ověřeno!";
}
?>

Dále také md5() a Mcrypt příkazy.

echo

(unknown)

echo -- Vytisknout jeden nebo více řetězců

Popis

echo ( string arg1 [, string argn...])

Vytiskne všechny parametry.

echo() vlastně není funkce (je to jazykový konstrukt), takže u něj nemusíte používat závorky. Opravdu, pokud byste potřebovali vytisknout více než jeden parametr, nemohli byste dokonce závorky vůbec použít. Proto nelze použít echo() ani pro proměnnou funkci, ovšem místo toho můžete použít funkci print().

Příklad 1. Ukázka echo()

<?php echo "Nazdar světe"; echo "Toto zabírá několik řádků. Konce řádků se vytisknou také"; echo "Toto zabírá\nněkolik řádků. Konce řádků se\nvytisknou také."; echo "Speciální znaky předřazené zpětnými lomítky lze použít i v řetězci \"jako toto\"."; //Proměnné lze použít i uvnitř příkazu echo $foo = "foobar"; $bar = "barbaz"; echo "foo je $foo"; // foo je foobar // Použitím jednoduchých uvozovek vypíšte jméno proměnné, nikoli její hodnotu echo 'foo je $foo'; // foo je $foo // Jestliže nepotřebujete vypisovat další znaky, můžete rovnou uvést jen názvy proměnných echo $foo; // foobar echo $foo, $bar; // foobarbarbaz echo <<<END Toto používá "dokumentovou" syntaxi pro víceřádkový výstup s vložnými $prommenymi. Uvědomte si, že ukončovací řetězec se středníkem musí být na začátku nového řádku (bez mezer či tabulátorů). END; // Protože echo není funkce, následující kód je neplatný ($some_var) ? echo('true'): echo('false'); // Nicméně tento příklad fungovat bude ($some_var) ? print('true'): print('false'); // print je funkce echo $some_var ? 'true': 'false'; // příkaz musíte uvést předtím ?>

echo() také má zkrácenou syntaxi, kdy je možné následně za otvíracím php tagem použít jen znak rovná se.

Mám <?=$foo?> foo.

Poznámka: Tato zkrácená syntaxe bude fungovat pouze jsou-li povoleny zkrácené otvírací php tagy; short_open_tag je nastaveno na "on".

Viz také: print(), printf() a flush().

explode

(PHP 3, PHP 4 )

explode -- Rozděluje řetězec jiným řetězcem

Popis

array explode ( string separator, string string [, int limit])

Vrací pole řetězců, z nichž každý je částí argumentu string vzniklý jeho rozdělením na hranicích tvořených řetězcem separator. Pokud je definován limit, vrácené pole bude obsahovat maximálně limit prvků, a poslední prvek bude obsahovat celý zbytek string.

Poznámka: Je-li separator prázdný řetězec (""), explode() vrátí FALSE. Pokud separator obsahuje hodnotu, která není obsažena v string, pak explode() vrátí pole obsahující celý string.

Argument limit byl přidán v PHP 4.0.1

Příklad 1. Ukázka explode()

$pizza = "piece1 piece2 piece3 piece4 piece5 piece6"; $pieces = explode (" ", $pizza); $data = "foo:*:1023:1000::/home/foo:/bin/sh"; list($user, $pass, $uid, $gid, $gecos, $home, $shell) = explode(":",$data);

Poznámka: I když implode() může z historických důvodů přijímat argumenty v obou možných pořadích, explode() nemůže. Musíte se ujistit, že je argument separator před argumentem string.

Viz také: preg_split(), spliti(), split() a implode().

get_html_translation_table

(PHP 4 )

get_html_translation_table -- Vrací překladovou tabulku používanou v htmlspecialchars() a htmlentities()

Popis

string get_html_translation_table ( int table [, int quote_style])

get_html_translation_table() vrací překladovou tabulku, která se interně používá ve funkcích htmlspecialchars() a htmlentities(). Dvě nové konstanty (HTML_ENTITIES, HTML_SPECIALCHARS) vám umožňují určit, kterou tabulku chcete. A stejně jako u funkcí htmlspecialchars() a htmlentities() můžete případně určit quote_style se kterým pracujete. Defaultní hodnota je ENT_COMPAT mód. Viz popis těchto módů u htmlspecialchars().

Příklad 1. Ukázka na překladovou tabulku

$trans = get_html_translation_table (HTML_ENTITIES); $str = "Hallo & <Frau> & Krämer"; $encoded = strtr ($str, $trans);
Proměnná $encoded teď obsahuje: "Hallo &amp; &lt;Frau&gt; &amp; Kr&auml;mer".

Skvělé je, že pomocí array_flip() můžete změnit směr překladu.

$trans = array_flip ($trans);
$original = strtr ($str, $trans);

Obsahem $original je: "Hallo & <Frau> & Krämer".

Poznámka: Tato funkce byla přidána v PHP 4.0.

Viz také: htmlspecialchars(), htmlentities(), strtr() a array_flip().

get_meta_tags

(PHP 3>= 3.0.4, PHP 4 )

get_meta_tags -- Získá hodnoty content atributů všech meta tagů v souboru a vrátí pole

Popis

array get_meta_tags ( string filename [, int use_include_path])

string htmlentities ( string string [, int quote_style [, string charset]])

Tato funkce je ve všem shodná s htmlspecialchars() kromě toho, že na HTML entity se převedou všechny znaky, které mají odpovídající entity. Stejně jako htmlspecialchars() přijímá volitelný druhý argument, který indikuje, co se má stát s jednoduchými a dvojitými uvozovkami. ENT_COMPAT (default) převede pouze dvojité uvozovky, ENT_QUOTES převede dvojité i jednoduché uvozovky, a ENT_NOQUOTES ponechá jednoduché i dvojité uvozovky bez konverze.

V současnosti se jako výchozí znaková sada používá ISO-8859-1. Volitelný druhý argument byl přidán v PHP 3.0.17 a PHP 4.0.3.

Stejně jako htmlspecialchars() lze pomocí třetího parametru nastavit znakovou sadu, která má být použita při konverzi řetězce. Tento třetí parametr byl přidán v PHP 4.1.0.

Neexistuje žádná zpětná funkce. Každopádně si můžete vytvořit vlastní. Následuje příklad jak na to.

Příklad 1. Zpětná htmlentities()

<?php
function unhtmlentities ($string)
{
	$trans_tbl = get_html_translation_table (HTML_ENTITIES);
	$trans_tbl = array_flip ($trans_tbl);
	return strtr ($string, $trans_tbl);
}
?>

Viz také: htmlspecialchars() a nl2br().

htmlspecialchars

(PHP 3, PHP 4 )

htmlspecialchars -- Převést zvláštní znaky na HTML entity

Popis

string htmlspecialchars ( string string [, int quote_style])

Některé znaky mají v HTML zvláštní význam, a pokud si mají zachovat běžný význam, měly by být reprezentovány HTML entitami. Tato funkce vrací řetězec, ve kterém došlo k některým z těchto konverzí; provádějí se ty překlady, které jsou v každodenním programování pro web nejužitečnější. Pokud požadujete překlad všech znakových entit HTML, použijte htmlentities().

Tato funkce je užitečná, pokud se chcete chránit před případným výskytem HTML v textu dodaném uživateli, například u aplikací typu kniha hostů nebo diskusní skupina. Volitelný druhý argument, quote_style, určuje, co se má stát s jednoduchými a dvojitými uvozovkami. Defaultní mód, ENT_COMPAT, je zpětně kompatibilní mód, konvertuje pouze dvojité uvozovky a jednoduché uvozovky ponechává nepřeložené. Pokud zadáte ENT_QUOTES, přeloží se jednoduché i dvojité uvozovky, a pokud zadáte ENT_NOQUOTES, oba druhy zůstanou bez překladu.

Dochází k těmto překladům:

'&' (ampersand) se stává '&'
'"' (dvojitá uvozovka) se stává '"' when ENT_NOQUOTES is not set.
''' (jednoduchá uvozovka) se stává ''' only when ENT_QUOTES is set.
'<' (menší než) se stává '<'
'>' (větší než) se stává '>'

Příklad 1. Ukázka htmlspecialchars()

$new = htmlspecialchars("<a href='test'>Test</a>", ENT_QUOTES);

Poznámka: tato funkce provádí pouze výše uvedené překlady. Kompletní překlad entit viz htmlentities(). Volitelný druhý argument byl přidán v PHP 3.0.17 a PHP 4.0.3.

Viz také: htmlentities() a nl2br().

implode

(PHP 3, PHP 4 )

implode -- Spojit prvky pole pomocí řetězce

Popis

string implode ( string glue, array pieces)

Vrací řetězec obsahující řetězcovou reprezentaci všech prvků pole v původním pořadí s řetězcem glue mezi každými dvěma prvky.

Příklad 1. Ukázka implode()

$colon_separated = implode (":", $array);

Poznámka: implode() může z historických důvodů přijímat argumenty v obou možných pořadích. Kvůli konzistenci s explode() se ale doporučuje používat dokumentované pořadí argumentů.

Viz také: explode(), join() a split().

join

(PHP 3, PHP 4 )

join -- Spojit prvky pole pomocí řetězce

Popis

string join ( string glue, array pieces)

Funkce join() je alias k implode(), a je ve všech ohledech stejná.

Viz také: explode(), implode() a split().

levenshtein

(PHP 3>= 3.0.17, PHP 4 >= 4.0.1)

levenshtein -- Spočítat XXX Levenshteinovu vzdálenost mezi dvěma řetězci

Popis

int levenshtein ( string str1, string str2)

int levenshtein ( string str1, string str2, int cost_ins, int cost_rep, int cost_del)

int levenshtein ( string str1, string str2, function cost)

Tato funkce vrací XXX Levenshtein-Distance mezi předanými řetězci nebo -1, pokud délka jednoho z předaných řetězců přesáhne omezení 255 znaků (255 by mělo být pro běžná porovnání víc než dost, a nikdo se zdravým rozumem nebude v PHP dělat genetickou analýzu).

Levenshteinova vzdálenost se definuje jako minimální počet znaku, které musíte nahradit, vložit nebo smazat, abyste změnili str1 na str2. Složitost tohoto algoritmu je O(m*n), kde n a m jsou délky str1 a str2 (celkem slušné v porovnání se similar_text(), který je O(max(n,m)**3), ale i tak drahé).

Ve své nejjednodušší podobě tato funkce pouze vezme dva řetězce jako argumenty a spočítá počet vložení, nahrazení a smazání nutných k transformaci str1 na str2.

Druhá varianta přijme tři další argumenty, které definují náklady na operace vložení, nahrazeni a smazání. Tato varianta je všeobecnější a přizpůsobivější než varianta první, ale ne tak výkonná.

Třetí varianta (zatím neimplementovaná) bude nejvšeobecnější a nejpřizpůsobivější, ale také nejpomalejší alternativou. Bude volat uživatelskou funkci, která určí náklady na všechny možné operace.

Tato uživatelská funkce se bude volat s následujícími argumenty:

operatce, která se má provést: 'I', 'R' or 'D'
původní znak v řetězci 1
původní znak v řetězci 2
pozice v řetězci 1
pozice v řetězci 2
znaky zbývající v řetězci 1
znaky zbývající v řetězci 2

Tato uživatelská funkce musí vrátit kladné celé číslo vyčíslující náklady na tuto konkrétní operaci, ale může se rozhodnout použít pouze některé z přijatých argumentů.

Tento přístup nabízí možnost zohlednit důležitost určitých symbolů (znaků) a/nebo rozdíly mezi nimi, či dokonce kontext, ve kterém se vyskytují při určování nákladů na vložení, změnu nebo smazání, ale za cenu ztráty všech optimalizací využití CPU registru a XXX cache misses, které byly zapracovány do předchozích dvou variant.

Viz také: soundex(), similar_text() a metaphone().

localeconv

(PHP 4 >= 4.0.5)

localeconv -- Get numeric formatting information

Description

array localeconv ( void)

Returns an associative array containing localized numeric and monetary formatting information.

localeconv() returns data based upon the current locale as set by setlocale(). The associative array that is returned contains the following fields:

Array element Description

decimal_point Decimal point character

thousands_sep Thousands separator

grouping Array containing numeric groupings

int_curr_symbol International currency symbol (i.e. USD)

currency_symbol Local currency symbol (i.e. $)

mon_decimal_point Monetary decimal point character

mon_thousands_sep Monetary thousands separator

mon_grouping Array containing monetary groupings

positive_sign Sign for positive values

negative_sign Sign for negative values

int_frac_digits International fractional digits

frac_digits Local fractional digits

p_cs_precedes TRUE if currency_symbol precedes a positive value, FALSE if it succeeds one

p_sep_by_space TRUE if a space separates currency_symbol from a positive value, FALSE otherwise

n_cs_precedes TRUE if currency_symbol precedes a negative value, FALSE if it succeeds one

n_sep_by_space TRUE if a space separates currency_symbol from a negative value, FALSE otherwise

p_sign_posn

0	Parentheses surround the quantity and currency_symbol
1	The sign string precedes the quantity and currency_symbol
2	The sign string succeeds the quantity and currency_symbol
3	The sign string immediately precedes the currency_symbol
4	The sign string immediately succeeds the currency_symbol

n_sign_posn

0	Parentheses surround the quantity and currency_symbol
1	The sign string precedes the quantity and currency_symbol
2	The sign string succeeds the quantity and currency_symbol
3	The sign string immediately precedes the currency_symbol
4	The sign string immediately succeeds the currency_symbol

The grouping fields contain arrays that define the way numbers should be grouped. For example, the grouping field for the en_US locale, would contain a 2 item array with the values 3 and 3. The higher the index in the array, the farther left the grouping is. If an array element is equal to CHAR_MAX, no further grouping is done. If an array element is equal to 0, the previous element should be used.

Příklad 1. localeconv() example

setlocale(LC_ALL, "en_US");

$locale_info = localeconv();

echo "<PRE>\n";
echo "--------------------------------------------\n";
echo "  Monetary information for current locale:  \n";
echo "--------------------------------------------\n\n";

echo "int_curr_symbol:   {$locale_info["int_curr_symbol"]}\n";
echo "currency_symbol:   {$locale_info["currency_symbol"]}\n";
echo "mon_decimal_point: {$locale_info["mon_decimal_point"]}\n";
echo "mon_thousands_sep: {$locale_info["mon_thousands_sep"]}\n";
echo "positive_sign:     {$locale_info["positive_sign"]}\n";
echo "negative_sign:     {$locale_info["negative_sign"]}\n";
echo "int_frac_digits:   {$locale_info["int_frac_digits"]}\n";
echo "frac_digits:       {$locale_info["frac_digits"]}\n";
echo "p_cs_precedes:     {$locale_info["p_cs_precedes"]}\n";
echo "p_sep_by_space:    {$locale_info["p_sep_by_space"]}\n";
echo "n_cs_precedes:     {$locale_info["n_cs_precedes"]}\n";
echo "n_sep_by_space:    {$locale_info["n_sep_by_space"]}\n";
echo "p_sign_posn:       {$locale_info["p_sign_posn"]}\n";
echo "n_sign_posn:       {$locale_info["n_sign_posn"]}\n";
echo "</PRE>\n";

The constant CHAR_MAX is also defined for the use mentioned above.

ltrim

(PHP 3, PHP 4 )

ltrim -- Odstranit netisknutelné znaky ze začátku řetězce

Popis

string ltrim ( string str)

Tato funkce ořízne netisknutelné znaky ze začátku řetězce a vrací oříznutý řetězec. Netisknutelné znaky, které se v současnosti odstraňují, jsou: "\n", "\r", "\t", "\v", "\0", a prostá mezera.

Viz také: chop(), rtrim() a trim().

md5_file

(PHP 4 >= 4.2.0)

md5_file -- Calculates the md5 hash of a given filename

Description

string md5_file ( string filename)

Calculates the MD5 hash of the specified filename using the RSA Data Security, Inc. MD5 Message-Digest Algorithm, and returns that hash.

This function has the same purpose of the command line utility md5sum.

md5

(PHP 3, PHP 4 )

md5 -- Spočítat MD5 XXX hash řetězce

Popis

string md5 ( string str)

Spočítá MD5 XXX hash argumentu str pomocí MD5 Message-Digest Algoritmu společnosti RSA Data Security, Inc..

Viz také: crc32().

metaphone

(PHP 4 )

metaphone -- Spočítat metaphone klíč řetězce

Popis

string metaphone ( string str)

Spočítá metaphone klíč argumentu str.

metaphone(), podobně jako soundex(), vytvoří stejný klíč pro podobně znějící slova. Je přesnější než soundex(), protože zná základní pravidla anglické výslovnosti. Metaphone klíče mají proměnlivou délku.

Metaphone vyvinul Lawrence Philips <lphilips@verity.com>. Je popsáno v ["Practical Algorithms for Programmers", Binstock & Rex, Addison Wesley, 1995].

Poznámka: Tato funkce byla přidána v PHP 4.0.

quoted_printable_decode

(PHP 3>= 3.0.6, PHP 4 )

quoted_printable_decode -- Převést quoted-printable řetězec na osmibitový řetězec

Popis

string quoted_printable_decode ( string str)

Tato funkce vrací osmibitový binární řetězec odpovídající dekódovanému quoted printable řetězci. Tato funkce je podobná imap_qprint() s tou výjimkou, že tato funkce nevyžaduje IMAP modul.

quotemeta

(PHP 3, PHP 4 )

quotemeta -- Opatřit lomítky metaznaky

Popis

string quotemeta ( string str)

Vrací verzi str se zpětným lomítkem před všemi výskyty následujících znaků:

. \\ + * ? [ ^ ] ( $ )

Viz také: addslashes(), htmlentities(), htmlspecialchars(), nl2br() a stripslashes().

rtrim

(PHP 3, PHP 4 )

rtrim -- Odstranit netisknutelné znaky z konce řetězce

Popis

string rtrim ( string str)

Vrací předaný řetězec bez netisknutelných znaků (vč. konců řádku) na konci. Toto je alias k chop().

Příklad 1. Ukázka rtrim()

$trimmed = rtrim ($line);

Viz také: trim(), ltrim() a rtrim().

setlocale

(PHP 3, PHP 4 )

setlocale -- Set locale information

Popis

string setlocale ( string category, string locale)

category je řetězec určující kategorii funkcí ovlivněných nastavením locale:

LC_ALL pro všechny níže uvedené kategorie
LC_COLLATE pro porovnávání řetězců - v PHP v současnosti neimplementováno
LC_CTYPE pro klasifikaci a konverzi znaků, např. strtoupper()
LC_MONETARY pro localeconv() - v PHP v současnosti neimplementováno
LC_NUMERIC pro oddělovač desetinných míst
LC_TIME pro formátování data a času pomocí strftime()

Pokud je locale prázný řetězec (""), názvy locale se nastaví na hodnoty systémových proměnných se stejnými jmény jako mají výše uvedené kategorie, nebo z "LANG".

Pokud je locale nula nebo "0", locale se nezmění, pouze se vrátí současná hodnota.

setlocale() vrací nové aktuální locale nebo FALSE, pokud na dotyčné platformě není funkcionalita locale implementována, zadané locale neexistuje, nebo je název kategorie neplatný. Neplatný název kategorie také vyvolá varování.

similar_text

(PHP 3>= 3.0.7, PHP 4 )

similar_text -- Spočítat podobnost dvou řetězců

Popis

int similar_text ( string first, string second [, double percent])

similar_text() spočítá podobnost dvou řetězců podle Oliver [1993]. Pozn.: Tato implementace nepoužívá stack jako v Oliverově pseudokódu, nýbrž rekurzivní volání, což může či nemusí celý proces zrychlit. Komplexita tohoto algoritmu je O(N**3) kde N je délka nejdelšího řetězce.

Pokud je similar_text() předán třetí argument (odkazem), spočítá tato funkce podobnost v procentech. Vrací počet znaků shodných v obou řetězcích.

soundex

(PHP 3, PHP 4 )

soundex -- Spočítat soundex klíč řetězce

Popis

string soundex ( string str)

Spočítá soundex klíč str.

Soundex klíče mají tu vlastnost, že slova vyslovovaná podobně produkují shodné soundex klíče, a dají se proto využít ke zjednodušení hledání v databázích, kde znáte výslovnost, ale ne hláskování. Tato funkce vrací řetězec dlouhý 4 znaky začínající písmenem.

Tato konkrétní soundex funkce je popsána Donaldem Knuthem v "The Art Of Computer Programming, vol. 3: Sorting And Searching", Addison-Wesley (1973), pp. 391-392.

Příklad 1. Soundex ukázky

soundex ("Euler") == soundex ("Ellery") == 'E460'; soundex ("Gauss") == soundex ("Ghosh") == 'G200'; soundex ("Hilbert") == soundex ("Heilbronn") == 'H416'; soundex ("Knuth") == soundex ("Kant") == 'K530'; soundex ("Lloyd") == soundex ("Ladd") == 'L300'; soundex ("Lukasiewicz") == soundex ("Lissajous") == 'L222';

sprintf

(PHP 3, PHP 4 )

sprintf -- Vrátit formátovaný řetězec

Popis

string sprintf ( string format [, mixed args])

Vrací řetězec vytvořený podle formátovacího řetězce format.

Formátovací řetězec se skládá z nula nebo více direktiv: běžných znaků (kromě %), které se přímo kopírují do výsledku, a převodních specifikací, z nichž každá přijímá jeden argument. Toto platí pro sprintf() i printf().

Každá převodní specifikace se skládá ze znaku procenta (%), následovaného jedním nebo více z těchto znaků, v tomto pořadí:

Volitelný padding specifier, který určuje, jaký znak se použije na doplnění výsledku na správnou délku řetězce. Může to být mezera nebo 0 (písmeno nula). Default je nula. Jiný doplňující znak můžete zadat tak, že před něj předřadíte jednoduchou uvozovku ('). Viz ukázky níže.
Volitelný alignment specifier, který určuje, jestli se má výsledek zarovnat doleva nebo doprava. Default je doprava, pomlčka (-) to změní na doleva.
Volitelné číslo width specifier, které určuje, kolik znaků (minimálně) má obsahovat výsledek převodu.
Volitelný precision specifier, který určuje, kolik desetinných míst se má zobrazit u čísel s desetinnou čárkou. Tento přepínač nemá žádný vliv na jiné typy než double. (Další funkcí užitečnou na formátování čísel je number_format().)

type specifier, který určuje, za jaký typ se mají data argumentu považovat. Možné typy:

% - a doslovný znak procenta. Nevyžaduje se žádný argument.

b - argument se považuje za integer a je prezentován jako binární číslo.

c - argument se považuje za integer a je prezentován jako znak s touto ASCII hodnotou.

d - argument se považuje za integer a je prezentován jako desítkové číslo.

f - argument se považuje za double a je prezentován jako číslo s plovoucí desetinou čárkou.

o - argument se považuje za integer a je prezentován jako oktalové číslo.

s - argument se považuje za řetězec a je takto prezentován.

x - the argument se považuje za integer a je prezentován jako hexadecimální číslo (s malými písmeny).

X - argument se považuje za integer a je prezentován jako hexadecimální číslo (s kapitálkami).

Viz také: printf(), sscanf(), fscanf() a number_format().

Ukázky

Příklad 1. Ukázka sprintf(): zero-padded integers

$isodate = sprintf ("%04d-%02d-%02d", $year, $month, $day);

Příklad 2. Ukázka sprintf(): formatting currency

$money1 = 68.75; $money2 = 54.35; $money = $money1 + $money2; // echo $money will output "123.1"; $formatted = sprintf ("%01.2f", $money); // echo $formatted will output "123.10"

sscanf

(PHP 4 >= 4.0.1)

sscanf -- Rozparsovat vstupní řetězec podle formátu

Popis

mixed sscanf ( string str, string format [, string var1])

Funkce sscanf() je vstupním analogem printf(). sscanf() čte řetězec str a interpretuje ho podle formátu format. Pokud jsou jí předány pouze dva argumenty, vrací rozparsované hodnoty v poli.

Příklad 1. Ukázka sscanf()

// zjištění sériového čísla $serial = sscanf("SN/2350001","SN/%d"); // a data výroby $mandate = "January 01 2000"; list($month, $day, $year) = sscanf($mandate,"%s %d %d"); echo "Zboží $serial bylo vyrobeno: $year-".substr($month,0,3)."-$day\n";
Pokud jsou jí předány volitelné argumenty, vrací tato funkce počet přiřazených hodnot. Volitelné argumenty musí být předány odkazem.

Příklad 2. Ukázka sscanf() - použití volitelných argumentů

// zjistit informace o autorovi a vygenerovat DocBook záznam $auth = "24\tLewis Carroll"; $n = sscanf($auth,"%d\t%s %s", &$id, &$first, &$last); echo "<author id='$id'> <firstname>$first</firstname> <surname>$last</surname> </author>\n";

Viz také: fscanf(), printf() a sprintf().

str_pad

(PHP 4 >= 4.0.1)

str_pad -- Doplnit řetězec jiným řetězcem na určitou délku

Popis

string str_pad ( string input, int pad_length [, string pad_string [, int pad_type]])

str_pad() doplní řetězec input zleva, zprava nebo z obou stran na danou délku. Pokud jí není předán volitelný argument pad_string, doplní se input mezerami, jinak se doplní znaky z pad_string.

Volitelný argument pad_type může nabýt hodnot STR_PAD_RIGHT, STR_PAD_LEFT nebo STR_PAD_BOTH. Default je STR_PAD_RIGHT.

Pokud je hodnota pad_length negativní nebo menší než je délka input, k doplnění nedojde.

Příklad 1. Ukázka str_pad()

$input = "Alien"; print str_pad($input, 10); // produces "Alien " print str_pad($input, 10, "-=", STR_PAD_LEFT); // produces "-=-=-Alien" print str_pad($input, 10, "_", STR_PAD_BOTH); // produces "__Alien___"

str_repeat

(PHP 4 )

str_repeat -- Opakovat řetězec

Popis

string str_repeat ( string input, int multiplier)

Vrací input_str multiplier krát opakovaný. multiplier musí být větší než 0.

Příklad 1. Ukázka str_repeat()

echo str_repeat ("-=", 10);

This will output "-=-=-=-=-=-=-=-=-=-=".

Poznámka: Tato funkce byla přidána v PHP 4.0.

str_replace

(PHP 3>= 3.0.6, PHP 4 )

str_replace -- Nahradit všechny výskyty jednoho řetězce v jiném dalším řetězcem

Popis

string str_replace ( string needle, string str, string haystack)

Tato funkce nahradí všechny výskyty needle v argumentu haystack argumentem str. Pokud nepotřebujete složitá pravidla pro nahrazování, měli byste vždy použít tuto funkci místo ereg_replace().

Příklad 1. Ukázka str_replace()

$bodytag = str_replace ("%body%", "black", "<body text=%body%>");

Tato funkce je XXX binárně bezpečná.

Poznámka: Funkce str_replace() byla přidána v PHP 3.0.6, ale až do verze PHP 3.0.8 fungovala špatně.

Viz také: ereg_replace() a strtr().

str_rot13

(PHP 4 >= 4.2.0)

str_rot13 -- Perform the rot13 transform on a string

Description

string str_rot13 ( string str)

This function performs the ROT13 encoding on the str argument and returns the resulting string. The ROT13 encoding simply shifts every letter by 13 places in the alphabet while leaving non-alpha characters untouched. Encoding and decoding are done by the same function, passing an encoded string as argument will return the original version.

strcasecmp

(PHP 3>= 3.0.2, PHP 4 )

strcasecmp -- Binárně bezpečné case-insensitive porovnání řetězců

Popis

int strcasecmp ( string str1, string str2)

Pokud je str1 méně než str2 vrací < 0; pokud je str1 větší než str2 vrací > 0, a 0, pokud jsou stejné.

Příklad 1. Ukázka strcasecmp()

$var1 = "Hello"; $var2 = "hello"; if (!strcasecmp ($var1, $var2)) { echo 'v case-insensitive textovém porovnání se $var1 rovná $var2'; }

Viz také: ereg(), strcmp(), substr(), stristr(), strncasecmp() a strstr().

strchr

(PHP 3, PHP 4 )

strchr -- Najít první výskyt znaku

Popis

string strchr ( string haystack, string needle)

Tato funkce je alias k strstr(), a je ve všech směrech identická.

strcmp

(PHP 3, PHP 4 )

strcmp -- Binárně bezpečně porovnat řetězce

Popis

int strcmp ( string str1, string str2)

Pokud je str1 méně než str2, vrací < 0; pokud je str1 větší než str2, vrací > 0, a 0, pokud jsou stejné.

Pozn.: toto srovnání je case-sensitive.

Viz také: ereg(), strcasecmp(), substr(), stristr(), strncasecmp(), strncmp() a strstr().

strcoll

(PHP 4 >= 4.0.5)

strcoll -- Locale based string comparison

Description

int strcoll ( string str1, string str2)

Returns < 0 if str1 is less than str2; > 0 if str1 is greater than str2, and 0 if they are equal. strcoll() uses the current locale for doing the comparisons. If the current locale is C or POSIX, this function is equivalent to strcmp().

Note that this comparison is case sensitive, and unlike strcmp() this function is not binary safe.

strcspn

(PHP 3>= 3.0.3, PHP 4 )

strcspn -- Najít délku úvodního segmentu neodpovídajícího masce

Popis

Vrací řetězec bez odstraněných zpětných lomítek. (\' se stává ' a pod.) Zdvojená zpětná lomítka se spojují do jednoduchých.

Viz také: addslashes().

stristr

(PHP 3>= 3.0.6, PHP 4 )

stristr -- Case-insensitive strstr()

Popis

string stristr ( string haystack, string needle)

Vrací haystack od prvního výskytu needle do konce. needle a haystack se zkoumají bez ohledu na velikost písmen.

Pokud needle nenajde, vrací FALSE.

Pokud needle není řetězec, převede se na integer a použije se jako XXX ordinal hodnota znaku.

Viz také: strchr(), strrchr(), substr() a ereg().

strlen

(PHP 3, PHP 4 )

strlen -- Zjistit délku řetězce

Popis

int strlen ( string str)

Vrací délku (počet znaků) argumentu string.

strnatcasecmp

(PHP 4 )

strnatcasecmp -- Case-insensitive textové porovnání s využitím "natural order" algoritmu

Popis

int strnatcasecmp ( string str1, string str2)

Tato funkce implementuje srovnávací algoritmus který třídí alfanumerické řetězce stejným způsobem jako člověk. Chování této funkce se podobá strnatcmp() s tou výjimkou, že porovnání je case-insensitive. Více informací viz stránka Martina Poola Natural Order String Comparison.

Podobně jako jiné funkce pro porovnávání řetězců i tato vrací < 0 pokud je str1 menší než str2; > 0 pokud je str1 větší než str2, a 0 pokud jsou shodné.

Viz také: ereg(), strcasecmp(), substr(), stristr(), strcmp(), strncmp(), strncasecmp(), strnatcmp() a strstr().

strnatcmp

(PHP 4 )

strnatcmp -- Porovnání řetězců algoritmem "přirozeného třídění"

Popis

int strnatcmp ( string str1, string str2)

$arr1 = $arr2 = array ("img12.png","img10.png","img2.png","img1.png");
echo "Standardní porovnávání řetězců\n";
usort($arr1,"strcmp");
print_r($arr1);
echo "\nPřirozené porovnávání řetězců\n";
usort($arr2,"strnatcmp");
print_r($arr2);

Výše uvedený kód vygeneruje následující výstup:

Standardní porovnávání řetězců
Array
(
    [0] => img1.png
    [1] => img10.png
    [2] => img12.png
    [3] => img2.png
)

Přirozené porovnávání řetězců
Array
(
    [0] => img1.png
    [1] => img2.png
    [2] => img10.png
    [3] => img12.png
)

Více informací viz stránka Martina Poola Natural Order String Comparison.

Podobně jako jiné funkce pro porovnávání řetězců i tato vrací < 0 pokud je str1 menší než str2; > 0 pokud je str1 větší než str2, a 0 pokud jsou shodné.

Pozn.: toto porovnání je case-sensitive.

Viz také: ereg(), strcasecmp(), substr(), stristr(), strcmp(), strncmp(), strncasecmp(), strnatcasecmp(), strstr(), natsort() a natcasesort().

strncasecmp

(PHP 4 >= 4.0.2)

strncasecmp -- Binárně bezpečné case-insensitive porovnání prvních n znaků řetězců

Popis

int strncasecmp ( string str1, string str2, int len)

Tato funkce se podobá strcasecmp(), s tím rozdílem, že můžete určit (maximální) počet znaků (len) z každého z řetězců, které se použijí při porovnání. Pokud je některý z řetězců kratší než len, pak se pro porovnání použije délka tohoto řetězce.

Pokud je str1 méně než str2, vrací < 0; pokud je str1 větší než str2, vrací > 0, a 0, pokud jsou stejné.

Viz také: ereg(), strcasecmp(), strcmp(), substr(), stristr() a strstr().

strncmp

(PHP 4 )

strncmp -- Binárně bezpečné porovnání prvních n znaků v řetězcích

Popis

int strncmp ( string str1, string str2, int len)

This function is similar to strcmp(), with the difference that you can specify the (upper limit of the) number of characters (len) from each string to be used in the comparison. If any of the strings is shorter than len, then the length of that string will be used for the comparison.

Vrací < 0 pokud je str1 menší než str2; > 0 pokud je str1 větší než str2, a 0 pokud jsou shodné.

Pozn.: toto srovnání je case-sensitive.

Viz také: ereg(), strncasecmp(), strcasecmp(), substr(), stristr(), strcmp() a strstr().

strpos

(PHP 3, PHP 4 )

strpos -- Najít pozici prvního výskytu řetězce

Popis

int strpos ( string haystack, string needle [, int offset])

Vrací číselnou pozici prvního výskytu needle v řetězci haystack. Narozdíl od strrpos() tato funkce přijme jako argument needle řetězec více znaků, a celý tento řetězec se použije.

Pokud needle nenajde, vrací FALSE.

Poznámka: Návratové hodnoty "znak nalezen na pozici 0" a "znak nenalezen" se dají snadno zaměnit. Tady je návod, jak zjistit tento rozdíl:
// v PHP 4.0b3 a novějších:
$pos = strpos ($mystring, "b");
if ($pos === false) { // tři rovnítka
    // nenalezeno...
}

// ve verzích starších než 4.0b3:
$pos = strpos ($mystring, "b");
if (is_string ($pos) && !$pos) {
    // nenalezeno...
}

Pokud needle není řetězec, převede se na integer a použije se jako XXX ordinal hodnota znaku.

Volitelný argument offset vám umožňuje určit na které pozici v haystack má hledání začít. Vrácená pozice je i tak relativní k začátku haystack.

Viz také: strrpos(), strrchr(), substr(), stristr() a strstr().

strrchr

(PHP 3, PHP 4 )

strrchr -- Najít poslední výskyt znaku v řetězci

Popis

string strrchr ( string haystack, string needle)

Tato funkce vrací tu část haystack, která začíná poslením výskytem needle a pokračuje do konce haystack.

Pokud needle nenajde, vrací FALSE.

Pokud needle obsahuje více než jeden znak, použije se první z nich.

Pokud needle není řetězec, převede se na integer a použije se jako XXX ordinal hodnota znaku.

Příklad 1. Ukázka strrchr()

// získat poslední adresář v $PATH $dir = substr (strrchr ($PATH, ":"), 1); // získat všechno po posledním konci řádku $text = "Řádek 1\nŘádek 2\nŘádek 3"; $last = substr (strrchr ($text, 10), 1 );

Viz také: substr(), stristr() a strstr().

strrev

(PHP 3, PHP 4 )

strrev -- Obrátit řetězec

Popis

string strrev ( string string)

Vrací string v opačném pořadí.

strrpos

(PHP 3, PHP 4 )

strrpos -- Najít pozici posledního výskytu znaku v řetězci

Popis

int strrpos ( string haystack, char needle)

Vrací číselnou pozici posledního výskytu needle v řetězci haystack. needle může být jen jeden znak dlouhá. Pokud obsahuje více znaků, použije se první z nich.

Pokud needle nenajde, vrací FALSE.

Poznámka: Návratové hodnoty "znak nalezen na pozici 0" a "znak nenalezen" se dají snadno zaměnit. Tady je návod, jak zjistit tento rozdíl:
// v PHP 4.0b3 a novějších:
$pos = strpos ($mystring, "b");
if ($pos === false) { // tři rovnítka
    // nenalezeno...
}

// ve verzích starších než 4.0b3:
$pos = strpos ($mystring, "b");
if (is_string ($pos) && !$pos) {
    // nenalezeno...
}

Pokud needle není řetězec, převede se na integer a použije se jako XXX ordinal hodnota znaku.

Viz také: strpos(), strrchr(), substr(), stristr() a strstr().

strspn

(PHP 3>= 3.0.3, PHP 4 )

strspn -- Zjistit délku úvodního segmentu odpovídajícího masce

Popis

int strspn ( string str1, string str2)

Vrací úvodního segmentu str1, který se skládá výhradně ze znaků v str2.

strspn ("42 je odpověď, co je otázka...", "1234567890");

vrátí 2.

Viz také: strcspn().

strstr

(PHP 3, PHP 4 )

strstr -- Najít první výskyt řetězce

Popis

string strstr ( string haystack, string needle)

Vrací část haystack od prvního výskytu needle do konce.

Pokud needle nenajde, vrací FALSE.

Pokud needle není řetězec, převede se na integer a použije se jako XXX ordinal hodnota znaku.

Poznámka: Pozn.: tato funkce je case-sensitive. Pro case-insensitive hledání použijte stristr().

Příklad 1. Ukázka strstr()

$email = 'sterling@designmultimedia.com'; $domain = strstr ($email, '@'); print $domain; // vytiskne @designmultimedia.com

Viz také: stristr(), strrchr(), substr() a ereg().

strtok

(PHP 3, PHP 4 )

strtok -- Tokenize string

Popis

Tato funkce upraví str tak, že všechny výskyty všech znaků ve from přeloží na odpovídající znaky v to a vrátí výsledek.

Pokud jsou from a to různě dlouhé, přebývající znaky z delšího z těch dvou se ignorují.

Příklad 1. Ukázka strtr()

$addr = strtr($addr, "äĺö", "aao");

strtr() se dá také volat pouze se dvěma argumenty. Při volání se dvěma argumenty se chová takto: from musí být pole obsahující páry řetězců, které se zamění ve zdrojovém řetězci. strtr() vždy hledá nejdelší možnou shodu a *NENAHRAZUJE* ty části řetězce, na kterých už pracovala.

Ukázky:

$trans = array ("ahoj" => "nazdar", "nazdar" => "ahoj");
echo strtr("nazdar lidi, řekl jsem ahoj", $trans) . "\n";

Výsledek: "ahoj lidi, řekl jsem nazdar",

Poznámka: Tato vlastnost (dva argumenty) byla přidána v PHP 4.0.

Viz také: ereg_replace().

substr_count

(PHP 4 )

substr_count -- Spočítat počet výskytů řetězce

Popis

int substr_count ( string haystrack, string needle)

substr_count() vrací počet výskytů řetězce needle v řetězci haystack string.

Příklad 1. Ukázka substr_count()

print substr_count("This is a test", "is"); // prints out 2

substr_replace

(PHP 4 )

substr_replace -- Nahradit část řetězce jiným řetězcem

Popis

string substr_replace ( string string, string replacement, int start [, int length])

substr_replace() nahrazuje část řetězce string ohraničenou argumenty start a (volitelně) length řetězcem v argumentu replacement. Vrací výsledek.

Pokud je start pozitivní, náhrada začne na start-tém znaku argumentu string.

Pokud je start negativní, náhrada začne na start-tém znaku od konce argumentu string.

Pokud je přítomen length, a je pozitivní, představuje délku části argumentu string, která bude nahražena. Pokud je negativní, představuje počet znaků od konce string, kde má nahrazování skončit. Pokud přítomen není, bere se standardně strlen( string ); tj. nahrazování končí na konci argumentu string.

Příklad 1. Ukázka substr_replace()

<?php $var = 'ABCDEFGH:/MNRPQR/'; echo "Originál: $var<hr>\n"; /* Tyto dva příklady nahradí celý obsah proměnné $var řetězcem 'bob'. */ echo substr_replace ($var, 'bob', 0) . "<br>\n"; echo substr_replace ($var, 'bob', 0, strlen ($var)) . "<br>\n"; /* Toto vloží 'bob' na začátek $var. */ echo substr_replace ($var, 'bob', 0, 0) . "<br>\n"; /* Tyto dva příklady nahradí 'MNRPQR' ve $var řetězcem 'bob'. */ echo substr_replace ($var, 'bob', 10, -1) . "<br>\n"; echo substr_replace ($var, 'bob', -7, -1) . "<br>\n"; /* Toto z $var odstraní 'MNRPQR'. */ echo substr_replace ($var, '', 10, -1) . "<br>\n"; ?>

Viz také str_replace() a substr().

Poznámka: Funkce substr_replace() byla přidána v PHP 4.0.

substr

(PHP 3, PHP 4 )

substr -- Vrátit část řetězce

Popis

string substr ( string string, int start [, int length])

substr() vrací část argumentu string určenou argumenty start a length.

Pokud je start pozitivní, vrácený řetězec začne start-tým znakem řetězce string, počítáno od nuly. Například v řetězci 'abcdef' je znakem na 0-té pozici 'a', znakem na pozici 2 je 'c', atd.

Příklady:

$rest = substr ("abcdef", 1);    // vrátí "bcdef"
$rest = substr ("abcdef", 1, 3); // vrátí "bcd"

Pokud je start negativní, vrácený řetězec začne start-tým znakem od konce argumentu string.

Příklady:

$rest = substr ("abcdef", -1);    // vrátí "f"
$rest = substr ("abcdef", -2);    // vrátí "ef"
$rest = substr ("abcdef", -3, 1); // vrátí "d"

Pokud je argument length kladný, vrácený řetězec skončí length znaků od start. Pokud by to znamenalo řetězec se zápornou délkou (start je za length), vrácený řetězec bude sestávat z jediného znaku na pozici start.

Pokud je argument length kladný, vrácený řetězec skončí length znaků od konce argumentu string. Pokud by to znamenalo řetězec se zápornou délkou, vrácený řetězec bude sestávat z jediného znaku na pozici start.

Příklady:

$rest = substr ("abcdef", 1, -1); // vrátí "bcde"

Viz také: strrchr() a ereg().

trim

(PHP 3, PHP 4 )

trim -- Odstranit netisknutelné znaky ze začátku a konce řetězce

Popis

string trim ( string str)

Tato funkce odstraňuje netisknutelné znaky ze začátku a konce řetězce a vrací řetězec bez těchto znaků. Netisknutelné znaky, které se v současnosti odstraňují, jsou: "\n", "\r", "\t", "\v", "\0", a mezera.

Viz také chop(), rtrim() a ltrim().

ucfirst

(PHP 3, PHP 4 )

ucfirst -- Změní první písmeno řetězce na velké

Popis

string ucfirst ( string str)

Změní první znak argumentu str, pokud je tento znak alfabetický.

Pozn.: co znamená 'alfabetický' určuje aktuální místní nastavení (locale). Například ve standardním "C" locale se znaky jako přehlasované a (ä) nepřevedou.

Příklad 1. Ukázka ucfirst()

$text = 'mary had a little lamb and she loved it so.'; $text = ucfirst ($text); // $text is now Mary had a little lamb // and she loved it so.

Viz také strtoupper() a strtolower().

ucwords

(PHP 3>= 3.0.3, PHP 4 )

ucwords -- Změnit první znak každého slova v řetězci na velké písmeno

Popis

string ucwords ( string str)

Změní první znak každého slova v argumentu str na velké písmeno, pokud je tento znak alfabetický.

Příklad 1. Ukázka ucwords()

$text = "mary had a little lamb and she loved it so."; $text = ucwords($text); // $text is now: Mary Had A Little // Lamb And She Loved It So.

Poznámka: Definice slova je: jakýkoli řetězec znaků, který následuje bezprostředně po netisknutelném znaku (to jsou: mezera, posun o tiskouvou stranu, přesun na novou řádku, návrat vozíku, horizontální tabelátor a vertikální tabelátor0.

Viz také strtoupper(), strtolower() and ucfirst().

vprintf

(PHP 4 >= 4.1.0)

vprintf -- Output a formatted string

Description

void vprintf ( string format, array args)

Display array values as a formatted string according to format (which is described in the documentation for sprintf()).

Operates as printf() but accepts an array of arguments, rather than a variable number of arguments.

vsprintf

(PHP 4 >= 4.1.0)

vsprintf -- Return a formatted string

Description

string vsprintf ( string format, array args)

Return array values as a formatted string according to format (which is described in the documentation for sprintf()).

Operates as sprintf() but accepts an array of arguments, rather than a variable number of arguments.

See also: sprintf(), vsprintf(), vprintf()

wordwrap

(PHP 4 >= 4.0.2)

wordwrap -- Zalámat řetězec na daný počet znaků pomocí break znaku

Popis

string wordwrap ( string str [, int width [, string break [, int cut]]])

Zaláme řetězec str na sloupci určeném (volitelným) argumentem break.

Pokud není zadán argument width nebo break, wordwrap() automaticky zaláme řádky řetězce na sloupci 75 znakem '\n' (konec řádku).

Pokud má argument cut hodnotu 1, řetězec se na určenou šířku zalomí vždy. Takže pokud máte slovo delší než je daná šířka, rozdělí se. (Viz druhý příklad.)

Poznámka: Argument cut byl přidán PHP 4.0.3.

Příklad 1. Ukázka wordwrap()

$text = "Rychlá hnědá liška přeskočila líného psa."; $newtext = wordwrap( $text, 20 ); echo "$newtext\n";

Tato ukázka by zobrazila:

Rychlá hnědá liška
přeskočila líného psa.

Příklad 2. Ukázka wordwrap()

$text = "Velmi dlouhé slooooooooooovo."; $newtext = wordwrap( $text, 8, "\n", 1); echo "$newtext\n";

Tato ukázka by zobrazila:

Velmi
dlouhé
sloooooo
ooooovo.

Viz také: nl2br().

XCVIII. Sybase functions

Obsah
sybase_affected_rows -- get number of affected rows in last query
sybase_close -- close Sybase connection
sybase_connect -- open Sybase server connection
sybase_data_seek -- move internal row pointer
sybase_fetch_array -- fetch row as array
sybase_fetch_field -- get field information
sybase_fetch_object -- fetch row as object
sybase_fetch_row -- get row as enumerated array
sybase_field_seek -- set field offset
sybase_free_result -- free result memory
sybase_get_last_message -- Returns the last message from the server
sybase_min_client_severity -- Sets minimum client severity
sybase_min_error_severity -- Sets minimum error severity
sybase_min_message_severity -- Sets minimum message severity
sybase_min_server_severity -- Sets minimum server severity
sybase_num_fields -- get number of fields in result
sybase_num_rows -- get number of rows in result
sybase_pconnect -- open persistent Sybase connection
sybase_query -- send Sybase query
sybase_result -- get result data
sybase_select_db -- select Sybase database

sybase_affected_rows

(PHP 3>= 3.0.6, PHP 4 )

sybase_affected_rows -- get number of affected rows in last query

Description

int sybase_affected_rows ( [int link_identifier])

Returns: The number of affected rows by the last query.

sybase_affected_rows() returns the number of rows affected by the last INSERT, UPDATE or DELETE query on the server associated with the specified link identifier. If the link identifier isn't specified, the last opened link is assumed.

This command is not effective for SELECT statements, only on statements which modify records. To retrieve the number of rows returned from a SELECT, use sybase_num_rows().

Poznámka: This function is only available using the CT library interface to Sybase, and not the DB library.

sybase_fetch_array -- fetch row as array

Description

array sybase_fetch_array ( int result)

Returns: An array that corresponds to the fetched row, or FALSE if there are no more rows.

sybase_fetch_array() is an extended version of sybase_fetch_row(). In addition to storing the data in the numeric indices of the result array, it also stores the data in associative indices, using the field names as keys.

An important thing to note is that using sybase_fetch_array() is NOT significantly slower than using sybase_fetch_row(), while it provides a significant added value.

For further details, also see sybase_fetch_row().

sybase_fetch_field

(PHP 3, PHP 4 )

sybase_fetch_field -- get field information

Description

object sybase_fetch_field ( int result [, int field_offset])

Returns an object containing field information.

sybase_fetch_field() can be used in order to obtain information about fields in a certain query result. If the field offset isn't specified, the next field that wasn't yet retreived by sybase_fetch_field() is retreived.

The properties of the object are:

name - column name. if the column is a result of a function, this property is set to computed#N, where #N is a serial number.
column_source - the table from which the column was taken
max_length - maximum length of the column
numeric - 1 if the column is numeric
type - datatype of the column

sybase_fetch_object

(PHP 3, PHP 4 )

sybase_fetch_object -- fetch row as object

Description

int sybase_fetch_object ( int result)

Returns: An object with properties that correspond to the fetched row, or FALSE if there are no more rows.

Poznámka: This function is only available using the CT library interface to Sybase, and not the DB library.

Second, the connection to the SQL server will not be closed when the execution of the script ends. Instead, the link will remain open for future use (sybase_close() will not close links established by sybase_pconnect()()).

This type of links is therefore called 'persistent'.

sybase_query

(PHP 3, PHP 4 )

sybase_query -- send Sybase query

Description

int sybase_query ( string query, int link_identifier)

Returns: A positive Sybase result identifier on success, or FALSE on error.

sybase_query() sends a query to the currently active database on the server that's associated with the specified link identifier. If the link identifier isn't specified, the last opened link is assumed. If no link is open, the function tries to establish a link as if sybase_connect() was called, and use it.

See also: sybase_db_query(), sybase_select_db(), and sybase_connect().

sybase_result

(PHP 3, PHP 4 )

sybase_result -- get result data

Description

string sybase_result ( int result, int row, mixed field)

Returns: The contents of the cell at the row and offset in the specified Sybase result set.

sybase_result() returns the contents of one cell from a Sybase result set. The field argument can be the field's offset, or the field's name, or the field's table dot field's name (tablename.fieldname). If the column name has been aliased ('select foo as bar from...'), use the alias instead of the column name.

When working on large result sets, you should consider using one of the functions that fetch an entire row (specified below). As these functions return the contents of multiple cells in one function call, they're MUCH quicker than sybase_result(). Also, note that specifying a numeric offset for the field argument is much quicker than specifying a fieldname or tablename.fieldname argument.

Recommended high-performance alternatives: sybase_fetch_row(), sybase_fetch_array(), and sybase_fetch_object().

sybase_select_db

(PHP 3, PHP 4 )

sybase_select_db -- select Sybase database

Description

bool sybase_select_db ( string database_name, int link_identifier)

Returns: TRUE on success, FALSE on error

sybase_select_db() sets the current active database on the server that's associated with the specified link identifier. If no link identifier is specified, the last opened link is assumed. If no link is open, the function will try to establish a link as if sybase_connect() was called, and use it.

Every subsequent call to sybase_query() will be made on the active database.

XCIX. Tokenizer functions

Varování

Obsah
token_get_all -- Split given source in tokens
token_name -- Get the name of a given token

token_get_all

(PHP 4 >= 4.2.0)

token_get_all -- Split given source in tokens

Description

array token_get_all ( string source)

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

token_name

(PHP 4 >= 4.2.0)

token_name -- Get the name of a given token

Description

string token_name ( int type)

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

C. URL Functions

Obsah
base64_decode -- Dekódovat data kódovaná pomocí MIME base64
base64_encode -- Zakódovat data pomocí MIME base64
parse_url -- Rozebrat URL a vrátit její komponenty
rawurldecode -- Dekódovat URL-kódovaný řetězec
rawurlencode -- URL-kódovat podle RFC1738
urldecode -- Dekódovat URL-kódovaný řetězec
urlencode -- URL-kódovat řetězec

base64_decode

(PHP 3, PHP 4 )

base64_decode -- Dekódovat data kódovaná pomocí MIME base64

Popis

string base64_decode ( string encoded_data)

base64_decode() dekóduje encoded_data a vrátí původní data. Vrácená data mohou být binární

Viz také: base64_encode(), RFC 2045 sekce 6.8.

base64_encode

(PHP 3, PHP 4 )

base64_encode -- Zakódovat data pomocí MIME base64

Popis

string base64_encode ( string data)

base64_encode() vrátí data zakódovaný pomocí base64. Toto kódování je navrženo tak, aby umožnilo binárním datům přežít transport přenosovými vrstvami, které nejsou osmibitové, jako jsou například těla emailů.

Data kódovaná pomocí base64 zabírají o zhruba 33% prostoru více než původní data.

Viz také: base64_decode(), chunk_split(), RFC-2045 sekce 6.8.

parse_url

(PHP 3, PHP 4 )

parse_url -- Rozebrat URL a vrátit její komponenty

string urlencode ( string str)

Vrátí řetězec, ve kterém byly všechny nealfanumerické znaky kromě -_. nahrazeny znakem procent (%) následovaným dvěma šestnácktovými číslicemi a mezery kódovány jako znaky plus (+). Kódování je stejné jako u dat postovaných z WWW formuláře, tj. stejně jako u application/x-www-form-urlencoded typu. To se liší od RFC1738 kódování (viz rawurlencode()) v tom, že z historických důvodů se mezery kódují jako znaky plus (+). Tato funkce je vhodná při kódování řetězce, který se má použít jako query část URL jako příhodný způsob předání proměnných na další stránku:

Příklad 1. Příklad urlencode()

echo '<A HREF="mycgi?foo=', urlencode ($userinput), '">';

Poznámka: pozor při předávání proměnných, které by mohly odpovídat HTML entitám. Věci jako &amp, &copy a &pound browser analyzuje a místo požadovaného jména proměnné použije odpovídající entitu. To je zřejmý problém, na který W3C upozorňuje už léta. Příručka je tady: http://www.w3.org/TR/html4/appendix/notes.html#h-B.2.2 PHP podporuje změnu oddělovače argumentů na středník doporučovaný W3C skrze .ini direktivu arg_separator. Bohužel, většina uživatelských programů neposílá data z formulářů v tomto formátu. Přenositelnější formou je použít jako oddělovač & místo &. Na to nemusíte měnit arg_separator. Nechte ho na &, ale kódujte URL pomocí htmlentities() (urlencode($data)).

Příklad 2. Příklad na urlencode/htmlentities()

echo '<A HREF="mycgi?foo=', htmlentities (urlencode ($userinput) ), '">';

Viz také urldecode(), htmlentities(), rawurldecode(), rawurlencode().

CI. Variable Functions

For information on how variables behave, see the Variables entry in the Language Reference section of the manual.

Obsah
doubleval -- Alias of floatval()
empty -- Determine whether a variable is set
floatval -- Get float value of a variable
get_defined_vars -- Returns an array of all defined variables
get_resource_type -- Returns the resource type
gettype -- Get the type of a variable
import_request_variables -- Import GET/POST/Cookie variables into the global scope
intval -- Get integer value of a variable
is_array -- Finds whether a variable is an array
is_bool -- Finds out whether a variable is a boolean
is_callable -- Find out whether the argument is a valid callable construct
is_double -- Alias of is_float()
is_float -- Finds whether a variable is a float
is_int -- Find whether a variable is an integer
is_integer -- Alias of is_int()
is_long -- Alias of is_int()
is_null -- Finds whether a variable is NULL
is_numeric -- Finds whether a variable is a number or a numeric string
is_object -- Finds whether a variable is an object
is_real -- Alias of is_float()
is_resource -- Finds whether a variable is a resource
is_scalar -- Finds whether a variable is a scalar
is_string -- Finds whether a variable is a string
isset -- Determine whether a variable is set
print_r -- Prints human-readable information about a variable
serialize -- Generates a storable representation of a value
settype -- Set the type of a variable
strval -- Get string value of a variable
unserialize -- Creates a PHP value from a stored representation
unset -- Unset a given variable
var_dump -- Dumps information about a variable
var_export -- Outputs or returns a string representation of a variable

doubleval

(PHP 3, PHP 4 )

doubleval -- Alias of floatval()

Description

This function is an alias of floatval().

Poznámka: This alias is a left-over from a function-renaming. In older versions of PHP you'll need to use this alias of the floatval() function, because floatval() wasn't yet available in that version.

empty

(unknown)

empty -- Determine whether a variable is set

Description

boolean empty ( mixed var)

Poznámka: empty() is a language construct.

This is the opposite of (boolean) var, except that no warning is generated when the variable is not set. See converting to boolean for more information.

$var = 0;

if (empty($var)) {  // evaluates true
    echo '$var is either 0 or not set at all';
}

if (!isset($var)) { // evaluates false
    echo '$var is not set at all';
}

Note that this is meaningless when used on anything which isn't a variable; i.e. empty (addslashes ($name)) has no meaning since it would be checking whether something which isn't a variable is a variable with a FALSE value.

floatval

(PHP 4 >= 4.2.0)

floatval -- Get float value of a variable

Description

float floatval ( mixed var)

Returns the float value of var.

Var may be any scalar type. You cannot use floatval() on arrays or objects.

$var = '122.34343The';
$float_value_of_var = floatval ($var);
print $float_value_of_var; // prints 122.34343

get_defined_vars

(PHP 4 >= 4.0.4)

get_defined_vars -- Returns an array of all defined variables

Description

array get_defined_vars ( void)

This function returns an multidimensional array containing a list of all defined variables, be them environment, server or user-defined variables.

$b = array(1,1,2,3,5,8);

$arr = get_defined_vars();

// print $b
print_r($arr["b"]);

// print path to the PHP interpreter (if used as a CGI)
// e.g. /usr/local/bin/php
echo $arr["_"];

// print the command-line paramaters if any
print_r($arr["argv"]);

// print all the server vars
print_r($arr["_SERVER"]);

// print all the available keys for the arrays of variables
print_r(array_keys(get_defined_vars()));

get_resource_type

(PHP 4 >= 4.0.2)

get_resource_type -- Returns the resource type

Description

string get_resource_type ( resource handle)

This function returns a string representing the type of the resource passed to it. If the paramater is not a valid resource, it generates an error.

$c = mysql_connect();
echo get_resource_type($c)."\n";
// prints: mysql link

$fp = fopen("foo","w");
echo get_resource_type($fp)."\n";
// prints: file

$doc = new_xmldoc("1.0");
echo get_resource_type($doc->doc)."\n";
// prints: domxml document

gettype

(PHP 3, PHP 4 )

gettype -- Get the type of a variable

Description

string gettype ( mixed var)

Returns the type of the PHP variable var.

Varování

Never use gettype() to test for a certain type, since the returned string may be subject to change in a future version. In addition, it is slow too, as it involves string comparision .

Instead, use the is_* functions.

Possibles values for the returned string are:

"boolean" (since PHP 4)
"integer"
"double" (for historical reasons "double" is returned in case of a float, and not simply "float")
"string"
"array"
"object"
"resource" (since PHP 4)
"NULL" (since PHP 4)
"user function" (PHP 3 only, deprecated)
"unknown type"

For PHP 4, you should use function_exists() and method_exists() to replace the prior usage of gettype() on a function.

import_request_variables

(PHP 4 >= 4.1.0)

import_request_variables -- Import GET/POST/Cookie variables into the global scope

Description

bool import_request_variables ( string types [, string prefix])

Imports GET/POST/Cookie variables into the global scope. It is useful if you disabled register_globals, but would like to see some variables in the global scope.

Using the types parameter, you can specify which request variables to import. You can use 'G', 'P' and 'C' characters respectively for GET, POST and Cookie. These characters are not case sensitive, so you can also use any combination of 'g', 'p' and 'c'. POST includes the POST uploaded file information. Note that the order of the letters matters, as when using "gp", the POST variables will overwrite GET variables with the same name. Any other letters than GPC are discarded.

The prefix parameter is used as a variable name prefix, prepended before all variable's name imported into the global scope. So if you have a GET value named "userid", and provide a prefix "pref_", then you'll get a global variable named $pref_userid.

If you're interested in importing other variables into the global scope, such as SERVER, consider using extract().

Poznámka: Although the prefix parameter is optional, you will get an E_NOTICE level error if you specify no prefix, or specify an empty string as a prefix. This is a possible security hazard. Notice level errors are not displayed using the default error reporting level.

// This will import GET and POST vars
// with an "rvar_" prefix
import_request_variables("gP", "rvar_");

print $rvar_foo;

intval

(PHP 3, PHP 4 )

intval -- Get integer value of a variable

Description

int intval ( mixed var [, int base])

Returns the integer value of var, using the specified base for the conversion (the default is base 10).

var may be any scalar type. You cannot use intval() on arrays or objects.

Poznámka: The base argument for intval() has no effect unless the var argument is a string.

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

is_double

(PHP 3, PHP 4 )

is_double -- Alias of is_float()

Description

This function is an alias of is_float().

is_float

(PHP 3, PHP 4 )

is_float -- Finds whether a variable is a float

Description

bool is_float ( mixed var)

Returns TRUE if var is a float, FALSE otherwise.

Poznámka: To test if a variable is a number or a numeric string (such as form input, which is always a string), you must use is_numeric().

is_int

(PHP 3, PHP 4 )

is_int -- Find whether a variable is an integer

Description

bool is_int ( mixed var)

Returns TRUE if var is an integer FALSE otherwise.

Poznámka: To test if a variable is a number or a numeric string (such as form input, which is always a string), you must use is_numeric().

This function is an alias of is_float().

is_resource

(PHP 4 )

is_resource -- Finds whether a variable is a resource

Description

bool is_resource ( mixed var)

is_resource() returns TRUE if the variable given by the var parameter is a resource, otherwise it returns FALSE.

See the documentation on the resource-type for more information.

is_scalar

(PHP 4 >= 4.0.5)

is_scalar -- Finds whether a variable is a scalar

Description

bool is_scalar ( mixed var)

is_scalar() returns TRUE if the variable given by the var parameter is a scalar, otherwise it returns FALSE.

Scalar variables are those containing an integer, float, string or boolean. Types array, object and resource or not scalar.

function show_var($var) {
    if (is_scalar($var)) {
        echo $var;
    } else {
        var_dump($var);
    }
}
$pi = 3.1416;
$proteins = array("hemoglobin", "cytochrome c oxidase", "ferredoxin");

show_var($pi);
// prints: 3.1416

show_var($proteins)
// prints:
// array(3) {
//   [0]=>
//   string(10) "hemoglobin"
//   [1]=>
//   string(20) "cytochrome c oxidase"
//   [2]=>
//   string(10) "ferredoxin"
// }

Poznámka: is_scalar() does not consider resource type values to be scalar as resources are abstract datatypes which are currently based on integers. This implementation detail should not be relied upon, as it may change.

is_string

(PHP 3, PHP 4 )

is_string -- Finds whether a variable is a string

Description

bool is_string ( mixed var)

Returns TRUE if var is a string, FALSE otherwise.

isset

(unknown)

isset -- Determine whether a variable is set

Description

bool isset ( mixed var [, mixed var [, ...]])

Poznámka: isset() is a language construct.

Returns TRUE if var exists; FALSE otherwise.

If a variable has been unset with unset(), it will no longer be isset(). isset() will return FALSE if testing a variable that has been set to NULL. Also note that a NULL byte ("\0") is not equivalent to the PHP NULL constant.

<?php
    $a = "test";
    $b = "anothertest";

    echo isset ($a); // TRUE
    echo isset ($a, $b); //TRUE

    unset ($a);
    echo isset ($a); // FALSE
    echo isset ($a, $b); //FALSE

$foo = NULL;
    print isset ($foo); // FALSE
?>

This also work for elements in arrays:

<?php
    $a = array ('test' => 1, 'hello' => null);

    echo isset ($a['test']);  // TRUE
    echo isset ($a['foo']);   // FALSE
    echo isset ($a['hello']); // FALSE
    echo array_key_exists('hello', $a); // TRUE
?>

print_r

(PHP 4 )

print_r -- Prints human-readable information about a variable

Description

void print_r ( mixed expression)

print_r() displays information about a variable in a way that's readable by humans. If given a string, integer or float, the value itself will be printed. If given an array, values will be presented in a format that shows keys and elements. Similar notation is used for objects.

Remember that print_r() will move the array pointer to the end. Use reset() to bring it back to beginning.

Tip: Jako pro cokoliv, co posílá své výsledky přímo do prohlížeče, můžete použít funkce pro řízení výstupu k zachycení výstupu této funkce a jeho uložení - například - do řetězce (string).

<pre>
<?php
    $a = array ('a' => 'apple', 'b' => 'banana', 'c' => array ('x','y','z'));
    print_r ($a);
?>
</pre>

Which will output:

<pre> Array ( [a] => apple [b] => banana [c] => Array ( [0] => x [1] => y [2] => z ) ) </pre>

Poznámka: Prior to PHP 4.0.4, print_r() will continue forever if given an array or object that contains a direct or indirect reference to itself. An example is print_r($GLOBALS) because $GLOBALS is itself a global variable that contains a reference to itself.

serialize

(PHP 3>= 3.0.5, PHP 4 )

serialize -- Generates a storable representation of a value

Description

string serialize ( mixed value)

serialize() returns a string containing a byte-stream representation of value that can be stored anywhere.

This is useful for storing or passing PHP values around without losing their type and structure.

To make the serialized string into a PHP value again, use unserialize(). serialize() handles all types, except the resource-type. You can even serialize() arrays that contain references to itself. References inside the array/object you are serialize()ing will also be stored.

Poznámka: In PHP 3, object properties will be serialized, but methods are lost. PHP 4 removes that limitation and restores both properties and methods. Please see the Serializing Objects section of Classes and Objects for more information.

Příklad 1. serialize() example

// $session_data contains a multi-dimensional array with session // information for the current user. We use serialize() to store // it in a database at the end of the request. $conn = odbc_connect ("webdb", "php", "chicken"); $stmt = odbc_prepare ($conn, "UPDATE sessions SET data = ? WHERE id = ?"); $sqldata = array (serialize($session_data), $PHP_AUTH_USER); if (!odbc_execute ($stmt, &$sqldata)) { $stmt = odbc_prepare($conn, "INSERT INTO sessions (id, data) VALUES(?, ?)"); if (!odbc_execute($stmt, &$sqldata)) { /* Something went wrong. Bitch, whine and moan. */ } }

settype

(PHP 3, PHP 4 )

settype -- Set the type of a variable

Description

bool settype ( mixed var, string type)

Set the type of variable var to type.

Possibles values of type are:

"boolean" (or, since PHP 4.2.0, "bool")
"integer" (or, since PHP 4.2.0, "int")
"float" (only possible since PHP 4.2.0, for older versions use the deprecated variant "double")
"string"
"array"
"object"
"null" (since PHP 4.2.0)

Returns TRUE if successful; otherwise returns FALSE.

Příklad 1. settype() example

$foo = "5bar"; // string $bar = true; // boolean settype($foo, "integer"); // $foo is now 5 (integer) settype($bar, "string"); // $bar is now "1" (string)

See also gettype(), type-casting and type-juggling.

strval

(PHP 3, PHP 4 )

strval -- Get string value of a variable

Description

string strval ( mixed var)

Returns the string value of var. See the documentation on string for more information on converting to string.

var may be any scalar type. You cannot use strval() on arrays or objects.

unserialize

(PHP 3>= 3.0.5, PHP 4 )

unserialize -- Creates a PHP value from a stored representation

Description

mixed unserialize ( string str)

unserialize() takes a single serialized variable (see serialize()) and converts it back into a PHP value. The converted value is returned, and can be an integer, float, string, array or object.

Poznámka: It's possible to set a callback-function which will be called, if an undefined class should be instanciated during unserializing. (to prevent getting an incomplete object "__PHP_Incomplete_Class".) Use your php.ini, ini_set() or .htaccess-file to define 'unserialize_callback_func'. Everytime an undefined class should be instanciated, it'll be called. To disable this feature just empty this setting.

Příklad 1. unserialize_callback_func example

$serialized_object='O:1:"a":1:{s:5:"value";s:3:"100";}'; ini_set('unserialize_callback_func','mycallback'); // set your callback_function function mycallback($classname) { // just include a file containing your classdefinition // you get $classname to figure out which classdefinition is required }

Poznámka: In PHP 3, methods are not preserved when unserializing a serialized object. PHP 4 removes that limitation and restores both properties and methods. Please see the Serializing Objects section of Classes and Objects or more information.

Příklad 2. unserialize() example

// Here, we use unserialize() to load session data to the // $session_data array from the string selected from a database. // This example complements the one described with serialize(). $conn = odbc_connect ("webdb", "php", "chicken"); $stmt = odbc_prepare ($conn, "SELECT data FROM sessions WHERE id = ?"); $sqldata = array ($PHP_AUTH_USER); if (!odbc_execute ($stmt, &$sqldata) || !odbc_fetch_into ($stmt, &$tmp)) { // if the execute or fetch fails, initialize to empty array $session_data = array(); } else { // we should now have the serialized data in $tmp[0]. $session_data = unserialize ($tmp[0]); if (!is_array ($session_data)) { // something went wrong, initialize to empty array $session_data = array(); } }

unset

(unknown)

unset -- Unset a given variable

Description

void unset ( mixed var [, mixed var [, ...]])

Poznámka: unset() is a language construct.

unset() destroys the specified variables. Note that in PHP 3, unset() will always return TRUE (actually, the integer value 1). In PHP 4, however, unset() is no longer a true function: it is now a statement. As such no value is returned, and attempting to take the value of unset() results in a parse error.

Příklad 1. unset() example

// destroy a single variable unset ($foo); // destroy a single element of an array unset ($bar['quux']); // destroy more than one variable unset ($foo1, $foo2, $foo3);

The behavior of unset() inside of a function can vary depending on what type of variable you are attempting to destroy.

If a globalized variable is unset() inside of a function, only the local variable is destroyed. The variable in the calling environment will retain the same value as before unset() was called.

function destroy_foo() {
    global $foo;
    unset($foo);
}

$foo = 'bar';
destroy_foo();
echo $foo;

The above example would output:

bar

If a variable that is PASSED BY REFERENCE is unset() inside of a function, only the local variable is destroyed. The variable in the calling environment will retain the same value as before unset() was called.

function foo(&$bar) {
    unset($bar);
    $bar = "blah";
}

$bar = 'something';
echo "$bar\n";

foo($bar);
echo "$bar\n";

The above example would output:

something
something

If a static variable is unset() inside of a function, unset() destroyes the variable and all its references.

function foo() {
    static $a;
    $a++;
    echo "$a\n";
    unset($a);
}

foo();
foo();
foo();

The above example would output:

1
2
3

If you would like to unset() a global variable inside of a function, you can use the $GLOBALS array to do so:

function foo() {
    unset($GLOBALS['bar']);
}

$bar = "something";
foo();

var_dump

(PHP 3>= 3.0.5, PHP 4 )

var_dump -- Dumps information about a variable

Description

void var_dump ( mixed expression [, mixed expression [, ...]])

This function returns structured information about one or more expressions that includes its type and value. Arrays are explored recursively with values indented to show structure.

Tip: Jako pro cokoliv, co posílá své výsledky přímo do prohlížeče, můžete použít funkce pro řízení výstupu k zachycení výstupu této funkce a jeho uložení - například - do řetězce (string).

Compare var_dump() to print_r().

<pre>
<?php
$a = array (1, 2, array ("a", "b", "c"));
var_dump ($a);

/* output:
array(3) {
  [0]=>
  int(1)
  [1]=>
  int(2)
  [2]=>
  array(3) {
    [0]=>
    string(1) "a"
    [1]=>
    string(1) "b"
    [2]=>
    string(1) "c"
  }
}

*/

$b = 3.1;
$c = TRUE;
var_dump($b,$c);

/* output:
float(3.1)
bool(true)

*/
?>
</pre>

var_export

(PHP 4 >= 4.2.0)

var_export -- Outputs or returns a string representation of a variable

Description

mixed var_export ( mixed expression [, bool return])

This function returns structured information about the variable that is passed to this function. It is similar to var_dump() with the exception that the returned representation is valid PHP code.

You can also return the variable representation by using TRUE as second parameter to this function.

Compare var_export() to var_dump().

<pre>
<?php
$a = array (1, 2, array ("a", "b", "c"));
var_export ($a);

/* output:
array (
  0 => 1,
  1 => 2,
  2 => 
  array (
    0 => 'a',
    1 => 'b',
    2 => 'c',
  ),
)
*/

$b = 3.1;
$v = var_export($b, TRUE);
echo $v;

/* output:
3.1
*/
?>
</pre>

CII. vpopmail functions

Obsah
vpopmail_add_alias_domain_ex -- Add alias to an existing virtual domain
vpopmail_add_alias_domain -- Add an alias for a virtual domain
vpopmail_add_domain_ex -- Add a new virtual domain
vpopmail_add_domain -- Add a new virtual domain
vpopmail_add_user -- Add a new user to the specified virtual domain
vpopmail_alias_add -- insert a virtual alias
vpopmail_alias_del_domain -- deletes all virtual aliases of a domain
vpopmail_alias_del -- deletes all virtual aliases of a user
vpopmail_alias_get_all -- get all lines of an alias for a domain
vpopmail_alias_get -- get all lines of an alias for a domain
vpopmail_auth_user -- Attempt to validate a username/domain/password. Returns true/false
vpopmail_del_domain_ex -- Delete a virtual domain
vpopmail_del_domain -- Delete a virtual domain
vpopmail_del_user -- Delete a user from a virtual domain
vpopmail_error -- Get text message for last vpopmail error. Returns string
vpopmail_passwd -- Change a virtual user's password
vpopmail_set_user_quota -- Sets a virtual user's quota

CIII. W32api functions

Úvod

This extension is a generic extension API to DLLs. This was originally written to allow access to the Win32 API from PHP, although you can also access other functions exported via other DLLs.

Currently supported types are generic PHP types (strings, booleans, floats, integers and nulls) and types you define with w32api_deftype().

Varování

Požadavky

This extension will only work on Windows systems.

Instalace

K používání těchto funkcí není třeba žádná instalace, jsou součástí jádra PHP.

Konfigurace běhu

Toto rozšíření nemá definováno žádné konfigurační direktivy.

Typy prostředků

This extension defines one resource type, used for user defined types. The name of this resource is "dynaparm".

Předdefinované konstanty

Tyto konstanty jsou definovány tímto rozšířením a budou k dispozici pouze tehdy, bylo-li rozšíření zkompilováno společně s PHP nebo dynamicky zavedeno za běhu.

DC_MICROSOFT (integer)
DC_BORLAND (integer)
DC_CALL_CDECL (integer)
DC_CALL_STD (integer)
DC_RETVAL_MATH4 (integer)
DC_RETVAL_MATH8 (integer)
DC_CALL_STD_BO (integer)
DC_CALL_STD_MS (integer)
DC_CALL_STD_M8 (integer)
DC_FLAG_ARGPTR (integer)

Příklady

This example gets the amount of time the system has been running and displays it in a message box.

Příklad 1. Get the uptime and display it in a message box

<?php
// Define constants needed, taken from
// Visual Studio/Tools/Winapi/WIN32API.txt
define("MB_OK", 0);

// Load the extension in
dl("php_w32api.dll");

// Register the GetTickCount function from kernel32.dll
w32api_register_function("kernel32.dll", 
                         "GetTickCount",
                         "long");
                         
// Register the MessageBoxA function from User32.dll
w32api_register_function("User32.dll",
                         "MessageBoxA",
                         "long");

// Get uptime information
$ticks = GetTickCount();

// Convert it to a nicely displayable text
$secs  = floor($ticks / 1000);
$mins  = floor($secs / 60);
$hours = floor($mins / 60);

$str = sprintf("You have been using your computer for:".
                "\r\n %d Milliseconds, or \r\n %d Seconds".
                "or \r\n %d mins or\r\n %d hours %d mins.",
                $ticks,
                $secs,
                $mins,
                $hours,
                $mins - ($hours*60));

// Display a message box with only an OK button and the uptime text
MessageBoxA(NULL, 
            $str, 
            "Uptime Information", 
            MB_OK);
?>

Obsah
w32api_deftype -- Defines a type for use with other w32api_functions
w32api_init_dtype -- Creates an instance of the data type typename and fills it with the values passed
w32api_invoke_function -- Invokes function funcname with the arguments passed after the function name
w32api_register_function -- Registers function function_name from library with PHP
w32api_set_call_method -- Sets the calling method used

CIV. WDDX funkce

Tyto funkce jsou určeny pro práci s WDDX.

Pokud chcete používat WDDX, budete muset nainstalovat expat knihovnu (která je u Apache 1.3.7 a vyšších) a zkompilovat PHP s --with-xml a --enable-wddx.

Pozn.: všechny funkce které serializují proměnné používají první element pole k rozhodnutí jestli se toto pole serializuje do pole nebo struktury. Pokud má první element řetězec jako index, serializuje se do struktury, jinak do pole.

Příklad 1. Serializace jediné hodnoty

<?php print wddx_serialize_value("PHP to WDDX packet example", "PHP packet"); ?>

Tato ukázka vytvoří:

<wddxPacket version='1.0'><header comment='PHP packet'/><data>
<string>PHP to WDDX packet example</string></data></wddxPacket>

Příklad 2. Použití inkrementálních paketů

<?php
$pi = 3.1415926;
$packet_id = wddx_packet_start("PHP");
wddx_add_vars($packet_id, "pi");

/* Suppose $cities came from database */
$cities = array("Austin", "Novato", "Seattle");
wddx_add_vars($packet_id, "cities");

$packet = wddx_packet_end($packet_id);
print $packet;
?>

Tato ukázka vytvoří:

<wddxPacket version='1.0'><header comment='PHP'/><data><struct>
<var name='pi'><number>3.1415926</number></var><var name='cities'>
<array length='3'><string>Austin</string><string>Novato</string>
<string>Seattle</string></array></var></struct></data></wddxPacket>

Obsah
wddx_add_vars -- Přidat proměnné do WDDX paketu s určeným ID
wddx_deserialize -- Deserializovat WDDX paket
wddx_packet_end -- Ukončit WDDX paket se zadaným ID
wddx_packet_start -- Začít nový WDDX paket obsahující strukturu
wddx_serialize_value -- Serializovat jedinou hodnotu do WDDX paketu
wddx_serialize_vars -- Serializovat proměnné do WDDX paketu

wddx_serialize_vars() přijímá proměnný počet argumentů, každý z nich může být buď řetězec obsahující název proměnné, nebo pole názvů proměnných, nebo jiné pole atd.

Příklad 1. wddx_serialize_vars example

<?php $a = 1; $b = 5.5; $c = array("blue", "orange", "violet"); $d = "colors"; $clvars = array("c", "d"); print wddx_serialize_vars("a", "b", $clvars); ?>

Výše uvedená ukázka vytvoří:

<wddxPacket version='1.0'><header/><data><struct><var name='a'><number>1</number></var> <var name='b'><number>5.5</number></var><var name='c'><array length='3'> <string>blue</string><string>orange</string><string>violet</string></array></var> <var name='d'><string>colors</string></var></struct></data></wddxPacket>

CV. XML parser functions

Introduction

About XML

XML (eXtensible Markup Language) is a data format for structured document interchange on the Web. It is a standard defined by The World Wide Web consortium (W3C). Information about XML and related technologies can be found at http://www.w3.org/XML/.

Installation

This extension uses expat, which can be found at http://www.jclark.com/xml/. The Makefile that comes with expat does not build a library by default, you can use this make rule for that:

libexpat.a: $(OBJS) ar -rc $@ $(OBJS) ranlib $@
A source RPM package of expat can be found at http://sourceforge.net/projects/expat/.

Note that if you are using Apache-1.3.7 or later, you already have the required expat library. Simply configure PHP using --with-xml (without any additional path) and it will automatically use the expat library built into Apache.

On UNIX, run configure with the --with-xml option. The expat library should be installed somewhere your compiler can find it. If you compile PHP as a module for Apache 1.3.9 or later, PHP will automatically use the bundled expat library from Apache. You may need to set CPPFLAGS and LDFLAGS in your environment before running configure if you have installed expat somewhere exotic.

Build PHP. Tada! That should be it.

About This Extension

This PHP extension implements support for James Clark's expat in PHP. This toolkit lets you parse, but not validate, XML documents. It supports three source character encodings also provided by PHP: US-ASCII, ISO-8859-1 and UTF-8. UTF-16 is not supported.

This extension lets you create XML parsers and then define handlers for different XML events. Each XML parser also has a few parameters you can adjust.

The XML event handlers defined are:

Tabulka 1. Supported XML handlers

PHP function to set handler	Event description
xml_set_element_handler()	Element events are issued whenever the XML parser encounters start or end tags. There are separate handlers for start tags and end tags.
xml_set_character_data_handler()	Character data is roughly all the non-markup contents of XML documents, including whitespace between tags. Note that the XML parser does not add or remove any whitespace, it is up to the application (you) to decide whether whitespace is significant.
xml_set_processing_instruction_handler()	PHP programmers should be familiar with processing instructions (PIs) already. <?php ?> is a processing instruction, where `php` is called the "PI target". The handling of these are application-specific, except that all PI targets starting with "XML" are reserved.
xml_set_default_handler()	What goes not to another handler goes to the default handler. You will get things like the XML and document type declarations in the default handler.
xml_set_unparsed_entity_decl_handler()	This handler will be called for declaration of an unparsed (NDATA) entity.
xml_set_notation_decl_handler()	This handler is called for declaration of a notation.
xml_set_external_entity_ref_handler()	This handler is called when the XML parser finds a reference to an external parsed general entity. This can be a reference to a file or URL, for example. See the external entity example for a demonstration.

Case Folding

The element handler functions may get their element names case-folded. Case-folding is defined by the XML standard as "a process applied to a sequence of characters, in which those identified as non-uppercase are replaced by their uppercase equivalents". In other words, when it comes to XML, case-folding simply means uppercasing.

By default, all the element names that are passed to the handler functions are case-folded. This behaviour can be queried and controlled per XML parser with the xml_parser_get_option() and xml_parser_set_option() functions, respectively.

Error Codes

The following constants are defined for XML error codes (as returned by xml_parse()):

XML_ERROR_NONE

XML_ERROR_NO_MEMORY

XML_ERROR_SYNTAX

XML_ERROR_NO_ELEMENTS

XML_ERROR_INVALID_TOKEN

XML_ERROR_UNCLOSED_TOKEN

XML_ERROR_PARTIAL_CHAR

XML_ERROR_TAG_MISMATCH

XML_ERROR_DUPLICATE_ATTRIBUTE

XML_ERROR_JUNK_AFTER_DOC_ELEMENT

XML_ERROR_PARAM_ENTITY_REF

XML_ERROR_UNDEFINED_ENTITY

XML_ERROR_RECURSIVE_ENTITY_REF

XML_ERROR_ASYNC_ENTITY

XML_ERROR_BAD_CHAR_REF

XML_ERROR_BINARY_ENTITY_REF

XML_ERROR_ATTRIBUTE_EXTERNAL_ENTITY_REF

XML_ERROR_MISPLACED_XML_PI

XML_ERROR_UNKNOWN_ENCODING

XML_ERROR_INCORRECT_ENCODING

XML_ERROR_UNCLOSED_CDATA_SECTION

XML_ERROR_EXTERNAL_ENTITY_HANDLING

Character Encoding

PHP's XML extension supports the Unicode character set through different character encodings. There are two types of character encodings, source encoding and target encoding. PHP's internal representation of the document is always encoded with UTF-8.

Source encoding is done when an XML document is parsed. Upon creating an XML parser, a source encoding can be specified (this encoding can not be changed later in the XML parser's lifetime). The supported source encodings are ISO-8859-1, US-ASCII and UTF-8. The former two are single-byte encodings, which means that each character is represented by a single byte. UTF-8 can encode characters composed by a variable number of bits (up to 21) in one to four bytes. The default source encoding used by PHP is ISO-8859-1.

Target encoding is done when PHP passes data to XML handler functions. When an XML parser is created, the target encoding is set to the same as the source encoding, but this may be changed at any point. The target encoding will affect character data as well as tag names and processing instruction targets.

If the XML parser encounters characters outside the range that its source encoding is capable of representing, it will return an error.

If PHP encounters characters in the parsed XML document that can not be represented in the chosen target encoding, the problem characters will be "demoted". Currently, this means that such characters are replaced by a question mark.

Some Examples

Here are some example PHP scripts parsing XML documents.

XML Element Structure Example

This first example displays the stucture of the start elements in a document with indentation.

Příklad 1. Show XML Element Structure

$file = "data.xml"; $depth = array(); function startElement($parser, $name, $attrs) { global $depth; for ($i = 0; $i < $depth[$parser]; $i++) { print " "; } print "$name\n"; $depth[$parser]++; } function endElement($parser, $name) { global $depth; $depth[$parser]--; } $xml_parser = xml_parser_create(); xml_set_element_handler($xml_parser, "startElement", "endElement"); if (!($fp = fopen($file, "r"))) { die("could not open XML input"); } while ($data = fread($fp, 4096)) { if (!xml_parse($xml_parser, $data, feof($fp))) { die(sprintf("XML error: %s at line %d", xml_error_string(xml_get_error_code($xml_parser)), xml_get_current_line_number($xml_parser))); } } xml_parser_free($xml_parser);

XML Tag Mapping Example

Příklad 2. Map XML to HTML

This example maps tags in an XML document directly to HTML tags. Elements not found in the "map array" are ignored. Of course, this example will only work with a specific XML document type.

$file = "data.xml"; $map_array = array( "BOLD" => "B", "EMPHASIS" => "I", "LITERAL" => "TT" ); function startElement($parser, $name, $attrs) { global $map_array; if ($htmltag = $map_array[$name]) { print "<$htmltag>"; } } function endElement($parser, $name) { global $map_array; if ($htmltag = $map_array[$name]) { print "</$htmltag>"; } } function characterData($parser, $data) { print $data; } $xml_parser = xml_parser_create(); // use case-folding so we are sure to find the tag in $map_array xml_parser_set_option($xml_parser, XML_OPTION_CASE_FOLDING, true); xml_set_element_handler($xml_parser, "startElement", "endElement"); xml_set_character_data_handler($xml_parser, "characterData"); if (!($fp = fopen($file, "r"))) { die("could not open XML input"); } while ($data = fread($fp, 4096)) { if (!xml_parse($xml_parser, $data, feof($fp))) { die(sprintf("XML error: %s at line %d", xml_error_string(xml_get_error_code($xml_parser)), xml_get_current_line_number($xml_parser))); } } xml_parser_free($xml_parser);

XML External Entity Example

This example highlights XML code. It illustrates how to use an external entity reference handler to include and parse other documents, as well as how PIs can be processed, and a way of determining "trust" for PIs containing code.

XML documents that can be used for this example are found below the example (xmltest.xml and xmltest2.xml.)

Příklad 3. External Entity Example

<?php $file = "xmltest.xml"; function trustedFile($file) { // only trust local files owned by ourselves if (!eregi("^([a-z]+)://", $file) && fileowner($file) == getmyuid()) { return true; } return false; } function startElement($parser, $name, $attribs) { print "<<font color=\"#0000cc\">$name</font>"; if (sizeof($attribs)) { while (list($k, $v) = each($attribs)) { print " <font color=\"#009900\">$k</font>=\"<font color=\"#990000\">$v</font>\""; } } print ">"; } function endElement($parser, $name) { print "</<font color=\"#0000cc\">$name</font>>"; } function characterData($parser, $data) { print "<b>$data</b>"; } function PIHandler($parser, $target, $data) { switch (strtolower($target)) { case "php": global $parser_file; // If the parsed document is "trusted", we say it is safe // to execute PHP code inside it. If not, display the code // instead. if (trustedFile($parser_file[$parser])) { eval($data); } else { printf("Untrusted PHP code: <i>%s</i>", htmlspecialchars($data)); } break; } } function defaultHandler($parser, $data) { if (substr($data, 0, 1) == "&" && substr($data, -1, 1) == ";") { printf('<font color="#aa00aa">%s</font>', htmlspecialchars($data)); } else { printf('<font size="-1">%s</font>', htmlspecialchars($data)); } } function externalEntityRefHandler($parser, $openEntityNames, $base, $systemId, $publicId) { if ($systemId) { if (!list($parser, $fp) = new_xml_parser($systemId)) { printf("Could not open entity %s at %s\n", $openEntityNames, $systemId); return false; } while ($data = fread($fp, 4096)) { if (!xml_parse($parser, $data, feof($fp))) { printf("XML error: %s at line %d while parsing entity %s\n", xml_error_string(xml_get_error_code($parser)), xml_get_current_line_number($parser), $openEntityNames); xml_parser_free($parser); return false; } } xml_parser_free($parser); return true; } return false; } function new_xml_parser($file) { global $parser_file; $xml_parser = xml_parser_create(); xml_parser_set_option($xml_parser, XML_OPTION_CASE_FOLDING, 1); xml_set_element_handler($xml_parser, "startElement", "endElement"); xml_set_character_data_handler($xml_parser, "characterData"); xml_set_processing_instruction_handler($xml_parser, "PIHandler"); xml_set_default_handler($xml_parser, "defaultHandler"); xml_set_external_entity_ref_handler($xml_parser, "externalEntityRefHandler"); if (!($fp = @fopen($file, "r"))) { return false; } if (!is_array($parser_file)) { settype($parser_file, "array"); } $parser_file[$xml_parser] = $file; return array($xml_parser, $fp); } if (!(list($xml_parser, $fp) = new_xml_parser($file))) { die("could not open XML input"); } print "<pre>"; while ($data = fread($fp, 4096)) { if (!xml_parse($xml_parser, $data, feof($fp))) { die(sprintf("XML error: %s at line %d\n", xml_error_string(xml_get_error_code($xml_parser)), xml_get_current_line_number($xml_parser))); } } print "</pre>"; print "parse complete\n"; xml_parser_free($xml_parser); ?>

Příklad 4. xmltest.xml

<?xml version='1.0'?> <!DOCTYPE chapter SYSTEM "/just/a/test.dtd" [ <!ENTITY plainEntity "FOO entity"> <!ENTITY systemEntity SYSTEM "xmltest2.xml"> ]> <chapter> <TITLE>Title &plainEntity;</TITLE> <para> <informaltable> <tgroup cols="3"> <tbody> <row><entry>a1</entry><entry morerows="1">b1</entry><entry>c1</entry></row> <row><entry>a2</entry><entry>c2</entry></row> <row><entry>a3</entry><entry>b3</entry><entry>c3</entry></row> </tbody> </tgroup> </informaltable> </para> &systemEntity; <section id="about"> <title>About this Document</title> <para>  <?php print 'Hi! This is PHP version '.phpversion(); ?> </para> </section> </chapter>

This file is included from xmltest.xml:

Příklad 5. xmltest2.xml

<?xml version="1.0"?> <!DOCTYPE foo [ <!ENTITY testEnt "test entity"> ]> <foo> <element attrib="value"/> &testEnt; <?php print "This is some more PHP code being executed."; ?> </foo>

Obsah
utf8_decode -- Converts a string with ISO-8859-1 characters encoded with UTF-8 to single-byte ISO-8859-1.
utf8_encode -- encodes an ISO-8859-1 string to UTF-8
xml_error_string -- get XML parser error string
xml_get_current_byte_index -- get current byte index for an XML parser
xml_get_current_column_number -- Get current column number for an XML parser
xml_get_current_line_number -- get current line number for an XML parser
xml_get_error_code -- get XML parser error code
xml_parse_into_struct -- Parse XML data into an array structure
xml_parse -- start parsing an XML document
xml_parser_create_ns -- Create an XML parser
xml_parser_create -- create an XML parser
xml_parser_free -- Free an XML parser
xml_parser_get_option -- get options from an XML parser
xml_parser_set_option -- set options in an XML parser
xml_set_character_data_handler -- set up character data handler
xml_set_default_handler -- set up default handler
xml_set_element_handler -- set up start and end element handlers
xml_set_end_namespace_decl_handler -- Set up character data handler
xml_set_external_entity_ref_handler -- set up external entity reference handler
xml_set_notation_decl_handler -- set up notation declaration handler
xml_set_object -- Use XML Parser within an object
xml_set_processing_instruction_handler -- Set up processing instruction (PI) handler
xml_set_start_namespace_decl_handler -- Set up character data handler
xml_set_unparsed_entity_decl_handler -- Set up unparsed entity declaration handler

utf8_decode

(PHP 3>= 3.0.6, PHP 4 )

utf8_decode -- Converts a string with ISO-8859-1 characters encoded with UTF-8 to single-byte ISO-8859-1.

Description

string utf8_decode ( string data)

This function decodes data, assumed to be UTF-8 encoded, to ISO-8859-1.

See utf8_encode() for an explaination of UTF-8 encoding.

utf8_encode

(PHP 3>= 3.0.6, PHP 4 )

utf8_encode -- encodes an ISO-8859-1 string to UTF-8

Description

string utf8_encode ( string data)

This function encodes the string data to UTF-8, and returns the encoded version. UTF-8 is a standard mechanism used by Unicode for encoding wide character values into a byte stream. UTF-8 is transparent to plain ASCII characters, is self-synchronized (meaning it is possible for a program to figure out where in the bytestream characters start) and can be used with normal string comparison functions for sorting and such. PHP encodes UTF-8 characters in up to four bytes, like this:

Tabulka 1. UTF-8 encoding

bytes	bits	representation
1	7	0bbbbbbb
2	11	110bbbbb 10bbbbbb
3	16	1110bbbb 10bbbbbb 10bbbbbb
4	21	11110bbb 10bbbbbb 10bbbbbb 10bbbbbb

Each b represents a bit that can be used to store character data.

xml_error_string

(PHP 3>= 3.0.6, PHP 4 )

xml_error_string -- get XML parser error string

Description

string xml_error_string ( int code)

code: An error code from xml_get_error_code().

Returns a string with a textual description of the error code code, or FALSE if no description was found.

xml_get_current_byte_index

(PHP 3>= 3.0.6, PHP 4 )

xml_get_current_byte_index -- get current byte index for an XML parser

Description

int xml_get_current_byte_index ( resource parser)

parser: A reference to the XML parser to get byte index from.

This function returns FALSE if parser does not refer to a valid parser, or else it returns which byte index the parser is currently at in its data buffer (starting at 0).

xml_get_current_column_number

(PHP 3>= 3.0.6, PHP 4 )

xml_get_current_column_number -- Get current column number for an XML parser

Description

int xml_get_current_column_number ( resource parser)

parser: A reference to the XML parser to get column number from.

This function returns FALSE if parser does not refer to a valid parser, or else it returns which column on the current line (as given by xml_get_current_line_number()) the parser is currently at.

xml_get_current_line_number

(PHP 3>= 3.0.6, PHP 4 )

xml_get_current_line_number -- get current line number for an XML parser

Description

int xml_get_current_line_number ( resource parser)

parser: A reference to the XML parser to get line number from.

This function returns FALSE if parser does not refer to a valid parser, or else it returns which line the parser is currently at in its data buffer.

xml_get_error_code

(PHP 3>= 3.0.6, PHP 4 )

xml_get_error_code -- get XML parser error code

Description

int xml_get_error_code ( resource parser)

parser: A reference to the XML parser to get error code from.

This function returns FALSE if parser does not refer to a valid parser, or else it returns one of the error codes listed in the error codes section.

xml_parse_into_struct

(PHP 3>= 3.0.8, PHP 4 )

xml_parse_into_struct -- Parse XML data into an array structure

Description

int xml_parse_into_struct ( resource parser, string data, array &values, array &index)

This function parses an XML file into 2 parallel array structures, one (index) containing pointers to the location of the appropriate values in the values array. These last two parameters must be passed by reference.

Below is an example that illustrates the internal structure of the arrays being generated by the function. We use a simple note tag embeded inside a para tag, and then we parse this an print out the structures generated:

$simple = "<para><note>simple note</note></para>";
$p = xml_parser_create();
xml_parse_into_struct($p,$simple,$vals,$index);
xml_parser_free($p);
echo "Index array\n";
print_r($index);
echo "\nVals array\n";
print_r($vals);

When we run that code, the output will be:

Index array
Array
(
    [PARA] => Array
        (
            [0] => 0
            [1] => 2
        )

    [NOTE] => Array
        (
            [0] => 1
        )

)

Vals array
Array
(
    [0] => Array
        (
            [tag] => PARA
            [type] => open
            [level] => 1
        )

    [1] => Array
        (
            [tag] => NOTE
            [type] => complete
            [level] => 2
            [value] => simple note
        )

    [2] => Array
        (
            [tag] => PARA
            [type] => close
            [level] => 1
        )

)

Event-driven parsing (based on the expat library) can get complicated when you have an XML document that is complex. This function does not produce a DOM style object, but it generates structures amenable of being transversed in a tree fashion. Thus, we can create objects representing the data in the XML file easily. Let's consider the following XML file representing a small database of aminoacids information:

Příklad 1. moldb.xml - small database of molecular information

<?xml version="1.0"?> <moldb> <molecule> <name>Alanine</name> <symbol>ala</symbol> <code>A</code> <type>hydrophobic</type> </molecule> <molecule> <name>Lysine</name> <symbol>lys</symbol> <code>K</code> <type>charged</type> </molecule> </moldb>
And some code to parse the document and generate the appropriate objects:

Příklad 2. parsemoldb.php - parses moldb.xml into and array of molecular objects

<?php class AminoAcid { var $name; // aa name var $symbol; // three letter symbol var $code; // one letter code var $type; // hydrophobic, charged or neutral function AminoAcid ($aa) { foreach ($aa as $k=>$v) $this->$k = $aa[$k]; } } function readDatabase($filename) { // read the xml database of aminoacids $data = implode("",file($filename)); $parser = xml_parser_create(); xml_parser_set_option($parser,XML_OPTION_CASE_FOLDING,0); xml_parser_set_option($parser,XML_OPTION_SKIP_WHITE,1); xml_parse_into_struct($parser,$data,$values,$tags); xml_parser_free($parser); // loop through the structures foreach ($tags as $key=>$val) { if ($key == "molecule") { $molranges = $val; // each contiguous pair of array entries are the // lower and upper range for each molecule definition for ($i=0; $i < count($molranges); $i+=2) { $offset = $molranges[$i] + 1; $len = $molranges[$i + 1] - $offset; $tdb[] = parseMol(array_slice($values, $offset, $len)); } } else { continue; } } return $tdb; } function parseMol($mvalues) { for ($i=0; $i < count($mvalues); $i++) $mol[$mvalues[$i]["tag"]] = $mvalues[$i]["value"]; return new AminoAcid($mol); } $db = readDatabase("moldb.xml"); echo "** Database of AminoAcid objects:\n"; print_r($db); ?>
After executing parsemoldb.php, the variable $db contains an array of AminoAcid objects, and the output of the script confirms that:

** Database of AminoAcid objects:
Array
(
    [0] => aminoacid Object
        (
            [name] => Alanine
            [symbol] => ala
            [code] => A
            [type] => hydrophobic
        )

    [1] => aminoacid Object
        (
            [name] => Lysine
            [symbol] => lys
            [code] => K
            [type] => charged
        )

)

xml_parse

(PHP 3>= 3.0.6, PHP 4 )

xml_parse -- start parsing an XML document

Description

bool xml_parse ( resource parser, string data [, bool is_final])

parser: A reference to the XML parser to use.
data: Chunk of data to parse. A document may be parsed piece-wise by calling xml_parse() several times with new data, as long as the is_final parameter is set and TRUE when the last data is parsed.
is_final (optional): If set and TRUE, data is the last piece of data sent in this parse.

When the XML document is parsed, the handlers for the configured events are called as many times as necessary, after which this function returns TRUE or FALSE.

TRUE is returned if the parse was successful, FALSE if it was not successful, or if parser does not refer to a valid parser. For unsuccessful parses, error information can be retrieved with xml_get_error_code(), xml_error_string(), xml_get_current_line_number(), xml_get_current_column_number() and xml_get_current_byte_index().

xml_parser_create_ns

(PHP 4 >= 4.0.5)

xml_parser_create_ns -- Create an XML parser

Description

resource xml_parser_create_ns ( [string encoding [, string sep]])

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

xml_parser_create

(PHP 3>= 3.0.6, PHP 4 )

xml_parser_create -- create an XML parser

Description

resource xml_parser_create ( [string encoding])

encoding (optional)

Which character encoding the parser should use. The following character encodings are supported:

ISO-8859-1 (default)

US-ASCII

UTF-8

This function creates an XML parser and returns a handle for use by other XML functions. Returns FALSE on failure.

xml_parser_free

(PHP 3>= 3.0.6, PHP 4 )

xml_parser_free -- Free an XML parser

Description

bool xml_parser_free ( resource parser)

parser: A reference to the XML parser to free.

This function returns FALSE if parser does not refer to a valid parser, or else it frees the parser and returns TRUE.

xml_parser_get_option

(PHP 3>= 3.0.6, PHP 4 )

xml_parser_get_option -- get options from an XML parser

Description

mixed xml_parser_get_option ( resource parser, int option)

parser: A reference to the XML parser to get an option from.
option: Which option to fetch. See xml_parser_set_option() for a list of options.

This function returns FALSE if parser does not refer to a valid parser, or if the option could not be set. Else the option's value is returned.

See xml_parser_set_option() for the list of options.

xml_parser_set_option

(PHP 3>= 3.0.6, PHP 4 )

xml_parser_set_option -- set options in an XML parser

Description

bool xml_parser_set_option ( resource parser, int option, mixed value)

parser: A reference to the XML parser to set an option in.
option: Which option to set. See below.
value: The option's new value.

This function returns FALSE if parser does not refer to a valid parser, or if the option could not be set. Else the option is set and TRUE is returned.

The following options are available:

Tabulka 1. XML parser options

Option constant	Data type	Description
XML_OPTION_CASE_FOLDING	integer	Controls whether case-folding is enabled for this XML parser. Enabled by default.
XML_OPTION_TARGET_ENCODING	string	Sets which target encoding to use in this XML parser. By default, it is set to the same as the source encoding used by xml_parser_create(). Supported target encodings are `ISO-8859-1`, `US-ASCII` and `UTF-8`.

xml_set_character_data_handler

(PHP 3>= 3.0.6, PHP 4 )

xml_set_character_data_handler -- set up character data handler

Description

bool xml_set_character_data_handler ( resource parser, string handler)

Sets the character data handler function for the XML parser parser. handler is a string containing the name of a function that must exist when xml_parse() is called for parser.

The function named by handler must accept two parameters: handler ( resource parser, string data)

parser: The first parameter, parser, is a reference to the XML parser calling the handler.
data: The second parameter, data, contains the character data as a string.

If a handler function is set to an empty string, or FALSE, the handler in question is disabled.

TRUE is returned if the handler is set up, FALSE if parser is not a parser.

Poznámka: Místo názvu funkce může použito pole obsahující odkaz na objekt a název metody.

xml_set_default_handler

(PHP 3>= 3.0.6, PHP 4 )

xml_set_default_handler -- set up default handler

Description

bool xml_set_default_handler ( resource parser, string handler)

Sets the default handler function for the XML parser parser. handler is a string containing the name of a function that must exist when xml_parse() is called for parser.

The function named by handler must accept two parameters: handler ( resource parser, string data)

parser: The first parameter, parser, is a reference to the XML parser calling the handler.
data: The second parameter, data, contains the character data. This may be the XML declaration, document type declaration, entities or other data for which no other handler exists.

If a handler function is set to an empty string, or FALSE, the handler in question is disabled.

TRUE is returned if the handler is set up, FALSE if parser is not a parser.

Poznámka: Místo názvu funkce může použito pole obsahující odkaz na objekt a název metody.

xml_set_element_handler

(PHP 3>= 3.0.6, PHP 4 )

xml_set_element_handler -- set up start and end element handlers

Description

bool xml_set_element_handler ( resource parser, string start_element_handler, string end_element_handler)

Sets the element handler functions for the XML parser parser. start_element_handler and end_element_handler are strings containing the names of functions that must exist when xml_parse() is called for parser.

The function named by start_element_handler must accept three parameters: start_element_handler ( resource parser, string name, array attribs)

parser

The first parameter, parser, is a reference to the XML parser calling the handler.

name

The second parameter, name, contains the name of the element for which this handler is called. If case-folding is in effect for this parser, the element name will be in uppercase letters.

attribs

The third parameter, attribs, contains an associative array with the element's attributes (if any). The keys of this array are the attribute names, the values are the attribute values. Attribute names are case-folded on the same criteria as element names. Attribute values are not case-folded.

The original order of the attributes can be retrieved by walking through attribs the normal way, using each(). The first key in the array was the first attribute, and so on.

The function named by end_element_handler must accept two parameters: end_element_handler ( resource parser, string name)

parser: The first parameter, parser, is a reference to the XML parser calling the handler.
name: The second parameter, name, contains the name of the element for which this handler is called. If case-folding is in effect for this parser, the element name will be in uppercase letters.

If a handler function is set to an empty string, or FALSE, the handler in question is disabled.

TRUE is returned if the handlers are set up, FALSE if parser is not a parser.

Poznámka: Místo názvu funkce může použito pole obsahující odkaz na objekt a název metody.

xml_set_end_namespace_decl_handler

(PHP 4 >= 4.0.5)

xml_set_end_namespace_decl_handler -- Set up character data handler

Description

bool xml_set_end_namespace_decl_handler ( resource pind, string hdl)

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

Poznámka: Místo názvu funkce může použito pole obsahující odkaz na objekt a název metody.

xml_set_external_entity_ref_handler

(PHP 3>= 3.0.6, PHP 4 )

xml_set_external_entity_ref_handler -- set up external entity reference handler

Description

bool xml_set_external_entity_ref_handler ( resource parser, string handler)

Sets the external entity reference handler function for the XML parser parser. handler is a string containing the name of a function that must exist when xml_parse() is called for parser.

The function named by handler must accept five parameters, and should return an integer value. If the value returned from the handler is FALSE (which it will be if no value is returned), the XML parser will stop parsing and xml_get_error_code() will return XML_ERROR_EXTERNAL_ENTITY_HANDLING. handler ( resource parser, string open_entity_names, string base, string system_id, string public_id)

parser: The first parameter, parser, is a reference to the XML parser calling the handler.
open_entity_names: The second parameter, open_entity_names, is a space-separated list of the names of the entities that are open for the parse of this entity (including the name of the referenced entity).
base: This is the base for resolving the system identifier (system_id) of the external entity. Currently this parameter will always be set to an empty string.
system_id: The fourth parameter, system_id, is the system identifier as specified in the entity declaration.
public_id: The fifth parameter, public_id, is the public identifier as specified in the entity declaration, or an empty string if none was specified; the whitespace in the public identifier will have been normalized as required by the XML spec.

If a handler function is set to an empty string, or FALSE, the handler in question is disabled.

TRUE is returned if the handler is set up, FALSE if parser is not a parser.

Poznámka: Místo názvu funkce může použito pole obsahující odkaz na objekt a název metody.

xml_set_notation_decl_handler

(PHP 3>= 3.0.6, PHP 4 )

xml_set_notation_decl_handler -- set up notation declaration handler

Description

bool xml_set_notation_decl_handler ( resource parser, string handler)

Sets the notation declaration handler function for the XML parser parser. handler is a string containing the name of a function that must exist when xml_parse() is called for parser.

A notation declaration is part of the document's DTD and has the following format:

<!NOTATION name {system_id | public_id}>
See section 4.7 of the XML 1.0 spec for the definition of notation declarations.

The function named by handler must accept five parameters: handler ( resource parser, string notation_name, string base, string system_id, string public_id)

parser: The first parameter, parser, is a reference to the XML parser calling the handler.
notation_name: This is the notation's name, as per the notation format described above.
base: This is the base for resolving the system identifier (system_id) of the notation declaration. Currently this parameter will always be set to an empty string.
system_id: System identifier of the external notation declaration.
public_id: Public identifier of the external notation declaration.

If a handler function is set to an empty string, or FALSE, the handler in question is disabled.

TRUE is returned if the handler is set up, FALSE if parser is not a parser.

Poznámka: Místo názvu funkce může použito pole obsahující odkaz na objekt a název metody.

xml_set_object

(PHP 4 )

xml_set_object -- Use XML Parser within an object

Description

void xml_set_object ( resource parser, object object)

This function allows to use parser inside object. All callback functions could be set with xml_set_element_handler() etc and assumed to be methods of object.

<?php
class xml  {
    var $parser;

    function xml()
    {
        $this->parser = xml_parser_create();

        xml_set_object($this->parser, &$this);
        xml_set_element_handler($this->parser, "tag_open", "tag_close");
        xml_set_character_data_handler($this->parser, "cdata");
    }

    function parse($data)
    { 
        xml_parse($this->parser, $data);
    }

    function tag_open($parser, $tag, $attributes)
    { 
        var_dump($parser, $tag, $attributes); 
    }

    function cdata($parser, $cdata)
    {
        var_dump($parser, $cdata);
    }

    function tag_close($parser, $tag)
    {
        var_dump($parser, $tag);
    }

} // end of class xml

$xml_parser = new xml();
$xml_parser->parse("<A ID='hallo'>PHP</A>");
?>

xml_set_processing_instruction_handler

(PHP 3>= 3.0.6, PHP 4 )

xml_set_processing_instruction_handler -- Set up processing instruction (PI) handler

Description

bool xml_set_processing_instruction_handler ( resource parser, string handler)

Sets the processing instruction (PI) handler function for the XML parser parser. handler is a string containing the name of a function that must exist when xml_parse() is called for parser.

A processing instruction has the following format:

<?
       target 
       data?>

You can put PHP code into such a tag, but be aware of one limitation: in an XML PI, the PI end tag (?>) can not be quoted, so this character sequence should not appear in the PHP code you embed with PIs in XML documents. If it does, the rest of the PHP code, as well as the "real" PI end tag, will be treated as character data.

The function named by handler must accept three parameters: handler ( resource parser, string target, string data)

parser: The first parameter, parser, is a reference to the XML parser calling the handler.
target: The second parameter, target, contains the PI target.
data: The third parameter, data, contains the PI data.

If a handler function is set to an empty string, or FALSE, the handler in question is disabled.

TRUE is returned if the handler is set up, FALSE if parser is not a parser.

Poznámka: Místo názvu funkce může použito pole obsahující odkaz na objekt a název metody.

xml_set_start_namespace_decl_handler

(PHP 4 >= 4.0.5)

xml_set_start_namespace_decl_handler -- Set up character data handler

Description

bool xml_set_start_namespace_decl_handler ( resource pind, string hdl)

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

Poznámka: Místo názvu funkce může použito pole obsahující odkaz na objekt a název metody.

xml_set_unparsed_entity_decl_handler

(PHP 3>= 3.0.6, PHP 4 )

xml_set_unparsed_entity_decl_handler -- Set up unparsed entity declaration handler

Description

bool xml_set_unparsed_entity_decl_handler ( resource parser, string handler)

Sets the unparsed entity declaration handler function for the XML parser parser. handler is a string containing the name of a function that must exist when xml_parse() is called for parser.

This handler will be called if the XML parser encounters an external entity declaration with an NDATA declaration, like the following:

<!ENTITY name {publicId | systemId} NDATA notationName>

See section 4.2.2 of the XML 1.0 spec for the definition of notation declared external entities.

The function named by handler must accept six parameters: handler ( resource parser, string entity_name, string base, string system_id, string public_id, string notation_name)

parser: The first parameter, parser, is a reference to the XML parser calling the handler.
entity_name: The name of the entity that is about to be defined.
base: This is the base for resolving the system identifier (systemId) of the external entity. Currently this parameter will always be set to an empty string.
system_id: System identifier for the external entity.
public_id: Public identifier for the external entity.
notation_name: Name of the notation of this entity (see xml_set_notation_decl_handler()).

If a handler function is set to an empty string, or FALSE, the handler in question is disabled.

TRUE is returned if the handler is set up, FALSE if parser is not a parser.

Poznámka: Místo názvu funkce může použito pole obsahující odkaz na objekt a název metody.

CVI. XML-RPC functions

Úvod

These functions can be used to write XML-RPC servers and clients. You can find more information about XML-RPC at http://www.xmlrpc.com/, and more documentation on this extension and it's functions at http://xmlrpc-epi.sourceforge.net/.

Varování

Požadavky

Tyto funkce jsou k dispozici jako součást standardního modulu, který je vždy dostupný.

Instalace

XML-RPC support in PHP is not enabled by default. You will need to use the --with-xmlrpc configuration option when compiling PHP to enable XML-RPC support. This extension is bundled into PHP as of 4.1.0.

Konfigurace běhu

Toto rozšíření nemá definováno žádné konfigurační direktivy.

Typy prostředků

Toto rezšíření nemá definován žádný typ prostředku (resource).

Předdefinované konstanty

Toto rozšíření nemá definovány žádné konstanty.

Obsah
xmlrpc_decode_request -- Decodes XML into native PHP types
xmlrpc_decode -- Decodes XML into native PHP types
xmlrpc_encode_request -- Generates XML for a method request
xmlrpc_encode -- Generates XML for a PHP value
xmlrpc_get_type -- Gets xmlrpc type for a PHP value. Especially useful for base64 and datetime strings
xmlrpc_parse_method_descriptions -- Decodes XML into a list of method descriptions
xmlrpc_server_add_introspection_data -- Adds introspection documentation
xmlrpc_server_call_method -- Parses XML requests and call methods
xmlrpc_server_create -- Creates an xmlrpc server
xmlrpc_server_destroy -- Destroys server resources
xmlrpc_server_register_introspection_callback -- Register a PHP function to generate documentation
xmlrpc_server_register_method -- Register a PHP function to resource method matching method_name
xmlrpc_set_type -- Sets xmlrpc type, base64 or datetime, for a PHP string value

CVII. XSLT funkce

Varování

Úvod

O XSLT and Sablotronu

void xslt_set_log ( resource xh, mixed log)

xh: A reference to the XSLT parser.
log: This parameter is either a boolean value which toggles logging on and off, or a string containing the logfile in which log errors too.

This function allows you to set the file in which you want XSLT log messages to, XSLT log messages are different than error messages, in that log messages are not actually error messages but rather messages related to the state of the XSLT processor. They are useful for debugging XSLT, when something goes wrong.

By default logging is disabled, in order to enable logging you must first call xslt_set_log() with a boolean parameter which enables logging, then if you want to set the log file to debug to, you must then pass it a string containing the filename:

Příklad 1. Using the XSLT Logging features

<?php $xh = xslt_create(); xslt_set_log($xh, true); xslt_set_log($xh, getcwd() . 'myfile.log'); $result = xslt_process($xh, 'dog.xml', 'pets.xsl'); print($result); xslt_free($xh); ?>

xslt_set_sax_handler

(4.0.3 - 4.0.6 only)

xslt_set_sax_handler -- Určit SAX handlery XSLT procesoru

Popis

Varování

Tato funkce ještě není zdokumentována, k dispozici je pouze seznam argumentů.

CVIII. YAZ functions

Úvod

This extension offers a PHP interface to the YAZ toolkit that implements the Z39.50 protocol for information retrieval. With this extension you can easily implement a Z39.50 origin (client) that searches or scans Z39.50 targets (servers) in parallel.

The module hides most of the complexity of Z39.50 so it should be fairly easy to use. It supports persistent stateless connections very similar to those offered by the various SQL APIs that are available for PHP. This means that sessions are stateless but shared amongst users, thus saving the connect and initialize phase steps in most cases.

YAZ is available at http://www.indexdata.dk/yaz/. You can find news information, example scripts, etc. for this extension at http://www.indexdata.dk/phpyaz/.

Instalace

Compile YAZ and install it. Build PHP with your favourite modules and add option --with-yaz. Your task is roughly the following:

gunzip -c yaz-1.6.tar.gz|tar xf -
gunzip -c php-4.0.X.tar.gz|tar xf -
cd yaz-1.6
./configure --prefix=/usr
make
make install
cd ../php-4.0.X
./configure --with-yaz=/usr/bin
make
make install

Konfigurace běhu

Toto rozšíření nemá definováno žádné konfigurační direktivy.

Typy prostředků

Toto rezšíření nemá definován žádný typ prostředku (resource).

Předdefinované konstanty

Toto rozšíření nemá definovány žádné konstanty.

Příklady

PHP/YAZ keeps track of connections with targets (Z-Associations). A positive integer represents the ID of a particular association.

Příklad 1. Parallel searching using YAZ()

The script below demonstrates the parallel searching feature of the API. When invoked with no arguments it prints a query form; else (arguments are supplied) it searches the targets as given in in array host.

$num_hosts = count ($host); if (empty($term) || count($host) == 0) { echo '<form method="get"> <input type="checkbox" name="host[]" value="bagel.indexdata.dk/gils"> GILS test <input type="checkbox" name="host[]" value="localhost:9999/Default"> local test <input type="checkbox" checked="1" name="host[]" value="z3950.bell-labs.com/books"> BELL Labs Library <br> RPN Query: <input type="text" size="30" name="term"> <input type="submit" name="action" value="Search"> '; } else { echo 'You searced for ' . htmlspecialchars($term) . '<br>'; for ($i = 0; $i < $num_hosts; $i++) { $id[] = yaz_connect($host[$i]); yaz_syntax($id[$i],"sutrs"); yaz_search($id[$i],"rpn",$term); } yaz_wait(); for ($i = 0; $i < $num_hosts; $i++) { echo '<hr>' . $host[$i] . ":"; $error = yaz_error($id[$i]); if (!empty($error)) { echo "Error: $error"; } else { $hits = yaz_hits($id[$i]); echo "Result Count $hits"; } echo '<dl>'; for ($p = 1; $p <= 10; $p++) { $rec = yaz_record($id[$i],$p,"string"); if (empty($rec)) continue; echo "<dt><b>$p</b></dt><dd>"; echo ereg_replace("\n", "<br>\n",$rec); echo "</dd>"; } echo '</dl>'; } }

Obsah
yaz_addinfo -- Returns additional error information
yaz_ccl_conf -- Configure CCL parser
yaz_ccl_parse -- Invoke CCL Parser
yaz_close -- Closes a YAZ connection
yaz_connect -- Prepares for a connection and Z-association to a Z39.50 target.
yaz_database -- Specifies the databases within a session
yaz_element -- Specifies Element-Set Name for retrieval
yaz_errno -- Returns error number
yaz_error -- Returns error description
yaz_hits -- Returns number of hits for last search
yaz_itemorder -- Prepares for Z39.50 Item Order with an ILL-Request package
yaz_present -- Prepares for retrieval (Z39.50 present).
yaz_range -- Specifies the maximum number of records to retrieve
yaz_record -- Returns a record
yaz_scan_result -- Returns Scan Response result
yaz_scan -- Prepares for a scan
yaz_search -- Prepares for a search
yaz_sort -- Sets sorting criteria
yaz_syntax -- Specifies the preferred record syntax for retrieval.
yaz_wait -- Wait for Z39.50 requests to complete

yaz_addinfo

(PHP 4 >= 4.0.1)

yaz_addinfo -- Returns additional error information

Description

int yaz_addinfo ( int id)

Returns additional error message for target (last request). An empty string is returned if last operation was a success or if no additional information was provided by the target.

yaz_ccl_conf

(PHP 4 >= 4.0.5)

yaz_ccl_conf -- Configure CCL parser

Description

int yaz_ccl_conf ( int id, array config)

int yaz_connect ( string zurl [, mixed options])

This function returns a positive ID on success; zero on failure.

yaz_connect() prepares for a connection to a Z39.50 target. The zurl argument takes the form host[:port][/database]. If port is omitted 210 is used. If database is omitted Default is used. This function is non-blocking and doesn't attempt to establish a socket - it merely prepares a connect to be performed later when yaz_wait() is called.

If the second argument, options, is given as a string it is treated as the Z39.50 V2 authentication string (OpenAuth).

If options is given as an array the contents of the array serves as options. Note that array options are only supported for PHP 4.1.0 and later.

yaz_connect() options

user: Username for authentication.
group: Group for authentication.
password: Password for authentication.
cookie: Cookie for session (YAZ proxy).
proxy: Proxy for connection (YAZ proxy).
persistent: A boolean. If TRUE the connection is persistent; If FALSE the connection is not persistent. By default connections are persistent.
piggyback: A boolean. If TRUE piggyback is enabled for searches; If FALSE piggyback is disabled. By default piggyback is enabled. Enabling piggyback is more efficient and usually saves a network-round-trip for first time fetches of records. However, a few Z39.50 targets doesn't support piggyback or they ignore element set names. For those, piggyback should be disabled.

yaz_database

(PHP 4 >= 4.0.6)

yaz_database -- Specifies the databases within a session

Description

int yaz_database ( int id, string databases)

int yaz_hits ( int id)

yaz_hits() returns number of hits for last search.

yaz_itemorder

(PHP 4 >= 4.0.5)

yaz_itemorder -- Prepares for Z39.50 Item Order with an ILL-Request package

Description

int yaz_itemorder ( array args)

This function prepares for an Extended Services request using the Profile for the Use of Z39.50 Item Order Extended Service to Transport ILL (Profile/1). See this and the specification. The args parameter must be a hash array with information about the Item Order request to be sent. The key of the hash is the name of the corresponding ASN.1 tag path. For example, the ISBN below the Item-ID has the key item-id,ISBN.

The ILL-Request parameters are:

protocol-version-num
transaction-id,initial-requester-id,person-or-institution-symbol,person
transaction-id,initial-requester-id,person-or-institution-symbol,institution
transaction-id,initial-requester-id,name-of-person-or-institution,name-of-person
transaction-id,initial-requester-id,name-of-person-or-institution,name-of-institution
transaction-id,transaction-group-qualifier
transaction-id,transaction-qualifier
transaction-id,sub-transaction-qualifier
service-date-time,this,date
service-date-time,this,time
service-date-time,original,date
service-date-time,original,time
requester-id,person-or-institution-symbol,person
requester-id,person-or-institution-symbol,institution
requester-id,name-of-person-or-institution,name-of-person
requester-id,name-of-person-or-institution,name-of-institution
responder-id,person-or-institution-symbol,person
responder-id,person-or-institution-symbol,institution
responder-id,name-of-person-or-institution,name-of-person
responder-id,name-of-person-or-institution,name-of-institution
transaction-type
delivery-address,postal-address,name-of-person-or-institution,name-of-person
delivery-address,postal-address,name-of-person-or-institution,name-of-institution
delivery-address,postal-address,extended-postal-delivery-address
delivery-address,postal-address,street-and-number
delivery-address,postal-address,post-office-box
delivery-address,postal-address,city
delivery-address,postal-address,region
delivery-address,postal-address,country
delivery-address,postal-address,postal-code
delivery-address,electronic-address,telecom-service-identifier
delivery-address,electronic-address,telecom-service-addreess
billing-address,postal-address,name-of-person-or-institution,name-of-person
billing-address,postal-address,name-of-person-or-institution,name-of-institution
billing-address,postal-address,extended-postal-delivery-address
billing-address,postal-address,street-and-number
billing-address,postal-address,post-office-box
billing-address,postal-address,city
billing-address,postal-address,region
billing-address,postal-address,country
billing-address,postal-address,postal-code
billing-address,electronic-address,telecom-service-identifier
billing-address,electronic-address,telecom-service-addreess
ill-service-type
requester-optional-messages,can-send-RECEIVED
requester-optional-messages,can-send-RETURNED
requester-optional-messages,requester-SHIPPED
requester-optional-messages,requester-CHECKED-IN
search-type,level-of-service
search-type,need-before-date
search-type,expiry-date
search-type,expiry-flag
place-on-hold
client-id,client-name
client-id,client-status
client-id,client-identifier
item-id,item-type
item-id,call-number
item-id,author
item-id,title
item-id,sub-title
item-id,sponsoring-body
item-id,place-of-publication
item-id,publisher
item-id,series-title-number
item-id,volume-issue
item-id,edition
item-id,publication-date
item-id,publication-date-of-component
item-id,author-of-article
item-id,title-of-article
item-id,pagination
item-id,ISBN
item-id,ISSN
item-id,additional-no-letters
item-id,verification-reference-source
copyright-complicance
retry-flag
forward-flag
requester-note
forward-note

There are also a few parameters that are part of the Extended Services Request package and the ItemOrder package:

package-name
user-id
contact-name
contact-phone
contact-email
itemorder-item

yaz_present

(PHP 4 >= 4.0.5)

yaz_present -- Prepares for retrieval (Z39.50 present).

array yaz_scan_result ( int id [, array & result])

Given a target ID this function returns and array with terms as received from the target in the last Scan Response. This function returns an array (0..n-1) where n is the number of terms returned. Each value is a pair where first item is term, second item is result-count. If the result is given it will be modified to hold additional information taken from the Scan Response: number (number of entries returned), stepsize (Step-size), position (position of term), status (Scan Status).

yaz_scan

(PHP 4 >= 4.0.5)

yaz_scan -- Prepares for a scan

Description

int yaz_scan ( int id, string type, string startterm [, array flags])

This function prepares for a Z39.50 Scan Request. Argument id specifies target ID. Starting term point for the scan is given by startterm. The form in which is the starting term is specified is given by type. Currently type rpn is supported. The optional flags specifies additional information to control the behaviour of the scan request. Three indexes are currently read from the flags: number (number of terms requested), position (preferred position of term) and stepSize (preferred step size). To actually tranfer the Scan Request to the target and receive the Scan Response, yaz_wait() must be called. Upon completion of yaz_wait() call yaz_error() and yaz_scan_result() to handle the response.

The syntax of startterm is similar to the RPN query as described in yaz_search(). The startterm consists of zero or more @attr-operator specifications, then followed by exactly one token.

Příklad 1. PHP function that scans titles

function scan_titles($id, $starterm) { yaz_scan($id,"rpn", "@attr 1=4 " . $starterm); yaz_wait(); $errno = yaz_errno($id); if ($errno == 0) { $ar = yaz_scan_result($id,&$options); echo 'Scan ok; '; $ar = yaz_scan_result($id, &$options); while(list($key,$val)=each($options)) { echo "$key = $val  "; } echo '<br><table><tr><td>'; while(list($key,list($k, $term, $tcount))=each($ar)) { if (empty($k)) continue; echo "<tr><td>$term</td><td>"; echo $tcount; echo "</td></tr>"; } echo '</table>'; } else { echo "Scan failed. Error: " . yaz_error($id) . "<br>"; } }

yaz_search

(PHP 4 >= 4.0.1)

yaz_search -- Prepares for a search

Description

int yaz_search ( int id, string type, string query)

yaz_search() prepares for a search on the target with given id. The type represents the query type - only "rpn" is supported now in which case the third argument specifies a Type-1 query (RPN). Like yaz_connect() this function is non-blocking and only prepares for a search to be executed later when yaz_wait() is called.

The RPN query

The RPN query is a textual represenation of the Type-1 query as defined by the Z39.50 standard. However, in the text representation as used by YAZ a prefix notation is used, that is the operater precedes the operands. The query string is a sequence of tokens where white space is ignored is ignored unless surrounded by double quotes. Tokens beginning with an at-character (@) are considered operators, otherwise they are treated as search terms.

Tabulka 1. RPN Operators

Syntax	Description
`@and query1 query2`	intersection of query1 and query2
`@or query1 query2`	union of query1 and query2
`@not query1 query2`	query1 and not query2
`@set name`	result set reference
`@attrset set query`	specifies attribute-set for query. This construction is only allowed once - in the beginning of the whole query
`@attr set type=value query`	applies attribute to query. The type and value are integers specifying the attribute-type and attribute-value respectively. The set, if given, specifies the attribute-set.

Příklad 1. Query Examples

Query

computer
matches documents where "computer" occur. No attributes are specified.

The Query

"donald knuth"
matches documents where "donald knuth" occur.

For the query

@attr 1=4 art
attribute type is 1 (Bib-1 use), attribute value is 4 Title), so this should match documents where art occur in the title.

Another more complex one:

@attrset gils @and @attr 1=4 art @attr 1=1003 "donald knuth"
The query as a whole uses the GILS attributeset. The query matches documents where art occur in the title and in which donald knuth occur in the author.

yaz_sort

(PHP 4 >= 4.1.0)

yaz_sort -- Sets sorting criteria

Description

int yaz_sort ( int id, string criteria)

This function sets sorting criteria and enables Z39.50 Sort. Use this function together with yaz_search() or yaz_present(). Using this function alone doesn't have any effect. If used in conjunction with yaz_search() a Z39.50 Sort will be sent after a search response has been received and before any records are retrieved with Z39.50 Present. The criteria takes the form

field1 flags1 field2 flags2 ...

where field1 specifies primary attributes for sort, field2 seconds, etc.. The field specifies either numerical attribute combinations consisting of type=value pairs separated by comma (e.g. 1=4,2=1) ; or the field may specify a plain string criteria (e.g. title. The flags is a sequnce of the following characters which may not be separated by any white space.

Sort Flags

a: Sort ascending
d: Sort descending
i: Case insensitive sorting
s: Case sensitive sorting

Příklad 1. Sort Criterias

To sort on Bib1 attribute title, case insensitive, and ascending you'd use the following sort criteria:

1=4 ia

If the secondary sorting criteria should be author, case sensitive and ascending you'd use:

1=4 ia 1=1003 sa

yaz_syntax

(PHP 4 >= 4.0.1)

yaz_syntax -- Specifies the preferred record syntax for retrieval.

Description

int yaz_syntax ( int id, string syntax)

The syntax is specified as an OID (Object Identifier) in a raw dot-notation (like 1.2.840.10003.5.10) or as one of the known registered record syntaxes (sutrs, usmarc, grs1, xml, etc.). This function is used in conjunction with yaz_search() and yaz_present() to specify the preferred record syntax for retrieval.

yaz_wait

(PHP 4 >= 4.0.1)

yaz_wait -- Wait for Z39.50 requests to complete

Description

int yaz_wait ( [ array options])

This function carries out networked (blocked) activity for outstanding requests which have been prepared by the functions yaz_connect(), yaz_search(), yaz_present(), yaz_scan() and yaz_itemorder(). yaz_wait() returns when all targets have either completed all requests or aborted (in case of errors).

If the options array is given that holds options that change the behaviour of yaz_wait().

timeout: Sets timeout in seconds. If a target hasn't responded within the timeout it is considered dead and yaz_wait() returns. The default value for timeout is 15 seconds.

CIX. Funkce pro práci s YP/NIS

NIS (dříve Yellow Pages) umožňuje síťovou správu důležitých administrativních souborů (např. soubory s hesly). Více informací viz NIS man stránka a Introduction to YP/NIS. Existuje také kniha Managing NFS and NIS od Hala Sterna.

Pokud chcete tyto funkce zprovoznit, musíte PHP zkonfigurovat s --with-yp(PHP 3) nebo --enable-yp(PHP 4).

Obsah
yp_all -- Traverse the map and call a function on each entry
yp_cat -- Return an array containing the entire map
yp_err_string -- Returns the error string associated with the previous operation
yp_errno -- Returns the error code of the previous operation
yp_first -- Vrátit pvní klíč/hodnota pár mapy
yp_get_default_domain -- Zjistit defaultní NIS doménu stroje
yp_master -- Zjistit název master NIS serveru mapy
yp_match -- Vrátit odpovídající záznam
yp_next -- Vrátit další klíč/hodnota pár mapy
yp_order -- Returns the order number for a map

Viz také yp_errno().

yp_errno

(PHP 4 >= 4.0.6)

yp_errno -- Returns the error code of the previous operation

Popis

int yp_errno ( void)

yp_errno() returns the error code of the previous operation.

Possible errors are:

1 args to function are bad

2 RPC failure - domain has been unbound

3 can't bind to server on this domain

4 no such map in server's domain

5 no such key in map

6 internal yp server or client error

7 resource allocation failure

8 no more records in map database

9 can't communicate with portmapper

10 can't communicate with ypbind

11 can't communicate with ypserv

12 local domain name not set

13 yp database is bad

string yp_match ( string domain, string map, string key)

yp_match() vrací hodnotu asociovanou v dané mapě s předaným klíčem nebo FALSE. Klíč musí být dán přesně.

Příklad 1. Ukázka NIS match

<?php $entry = yp_match ($domain, "passwd.byname", "joe"); echo "Odpovídající záznam je: " . $entry; ?>

V tomto případě by to mohlo být: joe:##joe:11111:100:Joe User:/home/j/joe:/usr/local/bin/bash

Viz také yp-get-default-domain()

yp_next

(PHP 3>= 3.0.7, PHP 4 )

yp_next -- Vrátit další klíč/hodnota pár mapy

Popis

array yp_next ( string domain, string map, string key)

yp_next() vrací další klíč/hodnota pár v mapě po daném klíči, nebo FALSE.

Příklad 1. Ukázka NIS next

<?php $entry = yp_next ($domain, "passwd.byname", "joe"); if (!$entry) { echo yp_errno() . ": " . yp_err_string(); } $key = key ($entry); echo "Položka následující po joe má klíč " . $key . " a hodnotu " . $entry[$key]; ?>

Viz také yp-get-default-domain().

yp_order

(PHP 3>= 3.0.7, PHP 4 )

yp_order -- Returns the order number for a map

Popis

int yp_order ( string domain, string map)

yp_order() vrací pořadové číslo mapy nebo FALSE.

Příklad 1. Ukázka NIS order

<?php $number = yp_order($domain,$mapname); echo "Pořadové číslo této mapy je: " . $order; ?>

Viz také: yp-get-default-domain().

CX. Zip File Functions (Read Only Access)

Úvod

This module enables you to transparently read ZIP compressed archives and the files inside them.

Požadavky

This module uses the functions of the ZZIPlib library by Guido Draheim. You need ZZIPlib version >= 0.10.6.

Note that ZZIPlib only provides a subset of functions provided in a full implementation of the ZIP compression algorithm and can only read ZIP file archives. A normal ZIP utility is needed to create the ZIP file archives read by this library.

Instalace

Zip support in PHP is not enabled by default. You will need to use the --with-zip configuration option when compiling PHP to enable zip support.

Poznámka: Zip support before PHP 4.1.0 is experimental. This section reflects the Zip extension as it exists in PHP 4.1.0 and later.

Konfigurace běhu

Toto rozšíření nemá definováno žádné konfigurační direktivy.

Typy prostředků

Toto rezšíření nemá definován žádný typ prostředku (resource).

Předdefinované konstanty

Toto rozšíření nemá definovány žádné konstanty.

Příklady

This example opens a ZIP file archive, reads each file in the archive and prints out its contents. The test2.zip archive used in this example is one of the test archives in the ZZIPlib source distribution.

Příklad 1. Zip Usage Example

<?php

$zip = zip_open("/tmp/test2.zip");

if ($zip) {

    while ($zip_entry = zip_read($zip)) {
        echo "Name:               " . zip_entry_name($zip_entry) . "\n";
        echo "Actual Filesize:    " . zip_entry_filesize($zip_entry) . "\n";
        echo "Compressed Size:    " . zip_entry_compressedsize($zip_entry) . "\n";
        echo "Compression Method: " . zip_entry_compressionmethod($zip_entry) . "\n";

        if (zip_entry_open($zip, $zip_entry, "r")) {
            echo "File Contents:\n";
            $buf = zip_entry_read($zip_entry, zip_entry_filesize($zip_entry));
            echo "$buf\n";

            zip_entry_close($zip_entry);
        }
        echo "\n";

    }

    zip_close($zip);

}

?>

Obsah
zip_close -- Close a Zip File Archive
zip_entry_close -- Close a Directory Entry
zip_entry_compressedsize -- Retrieve the Compressed Size of a Directory Entry
zip_entry_compressionmethod -- Retrieve the Compression Method of a Directory Entry
zip_entry_filesize -- Retrieve the Actual File Size of a Directory Entry
zip_entry_name -- Retrieve the Name of a Directory Entry
zip_entry_open -- Open a Directory Entry for Reading
zip_entry_read -- Read From an Open Directory Entry
zip_open -- Open a Zip File Archive
zip_read -- Read Next Entry in a Zip File Archive

zip_close

(PHP 4 >= 4.1.0)

zip_close -- Close a Zip File Archive

Description

void zip_close ( resource zip)

bool zip_entry_open ( resource zip, resource zip_entry [, string mode])

Opens a directory entry in a zip file for reading. The parameter zip is a valid resource handle returned by zip_open(). The parameter zip_entry is a directory entry resource returned by zip_read(). The optional parameter mode can be any of the modes specified in the documentaion for fopen().

Poznámka: Currently, mode is ignored and is always "rb". This is due to the fact that zip support in PHP is read only access. Please see fopen() for an explanation of various modes, including "rb".

Vrací TRUE při úspěchu, FALSE při selhání.

Poznámka: Unlike fopen() and other similar functions, the return value of zip_entry_open() only indicates the result of the operation and is not needed for reading or closing the directory entry.

zip_entry_read

(PHP 4 >= 4.1.0)

zip_entry_read -- Read From an Open Directory Entry

Description

string zip_entry_read ( resource zip_entry [, int length])

Reads up to length bytes from an open directory entry. If length is not specified, then zip_entry_read() will attempt to read 1024 bytes. The parameter zip_entry is a valid directory entry returned by zip_read().

Poznámka: The length parameter should be the uncompressed length you wish to read.

Returns the data read, or FALSE if the end of the file is reached.

zip_open

(PHP 4 >= 4.1.0)

zip_open -- Open a Zip File Archive

Description

resource zip_open ( string filename)

Opens a new zip archive for reading. The filename parameter is the filename of the zip archive to open.

Returns a resource handle for later use with zip_read() and zip_close() or returns FALSE if filename does not exist.

See also zip_read() and zip_close().

zip_read

(PHP 4 >= 4.1.0)

zip_read -- Read Next Entry in a Zip File Archive

Description

resource zip_read ( resource zip)

Reads the next entry in a zip file archive. The parameter zip must be a zip archive previously opened by zip_open().

Returns a directory entry resource for later use with the zip_entry_...() functions.

CXI. Zlib Compression Functions

Úvod

This module enables you to transparently read and write gzip (.gz) compressed files, through versions of most of the filesystem functions which work with gzip-compressed files (and uncompressed files, too, but not with sockets).

Poznámka: Version 4.0.4 introduced a fopen-wrapper for .gz-files, so that you can use a special 'zlib:' URL to access compressed files transparently using the normal f*() file access functions if you prepend the filename or path with a 'zlib:' prefix when calling fopen().

In version 4.3.0, this special prefix has been changed to 'zlib://' to prevent ambiguities with filenames containing ':'.

This feature requires a C runtime library that provides the fopencookie() function. To my current knowledge the GNU libc is the only library that provides this feature.

Požadavky

This module uses the functions of zlib by Jean-loup Gailly and Mark Adler. You have to use a zlib version >= 1.0.9 with this module.

Konfigurace běhu

Toto rozšíření nemá definováno žádné konfigurační direktivy.

Typy prostředků

Toto rezšíření nemá definován žádný typ prostředku (resource).

Předdefinované konstanty

Tyto konstanty jsou definovány tímto rozšířením a budou k dispozici pouze tehdy, bylo-li rozšíření zkompilováno společně s PHP nebo dynamicky zavedeno za běhu.

FORCE_GZIP (integer)
FORCE_DEFLATE (integer)

Příklady

This example opens a temporary file and writes a test string to it, then it prints out the content of this file twice.

Příklad 1. Small Zlib Example

<?php

$filename = tempnam ('/tmp', 'zlibtest').'.gz';
print "<html>\n<head></head>\n<body>\n<pre>\n";
$s = "Only a test, test, test, test, test, test, test, test!\n";

// open file for writing with maximum compression
$zp = gzopen($filename, "w9");

// write string to file
gzwrite($zp, $s);

// close file
gzclose($zp);

// open file for reading
$zp = gzopen($filename, "r");

// read 3 char
print gzread($zp, 3);

// output until end of the file and close it.
gzpassthru($zp);

print "\n";

// open file and print content (the 2nd time).
if (readgzfile($filename) != strlen($s)) {
        echo "Error with zlib functions!";
}
unlink($filename);
print "</pre>\n</h1></body>\n</html>\n";

?>

Obsah
gzclose -- Close an open gz-file pointer
gzcompress -- Compress a string
gzdeflate -- Deflate a string
gzencode -- Create a gzip compressed string
gzeof -- Test for end-of-file on a gz-file pointer
gzfile -- Read entire gz-file into an array
gzgetc -- Get character from gz-file pointer
gzgets -- Get line from file pointer
gzgetss -- Get line from gz-file pointer and strip HTML tags
gzinflate -- Inflate a deflated string
gzopen -- Open gz-file
gzpassthru -- Output all remaining data on a gz-file pointer
gzputs -- Write to a gz-file pointer
gzread -- Binary-safe gz-file read
gzrewind -- Rewind the position of a gz-file pointer
gzseek -- Seek on a gz-file pointer
gztell -- Tell gz-file pointer read/write position
gzuncompress -- Uncompress a deflated string
gzwrite -- Binary-safe gz-file write
readgzfile -- Output a gz-file

(PHP 4 >= 4.0.4)

gzencode -- Create a gzip compressed string

Description

string gzencode ( string data [, int level [, int encoding_mode]])

This function returns a compressed version of the input data compatible with the output of the gzip program, or FALSE if an error is encountered. The optional parameter level can be given as 0 for no compression up to 9 for maximum compression, if not given the default compression level will be the default compression level of the zlib library.

You can also give FORCE_GZIP (the default) or FORCE_DEFLATE as optional third paramter encoding_mode. If you use FORCE_DEFLATE, you get a standard zlib deflated string (inclusive zlib headers) after the gzip file header but without the trailing crc32 checksum.

Poznámka: level was added in PHP 4.2, before PHP 4.2 gzencode() only had the data and (optional) encoding_mode parameters..

The resulting data contains the appropriate headers and data structure to make a standard .gz file, e.g.:

Příklad 1. Creating a gzip file

<?php $data = implode("", file("bigfile.txt")); $gzdata = gzencode($data, 9); $fp = fopen("bigfile.txt.gz", "w"); fwrite($fp, $gzdata); fclose($fp); ?>

For more information on the GZIP file format, see the document: GZIP file format specification version 4.3 (RFC 1952).

gzeof

(PHP 3, PHP 4 )

gzeof -- Test for end-of-file on a gz-file pointer

string gzgets ( int zp, int length)

Returns a (uncompressed) string of up to length - 1 bytes read from the file pointed to by fp. Reading ends when length - 1 bytes have been read, on a newline, or on EOF (whichever comes first).

If an error occurs, returns FALSE.

The file pointer must be valid, and must point to a file successfully opened by gzopen().

See also gzopen(), gzgetc(), and fgets().

gzgetss

(PHP 3, PHP 4 )

gzgetss -- Get line from gz-file pointer and strip HTML tags

Description

string gzgetss ( int zp, int length [, string allowable_tags])

Identical to gzgets(), except that gzgetss() attempts to strip any HTML and PHP tags from the text it reads.

You can use the optional third parameter to specify tags which should not be stripped.

Poznámka: Allowable_tags was added in PHP 3.0.13, PHP4B3.

See also gzgets(), gzopen(), and strip_tags().

gzinflate

(PHP 4 >= 4.0.4)

gzinflate -- Inflate a deflated string

Description

string gzinflate ( string data [, int length])

This function takes data compressed by gzdeflate() and returns the original uncompressed data or FALSE on error. The function will return an error if the uncompressed data is more than 256 times the length of the compressed input data or more than the optional parameter length.

gzopen

(PHP 3, PHP 4 )

gzopen -- Open gz-file

Description

int gzopen ( string filename, string mode [, int use_include_path])

Opens a gzip (.gz) file for reading or writing. The mode parameter is as in fopen() ("rb" or "wb") but can also include a compression level ("wb9") or a strategy: 'f' for filtered data as in "wb6f", 'h' for Huffman only compression as in "wb1h". (See the description of deflateInit2 in zlib.h for more information about the strategy parameter.)

gzopen() can be used to read a file which is not in gzip format; in this case gzread() will directly read from the file without decompression.

gzopen() returns a file pointer to the file opened, after that, everything you read from this file descriptor will be transparently decompressed and what you write gets compressed.

If the open fails, the function returns FALSE.

You can use the optional third parameter and set it to "1", if you want to search for the file in the include_path, too.

Příklad 1. gzopen() Example

$fp = gzopen ("/tmp/file.gz", "r");

gzpassthru

(PHP 3, PHP 4 )

gzpassthru -- Output all remaining data on a gz-file pointer

Description

int gzpassthru ( int zp)

Reads to EOF on the given gz-file pointer and writes the (uncompressed) results to standard output.

If an error occurs, returns FALSE.

The file pointer must be valid, and must point to a file successfully opened by gzopen().

The gz-file is closed when gzpassthru() is done reading it (leaving zp useless).

gzputs

(PHP 3, PHP 4 )

gzputs -- Write to a gz-file pointer

Description

int gzputs ( int zp, string str [, int length])

gzputs() is an alias to gzwrite(), and is identical in every way.

gzread

(PHP 3, PHP 4 )

gzread -- Binary-safe gz-file read

Description

string gzread ( int zp, int length)

gzread() reads up to length bytes from the gz-file pointer referenced by zp. Reading stops when length (uncompressed) bytes have been read or EOF is reached, whichever comes first.

// get contents of a gz-file into a string
$filename = "/usr/local/something.txt.gz";
$zd = gzopen ($filename, "r");
$contents = gzread ($zd, 10000);
gzclose ($zd);

gzrewind

(PHP 3, PHP 4 )

gzrewind -- Rewind the position of a gz-file pointer

string gzuncompress ( string data [, int length])

This function takes data compressed by gzcompress() and returns the original uncompressed data or FALSE on error. The function will return an error if the uncompressed data is more than 256 times the length of the compressed input data or more than the optional parameter length.

gzwrite

(PHP 3, PHP 4 )

gzwrite -- Binary-safe gz-file write

Description

int gzwrite ( int zp, string string [, int length])

gzwrite() writes the contents of string to the gz-file stream pointed to by zp. If the length argument is given, writing will stop after length (uncompressed) bytes have been written or the end of string is reached, whichever comes first.

Note that if the length argument is given, then the magic_quotes_runtime configuration option will be ignored and no slashes will be stripped from string.

See also gzread(), gzopen(), and gzputs().

readgzfile

(PHP 3, PHP 4 )

readgzfile -- Output a gz-file

Description

int readgzfile ( string filename [, int use_include_path])

Reads a file, decompresses it and writes it to standard output.

readgzfile() can be used to read a file which is not in gzip format; in this case readgzfile() will directly read from the file without decompression.

Returns the number of (uncompressed) bytes read from the file. If an error occurs, FALSE is returned and unless the function was called as @readgzfile, an error message is printed.

The file filename will be opened from the filesystem and its contents written to standard output.

You can use the optional second parameter and set it to "1", if you want to search for the file in the include_path, too.

See also gzpassthru(), gzfile(), and gzopen().

V. Extending PHP 4.0

Hacking the Core of PHP

Those who know don't talk.

Those who talk don't know.

Sometimes, PHP "as is" simply isn't enough. Although these cases are rare for the average user, professional applications will soon lead PHP to the edge of its capabilities, in terms of either speed or functionality. New functionality cannot always be implemented natively due to language restrictions and inconveniences that arise when having to carry around a huge library of default code appended to every single script, so another method needs to be found for overcoming these eventual lacks in PHP.

As soon as this point is reached, it's time to touch the heart of PHP and take a look at its core, the C code that makes PHP go.

Obsah
26. Overview
27. Extension Possibilities
28. Source Layout
29. PHP's Automatic Build System
30. Creating Extensions
31. Using Extensions
32. Troubleshooting
33. Source Discussion
34. Accepting Arguments
35. Creating Variables
36. Duplicating Variable Contents: The Copy Constructor
37. Returning Values
38. Printing Information
39. Startup and Shutdown Functions
40. Calling User Functions
41. Initialization File Support
42. Where to Go from Here
43. Reference: Some Configuration Macros
44. API Macros

Hacking the Core of PHP

Kapitola 26. Overview

"Extending PHP" is easier said than done. PHP has evolved to a full-fledged tool consisting of a few megabytes of source code, and to hack a system like this quite a few things have to be learned and considered. When structuring this chapter, we finally decided on the "learn by doing" approach. This is not the most scientific and professional approach, but the method that's the most fun and gives the best end results. In the following sections, you'll learn quickly how to get the most basic extensions to work almost instantly. After that, you'll learn about Zend's advanced API functionality. The alternative would have been to try to impart the functionality, design, tips, tricks, etc. as a whole, all at once, thus giving a complete look at the big picture before doing anything practical. Although this is the "better" method, as no dirty hacks have to be made, it can be very frustrating as well as energy- and time-consuming, which is why we've decided on the direct approach.

Note that even though this chapter tries to impart as much knowledge as possible about the inner workings of PHP, it's impossible to really give a complete guide to extending PHP that works 100% of the time in all cases. PHP is such a huge and complex package that its inner workings can only be understood if you make yourself familiar with it by practicing, so we encourage you to work with the source.

What Is Zend? and What Is PHP?

The name Zend refers to the language engine, PHP's core. The term PHP refers to the complete system as it appears from the outside. This might sound a bit confusing at first, but it's not that complicated (see 26-1). To implement a Web script interpreter, you need three parts:

The interpreter part analyzes the input code, translates it, and executes it.
The functionality part implements the functionality of the language (its functions, etc.).
The interface part talks to the Web server, etc.

Zend takes part 1 completely and a bit of part 2; PHP takes parts 2 and 3. Together they form the complete PHP package. Zend itself really forms only the language core, implementing PHP at its very basics with some predefined functions. PHP contains all the modules that actually create the language's outstanding capabilities.

Obrázek 26-1. The internal structure of PHP.

The following sections discuss where PHP can be extended and how it's done.

Kapitola 27. Extension Possibilities

As shown in 26-1 above, PHP can be extended primarily at three points: external modules, built-in modules, and the Zend engine. The following sections discuss these options.

External Modules

External modules can be loaded at script runtime using the function dl(). This function loads a shared object from disk and makes its functionality available to the script to which it's being bound. After the script is terminated, the external module is discarded from memory. This method has both advantages and disadvantages, as described in the following table:

Advantages	Disadvantages
External modules don't require recompiling of PHP.	The shared objects need to be loaded every time a script is being executed (every hit), which is very slow.
The size of PHP remains small by "outsourcing" certain functionality.	External additional files clutter up the disk.
	Every script that wants to use an external module's functionality has to specifically include a call to dl(), or the `extension` tag in `php.ini` needs to be modified (which is not always a suitable solution).

To sum up, external modules are great for third-party products, small additions to PHP that are rarely used, or just for testing purposes. To develop additional functionality quickly, external modules provide the best results. For frequent usage, larger implementations, and complex code, the disadvantages outweigh the advantages.

Third parties might consider using the extension tag in php.ini to create additional external modules to PHP. These external modules are completely detached from the main package, which is a very handy feature in commercial environments. Commercial distributors can simply ship disks or archives containing only their additional modules, without the need to create fixed and solid PHP binaries that don't allow other modules to be bound to them.

Built-in Modules

Built-in modules are compiled directly into PHP and carried around with every PHP process; their functionality is instantly available to every script that's being run. Like external modules, built-in modules have advantages and disadvantages, as described in the following table:

Advantages	Disadvantages
No need to load the module specifically; the functionality is instantly available.	Changes to built-in modules require recompiling of PHP.
No external files clutter up the disk; everything resides in the PHP binary.	The PHP binary grows and consumes more memory.

Built-in modules are best when you have a solid library of functions that remains relatively unchanged, requires better than poor-to-average performance, or is used frequently by many scripts on your site. The need to recompile PHP is quickly compensated by the benefit in speed and ease of use. However, built-in modules are not ideal when rapid development of small additions is required.

The Zend Engine

Of course, extensions can also be implemented directly in the Zend engine. This strategy is good if you need a change in the language behavior or require special functions to be built directly into the language core. In general, however, modifications to the Zend engine should be avoided. Changes here result in incompatibilities with the rest of the world, and hardly anyone will ever adapt to specially patched Zend engines. Modifications can't be detached from the main PHP sources and are overridden with the next update using the "official" source repositories. Therefore, this method is generally considered bad practice and, due to its rarity, is not covered in this book.

Kapitola 28. Source Layout

Poznámka: Prior to working through the rest of this chapter, you should retrieve clean, unmodified source trees of your favorite Web server. We're working with Apache (available at http://www.apache.org/) and, of course, with PHP (available at http://www.php.net/ - does it need to be said?).

Make sure that you can compile a working PHP environment by yourself! We won't go into this issue here, however, as you should already have this most basic ability when studying this chapter.

Before we start discussing code issues, you should familiarize yourself with the source tree to be able to quickly navigate through PHP's files. This is a must-have ability to implement and debug extensions.

After extracting the PHP archive, you'll see a directory layout similar to that in 28-1.

Obrázek 28-1. Main directory layout of the PHP source tree.

The following table describes the contents of the major directories.

Directory	Contents
`php-4`	Main PHP source files and main header files; here you'll find all of PHP's API definitions, macros, etc. (important).
`ext`	Repository for dynamic and built-in modules; by default, these are the "official" PHP modules that have been integrated into the main source tree. In PHP 4.0, it's possible to compile these standard extensions as dynamic loadable modules (at least, those that support it).
`pear`	Directory for the PHP class repository. At the time of this writing, this is still in the design phase, but it's being tried to establish something similar to CPAN for Perl here.
`sapi`	Contains the code for the different server abstraction layers.
`TSRM`	Location of the "Thread Safe Resource Manager" (TSRM) for Zend and PHP.
`Zend`	Location of Zend's file; here you'll find all of Zend's API definitions, macros, etc. (important).

Discussing all the files included in the PHP package is beyond the scope of this chapter. However, you should take a close look at the following files:

php.h, located in the main PHP directory. This file contains most of PHP's macro and API definitions.
zend.h, located in the main Zend directory. This file contains most of Zend's macros and definitions.
zend_API.h, also located in the Zend directory, which defines Zend's API.

You should also follow some sub-inclusions from these files; for example, the ones relating to the Zend executor, the PHP initialization file support, and such. After reading these files, take the time to navigate around the package a little to see the interdependencies of all files and modules - how they relate to each other and especially how they make use of each other. This also helps you to adapt to the coding style in which PHP is authored. To extend PHP, you should quickly adapt to this style.

Extension Conventions

Zend is built using certain conventions; to avoid breaking its standards, you should follow the rules described in the following sections.

Macros

For almost every important task, Zend ships predefined macros that are extremely handy. The tables and figures in the following sections describe most of the basic functions, structures, and macros. The macro definitions can be found mainly in zend.h and zend_API.h. We suggest that you take a close look at these files after having studied this chapter. (Although you can go ahead and read them now, not everything will make sense to you yet.)

Memory Management

Resource management is a crucial issue, especially in server software. One of the most valuable resources is memory, and memory management should be handled with extreme care. Memory management has been partially abstracted in Zend, and you should stick to this abstraction for obvious reasons: Due to the abstraction, Zend gets full control over all memory allocations. Zend is able to determine whether a block is in use, automatically freeing unused blocks and blocks with lost references, and thus prevent memory leaks. The functions to be used are described in the following table:

Function	Description
emalloc()	Serves as replacement for malloc().
efree()	Serves as replacement for free().
estrdup()	Serves as replacement for strdup().
estrndup()	Serves as replacement for strndup(). Faster than estrdup() and binary-safe. This is the recommended function to use if you know the string length prior to duplicating it.
ecalloc()	Serves as replacement for calloc().
erealloc()	Serves as replacement for realloc().

emalloc(), estrdup(), estrndup(), ecalloc(), and erealloc() allocate internal memory; efree() frees these previously allocated blocks. Memory handled by the e*() functions is considered local to the current process and is discarded as soon as the script executed by this process is terminated.

Varování

To allocate resident memory that survives termination of the current script, you can use malloc() and free(). This should only be done with extreme care, however, and only in conjunction with demands of the Zend API; otherwise, you risk memory leaks.

Zend also features a thread-safe resource manager to provide better native support for multithreaded Web servers. This requires you to allocate local structures for all of your global variables to allow concurrent threads to be run. Because the thread-safe mode of Zend was not finished back when this was written, it is not yet extensively covered here.

Directory and File Functions

The following directory and file functions should be used in Zend modules. They behave exactly like their C counterparts, but provide virtual working directory support on the thread level.

Zend Function	Regular C Function
V_GETCWD()	getcwd()
V_FOPEN()	fopen()
V_OPEN()	open()
V_CHDIR()	chdir()
V_GETWD()	getwd()
V_CHDIR_FILE()	Takes a file path as an argument and changes the current working directory to that file's directory.
V_STAT()	stat()
V_LSTAT()	lstat()

String Handling

Strings are handled a bit differently by the Zend engine than other values such as integers, Booleans, etc., which don't require additional memory allocation for storing their values. If you want to return a string from a function, introduce a new string variable to the symbol table, or do something similar, you have to make sure that the memory the string will be occupying has previously been allocated, using the aforementioned e*() functions for allocation. (This might not make much sense to you yet; just keep it somewhere in your head for now - we'll get back to it shortly.)

Complex Types

Complex types such as arrays and objects require different treatment. Zend features a single API for these types - they're stored using hash tables.

Poznámka: To reduce complexity in the following source examples, we're only working with simple types such as integers at first. A discussion about creating more advanced types follows later in this chapter.

Kapitola 29. PHP's Automatic Build System

PHP 4 features an automatic build system that's very flexible. All modules reside in a subdirectory of the ext directory. In addition to its own sources, each module consists of an M4 file (for example, see http://www.gnu.org/manual/m4/html_mono/m4.html) for configuration and a Makefile.in file, which is responsible for compilation (the results of autoconf and automake; for example, see http://sourceware.cygnus.com/autoconf/autoconf.html and http://sourceware.cygnus.com/automake/automake.html).

Both files are generated automatically, along with .cvsignore, by a little shell script named ext_skel that resides in the ext directory. As argument it takes the name of the module that you want to create. The shell script then creates a directory of the same name, along with the appropriate config.m4 and Makefile.in files.

Step by step, the process looks like this:

root@dev:/usr/local/src/php4/ext > ./ext_skel my_module Creating directory Creating basic files: config.m4 Makefile.in .cvsignore [done]. To use your new extension, you will have to execute the following steps: $ cd .. $ ./buildconf $ ./configure # (your extension is automatically enabled) $ vi ext/my_module/my_module.c $ make Repeat the last two steps as often as necessary.
This instruction creates the aforementioned files. To include the new module in the automatic configuration and build process, you have to run buildconf, which regenerates the configure script by searching through the ext directory and including all found config.m4 files.

Finally, running configure parses all configuration options and generates a makefile based on those options and the options you specify in Makefile.in.

29-1shows the previously generated Makefile.in:

Příklad 29-1. The default Makefile.in.

# $Id: Extending_Zend_Build.xml,v 1.6 2002/03/25 08:13:46 hholzgra Exp $ 
LTLIBRARY_NAME        = libmy_module.la
LTLIBRARY_SOURCES     = my_module.c 
LTLIBRARY_SHARED_NAME = my_module.la include
$(top_srcdir)/build/dynlib.mk

There's not much to tell about this one: It contains the names of the input and output files. You could also specify build instructions for other files if your module is built from multiple source files.

The default config.m4 shown in 29-2'/> is a bit more complex:

Příklad 29-2. The default config.m4.

dnl $Id: Extending_Zend_Build.xml,v 1.6 2002/03/25 08:13:46 hholzgra Exp $ 
dnl config.m4 for extension my_module 
dnl don't forget to call PHP_EXTENSION(my_module) 
dnl If your extension references something external, use with:
PHP_ARG_WITH(my_module, for my_module support, 
dnl Make sure that the comment is aligned: 
    [  --with-my_module             Include my_module support]) 
dnl Otherwise use enable:
PHP_ARG_ENABLE(my_module, whether to enable my_module support, 
dnl Make sure that the comment is aligned: 
    [  --enable-my_module           Enable my_module support]) 
if test "$PHP_MY_MODULE" != "no"; then
dnl Action.. 
PHP_EXTENSION(my_module, $ext_shared)
fi

If you're unfamiliar with M4 files (now is certainly a good time to get familiar), this might be a bit confusing at first; but it's actually quite easy.

Note: Everything prefixed with dnl is treated as a comment and is not parsed.

The config.m4 file is responsible for parsing the command-line options passed to configure at configuration time. This means that it has to check for required external files and do similar configuration and setup tasks.

The default file creates two configuration directives in the configure script: --with-my_module and --enable-my_module. Use the first option when referring external files (such as the --with-apache directive that refers to the Apache directory). Use the second option when the user simply has to decide whether to enable your extension. Regardless of which option you use, you should uncomment the other, unnecessary one; that is, if you're using --enable-my_module, you should remove support for --with-my_module, and vice versa.

By default, the config.m4 file created by ext_skel accepts both directives and automatically enables your extension. Enabling the extension is done by using the PHP_EXTENSION macro. To change the default behavior to include your module into the PHP binary when desired by the user (by explicitly specifying --enable-my_module or --with-my_module), change the test for $PHP_MY_MODULE to == "yes":

if test "$PHP_MY_MODULE" == "yes"; then dnl Action.. PHP_EXTENSION(my_module, $ext_shared) fi
This would require you to use --enable-my_module each time when reconfiguring and recompiling PHP.

Note: Be sure to run buildconf every time you change config.m4!

We'll go into more details on the M4 macros available to your configuration scripts later in this chapter. For now, we'll simply use the default files. The sample sources on the CD-ROM all have working config.m4 files. To include them into the PHP build process, simply copy the source directories to your PHP ext directory, run buildconf, and then include the sample modules you want by using the appropriate --enable-* directives with configure.

Kapitola 30. Creating Extensions

We'll start with the creation of a very simple extension at first, which basically does nothing more than implement a function that returns the integer it receives as parameter. 30-1 shows the source.

Příklad 30-1. A simple extension.

/* include standard header */
#include "php.h"

/* declaration of functions to be exported */
ZEND_FUNCTION(first_module);

/* compiled function list so Zend knows what's in this module */
zend_function_entry firstmod_functions[] =
{
    ZEND_FE(first_module, NULL)
    {NULL, NULL, NULL}
};

/* compiled module information */
zend_module_entry firstmod_module_entry =
{
    STANDARD_MODULE_HEADER,
    "First Module",
    firstmod_functions,
    NULL, 
    NULL, 
    NULL, 
    NULL, 
    NULL,
    NO_VERSION_YET,
    STANDARD_MODULE_PROPERTIES
};

/* implement standard "stub" routine to introduce ourselves to Zend */
#if COMPILE_DL_FIRST_MODULE
ZEND_GET_MODULE(firstmod)
#endif

/* implement function that is meant to be made available to PHP */
ZEND_FUNCTION(first_module)
{
    long parameter;

    if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "l", &parameter) == FAILURE) {
        return;
    }

    RETURN_LONG(parameter);
}

This code contains a complete PHP module. We'll explain the source code in detail shortly, but first we'd like to discuss the build process. (This will allow the impatient to experiment before we dive into API discussions.)

Poznámka: The example source makes use of some features introduced with the Zend version used in PHP 4.1.0 and above, it won't compile with older PHP 4.0.x versions.

Compiling Modules

There are basically two ways to compile modules:

Use the provided "make" mechanism in the ext directory, which also allows building of dynamic loadable modules.
Compile the sources manually.

The first method should definitely be favored, since, as of PHP 4.0, this has been standardized into a sophisticated build process. The fact that it is so sophisticated is also its drawback, unfortunately - it's hard to understand at first. We'll provide a more detailed introduction to this later in the chapter, but first let's work with the default files.

The second method is good for those who (for some reason) don't have the full PHP source tree available, don't have access to all files, or just like to juggle with their keyboard. These cases should be extremely rare, but for the sake of completeness we'll also describe this method.

Compiling Using Make. To compile the sample sources using the standard mechanism, copy all their subdirectories to the ext directory of your PHP source tree. Then run buildconf, which will create an updated configure script containing appropriate options for the new extension. By default, all the sample sources are disabled, so you don't have to fear breaking your build process.

After you run buildconf, configure --help shows the following additional modules:

--enable-array_experiments   BOOK: Enables array experiments
  --enable-call_userland       BOOK: Enables userland module
  --enable-cross_conversion    BOOK: Enables cross-conversion module
  --enable-first_module        BOOK: Enables first module
  --enable-infoprint           BOOK: Enables infoprint module
  --enable-reference_test      BOOK: Enables reference test module
  --enable-resource_test       BOOK: Enables resource test module
  --enable-variable_creation   BOOK: Enables variable-creation module

The module shown earlier in 30-1 can be enabled with --enable-first_module or --enable-first_module=yes.

Compiling Manually. To compile your modules manually, you need the following commands:

Action	Command
Compiling	cc -fpic -DCOMPILE_DL=1 -I/usr/local/include -I. -I.. -I../Zend -c -o `<your_object_file>` `<your_c_file>`
Linking	cc -shared -L/usr/local/lib -rdynamic -o `<your_module_file>` `<your_object_file(s)>`

The command to compile the module simply instructs the compiler to generate position-independent code (-fpic shouldn't be omitted) and additionally defines the constant COMPILE_DL to tell the module code that it's compiled as a dynamically loadable module (the test module above checks for this; we'll discuss it shortly). After these options, it specifies a number of standard include paths that should be used as the minimal set to compile the source files.

Note: All include paths in the example are relative to the directory ext. If you're compiling from another directory, change the pathnames accordingly. Required items are the PHP directory, the Zend directory, and (if necessary), the directory in which your module resides.

The link command is also a plain vanilla command instructing linkage as a dynamic module.

You can include optimization options in the compilation command, although these have been omitted in this example (but some are included in the makefile template described in an earlier section).

Note: Compiling and linking manually as a static module into the PHP binary involves very long instructions and thus is not discussed here. (It's not very efficient to type all those commands.)

Kapitola 31. Using Extensions

Depending on the build process you selected, you should either end up with a new PHP binary to be linked into your Web server (or run as CGI), or with an .so (shared object) file. If you compiled the example file first_module.c as a shared object, your result file should be first_module.so. To use it, you first have to copy it to a place from which it's accessible to PHP. For a simple test procedure, you can copy it to your htdocs directory and try it with the source in 31-1. If you compiled it into the PHP binary, omit the call to dl(), as the module's functionality is instantly available to your scripts.

Varování

For security reasons, you should not put your dynamic modules into publicly accessible directories. Even though it can be done and it simplifies testing, you should put them into a separate directory in production environments.

Příklad 31-1. A test file for first_module.so.

<?php
    
// remove next comment if necessary
// dl("first_module.so"); 

$param = 2;
$return = first_module($param);

print("We sent '$param' and got '$return'");

?>

Calling this PHP file in your Web browser should give you the output shown in 31-1.

Obrázek 31-1. Output of first_module.php.

If required, the dynamic loadable module is loaded by calling the dl() function. This function looks for the specified shared object, loads it, and makes its functions available to PHP. The module exports the function first_module(), which accepts a single parameter, converts it to an integer, and returns the result of the conversion.

If you've gotten this far, congratulations! You just built your first extension to PHP.

Kapitola 32. Troubleshooting

Actually, not much troubleshooting can be done when compiling static or dynamic modules. The only problem that could arise is that the compiler will complain about missing definitions or something similar. In this case, make sure that all header files are available and that you specified their path correctly in the compilation command. To be sure that everything is located correctly, extract a clean PHP source tree and use the automatic build in the ext directory with the fresh files; this will guarantee a safe compilation environment. If this fails, try manual compilation.

PHP might also complain about missing functions in your module. (This shouldn't happen with the sample sources if you didn't modify them.) If the names of external functions you're trying to access from your module are misspelled, they'll remain as "unlinked symbols" in the symbol table. During dynamic loading and linkage by PHP, they won't resolve because of the typing errors - there are no corresponding symbols in the main binary. Look for incorrect declarations in your module file or incorrectly written external references. Note that this problem is specific to dynamic loadable modules; it doesn't occur with static modules. Errors in static modules show up at compile time.

Kapitola 33. Source Discussion

Now that you've got a safe build environment and you're able to include the modules into PHP files, it's time to discuss how everything works.

Module Structure

All PHP modules follow a common structure:

Header file inclusions (to include all required macros, API definitions, etc.)
C declaration of exported functions (required to declare the Zend function block)
Declaration of the Zend function block
Declaration of the Zend module block
Implementation of get_module()
Implementation of all exported functions

Header File Inclusions

The only header file you really have to include for your modules is php.h, located in the PHP directory. This file makes all macros and API definitions required to build new modules available to your code.

Tip: It's good practice to create a separate header file for your module that contains module-specific definitions. This header file should contain all the forward definitions for exported functions and include php.h. If you created your module using ext_skel you already have such a header file prepared.

Declaring Exported Functions

To declare functions that are to be exported (i.e., made available to PHP as new native functions), Zend provides a set of macros. A sample declaration looks like this:

ZEND_FUNCTION ( my_function );

ZEND_FUNCTION declares a new C function that complies with Zend's internal API. This means that the function is of type void and accepts INTERNAL_FUNCTION_PARAMETERS (another macro) as parameters. Additionally, it prefixes the function name with zif. The immediately expanded version of the above definitions would look like this:

void zif_my_function ( INTERNAL_FUNCTION_PARAMETERS );
Expanding INTERNAL_FUNCTION_PARAMETERS results in the following:

void zif_my_function( int ht , zval * return_value , zval * this_ptr , int return_value_used , zend_executor_globals * executor_globals );

Since the interpreter and executor core have been separated from the main PHP package, a second API defining macros and function sets has evolved: the Zend API. As the Zend API now handles quite a few of the responsibilities that previously belonged to PHP, a lot of PHP functions have been reduced to macros aliasing to calls into the Zend API. The recommended practice is to use the Zend API wherever possible, as the old API is only preserved for compatibility reasons. For example, the types zval and pval are identical. zval is Zend's definition; pval is PHP's definition (actually, pval is an alias for zval now). As the macro INTERNAL_FUNCTION_PARAMETERS is a Zend macro, the above declaration contains zval. When writing code, you should always use zval to conform to the new Zend API.

The parameter list of this declaration is very important; you should keep these parameters in mind (see 33-1 for descriptions).

Tabulka 33-1. Zend's Parameters to Functions Called from PHP

Parameter	Description
`ht`	The number of arguments passed to the Zend function. You should not touch this directly, but instead use ZEND_NUM_ARGS() to obtain the value.
`return_value`	This variable is used to pass any return values of your function back to PHP. Access to this variable is best done using the predefined macros. For a description of these see below.
`this_ptr`	Using this variable, you can gain access to the object in which your function is contained, if it's used within an object. Use the function getThis() to obtain this pointer.
`return_value_used`	This flag indicates whether an eventual return value from this function will actually be used by the calling script. `0` indicates that the return value is not used; `1` indicates that the caller expects a return value. Evaluation of this flag can be done to verify correct usage of the function as well as speed optimizations in case returning a value requires expensive operations (for an example, see how `array.c` makes use of this).
`executor_globals`	This variable points to global settings of the Zend engine. You'll find this useful when creating new variables, for example (more about this later). The executor globals can also be introduced to your function by using the macro `TSRMLS_FETCH()`.

Declaration of the Zend Function Block

Now that you have declared the functions to be exported, you also have to introduce them to Zend. Introducing the list of functions is done by using an array of zend_function_entry. This array consecutively contains all functions that are to be made available externally, with the function's name as it should appear in PHP and its name as defined in the C source. Internally, zend_function_entry is defined as shown in 33-1.

Příklad 33-1. Internal declaration of zend_function_entry.

typedef struct _zend_function_entry { char *fname; void (*handler)(INTERNAL_FUNCTION_PARAMETERS); unsigned char *func_arg_types; } zend_function_entry;

Entry Description

fname Denotes the function name as seen in PHP (for example, fopen, mysql_connect, or, in our example, first_module).

handler Pointer to the C function responsible for handling calls to this function. For example, see the standard macro INTERNAL_FUNCTION_PARAMETERS discussed earlier.

func_arg_types Allows you to mark certain parameters so that they're forced to be passed by reference. You usually should set this to NULL.

In the example above, the declaration looks like this:

zend_function_entry firstmod_functions[] = { ZEND_FE(first_module, NULL) {NULL, NULL, NULL} };
You can see that the last entry in the list always has to be {NULL, NULL, NULL}. This marker has to be set for Zend to know when the end of the list of exported functions is reached.

Poznámka: You cannot use the predefined macros for the end marker, as these would try to refer to a function named "NULL"!

The macro ZEND_FE (short for 'Zend Function Entry') simply expands to a structure entry in zend_function_entry. Note that these macros introduce a special naming scheme to your functions - your C functions will be prefixed with zif_, meaning that ZEND_FE(first_module) will refer to a C function zif_first_module(). If you want to mix macro usage with hand-coded entries (not a good practice), keep this in mind.

Tip: Compilation errors that refer to functions named zif_*() relate to functions defined with ZEND_FE.

33-2 shows a list of all the macros that you can use to define functions.

Tabulka 33-2. Macros for Defining Functions

Macro Name	Description
`ZEND_FE(name, arg_types)`	Defines a function entry of the name `name` in `zend_function_entry`. Requires a corresponding C function. `arg_types` needs to be set to `NULL`. This function uses automatic C function name generation by prefixing the PHP function name with `zif_`. For example, `ZEND_FE("first_module", NULL)` introduces a function first_module() to PHP and links it to the C function zif_first_module(). Use in conjunction with `ZEND_FUNCTION`.
`ZEND_NAMED_FE(php_name, name, arg_types)`	Defines a function that will be available to PHP by the name `php_name` and links it to the corresponding C function `name`. `arg_types` needs to be set to `NULL`. Use this function if you don't want the automatic name prefixing introduced by `ZEND_FE`. Use in conjunction with `ZEND_NAMED_FUNCTION`.
`ZEND_FALIAS(name, alias, arg_types)`	Defines an alias named `alias` for `name`. `arg_types` needs to be set to `NULL`. Doesn't require a corresponding C function; refers to the alias target instead.
`PHP_FE(name, arg_types)`	Old PHP API equivalent of `ZEND_FE`.
`PHP_NAMED_FE(runtime_name, name, arg_types)`	Old PHP API equivalent of `ZEND_NAMED_FE`.

Note: You can't use ZEND_FE in conjunction with PHP_FUNCTION, or PHP_FE in conjunction with ZEND_FUNCTION. However, it's perfectly legal to mix ZEND_FE and ZEND_FUNCTION with PHP_FE and PHP_FUNCTION when staying with the same macro set for each function to be declared. But mixing is not recommended; instead, you're advised to use the ZEND_* macros only.

Declaration of the Zend Module Block

This block is stored in the structure zend_module_entry and contains all necessary information to describe the contents of this module to Zend. You can see the internal definition of this module in 33-2.

Příklad 33-2. Internal declaration of zend_module_entry.

typedef struct _zend_module_entry zend_module_entry;
     
    struct _zend_module_entry {
    unsigned short size;
    unsigned int zend_api;
    unsigned char zend_debug;
    unsigned char zts;
    char *name;
    zend_function_entry *functions;
    int (*module_startup_func)(INIT_FUNC_ARGS);
    int (*module_shutdown_func)(SHUTDOWN_FUNC_ARGS);
    int (*request_startup_func)(INIT_FUNC_ARGS);
    int (*request_shutdown_func)(SHUTDOWN_FUNC_ARGS);
    void (*info_func)(ZEND_MODULE_INFO_FUNC_ARGS);
    char *version;
    int (*global_startup_func)(void);
    int (*global_shutdown_func)(void);

[ Rest of the structure is not interesting here ]

};

Entry	Description
`size`, `zend_api`, `zend_debug` and `zts`	Usually filled with the `"STANDARD_MODULE_HEADER"`, which fills these four members with the size of the whole zend_module_entry, the `ZEND_MODULE_API_NO`, whether it is a debug build or normal build (`ZEND_DEBUG`) and if ZTS is enabled (`USING_ZTS`).
`name`	Contains the module name (for example, `"File functions"`, `"Socket functions"`, `"Crypt"`, etc.). This name will show up in phpinfo(), in the section "Additional Modules."
`functions`	Points to the Zend function block, discussed in the preceding section.
`module_startup_func`	This function is called once upon module initialization and can be used to do one-time initialization steps (such as initial memory allocation, etc.). To indicate a failure during initialization, return `FAILURE`; otherwise, `SUCCESS`. To mark this field as unused, use `NULL`. To declare a function, use the macro `ZEND_MINIT`.
`module_shutdown_func`	This function is called once upon module shutdown and can be used to do one-time deinitialization steps (such as memory deallocation). This is the counterpart to module_startup_func(). To indicate a failure during deinitialization, return `FAILURE`; otherwise, `SUCCESS`. To mark this field as unused, use `NULL`. To declare a function, use the macro `ZEND_MSHUTDOWN`.
`request_startup_func`	This function is called once upon every page request and can be used to do one-time initialization steps that are required to process a request. To indicate a failure here, return `FAILURE`; otherwise, `SUCCESS`. Note: As dynamic loadable modules are loaded only on page requests, the request startup function is called right after the module startup function (both initialization events happen at the same time). To mark this field as unused, use `NULL`. To declare a function, use the macro `ZEND_RINIT`.
`request_shutdown_func`	This function is called once after every page request and works as counterpart to request_startup_func(). To indicate a failure here, return `FAILURE`; otherwise, `SUCCESS`. Note: As dynamic loadable modules are loaded only on page requests, the request shutdown function is immediately followed by a call to the module shutdown handler (both deinitialization events happen at the same time). To mark this field as unused, use `NULL`. To declare a function, use the macro `ZEND_RSHUTDOWN`.
`info_func`	When phpinfo() is called in a script, Zend cycles through all loaded modules and calls this function. Every module then has the chance to print its own "footprint" into the output page. Generally this is used to dump environmental or statistical information. To mark this field as unused, use `NULL`. To declare a function, use the macro `ZEND_MINFO`.
`version`	The version of the module. You can use `NO_VERSION_YET` if you don't want to give the module a version number yet, but we really recommend that you add a version string here. Such a version string can look like this (in chronological order): `"2.5-dev"`, `"2.5RC1"`, `"2.5"` or `"2.5pl3"`.
Remaining structure elements	These are used internally and can be prefilled by using the macro `STANDARD_MODULE_PROPERTIES_EX`. You should not assign any values to them. Use `STANDARD_MODULE_PROPERTIES_EX` only if you use global startup and shutdown functions; otherwise, use `STANDARD_MODULE_PROPERTIES` directly.

In our example, this structure is implemented as follows:

zend_module_entry firstmod_module_entry = { STANDARD_MODULE_HEADER, "First Module", firstmod_functions, NULL, NULL, NULL, NULL, NULL, NO_VERSION_YET, STANDARD_MODULE_PROPERTIES, };
This is basically the easiest and most minimal set of values you could ever use. The module name is set to First Module, then the function list is referenced, after which all startup and shutdown functions are marked as being unused.

For reference purposes, you can find a list of the macros involved in declared startup and shutdown functions in 33-3. These are not used in our basic example yet, but will be demonstrated later on. You should make use of these macros to declare your startup and shutdown functions, as these require special arguments to be passed (INIT_FUNC_ARGS and SHUTDOWN_FUNC_ARGS), which are automatically included into the function declaration when using the predefined macros. If you declare your functions manually and the PHP developers decide that a change in the argument list is necessary, you'll have to change your module sources to remain compatible.

Tabulka 33-3. Macros to Declare Startup and Shutdown Functions

Macro	Description
`ZEND_MINIT(module)`	Declares a function for module startup. The generated name will be `zend_minit_<module>` (for example, `zend_minit_first_module`). Use in conjunction with `ZEND_MINIT_FUNCTION`.
`ZEND_MSHUTDOWN(module)`	Declares a function for module shutdown. The generated name will be `zend_mshutdown_<module>` (for example, `zend_mshutdown_first_module`). Use in conjunction with `ZEND_MSHUTDOWN_FUNCTION`.
`ZEND_RINIT(module)`	Declares a function for request startup. The generated name will be `zend_rinit_<module>` (for example, `zend_rinit_first_module`). Use in conjunction with `ZEND_RINIT_FUNCTION`.
`ZEND_RSHUTDOWN(module)`	Declares a function for request shutdown. The generated name will be `zend_rshutdown_<module>` (for example, `zend_rshutdown_first_module`). Use in conjunction with `ZEND_RSHUTDOWN_FUNCTION`.
`ZEND_MINFO(module)`	Declares a function for printing module information, used when phpinfo() is called. The generated name will be `zend_info_<module>` (for example, `zend_info_first_module`). Use in conjunction with `ZEND_MINFO_FUNCTION`.

Creation of get_module()

This function is special to all dynamic loadable modules. Take a look at the creation via the ZEND_GET_MODULE macro first:

#if COMPILE_DL_FIRSTMOD
     ZEND_GET_MODULE(firstmod) 
#endif

The function implementation is surrounded by a conditional compilation statement. This is needed since the function get_module() is only required if your module is built as a dynamic extension. By specifying a definition of COMPILE_DL_FIRSTMOD in the compiler command (see above for a discussion of the compilation instructions required to build a dynamic extension), you can instruct your module whether you intend to build it as a dynamic extension or as a built-in module. If you want a built-in module, the implementation of get_module() is simply left out.

get_module() is called by Zend at load time of the module. You can think of it as being invoked by the dl() call in your script. Its purpose is to pass the module information block back to Zend in order to inform the engine about the module contents.

If you don't implement a get_module() function in your dynamic loadable module, Zend will compliment you with an error message when trying to access it.

Implementation of All Exported Functions

Implementing the exported functions is the final step. The example function in first_module looks like this:

ZEND_FUNCTION(first_module) { long parameter; if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "l", &parameter) == FAILURE) { return; } RETURN_LONG(parameter); }
The function declaration is done using ZEND_FUNCTION, which corresponds to ZEND_FE in the function entry table (discussed earlier).

After the declaration, code for checking and retrieving the function's arguments, argument conversion, and return value generation follows (more on this later).

Summary

That's it, basically - there's nothing more to implementing PHP modules. Built-in modules are structured similarly to dynamic modules, so, equipped with the information presented in the previous sections, you'll be able to fight the odds when encountering PHP module source files.

Now, in the following sections, read on about how to make use of PHP's internals to build powerful extensions.

Kapitola 34. Accepting Arguments

One of the most important issues for language extensions is accepting and dealing with data passed via arguments. Most extensions are built to deal with specific input data (or require parameters to perform their specific actions), and function arguments are the only real way to exchange data between the PHP level and the C level. Of course, there's also the possibility of exchanging data using predefined global values (which is also discussed later), but this should be avoided by all means, as it's extremely bad practice.

PHP doesn't make use of any formal function declarations; this is why call syntax is always completely dynamic and never checked for errors. Checking for correct call syntax is left to the user code. For example, it's possible to call a function using only one argument at one time and four arguments the next time - both invocations are syntactically absolutely correct.

Determining the Number of Arguments

Since PHP doesn't have formal function definitions with support for call syntax checking, and since PHP features variable arguments, sometimes you need to find out with how many arguments your function has been called. You can use the ZEND_NUM_ARGS macro in this case. In previous versions of PHP, this macro retrieved the number of arguments with which the function has been called based on the function's hash table entry, ht, which is passed in the INTERNAL_FUNCTION_PARAMETERS list. As ht itself now contains the number of arguments that have been passed to the function, ZEND_NUM_ARGS has been stripped down to a dummy macro (see its definition in zend_API.h). But it's still good practice to use it, to remain compatible with future changes in the call interface. Note: The old PHP equivalent of this macro is ARG_COUNT.

The following code checks for the correct number of arguments:

if(ZEND_NUM_ARGS() != 2) WRONG_PARAM_COUNT;
If the function is not called with two arguments, it exits with an error message. The code snippet above makes use of the tool macro WRONG_PARAM_COUNT, which can be used to generate a standard error message (see 34-1).

Obrázek 34-1. WRONG_PARAM_COUNT in action.

This macro prints a default error message and then returns to the caller. Its definition can also be found in zend_API.h and looks like this:

ZEND_API void wrong_param_count(void); #define WRONG_PARAM_COUNT { wrong_param_count(); return; }
As you can see, it calls an internal function named wrong_param_count() that's responsible for printing the warning. For details on generating customized error messages, see the later section "Printing Information."

Retrieving Arguments

New parameter parsing API: This chapter documents the new Zend parameter parsing API introduced by Andrei Zmievski. It was introduced in the development stage between PHP 4.0.6 and 4.1.0 .

Parsing parameters is a very common operation and it may get a bit tedious. It would also be nice to have standardized error checking and error messages. Since PHP 4.1.0, there is a way to do just that by using the new parameter parsing API. It greatly simplifies the process of receiving parameteres, but it has a drawback in that it can't be used for functions that expect variable number of parameters. But since the vast majority of functions do not fall into those categories, this parsing API is recommended as the new standard way.

The prototype for parameter parsing function looks like this:

int zend_parse_parameters(int num_args TSRMLS_DC, char *type_spec, ...);
The first argument to this function is supposed to be the number of actual parameters passed to your function, so ZEND_NUM_ARGS() can be used for that. The second parameter should always be TSRMLS_CC macro. The third argument is a string that specifies the number and types of arguments your function is expecting, similar to how printf format string specifies the number and format of the output values it should operate on. And finally the rest of the arguments are pointers to variables which should receive the values from the parameters.

zend_parse_parameters() also performs type conversions whenever possible, so that you always receive the data in the format you asked for. Any type of scalar can be converted to another one, but conversions between complex types (arrays, objects, and resources) and scalar types are not allowed.

If the parameters could be obtained successfully and there were no errors during type conversion, the function will return SUCCESS, otherwise it will return FAILURE. The function will output informative error messages, if the number of received parameters does not match the requested number, or if type conversion could not be performed.

Here are some sample error messages:

Warning - ini_get_all() requires at most 1 parameter, 2 given Warning - wddx_deserialize() expects parameter 1 to be string, array given
Of course each error message is accompanied by the filename and line number on which it occurs.

Here is the full list of type specifiers:

l - long
d - double
s - string (with possible null bytes) and its length
b - boolean
r - resource, stored in zval*
a - array, stored in zval*
o - object (of any class), stored in zval*
O - object (of class specified by class entry), stored in zval*
z - the actual zval*

The following characters also have a meaning in the specifier string:

| - indicates that the remaining parameters are optional. The storage variables corresponding to these parameters should be initialized to default values by the extension, since they will not be touched by the parsing function if the parameters are not passed.
/ - the parsing function will call SEPARATE_ZVAL_IF_NOT_REF() on the parameter it follows, to provide a copy of the parameter, unless it's a reference.
! - the parameter it follows can be of specified type or NULL (only applies to a, o, O, r, and z). If NULL value is passed by the user, the storage pointer will be set to NULL.

The best way to illustrate the usage of this function is through examples:

/* Gets a long, a string and its length, and a zval. */ long l; char *s; int s_len; zval *param; if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "lsz", &l, &s, &s_len, &param) == FAILURE) { return; } /* Gets an object of class specified by my_ce, and an optional double. */ zval *obj; double d = 0.5; if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "O|d", &obj, my_ce, &d) == FAILURE) { return; } /* Gets an object or null, and an array. If null is passed for object, obj will be set to NULL. */ zval *obj; zval *arr; if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "O!a", &obj, &arr) == FAILURE) { return; } /* Gets a separated array. */ zval *arr; if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "a/", &arr) == FAILURE) { return; } /* Get only the first three parameters (useful for varargs functions). */ zval *z; zend_bool b; zval *r; if (zend_parse_parameters(3, "zbr!", &z, &b, &r) == FAILURE) { return; }

Note that in the last example we pass 3 for the number of received parameters, instead of ZEND_NUM_ARGS(). What this lets us do is receive the least number of parameters if our function expects a variable number of them. Of course, if you want to operate on the rest of the parameters, you will have to use zend_get_parameters_array_ex() to obtain them.

The parsing function has an extended version that allows for an additional flags argument that controls its actions.

int zend_parse_parameters_ex(int flags, int num_args TSRMLS_DC, char *type_spec, ...);

The only flag you can pass currently is ZEND_PARSE_PARAMS_QUIET, which instructs the function to not output any error messages during its operation. This is useful for functions that expect several sets of completely different arguments, but you will have to output your own error messages.

For example, here is how you would get either a set of three longs or a string:

long l1, l2, l3; char *s; if (zend_parse_parameters_ex(ZEND_PARSE_PARAMS_QUIET, ZEND_NUM_ARGS() TSRMLS_CC, "lll", &l1, &l2, &l3) == SUCCESS) { /* manipulate longs */ } else if (zend_parse_parameters_ex(ZEND_PARSE_PARAMS_QUIET, ZEND_NUM_ARGS(), "s", &s, &s_len) == SUCCESS) { /* manipulate string */ } else { php_error(E_WARNING, "%s() takes either three long values or a string as argument", get_active_function_name(TSRMLS_C)); return; }

With all the abovementioned ways of receiving function parameters you should have a good handle on this process. For even more example, look through the source code for extensions that are shipped with PHP - they illustrate every conceivable situation.

Old way of retrieving arguments (deprecated)

Deprecated parameter parsing API: This API is deprecated and superseded by the new ZEND parameter parsing API.

After having checked the number of arguments, you need to get access to the arguments themselves. This is done with the help of zend_get_parameters_ex():

zval **parameter; if(zend_get_parameters_ex(1, &parameter) != SUCCESS) WRONG_PARAM_COUNT;
All arguments are stored in a zval container, which needs to be pointed to twice. The snippet above tries to retrieve one argument and make it available to us via the parameter pointer.

zend_get_parameters_ex() accepts at least two arguments. The first argument is the number of arguments to retrieve (which should match the number of arguments with which the function has been called; this is why it's important to check for correct call syntax). The second argument (and all following arguments) are pointers to pointers to pointers to zvals. (Confusing, isn't it?) All these pointers are required because Zend works internally with **zval; to adjust a local **zval in our function,zend_get_parameters_ex() requires a pointer to it.

The return value of zend_get_parameters_ex() can either be SUCCESS or FAILURE, indicating (unsurprisingly) success or failure of the argument processing. A failure is most likely related to an incorrect number of arguments being specified, in which case you should exit with WRONG_PARAM_COUNT.

To retrieve more than one argument, you can use a similar snippet:

zval **param1, **param2, **param3, **param4; if(zend_get_parameters_ex(4, &param1, &param2, &param3, &param4) != SUCCESS) WRONG_PARAM_COUNT;

zend_get_parameters_ex() only checks whether you're trying to retrieve too many parameters. If the function is called with five arguments, but you're only retrieving three of them with zend_get_parameters_ex(), you won't get an error but will get the first three parameters instead. Subsequent calls of zend_get_parameters_ex() won't retrieve the remaining arguments, but will get the same arguments again.

Dealing with a Variable Number of Arguments/Optional Parameters

If your function is meant to accept a variable number of arguments, the snippets just described are sometimes suboptimal solutions. You have to create a line calling zend_get_parameters_ex() for every possible number of arguments, which is often unsatisfying.

For this case, you can use the function zend_get_parameters_array_ex(), which accepts the number of parameters to retrieve and an array in which to store them:

zval **parameter_array[4]; /* get the number of arguments */ argument_count = ZEND_NUM_ARGS(); /* see if it satisfies our minimal request (2 arguments) */ /* and our maximal acceptance (4 arguments) */ if(argument_count < 2 || argument_count > 5) WRONG_PARAM_COUNT; /* argument count is correct, now retrieve arguments */ if(zend_get_parameters_array_ex(argument_count, parameter_array) != SUCCESS) WRONG_PARAM_COUNT;
First, the number of arguments is checked to make sure that it's in the accepted range. After that, zend_get_parameters_array_ex() is used to fill parameter_array with valid pointers to the argument values.

A very clever implementation of this can be found in the code handling PHP's fsockopen() located in ext/standard/fsock.c, as shown in 34-1. Don't worry if you don't know all the functions used in this source yet; we'll get to them shortly.

Příklad 34-1. PHP's implementation of variable arguments in fsockopen().

pval **args[5];
int *sock=emalloc(sizeof(int));
int *sockp;
int arg_count=ARG_COUNT(ht);
int socketd = -1;
unsigned char udp = 0;
struct timeval timeout = { 60, 0 };
unsigned short portno;
unsigned long conv;
char *key = NULL;
FLS_FETCH();

if (arg_count > 5 || arg_count < 2 || zend_get_parameters_array_ex(arg_count,args)==FAILURE) {
    CLOSE_SOCK(1);
    WRONG_PARAM_COUNT;
}

switch(arg_count) {
    case 5:
        convert_to_double_ex(args[4]);
        conv = (unsigned long) (Z_DVAL_P(args[4]) * 1000000.0);
        timeout.tv_sec = conv / 1000000;
        timeout.tv_usec = conv % 1000000;
        /* fall-through */
    case 4:
        if (!PZVAL_IS_REF(*args[3])) {
            php_error(E_WARNING,"error string argument to fsockopen not passed by reference");
        }
        pval_copy_constructor(*args[3]);
        ZVAL_EMPTY_STRING(*args[3]);
        /* fall-through */
    case 3:
        if (!PZVAL_IS_REF(*args[2])) {
            php_error(E_WARNING,"error argument to fsockopen not passed by reference");
            return;
        }
        ZVAL_LONG(*args[2], 0);
        break;
}

convert_to_string_ex(args[0]);
convert_to_long_ex(args[1]);
portno = (unsigned short) Z_LVAL_P(args[1]);

key = emalloc(Z_STRLEN_P(args[0]) + 10);

fsockopen() accepts two, three, four, or five parameters. After the obligatory variable declarations, the function checks for the correct range of arguments. Then it uses a fall-through mechanism in a switch() statement to deal with all arguments. The switch() statement starts with the maximum number of arguments being passed (five). After that, it automatically processes the case of four arguments being passed, then three, by omitting the otherwise obligatory break keyword in all stages. After having processed the last case, it exits the switch() statement and does the minimal argument processing needed if the function is invoked with only two arguments.

This multiple-stage type of processing, similar to a stairway, allows convenient processing of a variable number of arguments.

Accessing Arguments

To access arguments, it's necessary for each argument to have a clearly defined type. Again, PHP's extremely dynamic nature introduces some quirks. Because PHP never does any kind of type checking, it's possible for a caller to pass any kind of data to your functions, whether you want it or not. If you expect an integer, for example, the caller might pass an array, and vice versa - PHP simply won't notice.

To work around this, you have to use a set of API functions to force a type conversion on every argument that's being passed (see 34-1).

Note: All conversion functions expect a **zval as parameter.

Tabulka 34-1. Argument Conversion Functions

Function	Description
convert_to_boolean_ex()	Forces conversion to a Boolean type. Boolean values remain untouched. Longs, doubles, and strings containing `0` as well as NULL values will result in Boolean `0` (FALSE). Arrays and objects are converted based on the number of entries or properties, respectively, that they have. Empty arrays and objects are converted to FALSE; otherwise, to TRUE. All other values result in a Boolean `1` (TRUE).
convert_to_long_ex()	Forces conversion to a long, the default integer type. NULL values, Booleans, resources, and of course longs remain untouched. Doubles are truncated. Strings containing an integer are converted to their corresponding numeric representation, otherwise resulting in `0`. Arrays and objects are converted to `0` if empty, `1` otherwise.
convert_to_double_ex()	Forces conversion to a double, the default floating-point type. NULL values, Booleans, resources, longs, and of course doubles remain untouched. Strings containing a number are converted to their corresponding numeric representation, otherwise resulting in `0.0`. Arrays and objects are converted to `0.0` if empty, `1.0` otherwise.
convert_to_string_ex()	Forces conversion to a string. Strings remain untouched. NULL values are converted to an empty string. Booleans containing TRUE are converted to `"1"`, otherwise resulting in an empty string. Longs and doubles are converted to their corresponding string representation. Arrays are converted to the string `"Array"` and objects to the string `"Object"`.
`convert_to_array_ex(value)`	Forces conversion to an array. Arrays remain untouched. Objects are converted to an array by assigning all their properties to the array table. All property names are used as keys, property contents as values. NULL values are converted to an empty array. All other values are converted to an array that contains the specific source value in the element with the key `0`.
`convert_to_object_ex(value)`	Forces conversion to an object. Objects remain untouched. NULL values are converted to an empty object. Arrays are converted to objects by introducing their keys as properties into the objects and their values as corresponding property contents in the object. All other types result in an object with the property `scalar` , having the corresponding source value as content.
`convert_to_null_ex(value)`	Forces the type to become a NULL value, meaning empty.

Poznámka: You can find a demonstration of the behavior in cross_conversion.php on the accompanying CD-ROM. 34-2 shows the output.

Obrázek 34-2. Cross-conversion behavior of PHP.

Using these functions on your arguments will ensure type safety for all data that's passed to you. If the supplied type doesn't match the required type, PHP forces dummy contents on the resulting value (empty strings, arrays, or objects, 0 for numeric values, FALSE for Booleans) to ensure a defined state.

Following is a quote from the sample module discussed previously, which makes use of the conversion functions:

zval **parameter; if((ZEND_NUM_ARGS() != 1) || (zend_get_parameters_ex(1, &parameter) != SUCCESS)) { WRONG_PARAM_COUNT; } convert_to_long_ex(parameter); RETURN_LONG(Z_LVAL_P(parameter));
After retrieving the parameter pointer, the parameter value is converted to a long (an integer), which also forms the return value of this function. Understanding access to the contents of the value requires a short discussion of the zval type, whose definition is shown in 34-2.

Příklad 34-2. PHP/Zend zval type definition.

typedef pval zval;
     
typedef struct _zval_struct zval;

typedef union _zvalue_value {
	long lval;					/* long value */
	double dval;				/* double value */
	struct {
		char *val;
		int len;
	} str;
	HashTable *ht;				/* hash table value */
	struct {
		zend_class_entry *ce;
		HashTable *properties;
	} obj;
} zvalue_value;

struct _zval_struct {
	/* Variable information */
	zvalue_value value;		/* value */
	unsigned char type;	/* active type */
	unsigned char is_ref;
	short refcount;
};

Actually, pval (defined in php.h) is only an alias of zval (defined in zend.h), which in turn refers to _zval_struct. This is a most interesting structure. _zval_struct is the "master" structure, containing the value structure, type, and reference information. The substructure zvalue_value is a union that contains the variable's contents. Depending on the variable's type, you'll have to access different members of this union. For a description of both structures, see 34-2, 34-3 and 34-4.

Tabulka 34-2. Zend zval Structure

Entry	Description
`value`	Union containing this variable's contents. See 34-3 for a description.
`type`	Contains this variable's type. For a list of available types, see 34-4.
`is_ref`	0 means that this variable is not a reference; 1 means that this variable is a reference to another variable.
`refcount`	The number of references that exist for this variable. For every new reference to the value stored in this variable, this counter is increased by 1. For every lost reference, this counter is decreased by 1. When the reference counter reaches 0, no references exist to this value anymore, which causes automatic freeing of the value.

Tabulka 34-3. Zend zvalue_value Structure

Entry	Description
`lval`	Use this property if the variable is of the type `IS_LONG`, `IS_BOOLEAN`, or `IS_RESOURCE`.
`dval`	Use this property if the variable is of the type `IS_DOUBLE`.
`str`	This structure can be used to access variables of the type `IS_STRING`. The member `len` contains the string length; the member `val` points to the string itself. Zend uses C strings; thus, the string length contains a trailing `0x00`.
`ht`	This entry points to the variable's hash table entry if the variable is an array.
`obj`	Use this property if the variable is of the type `IS_OBJECT`.

Tabulka 34-4. Zend Variable Type Constants

Constant	Description
`IS_NULL`	Denotes a NULL (empty) value.
`IS_LONG`	A long (integer) value.
`IS_DOUBLE`	A double (floating point) value.
`IS_STRING`	A string.
`IS_ARRAY`	Denotes an array.
`IS_OBJECT`	An object.
`IS_BOOL`	A Boolean value.
`IS_RESOURCE`	A resource (for a discussion of resources, see the appropriate section below).
`IS_CONSTANT`	A constant (defined) value.

To access a long you access zval.value.lval, to access a double you use zval.value.dval, and so on. Because all values are stored in a union, trying to access data with incorrect union members results in meaningless output.

Accessing arrays and objects is a bit more complicated and is discussed later.

Dealing with Arguments Passed by Reference

If your function accepts arguments passed by reference that you intend to modify, you need to take some precautions.

What we didn't say yet is that under the circumstances presented so far, you don't have write access to any zval containers designating function parameters that have been passed to you. Of course, you can change any zval containers that you created within your function, but you mustn't change any zvals that refer to Zend-internal data!

We've only discussed the so-called *_ex() API so far. You may have noticed that the API functions we've used are called zend_get_parameters_ex() instead of zend_get_parameters(), convert_to_long_ex() instead of convert_to_long(), etc. The *_ex() functions form the so-called new "extended" Zend API. They give a minor speed increase over the old API, but as a tradeoff are only meant for providing read-only access.

Because Zend works internally with references, different variables may reference the same value. Write access to a zval container requires this container to contain an isolated value, meaning a value that's not referenced by any other containers. If a zval container were referenced by other containers and you changed the referenced zval, you would automatically change the contents of the other containers referencing this zval (because they'd simply point to the changed value and thus change their own value as well).

zend_get_parameters_ex() doesn't care about this situation, but simply returns a pointer to the desired zval containers, whether they consist of references or not. Its corresponding function in the traditional API, zend_get_parameters(), immediately checks for referenced values. If it finds a reference, it creates a new, isolated zval container; copies the referenced data into this newly allocated space; and then returns a pointer to the new, isolated value.

This action is called zval separation (or pval separation). Because the *_ex() API doesn't perform zval separation, it's considerably faster, while at the same time disabling write access.

To change parameters, however, write access is required. Zend deals with this situation in a special way: Whenever a parameter to a function is passed by reference, it performs automatic zval separation. This means that whenever you're calling a function like this in PHP, Zend will automatically ensure that $parameter is being passed as an isolated value, rendering it to a write-safe state:

my_function(&$parameter);

But this is not the case with regular parameters! All other parameters that are not passed by reference are in a read-only state.

This requires you to make sure that you're really working with a reference - otherwise you might produce unwanted results. To check for a parameter being passed by reference, you can use the macro PZVAL_IS_REF. This macro accepts a zval* to check if it is a reference or not. Examples are given in in 34-3.

Příklad 34-3. Testing for referenced parameter passing.

zval *parameter;

if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "z", &parameter) == FAILURE)
    return;

/* check for parameter being passed by reference */
if (!PZVAL_IS_REF(*parameter)) {
{
    zend_error(E_WARNING, "Parameter wasn't passed by reference");
    RETURN_NULL();
}

/* make changes to the parameter */
ZVAL_LONG(*parameter, 10);

Assuring Write Safety for Other Parameters

You might run into a situation in which you need write access to a parameter that's retrieved with zend_get_parameters_ex() but not passed by reference. For this case, you can use the macro SEPARATE_ZVAL, which does a zval separation on the provided container. The newly generated zval is detached from internal data and has only a local scope, meaning that it can be changed or destroyed without implying global changes in the script context:

zval **parameter; /* retrieve parameter */ zend_get_parameters_ex(1, &parameter); /* at this stage, <parameter> still is connected */ /* to Zend's internal data buffers */ /* make <parameter> write-safe */ SEPARATE_ZVAL(parameter); /* now we can safely modify <parameter> */ /* without implying global changes */
SEPARATE_ZVAL uses emalloc() to allocate the new zval container, which means that even if you don't deallocate this memory yourself, it will be destroyed automatically upon script termination. However, doing a lot of calls to this macro without freeing the resulting containers will clutter up your RAM.

Note: As you can easily work around the lack of write access in the "traditional" API (with zend_get_parameters() and so on), this API seems to be obsolete, and is not discussed further in this chapter.

Kapitola 35. Creating Variables

When exchanging data from your own extensions with PHP scripts, one of the most important issues is the creation of variables. This section shows you how to deal with the variable types that PHP supports.

Overview

To create new variables that can be seen "from the outside" by the executing script, you need to allocate a new zval container, fill this container with meaningful values, and then introduce it to Zend's internal symbol table. This basic process is common to all variable creations:

zval *new_variable; 

/* allocate and initialize new container */
MAKE_STD_ZVAL(new_variable); 

/* set type and variable contents here, see the following sections */ 

/* introduce this variable by the name "new_variable_name" into the symbol table */
ZEND_SET_SYMBOL(EG(active_symbol_table), "new_variable_name", new_variable); 

/* the variable is now accessible to the script by using $new_variable_name */

The macro MAKE_STD_ZVAL allocates a new zval container using ALLOC_ZVAL and initializes it using INIT_ZVAL. As implemented in Zend at the time of this writing, initializing means setting the reference count to 1 and clearing the is_ref flag, but this process could be extended later - this is why it's a good idea to keep using MAKE_STD_ZVAL instead of only using ALLOC_ZVAL. If you want to optimize for speed (and you don't have to explicitly initialize the zval container here), you can use ALLOC_ZVAL, but this isn't recommended because it doesn't ensure data integrity.

ZEND_SET_SYMBOL takes care of introducing the new variable to Zend's symbol table. This macro checks whether the value already exists in the symbol table and converts the new symbol to a reference if so (with automatic deallocation of the old zval container). This is the preferred method if speed is not a crucial issue and you'd like to keep memory usage low.

Note that ZEND_SET_SYMBOL makes use of the Zend executor globals via the macro EG. By specifying EG(active_symbol_table), you get access to the currently active symbol table, dealing with the active, local scope. The local scope may differ depending on whether the function was invoked from within a function.

If you need to optimize for speed and don't care about optimal memory usage, you can omit the check for an existing variable with the same value and instead force insertion into the symbol table by using zend_hash_update():

zval *new_variable; /* allocate and initialize new container */ MAKE_STD_ZVAL(new_variable); /* set type and variable contents here, see the following sections */ /* introduce this variable by the name "new_variable_name" into the symbol table */ zend_hash_update( EG(active_symbol_table), "new_variable_name", strlen("new_variable_name") + 1, &new_variable, sizeof(zval *), NULL );
This is actually the standard method used in most modules.

The variables generated with the snippet above will always be of local scope, so they reside in the context in which the function has been called. To create new variables in the global scope, use the same method but refer to another symbol table:

zval *new_variable; // allocate and initialize new container MAKE_STD_ZVAL(new_variable); // // set type and variable contents here // // introduce this variable by the name "new_variable_name" into the global symbol table ZEND_SET_SYMBOL(&EG(symbol_table), "new_variable_name", new_variable);
The macro ZEND_SET_SYMBOL is now being called with a reference to the main, global symbol table by referring EG(symbol_table).

Note: The active_symbol_table variable is a pointer, but symbol_table is not. This is why you have to use EG(active_symbol_table) and &EG(symbol_table) as parameters to ZEND_SET_SYMBOL - it requires a pointer.

Similarly, to get a more efficient version, you can hardcode the symbol table update:

zval *new_variable; // allocate and initialize new container MAKE_STD_ZVAL(new_variable); // // set type and variable contents here // // introduce this variable by the name "new_variable_name" into the global symbol table zend_hash_update( &EG(symbol_table), "new_variable_name", strlen("new_variable_name") + 1, &new_variable, sizeof(zval *), NULL );
35-1 shows a sample source that creates two variables - local_variable with a local scope and global_variable with a global scope (see Figure 9.7). The full example can be found on the CD-ROM.

Note: You can see that the global variable is actually not accessible from within the function. This is because it's not imported into the local scope using global $global_variable; in the PHP source.

Příklad 35-1. Creating variables with different scopes.

ZEND_FUNCTION(variable_creation)
{
    zval *new_var1, *new_var2;

    MAKE_STD_ZVAL(new_var1);
    MAKE_STD_ZVAL(new_var2);

    ZVAL_LONG(new_var1, 10);
    ZVAL_LONG(new_var2, 5);

    ZEND_SET_SYMBOL(EG(active_symbol_table), "local_variable", new_var1);
    ZEND_SET_SYMBOL(&EG(symbol_table), "global_variable", new_var2);

    RETURN_NULL();

}

Longs (Integers)

Now let's get to the assignment of data to variables, starting with longs. Longs are PHP's integers and are very simple to store. Looking at the zval.value container structure discussed earlier in this chapter, you can see that the long data type is directly contained in the union, namely in the lval field. The corresponding type value for longs is IS_LONG (see 35-2).

Příklad 35-2. Creation of a long.

zval *new_long; MAKE_STD_ZVAL(new_long); new_long->type = IS_LONG; new_long->value.lval = 10;
Alternatively, you can use the macro ZVAL_LONG:

zval *new_long; MAKE_STD_ZVAL(new_long); ZVAL_LONG(new_long, 10);

Doubles (Floats)

Doubles are PHP's floats and are as easy to assign as longs, because their value is also contained directly in the union. The member in the zval.value container is dval; the corresponding type is IS_DOUBLE.

zval *new_double; MAKE_STD_ZVAL(new_double); new_double->type = IS_DOUBLE; new_double->value.dval = 3.45;
Alternatively, you can use the macro ZVAL_DOUBLE:

zval *new_double; MAKE_STD_ZVAL(new_double); ZVAL_DOUBLE(new_double, 3.45);

Strings

Strings need slightly more effort. As mentioned earlier, all strings that will be associated with Zend's internal data structures need to be allocated using Zend's own memory-management functions. Referencing of static strings or strings allocated with standard routines is not allowed. To assign strings, you have to access the structure str in the zval.value container. The corresponding type is IS_STRING:

zval *new_string; char *string_contents = "This is a new string variable"; MAKE_STD_ZVAL(new_string); new_string->type = IS_STRING; new_string->value.str.len = strlen(string_contents); new_string->value.str.val = estrdup(string_contents);
Note the usage of Zend's estrdup() here. Of course, you can also use the predefined macro ZVAL_STRING:

zval *new_string; char *string_contents = "This is a new string variable"; MAKE_STD_ZVAL(new_string); ZVAL_STRING(new_string, string_contents, 1);
ZVAL_STRING accepts a third parameter that indicates whether the supplied string contents should be duplicated (using estrdup()). Setting this parameter to 1 causes the string to be duplicated; 0 simply uses the supplied pointer for the variable contents. This is most useful if you want to create a new variable referring to a string that's already allocated in Zend internal memory.

If you want to truncate the string at a certain position or you already know its length, you can use ZVAL_STRINGL(zval, string, length, duplicate), which accepts an explicit string length to be set for the new string. This macro is faster than ZVAL_STRING and also binary-safe.

To create empty strings, set the string length to 0 and use empty_string as contents:

new_string->type = IS_STRING; new_string->value.str.len = 0; new_string->value.str.val = empty_string;
Of course, there's a macro for this as well (ZVAL_EMPTY_STRING):

MAKE_STD_ZVAL(new_string); ZVAL_EMPTY_STRING(new_string);

Booleans

Booleans are created just like longs, but have the type IS_BOOL. Allowed values in lval are 0 and 1:

zval *new_bool; MAKE_STD_ZVAL(new_bool); new_bool->type = IS_BOOL; new_bool->value.lval = 1;
The corresponding macros for this type are ZVAL_BOOL (allowing specification of the value) as well as ZVAL_TRUE and ZVAL_FALSE (which explicitly set the value to TRUE and FALSE, respectively).

Arrays

Arrays are stored using Zend's internal hash tables, which can be accessed using the zend_hash_*() API. For every array that you want to create, you need a new hash table handle, which will be stored in the ht member of the zval.value container.

There's a whole API solely for the creation of arrays, which is extremely handy. To start a new array, you call array_init().

zval *new_array; MAKE_STD_ZVAL(new_array); if(array_init(new_array) != SUCCESS) { // do error handling here }
If array_init() fails to create a new array, it returns FAILURE.

To add new elements to the array, you can use numerous functions, depending on what you want to do. 35-1, 35-2 and 35-3 describe these functions. All functions return FAILURE on failure and SUCCESS on success.

Tabulka 35-1. Zend's API for Associative Arrays

Function	Description
*add_assoc_long(zval array, char key, long n);()*	Adds an element of type `long`.
*add_assoc_unset(zval array, char key);()*	Adds an unset element.
*add_assoc_bool(zval array, char key, int b);()*	Adds a Boolean element.
*add_assoc_resource(zval array, char key, int r);()*	Adds a resource to the array.
*add_assoc_double(zval array, char key, double d);()*	Adds a floating-point value.
*add_assoc_string(zval array, char key, char str, int duplicate);()**	Adds a string to the array. The flag `duplicate` specifies whether the string contents have to be copied to Zend internal memory.
*add_assoc_stringl(zval array, char key, char str, uint length, int duplicate); ()**	Adds a string with the desired length `length` to the array. Otherwise, behaves like add_assoc_string().

Tabulka 35-2. Zend's API for Indexed Arrays, Part 1

Function	Description
*add_index_long(zval array, uint idx, long n);()**	Adds an element of type `long`.
*add_index_unset(zval array, uint idx);()**	Adds an unset element.
*add_index_bool(zval array, uint idx, int b);()**	Adds a Boolean element.
*add_index_resource(zval array, uint idx, int r);()**	Adds a resource to the array.
*add_index_double(zval array, uint idx, double d);()**	Adds a floating-point value.
*add_index_string(zval array, uint idx, char str, int duplicate);()*	Adds a string to the array. The flag `duplicate` specifies whether the string contents have to be copied to Zend internal memory.
*add_index_stringl(zval array, uint idx, char str, uint length, int duplicate);()*	Adds a string with the desired length `length` to the array. This function is faster and binary-safe. Otherwise, behaves like add_index_string()().

Tabulka 35-3. Zend's API for Indexed Arrays, Part 2

Function	Description
*add_next_index_long(zval array, long n);()**	Adds an element of type `long`.
*add_next_index_unset(zval array);()**	Adds an unset element.
*add_next_index_bool(zval array, int b);()**	Adds a Boolean element.
*add_next_index_resource(zval array, int r);()**	Adds a resource to the array.
*add_next_index_double(zval array, double d);()**	Adds a floating-point value.
*add_next_index_string(zval array, char str, int duplicate);()*	Adds a string to the array. The flag `duplicate` specifies whether the string contents have to be copied to Zend internal memory.
*add_next_index_stringl(zval array, char str, uint length, int duplicate);()*	Adds a string with the desired length `length` to the array. This function is faster and binary-safe. Otherwise, behaves like add_index_string()().

All these functions provide a handy abstraction to Zend's internal hash API. Of course, you can also use the hash functions directly - for example, if you already have a zval container allocated that you want to insert into an array. This is done using zend_hash_update()() for associative arrays (see 35-3) and zend_hash_index_update() for indexed arrays (see 35-4):

Příklad 35-3. Adding an element to an associative array.

zval *new_array, *new_element; char *key = "element_key"; MAKE_STD_ZVAL(new_array); MAKE_STD_ZVAL(new_element); if(array_init(new_array) == FAILURE) { // do error handling here } ZVAL_LONG(new_element, 10); if(zend_hash_update(new_array->value.ht, key, strlen(key) + 1, (void *)&new_element, sizeof(zval *), NULL) == FAILURE) { // do error handling here }

Příklad 35-4. Adding an element to an indexed array.

zval *new_array, *new_element; int key = 2; MAKE_STD_ZVAL(new_array); MAKE_STD_ZVAL(new_element); if(array_init(new_array) == FAILURE) { // do error handling here } ZVAL_LONG(new_element, 10); if(zend_hash_index_update(new_array->value.ht, key, (void *)&new_element, sizeof(zval *), NULL) == FAILURE) { // do error handling here }

To emulate the functionality of add_next_index_*(), you can use this:

zend_hash_next_index_insert(ht, zval **new_element, sizeof(zval *), NULL)

Note: To return arrays from a function, use array_init() and all following actions on the predefined variable return_value (given as argument to your exported function; see the earlier discussion of the call interface). You do not have to use MAKE_STD_ZVAL on this.

Tip: To avoid having to write new_array->value.ht every time, you can use HASH_OF(new_array), which is also recommended for compatibility and style reasons.

Objects

Since objects can be converted to arrays (and vice versa), you might have already guessed that they have a lot of similarities to arrays in PHP. Objects are maintained with the same hash functions, but there's a different API for creating them.

To initialize an object, you use the function object_init():

zval *new_object; MAKE_STD_ZVAL(new_object); if(object_init(new_object) != SUCCESS) { // do error handling here }
You can use the functions described in 35-4 to add members to your object.

Tabulka 35-4. Zend's API for Object Creation

Function	Description
*add_property_long(zval object, char key, long l);()*	Adds a long to the object.
*add_property_unset(zval object, char key);()*	Adds an unset property to the object.
*add_property_bool(zval object, char key, int b);()*	Adds a Boolean to the object.
*add_property_resource(zval object, char key, long r);()*	Adds a resource to the object.
*add_property_double(zval object, char key, double d);()*	Adds a double to the object.
*add_property_string(zval object, char key, char str, int duplicate);()**	Adds a string to the object.
*add_property_stringl(zval object, char key, char str, uint length, int duplicate);()**	Adds a string of the specified length to the object. This function is faster than add_property_string() and also binary-safe.
*add_property_zval(zval obect, char key, zval container):()**	Adds a `zval` container to the object. This is useful if you have to add properties which aren't simple types like integers or strings but arrays or other objects.

Resources

Resources are a special kind of data type in PHP. The term resources doesn't really refer to any special kind of data, but to an abstraction method for maintaining any kind of information. Resources are kept in a special resource list within Zend. Each entry in the list has a correspondending type definition that denotes the kind of resource to which it refers. Zend then internally manages all references to this resource. Access to a resource is never possible directly - only via a provided API. As soon as all references to a specific resource are lost, a corresponding shutdown function is called.

For example, resources are used to store database links and file descriptors. The de facto standard implementation can be found in the MySQL module, but other modules such as the Oracle module also make use of resources.

Poznámka: In fact, a resource can be a pointer to anything you need to handle in your functions (e.g. pointer to a structure) and the user only has to pass a single resource variable to your function.

To create a new resource you need to register a resource destruction handler for it. Since you can store any kind of data as a resource, Zend needs to know how to free this resource if its not longer needed. This works by registering your own resource destruction handler to Zend which in turn gets called by Zend whenever your resource can be freed (whether manually or automatically). Registering your resource handler within Zend returns you the resource type handle for that resource. This handle is needed whenever you want to access a resource of this type later and is most of time stored in a global static variable within your extension. There is no need to worry about thread safety here because you only register your resource handler once during module initialization.

The Zend function to register your resource handler is defined as:

ZEND_API int zend_register_list_destructors_ex(rsrc_dtor_func_t ld, rsrc_dtor_func_t pld, char *type_name, int module_number);

There are two different kinds of resource destruction handlers you can pass to this function: a handler for normal resources and a handler for persistent resources. Persistent resources are for example used for database connection. When registering a resource, either of these handlers must be given. For the other handler just pass NULL.

zend_register_list_destructors_ex() accepts the following parameters:

`ld`	Normal resource destruction handler callback
`pld`	Pesistent resource destruction handler callback
`type_name`	A string specifying the name of your resource. It's always a good thing to specify an unique name within PHP for the resource type so when the user for example calls `var_dump($resource);` he also gets the name of the resource.
`module_number`	The `module_number` is automatically available in your `PHP_MINIT_FUNCTION` function and therefore you just pass it over.

The return value is an unique integer ID for your resource type.

The resource destruction handler (either normal or persistent resources) has the following prototype:

void resource_destruction_handler(zend_rsrc_list_entry *rsrc TSRMLS_DC);
The passed rsrc is a pointer to the following structure:

typedef struct _zend_rsrc_list_entry { void *ptr; int type; int refcount; } zend_rsrc_list_entry;
The member void *ptr is the actual pointer to your resource.

Now we know how to start things, we define our own resource we want register within Zend. It is only a simple structure with two integer members:

typedef struct { int resource_link; int resource_type; } my_resource;
Our resource destruction handler is probably going to look something like this:

void my_destruction_handler(zend_rsrc_list_entry *rsrc TSRMLS_DC) { // You most likely cast the void pointer to your structure type my_resource *my_rsrc = (my_resource *) rsrc->ptr; // Now do whatever needs to be done with you resource. Closing // Files, Sockets, freeing additional memory, etc. // Also, don't forget to actually free the memory for your resource too! do_whatever_needs_to_be_done_with_the_resource(my_rsrc); }

Poznámka: One important thing to mention: If your resource is a rather complex structure which also contains pointers to memory you allocated during runtime you have to free them before freeing the resource itself!

Now that we have defined

what our resource is and
our resource destruction handler

we can go on and do the rest of the steps:

create a global variable within the extension holding the resource ID so it can be accessed from every function which needs it
define the resource name
write the resource destruction handler
and finally register the handler

// Somewhere in your extension, define the variable for your registered resources.
    // If you wondered what 'le' stands for: it simply means 'list entry'.
    static int le_myresource;

    // It's nice to define your resource name somewhere
    #define le_myresource_name  "My type of resource"

    [...]

    // Now actually define our resource destruction handler
    void my_destruction_handler(zend_rsrc_list_entry *rsrc TSRMLS_DC) {

        my_resource *my_rsrc = (my_resource *) rsrc->ptr;
        do_whatever_needs_to_be_done_with_the_resource(my_rsrc);
    }

    [...]

    PHP_MINIT_FUNCTION(my_extension) {

        // Note that 'module_number' is already provided through the
        // PHP_MINIT_FUNCTION() function definition.

        le_myresource = zend_register_resource_destructors_ex(my_destruction_handler, NULL, le_myresource_name, module_number);

        // You can register additional resources, initialize
        // your global vars, constants, whatever.
    }

To actually register a new resource you use can either use the zend_register_resource() function or the ZEND_REGISTER_RESOURE() macro, both defined in zend_list.h . Although the arguments for both map 1:1 it's a good idea to always use macros to be upwards compatible:

int ZEND_REGISTER_RESOURCE(zval *rsrc_result, void *rsrc_pointer, int rsrc_type);

`rsrc_result`	This is an already initialized `zval *` container.
`rsrc_pointer`	Your resource pointer you want to store.
`rsrc_type`	The type which you received when you registered the resource destruction handler. If you followed the naming scheme this would be `le_myresource`.

The return value is an unique integer identifier for that resource.

What is really going on when you register a new resource is it gets inserted in an internal list in Zend and the result is just stored in the given zval * container:

rsrc_id = zend_list_insert(rsrc_pointer, rsrc_type); if (rsrc_result) { rsrc_result->value.lval = rsrc_id; rsrc_result->type = IS_RESOURCE; } return rsrc_id;
The returned rsrc_id uniquly identifies the newly registered resource. You can use the macro RETURN_RESOURE to return it to the user:

RETURN_RESOURCE(rsrc_id)

Poznámka: It is common practice that if you want to return the resource immidiately to the user you specify the return_value as the zval * container.

Zend now keeps track of all references to this resource. As soon as all references to the resource are lost, the destructor that you previously registered for this resource is called. The nice thing about this setup is that you don't have to worry about memory leakages introduced by allocations in your module - just register all memory allocations that your calling script will refer to as resources. As soon as the script decides it doesn't need them anymore, Zend will find out and tell you.

Now that the user got his resource, at some point he is passing it back to one of your functions. The value.lval inside the zval * container contains the key to your resource and thus can be used to fetch the resource with the following macro: ZEND_FETCH_RESOURCE:

ZEND_FETCH_RESOURCE(rsrc, rsrc_type, rsrc_id, default_rsrc_id, resource_type_name, resource_type)

`rsrc`	This is your pointer which will point to your previously registered resource.
`rsrc_type`	This is the typecast argument for your pointer, e.g. `myresource *`.
`rsrc_id`	This is the address of the `zval `container the user passed to your function, e.g. `&z_resource` if `zval z_resource` is given.
`default_rsrc_id`	This integer specifies the default resource `ID` if no resource could be fetched or -1.
`resource_type_name`	This is the name of the requested resource. It's a string and is used when the resource can't be found or is invalid to form a meaningful error message.
`resource_type`	The `resource_type` you got back when registering the resource destruction handler. In our example this was `le_myresource`.

This macro has no return value. It is for the developers convenience and takes care of TSRMLS arguments passing and also does check if the resource could be fetched. It throws a warning message and returns the current PHP function with NULL if there was a problem retrieving the resource.

To force removal of a resource from the list, use the function zend_list_delete(). You can also force the reference count to increase if you know that you're creating another reference for a previously allocated value (for example, if you're automatically reusing a default database link). For this case, use the function zend_list_addref(). To search for previously allocated resource entries, use zend_list_find(). The complete API can be found in zend_list.h.

Macros for Automatic Global Variable Creation

In addition to the macros discussed earlier, a few macros allow easy creation of simple global variables. These are nice to know in case you want to introduce global flags, for example. This is somewhat bad practice, but Table 35-5 describes macros that do exactly this task. They don't need any zval allocation; you simply have to supply a variable name and value.

Tabulka 35-5. Macros for Global Variable Creation

Macro	Description
`SET_VAR_STRING(name, value)`	Creates a new string.
`SET_VAR_STRINGL(name, value, length)`	Creates a new string of the specified length. This macro is faster than `SET_VAR_STRING` and also binary-safe.
`SET_VAR_LONG(name, value)`	Creates a new long.
`SET_VAR_DOUBLE(name, value)`	Creates a new double.

Creating Constants

Zend supports the creation of true constants (as opposed to regular variables). Constants are accessed without the typical dollar sign ($) prefix and are available in all scopes. Examples include TRUE and FALSE, to name just two.

To create your own constants, you can use the macros in 35-6. All the macros create a constant with the specified name and value.

You can also specify flags for each constant:

CONST_CS - This constant's name is to be treated as case sensitive.
CONST_PERSISTENT - This constant is persistent and won't be "forgotten" when the current process carrying this constant shuts down.

To use the flags, combine them using a inary OR:

// register a new constant of type "long"
     REGISTER_LONG_CONSTANT("NEW_MEANINGFUL_CONSTANT", 324, CONST_CS |
     CONST_PERSISTENT);

There are two types of macros - REGISTER_*_CONSTANT andREGISTER_MAIN_*_CONSTANT. The first type creates constants bound to the current module. These constants are dumped from the symbol table as soon as the module that registered the constant is unloaded from memory. The second type creates constants that remain in the symbol table independently of the module.

Tabulka 35-6. Macros for Creating Constants

Macro	Description
`REGISTER_LONG_CONSTANT(name, value, flags)` `REGISTER_MAIN_LONG_CONSTANT(name, value, flags)`	Registers a new constant of type long.
`REGISTER_DOUBLE_CONSTANT(name, value, flags)` `REGISTER_MAIN_DOUBLE_CONSTANT(name, value, flags)`	Registers a new constant of type double.
`REGISTER_STRING_CONSTANT(name, value, flags)` `REGISTER_MAIN_STRING_CONSTANT(name, value, flags)`	Registers a new constant of type string. The specified string must reside in Zend's internal memory.
`REGISTER_STRINGL_CONSTANT(name, value, length, flags)` `REGISTER_MAIN_STRINGL_CONSTANT(name, value, length, flags)`	Registers a new constant of type string. The string length is explicitly set to `length`. The specified string must reside in Zend's internal memory.

Kapitola 36. Duplicating Variable Contents: The Copy Constructor

Sooner or later, you may need to assign the contents of one zval container to another. This is easier said than done, since the zval container doesn't contain only type information, but also references to places in Zend's internal data. For example, depending on their size, arrays and objects may be nested with lots of hash table entries. By assigning one zval to another, you avoid duplicating the hash table entries, using only a reference to them (at most).

To copy this complex kind of data, use the copy constructor. Copy constructors are typically defined in languages that support operator overloading, with the express purpose of copying complex types. If you define an object in such a language, you have the possibility of overloading the "=" operator, which is usually responsible for assigning the contents of the lvalue (result of the evaluation of the left side of the operator) to the rvalue (same for the right side).

Overloading means assigning a different meaning to this operator, and is usually used to assign a function call to an operator. Whenever this operator would be used on such an object in a program, this function would be called with the lvalue and rvalue as parameters. Equipped with that information, it can perform the operation it intends the "=" operator to have (usually an extended form of copying).

This same form of "extended copying" is also necessary for PHP's zval containers. Again, in the case of an array, this extended copying would imply re-creation of all hash table entries relating to this array. For strings, proper memory allocation would have to be assured, and so on.

Zend ships with such a function, called zend_copy_ctor() (the previous PHP equivalent was pval_copy_constructor()).

A most useful demonstration is a function that accepts a complex type as argument, modifies it, and then returns the argument:

zval *parameter;
   
if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "z", &parameter) == FAILURE)
   return;
}
   
// do modifications to the parameter here

// now we want to return the modified container:
*return_value == *parameter;
zval_copy_ctor(return_value);

The first part of the function is plain-vanilla argument retrieval. After the (left out) modifications, however, it gets interesting: The container of parameter is assigned to the (predefined) return_value container. Now, in order to effectively duplicate its contents, the copy constructor is called. The copy constructor works directly with the supplied argument, and the standard return values are FAILURE on failure and SUCCESS on success.

If you omit the call to the copy constructor in this example, both parameter and return_value would point to the same internal data, meaning that return_value would be an illegal additional reference to the same data structures. Whenever changes occurred in the data that parameter points to, return_value might be affected. Thus, in order to create separate copies, the copy constructor must be used.

The copy constructor's counterpart in the Zend API, the destructor zval_dtor(), does the opposite of the constructor.

Kapitola 37. Returning Values

Returning values from your functions to PHP was described briefly in an earlier section; this section gives the details. Return values are passed via the return_value variable, which is passed to your functions as argument. The return_value argument consists of a zval container (see the earlier discussion of the call interface) that you can freely modify. The container itself is already allocated, so you don't have to run MAKE_STD_ZVAL on it. Instead, you can access its members directly.

To make returning values from functions easier and to prevent hassles with accessing the internal structures of the zval container, a set of predefined macros is available (as usual). These macros automatically set the correspondent type and value, as described in 37-1 and 37-2.

Poznámka: The macros in 37-1 automatically return from your function, those in 37-2 only set the return value; they don't return from your function.

Tabulka 37-1. Predefined Macros for Returning Values from a Function

Macro	Description
`RETURN_RESOURCE(resource)`	Returns a resource.
`RETURN_BOOL(bool)`	Returns a Boolean.
`RETURN_NULL()`	Returns nothing (a NULL value).
`RETURN_LONG(long)`	Returns a long.
`RETURN_DOUBLE(double)`	Returns a double.
`RETURN_STRING(string, duplicate)`	Returns a string. The `duplicate` flag indicates whether the string should be duplicated using estrdup().
`RETURN_STRINGL(string, length, duplicate)`	Returns a string of the specified length; otherwise, behaves like `RETURN_STRING`. This macro is faster and binary-safe, however.
`RETURN_EMPTY_STRING()`	Returns an empty string.
`RETURN_FALSE`	Returns Boolean false.
`RETURN_TRUE`	Returns Boolean true.

Tabulka 37-2. Predefined Macros for Setting the Return Value of a Function

Macro	Description
`RETVAL_RESOURCE(resource)`	Sets the return value to the specified resource.
`RETVAL_BOOL(bool)`	Sets the return value to the specified Boolean value.
`RETVAL_NULL`	Sets the return value to NULL.
`RETVAL_LONG(long)`	Sets the return value to the specified long.
`RETVAL_DOUBLE(double)`	Sets the return value to the specified double.
`RETVAL_STRING(string, duplicate)`	Sets the return value to the specified string and duplicates it to Zend internal memory if desired (see also `RETURN_STRING`).
`RETVAL_STRINGL(string, length, duplicate)`	Sets the return value to the specified string and forces the length to become `length` (see also `RETVAL_STRING`). This macro is faster and binary-safe, and should be used whenever the string length is known.
`RETVAL_EMPTY_STRING`	Sets the return value to an empty string.
`RETVAL_FALSE`	Sets the return value to Boolean false.
`RETVAL_TRUE`	Sets the return value to Boolean true.

Complex types such as arrays and objects can be returned by using array_init() and object_init(), as well as the corresponding hash functions on return_value. Since these types cannot be constructed of trivial information, there are no predefined macros for them.

Kapitola 38. Printing Information

Often it's necessary to print messages to the output stream from your module, just as print() would be used within a script. PHP offers functions for most generic tasks, such as printing warning messages, generating output for phpinfo(), and so on. The following sections provide more details. Examples of these functions can be found on the CD-ROM.

zend_printf()

zend_printf() works like the standard printf(), except that it prints to Zend's output stream.

zend_error()

zend_error() can be used to generate error messages. This function accepts two arguments; the first is the error type (see zend_errors.h), and the second is the error message.

zend_error(E_WARNING, "This function has been called with empty arguments");
38-1 shows a list of possible values (see 38-1). These values are also referred to in php.ini. Depending on which error type you choose, your messages will be logged.

Tabulka 38-1. Zend's Predefined Error Messages.

Error	Description
`E_ERROR`	Signals an error and terminates execution of the script immediately .
`E_WARNING`	Signals a generic warning. Execution continues.
`E_PARSE`	Signals a parser error. Execution continues.
`E_NOTICE`	Signals a notice. Execution continues. Note that by default the display of this type of error messages is turned off in `php.ini`.
`E_CORE_ERROR`	Internal error by the core; shouldn't be used by user-written modules.
`E_COMPILE_ERROR`	Internal error by the compiler; shouldn't be used by user-written modules.
`E_COMPILE_WARNING`	Internal warning by the compiler; shouldn't be used by user-written modules.

Obrázek 38-1. Display of warning messages in the browser.

Including Output in phpinfo()

After creating a real module, you'll want to show information about the module in phpinfo() (in addition to the module name, which appears in the module list by default). PHP allows you to create your own section in the phpinfo() output with the ZEND_MINFO() function. This function should be placed in the module descriptor block (discussed earlier) and is always called whenever a script calls phpinfo().

PHP automatically prints a section in phpinfo() for you if you specify the ZEND_MINFO function, including the module name in the heading. Everything else must be formatted and printed by you.

Typically, you can print an HTML table header using php_info_print_table_start() and then use the standard functions php_info_print_table_header() and php_info_print_table_row(). As arguments, both take the number of columns (as integers) and the column contents (as strings). 38-1 shows a source example and its output. To print the table footer, use php_info_print_table_end().

Příklad 38-1. Source code and screenshot for output in phpinfo().

php_info_print_table_start();
php_info_print_table_header(2, "First column", "Second column");
php_info_print_table_row(2, "Entry in first row", "Another entry");
php_info_print_table_row(2, "Just to fill", "another row here");
php_info_print_table_end();

Execution Information

You can also print execution information, such as the current file being executed. The name of the function currently being executed can be retrieved using the function get_active_function_name(). This function returns a pointer to the function name and doesn't accept any arguments. To retrieve the name of the file currently being executed, use zend_get_executed_filename(). This function accesses the executor globals, which are passed to it using the TSRMLS_C macro. The executor globals are automatically available to every function that's called directly by Zend (they're part of the INTERNAL_FUNCTION_PARAMETERS described earlier in this chapter). If you want to access the executor globals in another function that doesn't have them available automatically, call the macro TSRMLS_FETCH() once in that function; this will introduce them to your local scope.

Finally, the line number currently being executed can be retrieved using the function zend_get_executed_lineno(). This function also requires the executor globals as arguments. For examples of these functions, see 38-2.

Příklad 38-2. Printing execution information.

zend_printf("The name of the current function is %s<br>", get_active_function_name(TSRMLS_C));
zend_printf("The file currently executed is %s<br>", zend_get_executed_filename(TSRMLS_C));
zend_printf("The current line being executed is %i<br>", zend_get_executed_lineno(TSRMLS_C));

Kapitola 39. Startup and Shutdown Functions

Startup and shutdown functions can be used for one-time initialization and deinitialization of your modules. As discussed earlier in this chapter (see the description of the Zend module descriptor block), there are global, module, and request startup and shutdown events.

The global startup functions are called once when PHP starts up; similarly, the global shutdown functions are called once when PHP shuts down. Please note that they're really only called once, not when a new Apache process is being created!

The module startup and shutdown functions are called whenever a module is loaded and needs initialization; the request startup and shutdown functions are called every time a request is processed (meaning that a file is being executed).

For dynamic extensions, module and request startup/shutdown events happen at the same time.

Declaration and implementation of these functions can be done with macros; see the earlier section "Declaration of the Zend Module Block" for details.

Kapitola 40. Calling User Functions

You can call user functions from your own modules, which is very handy when implementing callbacks; for example, for array walking, searching, or simply for event-based programs.

User functions can be called with the function call_user_function_ex(). It requires a hash value for the function table you want to access, a pointer to an object (if you want to call a method), the function name, return value, number of arguments, argument array, and a flag indicating whether you want to perform zval separation.

ZEND_API int call_user_function_ex(HashTable *function_table, zval *object,
zval *function_name, zval **retval_ptr_ptr,
int param_count, zval **params[],
int no_separation);

Note that you don't have to specify both function_table and object; either will do. If you want to call a method, you have to supply the object that contains this method, in which case call_user_function()automatically sets the function table to this object's function table. Otherwise, you only need to specify function_table and can set object to NULL.

Usually, the default function table is the "root" function table containing all function entries. This function table is part of the compiler globals and can be accessed using the macro CG. To introduce the compiler globals to your function, call the macro TSRMLS_FETCH once.

The function name is specified in a zval container. This might be a bit surprising at first, but is quite a logical step, since most of the time you'll accept function names as parameters from calling functions within your script, which in turn are contained in zval containers again. Thus, you only have to pass your arguments through to this function. This zval must be of type IS_STRING.

The next argument consists of a pointer to the return value. You don't have to allocate memory for this container; the function will do so by itself. However, you have to destroy this container (using zval_dtor()) afterward!

Next is the parameter count as integer and an array containing all necessary parameters. The last argument specifies whether the function should perform zval separation - this should always be set to 0. If set to 1, the function consumes less memory but fails if any of the parameters need separation.

40-1 shows a small demonstration of calling a user function. The code calls a function that's supplied to it as argument and directly passes this function's return value through as its own return value. Note the use of the constructor and destructor calls at the end - it might not be necessary to do it this way here (since they should be separate values, the assignment might be safe), but this is bulletproof.

Příklad 40-1. Calling user functions.

zval **function_name;
zval *retval;

if((ZEND_NUM_ARGS() != 1) || (zend_get_parameters_ex(1, &function_name) != SUCCESS))
{
    WRONG_PARAM_COUNT;
}

if((*function_name)->type != IS_STRING)
{
    zend_error(E_ERROR, "Function requires string argument");
}

TSRMSLS_FETCH();

if(call_user_function_ex(CG(function_table), NULL, *function_name, &retval, 0, NULL, 0) != SUCCESS)
{
    zend_error(E_ERROR, "Function call failed");
}

zend_printf("We have %i as type<br>", retval->type);

*return_value = *retval;
zval_copy_ctor(return_value);
zval_ptr_dtor(&retval);

<?php

dl("call_userland.so");

function test_function()
{

    print("We are in the test function!<br>");

    return("hello");

}

$return_value = call_userland("test_function");

print("Return value: \"$return_value\"<br>");
?>

Kapitola 41. Initialization File Support

PHP 4 features a redesigned initialization file support. It's now possible to specify default initialization entries directly in your code, read and change these values at runtime, and create message handlers for change notifications.

To create an .ini section in your own module, use the macros PHP_INI_BEGIN() to mark the beginning of such a section and PHP_INI_END() to mark its end. In between you can use PHP_INI_ENTRY() to create entries.

PHP_INI_BEGIN() PHP_INI_ENTRY("first_ini_entry", "has_string_value", PHP_INI_ALL, NULL) PHP_INI_ENTRY("second_ini_entry", "2", PHP_INI_SYSTEM, OnChangeSecond) PHP_INI_ENTRY("third_ini_entry", "xyz", PHP_INI_USER, NULL) PHP_INI_END()
The PHP_INI_ENTRY() macro accepts four parameters: the entry name, the entry value, its change permissions, and a pointer to a change-notification handler. Both entry name and value must be specified as strings, regardless of whether they really are strings or integers.

The permissions are grouped into three sections:PHP_INI_SYSTEM allows a change only directly in the php3.ini file; PHP_INI_USER allows a change to be overridden by a user at runtime using additional configuration files, such as .htaccess; and PHP_INI_ALL allows changes to be made without restrictions. There's also a fourth level, PHP_INI_PERDIR, for which we couldn't verify its behavior yet.

The fourth parameter consists of a pointer to a change-notification handler. Whenever one of these initialization entries is changed, this handler is called. Such a handler can be declared using the PHP_INI_MH macro:

PHP_INI_MH(OnChangeSecond); // handler for ini-entry "second_ini_entry" // specify ini-entries here PHP_INI_MH(OnChangeSecond) { zend_printf("Message caught, our ini entry has been changed to %s<br>", new_value); return(SUCCESS); }
The new value is given to the change handler as string in the variable new_value. When looking at the definition of PHP_INI_MH, you actually have a few parameters to use:

#define PHP_INI_MH(name) int name(php_ini_entry *entry, char *new_value, uint new_value_length, void *mh_arg1, void *mh_arg2, void *mh_arg3)
All these definitions can be found in php_ini.h. Your message handler will have access to a structure that contains the full entry, the new value, its length, and three optional arguments. These optional arguments can be specified with the additional macros PHP_INI_ENTRY1 (allowing one additional argument), PHP_INI_ENTRY2 (allowing two additional arguments), and PHP_INI_ENTRY3 (allowing three additional arguments).

The change-notification handlers should be used to cache initialization entries locally for faster access or to perform certain tasks that are required if a value changes. For example, if a constant connection to a certain host is required by a module and someone changes the hostname, automatically terminate the old connection and attempt a new one.

Access to initialization entries can also be handled with the macros shown in 41-1.

Tabulka 41-1. Macros to Access Initialization Entries in PHP

Macro	Description
`INI_INT(name)`	Returns the current value of entry `name` as integer (long).
`INI_FLT(name)`	Returns the current value of entry `name` as float (double).
`INI_STR(name)`	Returns the current value of entry `name` as string. Note: This string is not duplicated, but instead points to internal data. Further access requires duplication to local memory.
`INI_BOOL(name)`	Returns the current value of entry `name` as Boolean (defined as `zend_bool`, which currently means `unsigned char`).
`INI_ORIG_INT(name)`	Returns the original value of entry `name` as integer (long).
`INI_ORIG_FLT(name)`	Returns the original value of entry `name` as float (double).
`INI_ORIG_STR(name)`	Returns the original value of entry `name` as string. Note: This string is not duplicated, but instead points to internal data. Further access requires duplication to local memory.
`INI_ORIG_BOOL(name)`	Returns the original value of entry `name` as Boolean (defined as `zend_bool`, which currently means `unsigned char`).

Finally, you have to introduce your initialization entries to PHP. This can be done in the module startup and shutdown functions, using the macros REGISTER_INI_ENTRIES() and UNREGISTER_INI_ENTRIES():

ZEND_MINIT_FUNCTION(mymodule) { REGISTER_INI_ENTRIES(); } ZEND_MSHUTDOWN_FUNCTION(mymodule) { UNREGISTER_INI_ENTRIES(); }

Kapitola 42. Where to Go from Here

You've learned a lot about PHP. You now know how to create dynamic loadable modules and statically linked extensions. You've learned how PHP and Zend deal with internal storage of variables and how you can create and access these variables. You know quite a set of tool functions that do a lot of routine tasks such as printing informational texts, automatically introducing variables to the symbol table, and so on.

Even though this chapter often had a mostly "referential" character, we hope that it gave you insight on how to start writing your own extensions. For the sake of space, we had to leave out a lot; we suggest that you take the time to study the header files and some modules (especially the ones in the ext/standard directory and the MySQL module, as these implement commonly known functionality). This will give you an idea of how other people have used the API functions - particularly those that didn't make it into this chapter.

Kapitola 43. Reference: Some Configuration Macros

`config.m4`

The file config.m4 is processed by buildconf and must contain all the instructions to be executed during configuration. For example, these can include tests for required external files, such as header files, libraries, and so on. PHP defines a set of macros that can be used in this process, the most useful of which are described in 43-1.

Tabulka 43-1. M4 Macros for config.m4

Macro	Description
`AC_MSG_CHECKING(message)`	Prints a "checking <message>" text during `configure`.
`AC_MSG_RESULT(value)`	Gives the result to `AC_MSG_CHECKING`; should specify either `yes` or `no` as `value`.
`AC_MSG_ERROR(message)`	Prints `message` as error message during `configure` and aborts the script.
`AC_DEFINE(name,value,description)`	Adds `#define` to `php_config.h` with the value of `value` and a comment that says `description` (this is useful for conditional compilation of your module).
`AC_ADD_INCLUDE(path)`	Adds a compiler include path; for example, used if the module needs to add search paths for header files.
`AC_ADD_LIBRARY_WITH_PATH(libraryname,librarypath)`	Specifies an additional library to link.
`AC_ARG_WITH(modulename,description,unconditionaltest,conditionaltest)`	Quite a powerful macro, adding the module with `description` to the `configure --help` output. PHP checks whether the option `--with-<modulename>` is given to the `configure` script. If so, it runs the script `unconditionaltest` (for example, `--with-myext=yes`), in which case the value of the option is contained in the variable `$withval`. Otherwise, it executes `conditionaltest`.
`PHP_EXTENSION(modulename, [shared])`	This macro is a must to call for PHP to configure your extension. You can supply a second argument in addition to your module name, indicating whether you intend compilation as a shared module. This will result in a definition at compile time for your source as `COMPILE_DL_<modulename>`.

Kapitola 44. API Macros

A set of macros was introduced into Zend's API that simplify access to zval containers (see 44-1).

Tabulka 44-1. API Macros for Accessing zval Containers

Macro	Refers to
`Z_LVAL(zval)`	`(zval).value.lval`
`Z_DVAL(zval)`	`(zval).value.dval`
`Z_STRVAL(zval)`	`(zval).value.str.val`
`Z_STRLEN(zval)`	`(zval).value.str.len`
`Z_ARRVAL(zval)`	`(zval).value.ht`
`Z_LVAL_P(zval)`	`(*zval).value.lval`
`Z_DVAL_P(zval)`	`(*zval).value.dval`
`Z_STRVAL_P(zval_p)`	`(*zval).value.str.val`
`Z_STRLEN_P(zval_p)`	`(*zval).value.str.len`
`Z_ARRVAL_P(zval_p)`	`(*zval).value.ht`
`Z_LVAL_PP(zval_pp)`	`(**zval).value.lval`
`Z_DVAL_PP(zval_pp)`	`(**zval).value.dval`
`Z_STRVAL_PP(zval_pp)`	`(**zval).value.str.val`
`Z_STRLEN_PP(zval_pp)`	`(**zval).value.str.len`
`Z_ARRVAL_PP(zval_pp)`	`(**zval).value.ht`

VI. FAQ: Často zodpovídané otázky

Obsah
45. Obecné informace
46. E-mailové konference (mailing lists)
47. Získání PHP
48. Záležitosti databází
49. Instalace
50. Sestavovací (kompilační) problémy
51. Používání PHP
52. PHP a HTML
53. PHP a COM
54. PHP a jiné jazyky
55. Přechod z PHP 2 na PHP 3
56. Přechod z PHP 3 na PHP 4
57. Ostatní otázky

Kapitola 45. Obecné informace

Tato sekce se zabývá obecnými otázkami okolo PHP: co to je a co to dělá.

1. Co je to PHP?
2. Co znamená zkratka PHP?
3. Jaký je vztah mezi verzemi?
4. Mohu současně pouštět více verzí PHP?
5. Jaké jsou rozdíly mezi PHP 3 a PHP 4?
6. Myslím, že jsem našel chybu! Komu to mám říct?

1. Co je to PHP?

Z předsádky manuálu:

PHP je skriptovací jazyk vkládaný do HTML. Mnoho jeho syntaxe je vypůjčeno z C, Javy a Perlu s několika přidanými prostředky specifickými pro PHP. Cílem jazyka je umožnit vývojářům webů rychleji psát dynamicky generované stránky.

Milý úvod do PHP od Stiga Sæther Bakkena najdete tady na stránkách Zendu. Volně k dispozici je také mnoho materiálů PHP konference.

2. Co znamená zkratka PHP?

PHP je zkratka pro PHP: Hypertext Preprocessor. Mnoho lidí může mást, že první slovo akronymu je také akronym. Tomuto typu zkratek se říká rekurzívní akronym. Zvědavci mohou navštívit Free On-Line Dictionary of Computing, kde najdou více informací o rekurzívních akronymech.

3. Jaký je vztah mezi verzemi?

PHP/FI 2.0 je časná a již nepodporovaná verze PHP. PHP 3 je následník PHP/FI 2.0 a je mnohem lepší. PHP 4 je zatím poslední generací PHP a má pod kapotou Zend engine.

4. Mohu současně pouštět více verzí PHP?

Ano. Podívejte se do souboru INSTALL, který je přiložen k distribuci zdrojových souborů PHP 4. Přečtěte si i příslušný dodatek.

5. Jaké jsou rozdíly mezi PHP 3 a PHP 4?

Existuje několik článků, které o tom napsali autoři PHP 4. Tady je seznam některých důležitějších nových prvků:

Rozšířený API modul
Zobecněný sestavovací (kompilační) proces pod UNIXem
Generické rozhraní pro WWW servery, které podporuje také multithreadové servery
Vylepšený zvýrazňovač syntaxe
Nativní podpora HTTP sessions
Podpora výstupního bufferingu
Silnější konfigurační systém
Reference counting

Podívejte se laskavě na What's new in PHP 4 overview, kde najdete detailní vysvětlení těchto prvků a ještě mnohem víc. Pokud přecházíte z PHP 3 na PHP 4, přečtěte si také příslušný dodatek.

6. Myslím, že jsem našel chybu! Komu to mám říct?

Měli byste navštívit databázi chyb (PHP Bug Database) a ujistit se, zda nalezená chyba již není v seznamu známých chyb. Pokud ji tam nenajdete, použijte formulář pro ohlašování chyb. Je důležité použít databázi chyb namísto posílání zprávy do distribučního seznamu, protože chyba bude mít přiřazeno své číslo a bude potom možné, abyste se sem později vrátili a zkontrolovali stav chyby. Chybovou databázi najdete na http://bugs.php.net/.

Kapitola 46. E-mailové konference (mailing lists)

Tato část se zabývá záležitostmi o tom, jak můžete navázat kontakt s PHP komunitou. Nejlepším způsobem jsou e-mailové konference.

Pozn. překladatele: Čeština nemá adekvátní termín pro "mailing list". Protože se běžně používá termínů "e-mailová konference" nebo "konference", budu je používat i zde, i když to není úplně nejlepší řešení.

1. Existují nějaké e-mailové konference pro PHP?
2. Existují ještě jiné komunity?
3. Pomoc! Nedaří se mi přihlásit/odhlásit se do/z konference!
4. Existuje někde archiv konferencí?
5. Na co se mohu ptát v konferenci?
6. Jaké informace mám přiložit k příspěvku do konference?

1. Existují nějaké e-mailové konference pro PHP?

Samozřejmě! Je mnoho konferencí pro různé záležitosti. Kompletní seznam těchto konferencí můžete najít na naší stránce Podpora.

Většina konferencí patří do třídy php-general, tedy obecné záležitosti PHP. K přihlášení pošlete zprávu na php-general-subscribe@lists.php.net. Do předmětu zprávy ani jejího těla nemusíte vkládat nic speciálního. Odhlásíte se posláním zprávy na php-general-unsubscribe@lists.php.net.

Přihlásit nebo odhlásit se můžete také pomocí rozhraní na webu na stránce Podpora.

2. Existují ještě jiné komunity?

Je jich nespočetně po celém světě. Máme např. odkazy na některé IRC servery a konference v cizích jazycích - na stránce Podpora.

3. Pomoc! Nedaří se mi přihlásit/odhlásit se do/z konference!

Pokud máte problémy s přihlašováním nebo odhlašováním konference php-general, může to být proto, že její software nemůže vyhodnotit správnou e-mailovou adresu k použití. Pokud by vaše adresa byla joeblow@example.com, můžete poslat přihlašovací požadavek na php-general-subscribe-joeblow=example.com@lists.php.net, resp. odhlašovací na php-general-unsubscribe-joeblow=example.com@lists.php.net. Pro ostatní konference použijte obdobné adresy.

4. Existuje někde archiv konferencí?

Ano, seznam archivů najdete na stránce Podpora. Příspěvky do konferencí se archivují také jako zprávy služby news (protokol NNTP). Server této služby je k dispozici na news://news.php.net/. Existuje také experimentální webovské rozhraní pro news server na http://news.php.net/

5. Na co se mohu ptát v konferenci?

Jak je PHP den ze dne stále populárnější, provoz v konferenci php-general narůstal a nyní přichází 150-200 příspěvků denně. Kvůli tomu je v zájmu každého, aby používal tuto konferenci až jako poslední možnost poté, co hledal všude jinde.

Než něco pošlete do konference, podívejte se prosím do FAQ a do manuálu, zda nemůžete najít odpověd tam. Pokud ji nenajdete, prohlédněte si archivy konferencí (viz výše). Když máte problémy s instalací nebo konfigurací PHP, přečtěte si prosím všechnu přiloženou dokumentaci a soubory README. Pokud stále nemůžete najít nic, co by vám pomohlo, jste více než vítáni v konferenci.

6. Jaké informace mám přiložit k příspěvku do konference?

Příspěvky jako "PHP mi nechce fungovat! Pomozte mi! Co mám špatně?" jsou absolutně k ničemu. Pokud máte problémy se spouštěním a během PHP, musíte napsat, na jakém operačním systému ho spouštíte, o kterou verzi PHP se jedná, jak jste ji získali (předkompilovaný balík, CVS, RPM apod.), co jste s ním udělali, kde to uvázlo, a přesnou chybovou zprávu.

To platí úplně stejně i pro jiné problémy. Měli byste přiložit informace o tom, co jste dělali, kde to uvázlo, co jste s tím zkoušeli dělat a, pokud to lze, přesnou chybovou zprávu. Máte-li problémy se zdrojovým kódem, je třeba přiložit ten kus kódu, který nepracuje. Nepřikládejte více kódu, než je třeba! Příspěvek by byl hůře čitelný a mnoho lidí by ho kvůli tomu přeskočilo. Pokud si nejste jisti, kolik informací máte přiložit do zprávy, je lépe přidat více než méně.

Jinou důležitou věcí, kterou je třeba mít na paměti, je sumarizace problému v předmětu zprávy. Předmět typu "POMOZTEEE! nebo "Co je to za problém?" bude většina čtenářů ignorovat.

Kapitola 47. Získání PHP

Tato část obsahuje detaily o umístění PHP downloadu a záležitostech operačních systémů.

1. Kde mohu získat PHP?
2. Jsou k dispozici předkompilované binární verze?
3. Kde mohu získat knihovny potřebné pro kompilaci některých volitelných rozšíření PHP?
4. Jak zařídím, aby tyto knihovny fungovaly?
5. Získal jsem poslední verzi zdrojového kódu PHP z CVS repozitáře, co potřebuji ke kompilaci na Windows?
6. Kde najdu Browser Capabilities File?

1. Kde mohu získat PHP?

PHP můžete stáhnout z kteréhokoli bodu, který je součástí sítě PHP serverů. Najdete je na http://www.php.net/. Můžete také použít anonymní CVS přístup, čímž získáte absolutně nejnovější verzi zdrojových souborů. Více informací najdete na http://cvs.php.net/.

2. Jsou k dispozici předkompilované binární verze?

Předkompilované verze distribuujeme pouze pro systémy Windows, protože nejsme schopni zkompilovat PHP pro všechny hlavní platformy Linux/UNIX se všemi kombinacemí rozšíření. Také si uvědomte, že mnoho distribucí Linuxu dnes přímo obsahuje PHP. Binární soubory pro Windows si můžete stáhnout z naší stránky Download, pro binární soubory pro Linux navštivte stránky distribucí Linuxu.

3. Kde mohu získat knihovny potřebné pro kompilaci některých volitelných rozšíření PHP?

Poznámka: Knihovny označené * (hvězdičkou) nejsou vláknově bezpečné a neměly by se používat s PHP jako modulem do multithreadových serverů pod Windows (IIS, Netscape). V UNIXu na tom nezáleží.

LDAP (unix).
LDAP* (unix).
LDAP (unix/win) : Netscape Directory (LDAP) SDK 1.1.
free LDAP server.
Berkeley DB2 (Unix/Win) : http://www.sleepycat.com/.
SNMP* (Unix): .
GD* (Unix/Win).
mSQL* (Win).
mSQL* (Unix).
PostgreSQL (Unix).
IMAP* (Win/Unix).
Sybase-CT* (Linux, libc5) : Available locally.
FreeType (libttf):.
ZLib (Unix/Win32).
expat XML parser (Unix/Win32).
PDFLib.
mcrypt.
mhash.
t1lib.
dmalloc.
aspell.
readline.

4. Jak zařídím, aby tyto knihovny fungovaly?

Musíte se řídit instrukcemi dodanými s příslušnou knihovnou. Některé knihovny se automaticky detekují při spuštění skriptu 'configure' pro PHP (např. knihovna GD), jiné musíte aktivovat pomocí parametru '--with-EXTENSION' pro 'configure'. Seznam těchto parametrů získáte spuštěním 'configure --help'.

5. Získal jsem poslední verzi zdrojového kódu PHP z CVS repozitáře, co potřebuji ke kompilaci na Windows?

V první řadě musíte mít Microsoft Visual C++ verze 6 (MSVC++ 5 také postačí, ale my používáme verzi 6) a budete potřebovat nějaké podpůrné soubory. Podívejte se do sekce manuálu o kompilaci PHP pod Windows.

6. Kde najdu Browser Capabilities File?

Je to soubor browscap.ini na http://www.cyscape.com/asp/browscap/.

Kapitola 48. Záležitosti databází

Tato sekce se zabývá častými otázkami okolo vztahu PHP a databází. Ano, PHP dnes může virtuálně přistupovat ke kterékoli dostupné databázi.

1. Slyšel jsem, že lze z PHP přistupovat k Microsoft SQL Serveru. Jak?
2. Lze přistupovat k databázím Microsoft Access?
3. Upgradoval jsem na PHP 4 a MySQL mi teď hlásí "Warning: MySQL: Unable to save result set in ...". Co se děje?
4. Po instalaci podpory sdíleného MySQL havaruje Apache v momentě, kdy načítá libphp4.so. Lze to vyřešit?
5. Proč dostávám chybu, která vypadá nějak takto: "Warning: 0 is not a MySQL result index in <file> on line <x>" nebo "Warning: Supplied argument is not a valid MySQL result resource in <file> on line <x>?

1. Slyšel jsem, že lze z PHP přistupovat k Microsoft SQL Serveru. Jak?

Na strojích s Windows můžete jednoduše použít zabudovanou podporu ODBC a správný ovladač ODBC.

Na Unixových strojích můžete k přístupu na Microsoft SQL Servery použít ovladač Sybase-CT, protože tyto protokoly jsou (alespoň z většiny) kompatibilní. V Sybase připravili volnou verzi potřebných knihoven pro Linux. Pro jiné Unixové systémy musíte kontaktovat Sybase k získání správných knihoven. Podívejte se také na odpověď na příští otázku.

2. Lze přistupovat k databázím Microsoft Access?

Ano. Pokud pracujete pod Windows 9x/Me nebo NT/2000, všechny potřebné nástroje již máte k dispozici - můžete použít ODBC a ovladače pro ODBC k databázím Microsoft Access.

Pokud používáte PHP na Unixu a chcete komunikovat s databázemi MS Access běžících na Windows, budete potřebovat ODBC ovladače pro Unix. OpenLink Software má unixové ovladače pro ODBC, které zde vyhoví. Existuje pilotní program, kdy si můžete stáhnout zkušební kopii, která má neomezenou zkušební dobu; ceny komerční verze s podporou začínají na 675 USD.

Jinou alternativou je použít SQL server, který má ODBC ovladače pro Windows a použít ho k uložení dat, ke kterým pak můžete přistupovat z aplikace Microsoft Access (pomocí ODBC) a z PHP (pomocí vestavěných ovladačů), nebo použít souborový meziformát, kterému rozumí Access i PHP (např. obyčejné soubory nebo databáze dBase). K tomuto bodu Tim Hayes z OpenLink soiftware píše:

Použití jiné databáze jako meziformátu není dobrý nápad, pokud můžete použít ODBC z PHP přímo na vaší databázi - např. pomocí ovladačů od OpenLink software. Když meziformát použít musíte, OpenLink nyní uvolnil Virtuoso (virtuální databázový stroj) pro WinNT, Linux a jiné unixové platformy. Navštivte prosím naši website a zdarma si ho stáhněte.

Jednou z prověřených možností je použít MySQL a jeho ODBC ovladače pro Windows a synchronizace databází. Steve Lawrence píše:

Nainstalujte si na svou platformu MySQL podle přiložených instrukcí. Nejnovější verzi získáte na http://www.mysql.com/ (stahujte z nejbližšího zrcadla!). Není třeba žádná zvláštní konfigurace kromě toho, že když instalujete databázi a konfigurujete uživatelský účet, měli byste do pole "host" přidat % nebo název počítače s Windows, na kterém chcete MySQL spouštět. Poznamenejte si název serveru, uživatelské jméno a heslo.
Stáhněte si ovladač MyODBC pro Windows ze stránek MySQL. Nejnovější verze je myodbc-2_50_19-win95.zip (k dispozici také verze pro NT, stejně tak i zdrojový kód). Nainstalujte ho na počítač s Windows. Funkci můžete otestovat pomocí přiložených utilit.
Vytvořte uživatelský nebo systémový dsn v administrátoru ODBC, umístěném v ovládacích panelech. Zvolte název dsn, vložte název počítače, heslo, port apod. pro databázi MySQL nakonfigurovanou v kroku 1.
Nainstalujte plnou instalaci Accessu, což zajistí, že budou k dispozici všechny doplňky; budete potřebovat alespoň podporu ODBC a správu propojených tabulek.
A teď to nejzábavnější! Vytvořte novou databázi v Accessu. Klikněte pravým tlačítkem v okně tabulek a vyberte "Propojit tabulky", nebo pod nabídkou "Soubor" vyberte "Načíst externí data" a potom "Propojit tabulky". Až se otevře dialog, vyberte soubory typu ODBC. Zvolte systémový dsn a název dsn vytvořeného v kroku 3. Vyberte tabulku k propojení, stiskněte "OK" a je to"! Nyní můžete otevřít tabulku a přidat/smazat/upravovat data na vašem MySQL serveru! Můžete také vytvářet dotazy, importovat/exportovat tabulky do MySQL, vytvářet formuláře a sestavy atd.

Tipy a triky:

Můžete vytvořit tabulky v Accessu, exportovat je do MySQL a potom propojit zpět. To urychluje návrh tabulek.
Když vytváříte tabulky v Accessu, musíte mít definován primární klíč kvůli zápisu do tabulky. Ujistěte se, že jste primární klíč v MySQL vytvořili před propojením do Accessu.
Pokud změníte tabulku v MySQL, musíte ji znovu připojit do Accessu. Go to tools>add-ins>linked table manager, cruise to your ODBC DSN, and select the table to re-link from there. you can also move your dsn source around there, just hit the always prompt for new location checkbox before pressing ok.

3. Upgradoval jsem na PHP 4 a MySQL mi teď hlásí "Warning: MySQL: Unable to save result set in ...". Co se děje?

Nejspíše se stalo to, že bylo PHP 4 zkompilováno s volbout '--with-mysql' bez specifikace cesty k MySQL. To znamená, že PHP používá svoji vestavěnou klientskou knihovnu. Pokud na vašem systému běží aplikace jako PHP 3 (jako paralelně běžící modul Apache) nebo auth-mysql, používá jiné verze klientů MySQL, a je zde tedy konflikt dvou různých verzí těchto klientů.

Překompilování PHP 4 s přidáním cesty k MySQL do parametru, '--with-mysql=/your/path/to/mysql', obvykle tento problém vyřeší.

4. Po instalaci podpory sdíleného MySQL havaruje Apache v momentě, kdy načítá libphp4.so. Lze to vyřešit?

To se stává, když jsou knihovny MySQL připojovány s použitím pthreads. Ověřte to použitím "ldd". Pokud tomu tak je, stáhněte si balík MySQL a zkompilujte zdrojové soubory, nebo překompilujte soubory z RPM balíku a odstraňte přepínač, který zapíná threadový kód klienta. Jeden z těchto způsobů by měl problém vyřešit. Potom překompilujte PHP s novými knihovnami MySQL.

5. Proč dostávám chybu, která vypadá nějak takto: "Warning: 0 is not a MySQL result index in <file> on line <x>" nebo "Warning: Supplied argument is not a valid MySQL result resource in <file> on line <x>?

Pokoušíte se použít indentifikátor výsledku, který je 0. Nula indikuje, že váš dotaz z nějakého důvodu selhal. Po odeslání dotazu musíte provést kontrolu na chyby, dřív než se pokusíte použít vrácený indentifikátor výsledku. Správný způsob, jak to udělat, je popsán následujícím kódem:

$result = mysql_query("SELECT * FROM tables_priv"); if (!$result) { echo mysql_error(); exit; }
or

$result = mysql_query("SELECT * FROM tables_priv") or die("Bad query: ".mysql_error());

Kapitola 49. Instalace

Tato část se zabývá častými otázkamni ohledně způsobu instalace PHP. PHP je dostupné pro většinu OS (v podstatě kromě MacOS pře OSX) a většinu webovských serverů.

Při instalaci PHP postupujte podle instrukcí v souboru INSTALL v příslušné distribuci. Uživatelé Windows by si také měli přečíst soubor install.txt. Existuje také soubor s různými fintami pro Windows - najdete ho tady.

1. Unix/Windows: Kde by měl být uložen soubor php.ini?
2. UNIX: Nainstaloval jsem PHP, ale vždy, když načítám dokument, dostanu zprávu 'Document Contains No Data'! O co jde?
3. UNIX: Instaloval jsem PHP z balíčků RPM, ale Apache nezpracovává stránky s PHP! O co tu jde?
4. UNIX: Instaloval jsem PHP 3 z balíčků RPM, ale nekompiluje se s podporou databáze, kterou potřebuji! O co tu jde?
5. UNIX: Přidal jsem do Apache patch pro FrontPage Extension a PHP náhle přestalo pracovat. Je PHP nekompatibilní s FrontPage Extension pro Apache?
6. UNIX/Windows: Nainstaloval jsem PHP, ale při pokusu načíst soubor PHP skriptu do prohlížeče se zobrazí pouze prázdná obrazovka.
7. UNIX/Windows: Nainstaloval jsem PHP a když chci načíst PHP soubor do prohlížeče, objeví se "500 Internal Server Error".
8. Některé operační systémy: Nainstaloval jsem PHP bez chyb, ale nyní, když zkusím spustit Apache, ohlásí se chyby o nedefinovaných symbolech: [mybox:user /src/php4] root# apachectl configtest apachectl: /usr/local/apache/bin/httpd Undefined symbols: _compress _uncompress
9. Windows: Nainstaloval jsem PHP, ale při načtení stránky do prohlížeče se zobrazí chyba: cgi error: The specified CGI application misbehaved by not returning a complete set of HTTP headers. The headers it did return are:
10. Windows: Dodržel jsem všechny instrukce, ale PHP a IIS stále odmítají spolupracovat!

1. Unix/Windows: Kde by měl být uložen soubor php.ini?

V UNIXu má být implicitně v adresáři /usr/local/lib. Mnoho lidí to bude chtít při kompilaci změnit pomocí parametru --with-config-file-path. Mohli byste ho, například, nastavit zhruba takto:

--with-config-file-path=/etc
Pak byste zkopírovali soubor php.ini-dist z distribuce do /etc/php.ini a upravili tak, jak chcete.

Pod Windows je soubor php.ini implicintě umístěn v adresáři systému Windows.

2. UNIX: Nainstaloval jsem PHP, ale vždy, když načítám dokument, dostanu zprávu 'Document Contains No Data'! O co jde?

Pravděpobně to znamená, že PHP má nějaký problém a padá. Podívejte se do protokolu chyb, zda se jedná o tento případ a pak zkuste problém reprodukovat malým testem. Pokud víte, jak používat 'gdb', velmi pomůže, když můžete s vaším hlášením chyby poskytnout výpis (backtrace). Vývojáři tak mohou snadněji lokalizovat problém. Používáte-li PHP jako modul do serveru Apache, zkuste něco jako:

Zastavte httpd procesy
gdb httpd
Zastavte httpd procesy
> run -X -f /path/to/httpd.conf
Potom načtěte do prohlížeče URL, kde se vyskytl problém
> run -X -f /path/to/httpd.conf
Dostanete-li core dump (PHP spadne), gdb by vás o tom měl informovat
napište: bt
Získaný výpis (backtrace) byste měli přiložit k hlášení chyby. To by se mělo poslat na http://bugs.php.net/

Pokud váš skript používá funkce pro regulární výrazy (ereg() a další), měli byste se ujistit, že jste zkompilovali PHP a Apache se stejným balíčkem pro regulární výrazy. S PHP a Apachem 1.3.x by se to mělo dít automaticky.

3. UNIX: Instaloval jsem PHP z balíčků RPM, ale Apache nezpracovává stránky s PHP! O co tu jde?

Za předpokladu, že se obojí, jak Apache, tak PHP, instalovalo z balíčků RPM, bude třeba "odkomentovat" nebo přidat do souboru http.conf některé z následujících řádků (nebo všechny):

# Extra Modules AddModule mod_php.c AddModule mod_php3.c AddModule mod_perl.c # Extra Modules LoadModule php_module modules/mod_php.so LoadModule php3_module modules/libphp3.so /* pro PHP 3 */ LoadModule php4_module modules/libphp4.so /* pro PHP 4 */ LoadModule perl_module modules/libperl.so
Přidejte také:

AddType application/x-httpd-php3 .php3 /* pro PHP 3 */ AddType application/x-httpd-php .php /* pro PHP 4 */
... do globálních vlastností nebo do vlastností virtuální domény (VirtualDomain) by se měla přidat podpora PHP.

4. UNIX: Instaloval jsem PHP 3 z balíčků RPM, ale nekompiluje se s podporou databáze, kterou potřebuji! O co tu jde?

Kvůli tomu, jak se PHP 3 budovalo, není snadné sestavit kompletní flexibilní RPM balíček s PHP. Problém je vyřešen v PHP 4. Pro PHP 3 nyní doporučujeme používat mechanismus popsaný v souboru INSTALL.REDHAT v distribuci PHP. Pokud trváte na použití RPM verze PHP 3, čtěte dál...

RPM pakovače jsou nastaveny na tvorbu RPM balíčků k instalaci bez podpory databází kvůli zjednodušení instalací a proto, že RPM používá adresář /usr/ namísto standardního /usr/local/. Musít sdělit RPM souboru spec, které databáze podporovat a umístění adresáře nejvyšší úrovně databázového serveru.

Tento příklad vysvětluje proces přidání podpory populárního databázového serveru MySQL, pro instalaci PHP jako modulu do Apache.

Všechny tyto informace smaozřejmě mohou být upraveny pro libovolný databázový server, který PHP podporuje. Pro tento příklad budeme předpokládat, že jste instalovali MySQL a Apache plně z balíčků RPM.

Nejdříve odstraňte mod_php3 :
rpm -e mod_php3
Potom vezměte zdrojový balíček RPM a spusťte na něm, NE --rebuild
rpm -Uvh mod_php3-3.0.5-2.src.rpm

Upravte soubor /usr/src/redhat/SPECS/mod_php3.spec

V sekci %build přidejte databázovou podporu, kterou chcete, a nastavte cestu.

Pro MySQL byste přidali

--with-mysql=/usr \
Sekce %build bude vypadat přibližně takto:

./configure --prefix=/usr \ --with-apxs=/usr/sbin/apxs \ --with-config-file-path=/usr/lib \ --enable-debug=no \ --enable-safe-mode \ --with-exec-dir=/usr/bin \ --with-mysql=/usr \ --with-system-regex

Poté, co jsou provedeny tyto změny, zkompilujte balíček takto:
rpm -bb /usr/src/redhat/SPECS/mod_php3.spec

Potom balíček nainstalujte:

rpm -ivh /usr/src/redhat/RPMS/i386/mod_php3-3.0.5-2.i386.rpm

Ujistěte se, že jste restartovali Apache, a nyní již máte PHP 3 s podporou MySQL. Uvědomte si, že je pravděpodobně mnohem jednodušší zkompilovat distribuční balíček tar a držet se instrukcí v souboru INSTALL.REDHAT z distribuce.

5. UNIX: Přidal jsem do Apache patch pro FrontPage Extension a PHP náhle přestalo pracovat. Je PHP nekompatibilní s FrontPage Extension pro Apache?

Ne, PHP pracuje dobře i s FrontPage Extension. Problém je v tom, že FrontPage patch modifikuje některé struktury Apache, na které PHP spoléhá. Překompilování PHP (použitím 'make clean ; make') po instalaci FP patche by mělo problém vyřešit.

6. UNIX/Windows: Nainstaloval jsem PHP, ale při pokusu načíst soubor PHP skriptu do prohlížeče se zobrazí pouze prázdná obrazovka.

V prohlížeči vyberte funkci 'zobrazit zdrojový kód', nejspíš uvidíte zdrojový kód vašeho PHP skriptu. To znamená, že server neposílá skript k interpretaci. Chyba je někde v konfiguraci serveru - raději dvakrát zkontrolujte konfiguraci podle instrukcí k instalaci PHP.

7. UNIX/Windows: Nainstaloval jsem PHP a když chci načíst PHP soubor do prohlížeče, objeví se "500 Internal Server Error".

Při pokusu spustit PHP došlo k nějaké chybě. Abyste viděli detailnější chybovou zprávu, z příkazové řádky, přejděte do adresáře se souborem PHP (pod Windows php.exe) a spusťte php -i. Pokud při běhu PHP dojde k chybě, bude zobrazena odpovídající chybovou zpráva, která vám řekne, co se má dál udělat. Pokud získáte obrazovku plnou HTML kódu (výstup funkce phpinfo()), pak PHP funguje a váš problém může souviset s konfigurací serveru, kterou je pak třeba dobře zkontrolovat.

8. Některé operační systémy: Nainstaloval jsem PHP bez chyb, ale nyní, když zkusím spustit Apache, ohlásí se chyby o nedefinovaných symbolech:

[mybox:user /src/php4] root# apachectl configtest apachectl: /usr/local/apache/bin/httpd Undefined symbols: _compress _uncompress

To aktuálně nemá nic společného s PHP, ale s knihovnami klienta MySQL. Některé potřebují --with-zlib, jiné nikoli. Tímto se zabývá také MySQL FAQ.

9. Windows: Nainstaloval jsem PHP, ale při načtení stránky do prohlížeče se zobrazí chyba:

cgi error: The specified CGI application misbehaved by not returning a complete set of HTTP headers. The headers it did return are:

Tato chybová zpráva znamená, že z PHP nemohou vycházet žádná data. Abyste viděli detailnější chybovou zprávu, z příkazové řádky, přejděte do adresáře se souborem PHP (pod Windows php.exe) a spusťte php -i. Pokud při běhu PHP dojde k chybě, bude zobrazena odpovídající chybovou zpráva, která vám řekne, co se má dál udělat. Pokud získáte obrazovku plnou HTML kódu (výstup funkce phpinfo()), PHP funguje.

Jestliže PHP pracuje v příkazové řádce, zkuste to znovu z prohlížeče. Pokud to stále nefunguje, může to být jedním z těchto důvodů:

Nastavení přístupových práv k souboru se skriptem, k php.exe, php4ts.dll, php.ini nebo nějakému rozšíření PHP, které se pokoušíte načíst, je takové, že k nim anonymní internetový uživatel ISUR_<machinename> nemá přístup.
Soubor se skriptem neexistuje (nebo případně není tam, kde si myslíte, že je, relativně ke kořenovému adresáři webu). Uvědomte si, že na IIS můžete tuto chybu zachytit zaškrtnutím volby 'check file exists' při nastavování skriptových služeb v Internet Services Manageru. Pokud skript neexistuje, server vrátí chybu 404. Další výhodou je to, že IIS provede na souboru se skriptem všechny potřebné autentikace založené NTLanMan.

10. Windows: Dodržel jsem všechny instrukce, ale PHP a IIS stále odmítají spolupracovat!

Ujistěte se, že každý uživatel, který potřebuje spouštět PHP skripty má práva pro spouštění php.exe! IIS používá anonymního uživatele, který se přidá při instalaci IIS. Tento uživatel potřebuje práva k php.exe. Také každý autentikovaný uživatel bude potřebovat práva na spouštění php.exe. A IIS4 musíte sdělit, že PHP je skriptovací engine.

Kapitola 50. Sestavovací (kompilační) problémy

Tato sekce shrnuje nejčastější chyby, které se vyskytují při sestavování PHP.

1. Pomocí anonymního přístupu do CVS jsem získal poslední verzi PHP, ale chybí v ní skript "configure"!
2. Mám problém nakonfigurovat PHP tak, aby fungovalo se serverem Apache. Hlásí, že nemůže najít httpd.h, ale ten je přesně tam, kde jsem uvedl, že je!
3. Když spustím "configure", hlásí to, že nemůže najít "include" soubory nebo knihovny pro GD, gdbm a nějaké další balíky!
4. Když se kompiluje soubor language-parser.tab.c, hlásí to chyby, které říkají 'yytname undeclared'.
5. Když spustím "make", zdá se, že běží dobře, ale havaruje, když se pokouší sestavit konečnou aplikaci s hlášením, že nemůže najít nějaké soubory.
6. Při sestavování PHP to hlásí mnoho nedefinovaných referencí.
7. Nepřišel jsem na to, jak sestavit PHP pro Apache 1.3.
8. Postupoval jsem přesně podle instrukcí k instalaci PHP ve verzi jako modul pro Apache na UNIXu, a moje PHP skripty se zobrazují v prohlížeči nebo se je prohlížeč snaží uložit jako soubory.
9. Hlásí to použití --activate-module=src/modules/php4/libphp4.a, ale tento soubor neexistuje; proto jsem to změnil na --activate-module=src/modules/php4/libmodphp4.a a ono to nefunguje? O co jde?
10. Když zkusím sestavit Apache s PHP jakožto statickým modulem pomocí --activate-module=src/modules/php4/libphp4.a, hlásí to, že můj kompilátor nevyhovuje ANSI.
11. Když zkusím sestavit PHP s parametrem --with-apxs, dostanu záhadné chybové zprávy.
12. During 'make', I get errors in microtime, and a lot of 'RUSAGE_' stuff.
13. Chci upgradovat své PHP. Kde najdu tvar řádku ./configure, který byl použit pro sestavení stávající instalace PHP?

1. Pomocí anonymního přístupu do CVS jsem získal poslední verzi PHP, ale chybí v ní skript "configure"!

Musíte mít nainstalovaný balík "GNU autoconf", takže můžete vygenerovat skript "configure" z "configure.in". Po stažení zdrojových souborů z CVS serveru spusťte ./buildconf z nejvyšší adresářové úrovně (pokud nespustíte "configure" s parametrem --enable-maintainer-mode, skript "configure" nebude automaticky aktualizován při změně souboru "configure.in", takže se musíte ujistit, zda jste to udělali ručně poté, co byl "configure.in" změněn. Jedním z příznaků tohoto je nalezení elementů jako @VARIABLE@ v souboru "Makefile" potom, co byl spuštěn "configure" nebo "config.status").

2. Mám problém nakonfigurovat PHP tak, aby fungovalo se serverem Apache. Hlásí, že nemůže najít httpd.h, ale ten je přesně tam, kde jsem uvedl, že je!

Potřebujete sdělit konfiguračnímu/instalačnímu skriptu umístění nejvyšší úrovně zdrojových souborů Apache. To znamená, že specifikujete '--with-apache=/path/to/apache' a ne '--with-apache=/path/to/apache/src'.

3. Když spustím "configure", hlásí to, že nemůže najít "include" soubory nebo knihovny pro GD, gdbm a nějaké další balíky!

Můžete určit, aby skript "configure" hledal hlavičkové soubory a knihovny na nestandardních místech specifikací pomocných příznaků pro C preprocesor a linker, například:

CPPFLAGS=-I/path/to/include LDFLAGS=-L/path/to/library ./configure
Pokud používáte csh (C-shell) jako váš login shell (proč?), bylo by to:

env CPPFLAGS=-I/path/to/include LDFLAGS=-L/path/to/library ./configure

4. Když se kompiluje soubor language-parser.tab.c, hlásí to chyby, které říkají 'yytname undeclared'.

Musíte updatovat vaši verzi programu Bison. Nejnovější verzi najdete na ftp://ftp.gnu.org/pub/gnu/bison/.

5. Když spustím "make", zdá se, že běží dobře, ale havaruje, když se pokouší sestavit konečnou aplikaci s hlášením, že nemůže najít nějaké soubory.

Některé starší verze programu "make" neukládají korektně zkompilované verze souborů umístěných v adresáři funkcí do téhož adresáře. Zkuste spustit "cp *.o functions" a potom znovu 'make', abyste viděli, zda to pomohlo. Pokud ano, měli byste opravdu nainstalovat nejnovější verzi "GNU make".

6. Při sestavování PHP to hlásí mnoho nedefinovaných referencí.

Podívejte se do řádku, kde je popsáno sestavování a ujistěte se, že byly přidány na konec všechny potřebné knihovny. Často se stává, že chybí '-ldl' a některé knihovny potřebné pro podporu databáze, kterou jste určili.

Pokud sestavujete pro Apache 1.2.x, nezapomněli jste přidat odpovídající informace na řádek EXTRA_LIBS v souboru "configure" a spustit skript pro konfiguraci Apache? Pro více informací se podívejte do souboru INSTALL, který získáte s distribučním balíkem.

Někteří lidé také hlásili, že pokud sestavovali pro Apache, museli přidat '-ldl' těsně za 'libphp4.a'.

7. Nepřišel jsem na to, jak sestavit PHP pro Apache 1.3.

Toto je nyní velmi snadné. Následujte pečlivě tyto kroky:

Stáhněte nejnovější distribuci Apache 1.3 z http://www.apache.org/dist/.
Rozbalte ji někam, například do /usr/local/src/apache-1.3.
Zkompilujte PHP nejdříve spuštěním ./configure --with-apache=/<path>/apache-1.3 (nahraďte <path> aktuální cestou k adresáři apache-1.3).
Napište 'make' a potom 'make install' k sestavení PHP a zkopírování potřebných souborů do distribučního stromu Apache.
Změňte adresář na /<path>/apache-1.3/src a upravte soubor Configuration. Do souboru přidejte: AddModule modules/php4/libphp4.a.
Spusťte './Configure' a potom 'make'.
Nyní byste měli míst hotové soubory httpd pro práci s PHP.

Poznámka: : Můžete použít také nový skript ./configure pro Apache. Přečtěte si instrukce v README.configure, který je v distribuci Apache. Nahlédněte také do souboru INSTALL z distribuce PHP.

8. Postupoval jsem přesně podle instrukcí k instalaci PHP ve verzi jako modul pro Apache na UNIXu, a moje PHP skripty se zobrazují v prohlížeči nebo se je prohlížeč snaží uložit jako soubory.

To znamená, že PHP modul není z nějakých důvodů vyvoláván. Dříve, než budete shánět další pomoc, zkontrolujte tři věci:

Ujistěte se, že se spouští právě ten httpd, který jste zkompilovali. Zkuste spustit /path/to/binary/httpd -l

Pokud v seznamu neuvidíte mod_php4.c, potom nespouštíte správnou verzi httpd. Najděte s instalujte správnou verzi.
Ujistěte se, že jste přidali správnou specifikaci Mime Type do souborů .confpro Apache. Mělo by tam být: AddType application/x-httpd-php3 .php3 (pro PHP 3)

nebo AddType application/x-httpd-php .php (pro PHP 4)

Také se ujistěte, že tento řádek AddType není ukryt uvnitř bloku <Virtualhost> nebo <Directory>, což může zabránit aplikaci pravidla na oblast, kde je umístěn testovací skript.
Konečně, implicitní umístění konfiguračních souborů Apache se mezi verzemi Apache 1.2 a 1.3 změnilo. Měli byste ověřit, že soubor, do kterého jste přidali řádek AddType je ten, který je skutečně načítán. Můžete zkusit vložit nějakou příšernou syntaktickou chybu do souboru httpd.conf nebo udělat nějakou jinou změnu tohoto rázu - uvidíte, zda je soubor správně načítán.

9. Hlásí to použití --activate-module=src/modules/php4/libphp4.a, ale tento soubor neexistuje; proto jsem to změnil na --activate-module=src/modules/php4/libmodphp4.a a ono to nefunguje? O co jde?

Uvědomte si, že soubor libphp4.a nemá existovat. Vytváří ho proces serveru Apache!

10. Když zkusím sestavit Apache s PHP jakožto statickým modulem pomocí --activate-module=src/modules/php4/libphp4.a, hlásí to, že můj kompilátor nevyhovuje ANSI.

Toto je zavádějící chybové hlášení, které bylo odstraněno v pozdějších verzích.

11. Když zkusím sestavit PHP s parametrem --with-apxs, dostanu záhadné chybové zprávy.

Je třeba zkontrolovat tři věci. Nejdříve, z důvodu, že když Apache vytváří apxs skript v Perlu, někdy ukončí kompilaci bez odpovídajících proměnných. Najděte skript apxs (zkuste příkaz 'which apxs', někdy bývá v /usr/local/apache/bin/apxs nebo /usr/sbin/apxs). Otevřte ho a zkontrolujte řádky podobné těmto:

my $CFG_CFLAGS_SHLIB = ' '; # nahrazeno pomocí Makefile.tmpl my $CFG_LD_SHLIB = ' '; # nahrazeno pomocí Makefile.tmpl my $CFG_LDFLAGS_SHLIB = ' '; # nahrazeno pomocí Makefile.tmpl
Pokud vidíte toto, našli jste ten problém. Mohou se tam vyskytovat mezery nebo jiné nekorektní hodnoty, např. 'q()'. Změňte řádky takto:

my $CFG_CFLAGS_SHLIB = '-fpic -DSHARED_MODULE'; # substituted via Makefile.tmpl my $CFG_LD_SHLIB = 'gcc'; # nahrazeno pomocí Makefile.tmpl my $CFG_LDFLAGS_SHLIB = q(-shared); # nahrazeno pomocí Makefile.tmpl
Druhý možný problém by měl vyskytovat pouze na Red Hat Linuxu 6.1 a 6.2. Skript apxs v těchto distribucích Red Hat je poškozený. Najděte řádek

my $CFG_LIBEXECDIR = 'modules'; # nahrazeno pomocí APACI install
Pokud vidíte výše uvedený řádek, nahraďte ho tímto:

my $CFG_LIBEXECDIR = '/usr/lib/apache'; # nahrazeno pomocí APACI install
Nakonec, když budete přeinstalovávat Apache, zařaďte 'make clean' mezi './configure' a 'make'.

12. During 'make', I get errors in microtime, and a lot of 'RUSAGE_' stuff.

During the 'make' portion of installation, if you encounter problems that look similar to this:

microtime.c: In function `php_if_getrusage': microtime.c:94: storage size of `usg' isn't known microtime.c:97: `RUSAGE_SELF' undeclared (first use in this function) microtime.c:97: (Each undeclared identifier is reported only once microtime.c:97: for each function it appears in.) microtime.c:103: `RUSAGE_CHILDREN' undeclared (first use in this function) make[3]: *** [microtime.lo] Error 1 make[3]: Leaving directory `/home/master/php-4.0.1/ext/standard' make[2]: *** [all-recursive] Error 1 make[2]: Leaving directory `/home/master/php-4.0.1/ext/standard' make[1]: *** [all-recursive] Error 1 make[1]: Leaving directory `/home/master/php-4.0.1/ext' make: *** [all-recursive] Error 1

Váš systém je poškozen. Musíte opravit soubory v /usr/include instalací balíku glibc-devel, který patří k vašemu glibc. Nemá to absolutně nic společného s PHP. Důkaz získáte tímto jednoduchým testem:

$ cat >test.c <<X #include <sys/resource.h> X $ gcc -E test.c >/dev/null
Pokud se objeví chyby, ve vašich hlavičkových souborech panuje chaos.

13. Chci upgradovat své PHP. Kde najdu tvar řádku ./configure, který byl použit pro sestavení stávající instalace PHP?

Když se podíváte do souboru config.nice ve zdrojovém stromu současné instalace PHP. Není-li k dispozici, jednoduše spusťte skript

Nahoře ve výpisu najdete řádek ./configure, který byl použit při sestavování stávající instalace.

Kapitola 51. Používání PHP

Tato část shrnuje nejčastější chyby, se kterými se můžete setkat při psaní PHP skriptů.

1. Chtěl bych napsat generický PHP skript, který by uměl zpracovat data z jakéhokoli formuláře. Jak se dozvím, které proměnné metody POST jsou k dispozici?
2. Potřebuji převést všechny apostrofy (') na zpětná lomítka následovaná apostrofy. Jak se to dá udělat pomocí regulárního výrazu?
3. Když napíšu následující kód, výstup se tiskne v nesprávném pořadí: function myfunc($argument) { echo $argument + 10; } $variable = 10; echo "myfunc($variable) = " . myfunc($variable); what's going on?
4. Hej, co se stalo s mými konci řádků? <pre> <?php echo "Tohle by měl být první řádek."; ?> <?php echo "Tohle by se mělo ukázat na novém řádku."; ?> </pre>
5. Zobrazila se mi zpráva 'Warning: Cannot send session cookie - headers already sent...' nebo 'Cannot add header information - headers already sent...'.
6. Potřebuji přímo přistupovat k hlavičce požadavku. Jak to udělat?
7. Když zkusím autentikaci s IIS, dostanu 'No Input file specified'.
8. Můj PHP skript pracuje na IE a Lynxu, ale v Netscapu část výstupu mizí. Když si zapnu "Zobrazit zdrojový kód", v IE vidím obsah, v Netscapu nikoliv.
9. Jaké jsou předpoklady míchání XML a PHP? Stěžuje si to na moje <?xml> tagy!
10. Jak mohu použít PHP s FrontPagem nebo jiným HTML editorem, který trvá na odsunutí mého kódu?
11. Kde najdi úplný seznam dostupných přednastavených proměnných, a proč to není zdokumentováno v dokumentaci PHP?
12. Zkouším přistupovat k jedné ze standardních CGI proměnných (jako je $DOCUMENT_ROOT nebo $HTTP_REFERER) v uživatelsky definované funkci, a nemůže ji to najít. Co je špatně?

1. Chtěl bych napsat generický PHP skript, který by uměl zpracovat data z jakéhokoli formuláře. Jak se dozvím, které proměnné metody POST jsou k dispozici?

Ujistěte se, že máte v souboru php.ini zapnuto track_vars Od PHP 4.0.3 je tato možnost vždy zapnuta. Pokud tomu tak je, vytvoří se nějaká asociativní pole, z nichž nejdůležitější je $HTTP_POST_VARS. Takže pro psaní generického skriptu pro obsluhu proměnných metody POST budete potřebovat přibližně toto:

foreach ($HTTP_POST_VARS as $var => $value) { echo "$var = $value<br>\n"; }

2. Potřebuji převést všechny apostrofy (') na zpětná lomítka následovaná apostrofy. Jak se to dá udělat pomocí regulárního výrazu?

Nejdříve se podívejte na funkci addslashes(). Dělá přesně to, co potřebujete. Měli byste se také podívat na direktivu magic_quotes_gpc v souboru php.ini.

3. Když napíšu následující kód, výstup se tiskne v nesprávném pořadí:

function myfunc($argument) { echo $argument + 10; } $variable = 10; echo "myfunc($variable) = " . myfunc($variable);
what's going on?

Pro použití výsledků vaší funkce ve výrazu (jako je spojení s jiným řetězcem v příkladu výše), musíte hodnotu vracet (pomocí vracet), ne tisknout() (pomocí echo()).

4. Hej, co se stalo s mými konci řádků?

<pre> <?php echo "Tohle by měl být první řádek."; ?> <?php echo "Tohle by se mělo ukázat na novém řádku."; ?> </pre>

V PHP se blok kódu zakončuje buď "?>", nebo "?>\n" (kde \n znamená nový řádek). Takže ve výše uvedeném příkladu budou vypsané věty na jediném řádku, protože PHP vynechává konce řádků za koncem bloku. To znamená, že musíte přidávat zvláštní konce řádků za každý blok PHP kódu, aby se vytisklo odřádkování jediné.

Proč to PHP dělá? Při formátování normálního HTML to obvykle zjednodušuje život, protože nechcete konce řádků, nýbrž chcete vytvořit extrémně dlouhé řádky nebo jinak znečitelnit zdrojový kód.

5. Zobrazila se mi zpráva 'Warning: Cannot send session cookie - headers already sent...' nebo 'Cannot add header information - headers already sent...'.

Funkce header(), set_cookie() a funkce session musí do výstupu přidat hlavičky. Hlavičky je možno posílat pouze před vlastním obsahem. Funkce to udělají, pokud PHP běží jako modul Apache. Následující kus kódu zobrazí všechny hlavičky v požadavku:

$headers = getallheaders(); foreach ($headers as $name => $content) { echo "headers[$name] = $content<br>\n"; }

6. Potřebuji přímo přistupovat k hlavičce požadavku. Jak to udělat?

Funkce getallheaders() to udělá, pokud PHP běží jako modul do Apache. Následující kus kódu zobrazí všechny hlavičky v požadavku:

$headers = getallheaders(); foreach ($headers as $name => $content) { echo "headers[$name] = $content<br>\n"; }

7. Když zkusím autentikaci s IIS, dostanu 'No Input file specified'.

Bezpečnostní model IIS je s tím na štíru. Je to problém společný všem CGI programům běžícím pod IIS. Řešením je vytvořit obyčejný HTML soubor (neparsovaný PHP) jako vstupní stránku do autentikovaného adresáře. Potom se použije META tag k přesměrování na PHP stránku nebo odkaz k ručnímu přechodu. PHP pak autentikaci zpracuje správně. S modulem ISAPI toto není problémem. Jiných NT webovských serverů se problém netýká. Více informací - viz http://support.microsoft.com/support/kb/articles/q160/4/22.asp.

8. Můj PHP skript pracuje na IE a Lynxu, ale v Netscapu část výstupu mizí. Když si zapnu "Zobrazit zdrojový kód", v IE vidím obsah, v Netscapu nikoliv.

Netscape je striktnější ohledně HTML tagů (např. tabulek) něž IE. Kontrola HTML výstupu pomocí HTML validátoru, jako je validator.w3.org, může být nápomocna. Například chybějící </table> způsobuje výše uvedený problém.

IE i Lynx také ignorují jakékoliv nulové (\0) znaky v HTML proudu, Netscape nikoli. Nejlepší cestou k ověření je zkompilovat verzi PHP pro příkazovou řádku (známou jako CGI verze) a spustit skript z příkazové řádky. Na *NIXech to přesměrujte do od -c a hledejte znaky \0. Pod Windows musíte najít editor nebo jiný program, který umožňuje prohlížení binárních souborů. Když Netscape uvidí v souboru nulový znak, typicky nic dalšího nezobrazí, ačkoli IE i Lynx ano.

9. Jaké jsou předpoklady míchání XML a PHP? Stěžuje si to na moje <?xml> tagy!

Musíte vypnout krátké tagy v souboru php.ini nastavením short_tags na 0 nebo použitím odpovídající direktivy Apache. Můžete také použít sekci <File> k selektivnímu nastavení.

10. Jak mohu použít PHP s FrontPagem nebo jiným HTML editorem, který trvá na odsunutí mého kódu?

Jedním z nejjednodušších způsobů je povolit použití ASP tagů v PHP kódu. To umožní používat oddělovače v ASP stylu (<% a %>). Některé populární HTML editory s pracují (v tuto chvíli) inteligentněji. K zapnutí ASP tagů musíte v souboru php.ini nastavit proměnnou asp_tags nebo použít příslušnou direktivu Apache.

11. Kde najdi úplný seznam dostupných přednastavených proměnných, a proč to není zdokumentováno v dokumentaci PHP?

Nejlepší metodou je vložit do stránky <?php phpinfo(); ?> a načíst to do prohlížeče. Zobrazí se informace všeho druhu o nainstalovaném PHP, včetně seznamu proměnných prostředí i speciálních proměnných nastavovaných HTTP serverem. Tento seznam opravdu nemůže být zdokumentován v dokumentaci k PHP, protže se liší server od serveru.

12. Zkouším přistupovat k jedné ze standardních CGI proměnných (jako je $DOCUMENT_ROOT nebo $HTTP_REFERER) v uživatelsky definované funkci, a nemůže ji to najít. Co je špatně?

Proměnné prostředí jsou normální globální proměnné, takže je musíte buď deklarovat ve funkci jako globální proměnné (například použitím "global $DOCUMENT_ROOT;") nebo použít pole globálních proměnných (např. "$GLOBALS["DOCUMENT_ROOT"]").

Kapitola 52. PHP a HTML

PHP a HTML mají hodně společného: PHP generuje HTML, a HTML má informace, které budou poslány PHP.

1. Jaké zakódování/dekódování potřebuji, když posílám hodnotu přes formulář? A v URL?
2. Zkouším použít tag <input type="image">, ale proměnné $foo.x a $foo.y nejsou dostupné. Kde jsou?
3. Jak vytvořím pole ("array") v HTML formuláři?
4. Jak získám všechna data z HTML elementu pro vícenásobný výběr?

1. Jaké zakódování/dekódování potřebuji, když posílám hodnotu přes formulář? A v URL?

Je více situací, pro které je zakódování důležité. Za předpokladu, že máte string $data, který obsahuje řetězec, jenž máte nezakódovaný a chcete ho poslat, je třeba se zabývat těmito relevantními problémy:

HTML interpretace. Pokud specifikujete náhodný (obecný) řetězec, musíte ho dát do uvozovek a celý ho zpracovat funkcí htmlspecialchars() (aby se odstranily/převedly speciální znaky jazyka HTML).
URL: sestává z několika částí. Pokud chcete, aby vaše data byla interpretována jako jedna položka, musíte je zakódovat pomocí urlencode().

Příklad 52-1. Skrytý element HTML formuláře

<?php echo "<input type=hidden value=\"" . htmlspecialchars($data) . "\">\n"; ?>

Poznámka: Je chybou použít urlencode() pro $data, protože prohlížeče samy zajišťují zpracování dat shodné s funkcí urlencode(). Všechny oblíbené prohlížeče to dělají korektně. Uvědomte si, že toto není závislé na použité metodě (např. GET nebo POST). Všimnete si toho však pouze v případě GET, protože požadavky POST jsou obvykle skryté.

Příklad 52-2. Data k editaci uživatelem

<?php
    echo "<textarea name=mydata>\n";
    echo htmlspecialchars($data)."\n";
    echo "</textarea>";
?>

Poznámka: Data jsou v prohlížeči zobrazena tak, jak bylo zamýšleno, protože prohlížeč bude správně interpretovat speciální symboly.

Po odeslání, ať již pomocí GET nebo POST, data budou zakódována způsobem urlencode pro přenos a následně přímo dekódována v PHP. Takže vůbec nepotřebujete provádět žádné zakódování/dekódování ručně, vše je prováděno automaticky.

Příklad 52-3. Uvnitř URL

<?php
    echo "<a href=\"" . htmlspecialchars("/nexpage.php?stage=23&data=" .
        urlencode($data)) . "\">\n";
?>

Poznámka: V tomto případě již opravdu vytváříte GET požadavek, proto je nutné data kódovat ručně pomocí urlencode().

Poznámka: Musíte také použít htmlspecialchars() na celý URL, protože URL je zde hodnotou HTML atributu. V tomto případě prohlížeč nejdříve odstraní speciální znaky a pak zpracuje URL. PHP správně pochopí posílaný URL, protože jste data zakódovali pomocí urlencoded().

Můžete se všimnout, že symbol & v URL je nahrazen &. Přestože to většina prohlížečů opraví. pokud na to zapomenete, není to vždy možné. Takže pokud váš URL není dynamický, musíte použít htmlspecialchars().

2. Zkouším použít tag <input type="image">, ale proměnné $foo.x a $foo.y nejsou dostupné. Kde jsou?

Když odesíláte formulář, lze namísto standardního tlačítka použít obrázek pomocí tagu jako

<input type="image" src="image.gif" name="foo">
Když uživatel klikne někde na obrázku, příslušný formulář se odešle na server s dvěma proměnnými navíc: foo.x a foo.y.

Protože $foo.x a $foo.y jsou v PHP neplatné názvy proměnných, jsou automaticky převedeny na $foo_x a $foo_y. Tzn. tečky jsou nahrazeny podtržítky.

3. Jak vytvořím pole ("array") v HTML formuláři?

Aby výsledky odeslání vašeho formuláře byly umístěny v poli (array), nazvěte elementy <input>, <select> nebo <textarea> tímto způsobem:

<input name="MyArray[]"> <input name="MyArray[]"> <input name="MyArray[]"> <input name="MyArray[]">
Všimněte si hranatých závorek po názvu proměnné, to je to, co z toho dělá pole. Můžete seskupovat elementy do různých polí spojením stejného jména s různými elementy:

<input name="MyArray[]"> <input name="MyArray[]"> <input name="MyOtherArray[]"> <input name="MyOtherArray[]">
Toto produkuje dvě pole, MyArray a MyOtherArray, která budou zaslána PHP skriptu. Je také možné dát do polí specifické klíče:

<input name="AnotherArray[]"> <input name="AnotherArray[]"> <input name="AnotherArray[email]"> <input name="AnotherArray[phone]">
Pole AnotherArray bude nyní obsahovat klíče 0, 1, email a phone.

Poznámka: Specifikace klíců polí je v HTML nepovinné. Pokud klíče nespecifikujete, pole bude vyplněno podle pořadí elementů ve formuláři. Náš první příklad obsahuje klíče 0, 1, 2 a 3.

Viz také Funkce pro práci s poli a Proměnné z vnějšku PHP.

4. Jak získám všechna data z HTML elementu pro vícenásobný výběr?

Tag pro vícenásobný výběr v HTML konstruktu umožňuje uživatelům vybrat více položej ze seznamu. Tyto položky se posílají do handleru pro formulář. Problém je v tom, že se zpracovávají pod stejným jménem. Například:

<select name="var" multiple>
Každá vybraná možnost přijde do handleru akce jako:

var=option1 var=option2 var=option3
Každá volba tedy přepíše předchozí obsah proměnné $var Řešením je použít "pole vytvořené v elementu formuláře". Mělo by se použít toto:

<select name="var[]" multiple>
Výše uvedený kód říká PHP, že má proměnnou $var zpracovat jako pole a každé přiřazení hodnoty do var[] znamená přidání prvku do pole. První položka se tedy stane prvkem $var[0], další $var[1] atd. Funkci count() lze použít k určení, kolik možností bylo vybráno, a v případě potřeby lze seřadit pole funkcí sort().

Uvědomte si, že pokud používáte JavaScript, může přidání [] do názvu elementu způsobit problémy při pokusu odkazovat element jeho jménem. Tehdy použijte číselnou identifikaci elementu, nebo název proměnné uzavřete do apostrofů a použijte ho jako indexaci do pole elementů, například:

variable = documents.forms[0].elements['var[]'];

Kapitola 53. PHP a COM

PHP lze na platformách Win32 použít k přístupu k objektům COM a DCOM.

1. Zkompiloval jsem knihovnu DLL k nějakým výpočtům. Existuje způsob, jak tuto knihovnu spustit pod PHP?
2. Co znamená 'Unsupported variant type: xxxx (0xxxxx)'?
3. Je možné v PHP manipulovat vizuálními objekty?
4. Mohu ukládat COM objekty do session?
5. Jak mohu zachycovat chyby COM?
6. Mohu generovat knihovny DLL z PHP skriptů, podobně jako v Perlu?
7. Co znamená 'Unable to obtain IDispatch interface for CLSID {xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}'?
8. Jak lze spustit objekt COM ze vzdáleného serveru?
9. Zobrazilo se 'DCOM is disabled in C:\path...\scriptname.php on line 6', co mám dělat?
10. Lze načíst objekt ActiveX na stránce, resp. s ním manipulovat, pomocí PHP?
11. Je možné získat běžící instanci komponenty?
12. Existuje způsob, jak obsloužit událost odeslanou z objektu COM?
13. Mám problémy, když se pokouším vyvolat metodu objektu COM, která vystavuje více než jeden interface. Co mám dělat?
14. Když PHP pracuje s COM, jak je to s COM+?
15. Jestliže může PHP manipulovat s objekty COM, lze si představit použití MTS ke správě prostředků komponent společně s PHP?

1. Zkompiloval jsem knihovnu DLL k nějakým výpočtům. Existuje způsob, jak tuto knihovnu spustit pod PHP?

Pokud je to jednoduchá DLL knihovna, zatím ji není možné spustit z PHP. Pokud však tato knihovna obsahuje COM server, můžete k ní přistupovat, pokud implementuje interface IDispatch.

2. Co znamená 'Unsupported variant type: xxxx (0xxxxx)'?

Existují tucty typů VARIANT a jejich kombinací. Většina z nich je již podporována, ale několik z nich teprve musí být implementováno. Pole nejsou podporována plně. Mezi PHP a COM lze vyměňovat pouze jednorozměrná indexovaná pole. Pokud najdete jiné typy, které nejsou podporovány, ohlašte je prosím jako chybu - bug (pokud již nebyly ohlášeny) a poskytněte o nich tolik informací, kolik můžete.

3. Je možné v PHP manipulovat vizuálními objekty?

Obecně je, ale protože PHP se nejčastěji používá jako webovský skriptovací jazyk, běží v prostředí WWW serveru, a proto se vizuální objekty nezobrazují na ploše displeje serveru. Pokud používáte PHP pro aplikační skriptování, např. společně s PHP-GTK, neexistuje omezení přístupu a manipulace s vizuálními objekty pomocí COM.

4. Mohu ukládat COM objekty do session?

Nemůžete. S instancemi COM se nakládá jako s prostředky a proto jsou k dispozici pouze v kontextu jediného skriptu.

5. Jak mohu zachycovat chyby COM?

Momentálně není možné zachycovat chyby COM kromě způsobů poskytovaných samotným PHP (@, track_errors, ...), nicméně přemýšlíme o způsobu, jak to implementovat.

6. Mohu generovat knihovny DLL z PHP skriptů, podobně jako v Perlu?

Ne, v PHP bohužel není takový nástroj k dispozici.

7. Co znamená 'Unable to obtain IDispatch interface for CLSID {xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}'?

Tato chyba může mít více příčin:

hodnota CLSID je chybná
chybí požadovaná DLL knihovna
požadovaná komponenta neimplementuje interface IDispatch

8. Jak lze spustit objekt COM ze vzdáleného serveru?

Přesně tak, jak spouštíte místní objekty. Musíte pouze použít IP adresu vzdáleného stroje jako druhý parametr konstruktoru COM.

Ujistěte se, že je nastaveno com.allow_dcom=true v souboru php.ini.

9. Zobrazilo se 'DCOM is disabled in C:\path...\scriptname.php on line 6', co mám dělat?

Upravte soubor php.ini - nastavte tam com.allow_dcom=true.

10. Lze načíst objekt ActiveX na stránce, resp. s ním manipulovat, pomocí PHP?

To nemá s PHP nic společného. Objekty ActiveX se načítají na straně klienta, pokud jsou vyžádány HTML dokumentem. Nemá to žádnou souvislost s PHP skriptem a proto není možná žádná přímá interakce na straně serveru.

11. Je možné získat běžící instanci komponenty?

Je to možné pomocí "monikerů". Pokud chcete získat více referencí na tutéž instanci, můžete vytvořit tuto instanci tímto způsobem:

$word = new COM("C:\docs\word.doc");

Toto vytvoří novou instanci, pokud není k dispozici žádná běžící instance, resp. vrátí handle na běžící instanci.

12. Existuje způsob, jak obsloužit událost odeslanou z objektu COM?

Zatím ne.

13. Mám problémy, když se pokouším vyvolat metodu objektu COM, která vystavuje více než jeden interface. Co mám dělat?

Odpověď je stejně tak jednoduchá, jako neuspokojivá. Nelze to říci přesně, ale asi nemůžete dělat nic. Pokud má někdo specifické informace o tomto problému, ať laskavě napíše sem.

14. Když PHP pracuje s COM, jak je to s COM+?

COM+ rozšiřuje COM rámec pro správu komponent přes MTS a MSMQ, ale není to nic zvláštního na to, aby PHP muselo takové komponenty podporovat.

15. Jestliže může PHP manipulovat s objekty COM, lze si představit použití MTS ke správě prostředků komponent společně s PHP?

PHP samotné nemůže zatím obsluhovat transakce. Proto když nastane chyba, není iniciován žádný rollback. Pokud používáte komponenty, které podporují transakce, budete muset implementovat vlastní mechanismus správy transakcí.

Kapitola 54. PHP a jiné jazyky

PHP je nejlepší jazyk pro webové programování, ale co jiné jazyky?

1. PHP vs. ASP?
2. Existuje konvertot z ASP do PHP?
3. PHP vs. Cold Fusion?
4. PHP vs. Perl?

1. PHP vs. ASP?

ASP ve skutečnosti není jazyk jako takový, je to zkratka pro Active Server Pages, jazyky nyní používanými k programování ASP jsou Visual Basic Script a JScript. Největší nevýhodou ASP je to, že se jedná o proprietární systém, který je nativně používán pouze na serveru Microsoft Internet Information Server (IIS). To omezuje jeho dostupnost na servery založené na Win32. Existuje několik projektů, které umožňují běh ASP v jiných prostředích a serverech: InstantASP od Halcyon (komerční), Chili!Soft ASP od Chili!Soft (komerční) a OpenASP od ActiveScripting.org (free). O ASP se tvrdí, že je pomalejší a těžkopádnější, a stejně tak i méně stabilní. Z výhod ASP lze uvést to, že primárně používá VBScript, který je poměrně snadno uchopitelný, pokud již víte, jak programovat ve Visual Basicu. Podpora ASP je také standardně zapnuta na IIS, takže se snadno spustí a běží. Komponenty zabudované v ASP jsou opravdu omezené, takže pokud potřebujete použít "pokročilé" prvky, jako interakce s FTP servery, musíte si koupit doplňující komponenty.

2. Existuje konvertot z ASP do PHP?

Ano, jedním z nejčastěji zmiňovaných je asp2php.

3. PHP vs. Cold Fusion?

O PHP se často tvrdí, že je rychlejší a efektivnější pro složité programové úlohy a zkoušení nových myšlenek. PHP je obecně zmiňováno jako stabilnější a méně náročné na systémové prostředky. Cold Fusion má lepší zpracování chyb, databázovou abstrakci a parsování dat, ačkoliv databázová abstrakce je addressed in PHP 4. Jinou věcí, která je uváděna jako silný nástroj Cold Fusion, je jeho výborný vyhledávací engine, avšak s tím, že vyhledávací engine není něco, co by mělo být součástí skriptovacího jazyka pro web. PHP běží na většině existujících platforem; Cold Fusion je k dispozici pouze na Win32, Solarisu, Linuxu a HP/UX. Cold Fusion má dobré IDE a je obecně jednodušší pro začátky, zatímco PHP vyžaduje více programátorských znalostí. Produkt Cold Fusion je navržen s ohledem na neprogramátory, PHP je naopak zaměřeno na programátory.

Velký souhrn na toto téma od Michaela J. Sheldona bylo posláno do mailové konfernce PHP. Kopii najdete ¨zde.

4. PHP vs. Perl?

Největší výhodou PHP oproti Perlu je, že PHP bylo navrženo pro skriptování pro web, kdežto cílem Perlu bylo dělat mnohem víc věcí, a může proto být velmi komplikovaný. Flexibilita/složitost Perlu usnadňuje napsání kódu, který bude pro jiného autora těžko čitelný. PHP má méně zmatečný a striktnější formát beze ztráty flexibility. PHP je oproti Perlu jednodušší integrovat do existujícího HTML kódu. PHP obsahuje mnoho z "dobré" funkcionality Perlu: konstrukty, syntaxi apod., bez komplikovanosti, kterou může Perl přinést. Perl je dobře vyzkoušený a "opravdový jazyk", byl k dispozici již na konci 80. let, ale PHP rychle dospívá.

Kapitola 55. Přechod z PHP 2 na PHP 3

PHP má již za sebou dlouhou historii: Legendární PHP 1.0, PHP/FI, PHP 3.0 a PHP 4.0.

1. Přechod z PHP 2 na PHP 3?

1. Přechod z PHP 2 na PHP 3?

PHP/FI 2.0 již není podporováno. Podívejte se prosím do odpovídající části manuálu, kde najdete informace o přechodu z PHP/FI 2.0.

Pokud stále používáte PHP 2, vřele vám doporučujeme upgradovat přímo na PHP 4.

Kapitola 56. Přechod z PHP 3 na PHP 4

PHP má již za sebou dlouhou historii: Legendární PHP 1.0, PHP/FI, PHP 3.0 a PHP 4.0.

1. Přechod z PHP3 na PHP4
2. Nekompatibilní funkce?

1. Přechod z PHP3 na PHP4

PHP 4 bylo navrženo tak, aby bylo tak kompatibilní se staršími verzemi, jak je to jen možné, a přitom se ztratila troška funkčnosti. Pokud jste opravdu nejistí ohledně kompatibility, měli byste nainstalovat PHP 4 do testovacího prostředí a spouštět skripty tam.

Viz také příslušný dodatek tohoto manuálu.

2. Nekompatibilní funkce?

Přestože je PHP 4 kompletně přepsaný PHP engine, je jen velmi málo funkcí, která se změnily a to pouze ty exotičtější.

Kapitola 57. Ostatní otázky

Mohou existovat otázky, které nemůžeme umístit do žádné jiné kategorie. Najdete je zde.

1. Co se stalo s vyskakovacími okny na webovské stránce? Mohu získat takový kód?
2. Mohu s manuály komprimovanými pomocí bz2 pracovat ve Windows?

1. Co se stalo s vyskakovacími okny na webovské stránce? Mohu získat takový kód?

Žlutá vyskakovací okna na starých stránkách byla opravdu "dost dobrá", ale velmi složitá na údržbu (hlavně, když se zdá, že se některé firmy vyžívají ve změnách způsobu práce každé npvé verze prohlížeče).

Veškerý kód předchozích verzí stránek je stále dostupný přes CVS. Navíc, poslední verze shared.inc (obsahuje všechen JavaScript a DHTML pro vyskakovací okna) je k dispozici tady.

2. Mohu s manuály komprimovanými pomocí bz2 pracovat ve Windows?

Pokud nemáte archivační nástroj pro práci se soubory bz2, stáhněte si nástroj pro příkazovou řádku od RedHatu. Uživatelé Win2k SP2 ať si stáhnou nejnovější verzi 1.0.2, uživatelé ostatních systémů Windows by si měli stáhnout verzi 1.00. Po stažení přejmenujte spustitelný soubor na bzip2.exe. Je výhodné přesunout ho do adresáře v nastavení cest, např. C:\Windows (kde C představuje disk, kde jsou nainstalovány Windows).

Pozn.: "lang" představuje váš jazyk a "x" zvolený formát, např. pdf. K rozbalení souboru php_manual_lang.x.bz2 postupujte podle těchto kroků:

otevřte okno příkazové řádky
přejděte do složky, kde je uložen stažený soubor php_manual_lang.x.bz2
spusťte bzip2 -d php_manual_lang.x.bz2, rozbalí php_manual_lang.x do téže složky

V případě, že jste stáhli php_manual_lang.tar.bz2 obsahující v sobě více HTML souborů, je procedura stejná. Jediný rozdíl je ten, že obdržíte soubor php_manual_lang.tar. O formátu tar je známo, že ho lze zpracovat běžnými archivačními programy na Windows, jako je WinZip.

Pokud byste nechtěli používat nástroj pro příkazovou řádku, můžete zkusit free software Stuffit Expander dostupný pro jakýkoliv operační systém. Máte-li WinRAR, můžete s ním také snadno dekomprimovat bz2 soubory. Pokud používáte Windows Commander, plugin pro bz2 je k dispozici zdarma přímo na stránce programu Windows Commander.

VII. Dodatky

Obsah
A. Historie PHP a souvisejících projektů
B. Přechod z PHP 3 na PHP 4
C. Přechod z PHP/FI 2 na PHP 3
D. Ladění (debugging) PHP
E. Extending PHP
F. Seznam aliasů funkcí
G. Seznam vyhrazených slov
H. List of Resource Types
I. List of Parser Tokens
J. O tomto manuálu
K. missing stuff

Příloha A. Historie PHP a souvisejících projektů

PHP urazilo v posledních několika málo letech dlouhou cestu. Růst v jeden z nejprominentnějších jazyků ovládajích Web nebyl snadný. Ti z vás, kdo máte zájem dozvědět se ve zkratce, jak PHP vyrostlo do dnešní podoby, čtěte dále.

Historie PHP

PHP/FI

PHP je nástupcem staršího produktu, nazvaného PHP/FI. PHP/FI vytvořil Rasmus Lerdorf v roce 1995, na počátku jako jednoduchou sadu skriptů v jazyce Perl pro zpracování záznamů o přístupech k jeho webu. Tuto sadu nazval 'Personal Home Page Tools'. Protože byla třeba větší funkčnost, napsal Rasmus mnohem rozsáhlejší implementaci v C, která byla schopna komunikovat s databázemi aumožňovala uživatelům vyvíjet jednoduché dynamické aplikace pro Web. Rasmus se rozhodl uvolnit zdrojový kód PHP/FI pro všechny, takže kdokoli ho může používat, stejně jako opravovat chyby a vylepšovat kód.

PHP/FI, což znamená Personal Home Page / Forms Interpreter, obsahovalo něco ze základní funkcionality PHP, jak ho známe dnes. Mělo proměnné perlovského typu, automatickou interpretaci formulářových proměnných a syntaxi vloženou do HTML. Syntaxe samotná byla podobná jazyku Perl, přestože mnohem omezenější, jednodušší a v něčem nekonzistentní.

V roce 1997 se PHP/FI 2.0, druhá implementace psaná v C, stala kultovní záležitostí pro (odhadem) tisíce uživatelů po celém světě, a s přibližně 50.000 doménami oznamujícími nainstalované PHP/FI, což čítalo zhruba 1 % všech domén na Internetu. I když do projektu začalo svými kusy kódu přispívat více lidí, stále to byl velký projekt jednoho muže.

PHP/FI 2.0 bylo oficiálně uvolněno až v listopadu 1997, poté co strávilo většinu svého života v betaverzích. Krátce nato bylo následováno první alfaverzí PHP 3.0.

PHP 3

PHP 3.0 byla první verze, která se velmi blížila takovému PHP, jak ho známe dnes. Vytvořili ho Andi Gutmans a Zeev Suraski v roce 1997 jako kompletně přepsaný celek, poté co shledali PHP/FI 2.0 výrazně "poddimenzované" pro vývoj svých aplikací pro e-komerci. Ve snaze spolupracovat a zahájit budování nad existující uživatelskou základnou PHP/FI, rozhodli se Andi, Rasmus a Zeev pracovat společně a prohlásit PHP 3.0 za oficiálního nástupce PHP/FI 2.0, a vývoj PHP/FI 2.0 byl v podstatě zastaven.

Jednou z nejsilnějších zbraní PHP 3.0 byly jeho obrovské možnosti rozšíření. K poskytnutí pevné infrastruktury pro mnoho různých databází, protokolů a API koncovým uživatelům, přilákaly možnosti rozšíření PHP 3.0 také tucty vývojářů, kteří se připojili a vytvořili nové rozšiřující moduly. Toto byl nesporně klíč k obrovskému úspěchu PHP 3.0. Jiným klíčovým prvkem v PHP 3.0 byla podpora objektově orientované syntaxe a mnohem silnější a konzistentnější syntaxe jazyka.

Nový jazyk byl uvolněn pod novým názvem, který odstranil implikaci omezeného osobního použití, kterou neslo označení PHP/FI 2.0. Byl nazván pouze 'PHP', což je rekurzívní akronym - PHP: Hypertext Preprocessor.

Na konci roku 1998 vyrostlo PHP do rozsahu instalací v řádu (odhadem) desítek tisíc uživatelů a stovek tisíc Webů. V době svého vrcholu bylo PHP 3.0 instalováno na přibližně 10 % všech WWW serverů na Internetu.

PHP 3.0 bylo oficiálně uvolněno v červnu 1998, poté co strávilo cca 9 měsíců ve veřejném testování.

PHP 4

V zimě 1998, krátce po oficiálním uvolnění PHP 3.0, začali Andi Gutmans a Zeev Suraski pracovat na přespání jádra PHP. Cílem návrhu bylo zvýšit výkon pro složité aplikace a zlepšit modularitu kódové báze PHP. Takové aplikace byly schopny pracovat s PHP 3.0 (díky novým možnostem a podpoře široké škály databází a API od jiných tvůrců), ale PHP 3.0 nebylo navrženo pro efektivní práci tak náročných aplikací.

Nový engine, nazvaný 'Zend Engine' (sestaven z jejich křestních jmen, Zeev a Andi), úspěšně splnil cíle návrhu a byl uveden v polovině roku 1999. PHP 4.0, založené na tomto enginu a doplněné širokou škálou nových prvků, bylo oficiálně uvolněno v květnu 2000, necelé dva roky po svém předchůdci, PHP 3.0. K podstatně zvýšenému výkonu této verze, přidává PHP 4.0 další klíčové prvky, jako je podpora pro mnoho WWW serverů, HTTP sessions, buffering výstupu, bezpečnější způsoby zpracování vstupů uživatele a mnoho nových jazykových konstruktů.

PHP 4 je momentálně poslední uvolněnou verzí PHP. Již byla započata práce na modifikaci a vylepšení jádra Zend Engine k integraci prvků, které byly navrženy pro PHP 5.0.

Dnes používají PHP (odhadem) stovky tisíc vývojářů a nainstalované PHP hlásí několik milionů serverů - tj. přes 20 % domén na Internetu.

Vývojový tým PHP zahrnuje tucty vývojářů, stejně tak jako tucty dalších lidí, kteří pracují na projektech spojených s PHP, jako je PEAR a dokumentační projekt.

Historie projektů souvisejících s PHP

PEAR

PEAR, PHP Extension and Application Repository (česky repozitář rozšíření a aplokací PHP) - původně PHP Extension and Add-on Repository (repozitář rozšíření a doplňků) - je PHP verze "foundation classes", a může v budoucnu vyrůst v jeden z klíčových způsobů distribuce jak PHP rozšíření, tak rozšíření PHP psaných v C, mezi vývojáře.

PEAR se zrodil v diskusi na mítinku PHP Developers' Meeting (PDM) v lednu 2000 v Tel Avivu. Byl vytvořen Stigem S. Bakkenem a delegován na jeho prvorozenou dceru Malin Bakken.

Od začátku roku 2000 PEAR vyrostl ve velký, významný projekt s velkým počtem vývojářů pracujících na společné, široce použitelné funkcionalitě ve prospěch celé PHP komunity. PEAR dnes zahrnuje širokou paletu infrastrukturních "foundation classes" pro přístup k databázím, cachování obsahu e-komerci a mnoho dalšího.

PHP Quality Assurance Initiative

PHP Quality Assurance Initiative (iniciativa zajištění kvality PHP) byla ustavena v létě 2000 v rakci na kritiku, že uvolněné verze PHP nebyly dostatečně testovány pro produkční prostředí. Tým nyní sestává z pevné skupiny vývojářů, kteří dobře rozumějí kódové bázi PHP. Tito vývojáři tráví mnoho času lokalizací a odstraňováním chyb v PHP. Navíc je zde mnoho členů týmu, kteří to pak testují a poskytují zpětnou vazbu na tyto opravy na široké škále platforem.

PHP-GTK

PHP-GTK je PHP řešení pro psaní GUI aplikací pro stranu klienta. Andrei Zmievski připomíná plánování a proces tvorby PHP-GTK:

Programování GUI vždy patřilo mezi mé zájmy a shledal jsem Gtk+ velmi příjemným toolkitem, kromě toho, že programovat s jeho použitím v C je někdy nudné. Po zkušenostech s PyGtk a GTK-Perl implemetacemi jsem se rozhodl podívat se, zda by se dalo v PHP vytvořit, alespoň trochu, rozhraní ke Gtk+. Počínaje srpnem 2000 jsem měl o něco více volného času, takže jsem začal experimentovat. Mým hlavním vodítkem byla implementace PyGtk, což bylo skutečně funkčně kompletní a příjemné objektově orientované rozhraní. James Henstridge, autor PyGtk, mi poskytl velmi užitečné rady během počatečního stádia vývoje.

Ruční psaní rozhraní ke všem funkcím Gtk+ bylo zcela mimo hru, takže jsem se zabýval ideou generátoru kódu, podobného jako v případě PyGtk. Generátor kódu je program v PHP, který čte sadu .defs souborů obsahujících informace o třídách, konstantách a metodách Gtk+ a generuje kód v C, který pro ně poskytuje rozhraní. Co nelze vygenerovat automaticky, může být napsáno ručně v souboru .overrides.

Práce na generátoru kódu a na infrastruktuře trvala nějakou dobu, protože jsem na podzim 2000 mohl práci na PHP-GTK věnovat jen málo času. Když jsem to pak ukázal Franku Kromannovi, byl zaujat a začal mi pomáhat s prací na generátoru kódu a implementaci pro Win32. Když jsme napsali první program "Ahoj světe!" a spustili ho, bylo to extrémně vzrušující. Trvalo to několik měsíců, než se projekt dostal do prezentovatelného stavu a úvodní verze byla uvolněna 1 .března 2001. Příběh okamžitě zasáhl SlashDot.

S ohledem na to, jak může být projekt PHP-GTK rozsáhlý, založil jsem pro něj samostatné diskusní skupiny a CVS repozitáře, stejně jako (s pomocí Colina Viebrocka) webovskou stránku gtk.php.net. Také by bylo třeba udělat dokumentaci a James Moore přispěchal pomoci s ní.

Uvolněná verze PHP-GTK si již získala popularitu. Máme vlastní dokumentační tým, manuál se stále zlepšuje, lidé začínají psát rozšíření pro PHP-GTK, a víc a víc vzrušujících aplikací.

Knihy o PHP

Jak PHP rostlo, začalo být považováno za celosvětově populární vývojovou platformu. Jedním z nejzajímavějších způsobů pozorování tohoto trendu je sledování knih o PHP vydávaných během posledních let.

Pokud si dobře pamatujeme, první kniha zaměřená na PHP 'PHP - Dynamische Webauftritte professionell realisieren' - německá kniha publikovaná v roce 1999, autory byli Egon Schmid, Christian Cartus and Richard Blume. První kniha v angličtině byla vydána krátce nato: 'Core PHP Programming' od Leona Atkinsona. Obě tyto knihy se zabývaly PHP 3.0.

Tyto dvě knihy byly první svého druhu - a byly následovány velkým množstvím knih různých autorů a vydavatelů. Existuje přes 40 knih v angličtině, 50 knih v němčině a přes 20 knih ve francouzštině. Navíc můžete najít knihy o PHP v mnoha dalších jazycích včetně španělštiny, korejštiny, japonštiny a hebrejštiny.

Samozřejmě, tento velký počet knih, psaných různými autory, vydávaných mnoha vydavateli a jejich dostupnost v tolika jazycích - je potvrzením celosvětového úspěchu PHP.

Ostatní publikace o PHP

Podle našich nejlepších informací byl první článek o PHP v tištěném časopisu publikován ve French Informatiques Magazine na konci roku 1998 a zabýval se PHP 3.0. Stejně jako v případě knih byl první v dlouhé řadě článků publikovaných v různých uznávaných časopisech.

Články o PHP se objevily v časopisech Dr. Dobbs, Linux Enterprise, Linux Magazine a mnoha dalších. Články o přechod z aplikací založených na ASP na platformu PHP pod Windows se objevily dokonce na ryze Microsoftím MSDN!

Příloha B. Přechod z PHP 3 na PHP 4

Co se změnilo v PHP 4

PHP 4 a integrovaný Zend engine se vyznačuje podstatně vyšším výkonem a schopnostmi, přesto však byla věnována zvláštní péče tomu, dopady na stávající kód byly co nejmenší. Takže úpravy vašeho kódu z PHP 3 na PHP 4 by měly být podstatně snadnější než při přechodu z PHP/FI 2.0 na PHP 3. Mnoho existujícího kódu pro PHP 3 by mělo být připraveno běžet bez jakýchkoli změn, měli byste však vědět o několika podstatných odlišnostech a věnovat dobrou péči otestování kódu před změnou verze produkčního prostředí. Následující text by vám měl poradit, na co se zaměřit.

Současný běh PHP 3 a PHP 4

Nejnovější operační systémy poskytují možnost versioningu a scopingu. Tyto prostředky umožňují nechat běžet PHP 3 a PHP 4 současně na jediném serveru Apache.

Funkce je ověřena na těchto platformách:

Linux + nejnovější binutils (testována verze binutils 2.9.1.0.25)
Solaris 2.5 a novější
FreeBSD (testovány verze 3.2 a 4.0)

K aktivaci této možnosti je třeba nakonfigurovat PHP 3 a PHP 4 k použití APXS (--with-apxs) a nezbytných rozšíření vazeb (--enable-versioning). Jinak postupujte zcela standardním způsobem (pro konfiguraci, kompilaci a instalaci). Například:

$ ./configure \
  --with-apxs=/apache/bin/apxs \
  --enable-versioning \
  --with-mysql \
  --enable-track-vars

Převod konfiguračních souborů

Název globálního konfiguračního souboru, php3.ini, se změnil na php.ini.

V konfiguračním souboru serveru Apache je poněkud více změn. Změnily se především MIME datové typy rozpoznávané modulem PHP.

application/x-httpd-php3        -->    application/x-httpd-php
application/x-httpd-php3-source -->    application/x-httpd-php-source

Můžete upravit vaše konfigurační soubory tak, aby pracovaly s oběma verzemi PHP (v závislosti na tom, která je v příslušném okamžiku zkompilována pro server) použitím následující syntaxe:

AddType  application/x-httpd-php3        .php3
AddType  application/x-httpd-php3-source .php3s

AddType  application/x-httpd-php         .php
AddType  application/x-httpd-php-source  .phps

Změnily se také názvy direktiv pro server Apache.

Od verze PHP 4.0 existují pouze čtyři direktivy pro Apache, které mají spojitost s PHP:

php_value [PHP directive name] [value]
php_flag [PHP directive name] [On|Off]
php_admin_value [PHP directive name] [value]
php_admin_flag [PHP directive name] [On|Off]

Jsou dva rozdíly mezi hodnotami "admin" a ostatními:

Hodnoty (nebo příznaky) "admin" se mohou objevit pouze v konfiguračních souborech pro celý server (např. httpd.conf).
Standardní hodnoty (nebo příznaky) nemohou ovládat jisté PHP direktivy, například bezpečný režim (pokud byste mohli změnit nastavení bezpečného režimu v souborech .htaccess, bezpečný režim ztrácí smysl). Naopak, "admin" hodnoty mohou zasahovat do jakýchkoli PHP direktiv.

Aby byl přechod na novou verzi snazší, balík PHP 4 obsahuje skripty, které automaticky převedou váš konfigurační soubor pro Apache a soubory .htaccess tak, aby pracovaly jak s PHP 3, tak s PHP 4. Tyto skripty NEPŘEVÁDĚJÍ řádky s popisy MIME typů! Musíte je upravit ručně.

K převedení konfiguračních souborů pro Apache, spusťte skript apconf-conv.sh (umístěný v adresáři scripts/apache/). Například:

~/php4/scripts/apache:#  ./apconf-conv.sh /usr/local/apache/conf/httpd.conf

Váš originální konfigurační soubor bude uložen jako httpd.conf.orig.

K převedení souborů .htaccess, spusťte skript aphtaccess-conv.sh (dostupný rovněž v adresáři scripts/apache/):

~/php4/scripts/apache:#  find / -name .htaccess -exec ./aphtaccess-conv.sh {} \;

I v tomto případě budou originální soubory .htaccess uloženy s koncovkou .orig.

Konverzní skripty vyžadují nainstalovaný nástroj awk.

Chování parseru

Parsing a provádění kódu jsou nyní dva naprosto oddělené kroky, nic z kódu v souboru se neprovádí dříve, než je úspěšně provedena úplná syntaktická analýza celého souboru a všeho, co je třeba.

Jeden z nových požadavků, které vyvstaly tímto rozdělením, je, že všechny soubory připojené prostřednictvím "require" a "include" nyní musí být syntakticky úplné. Již nelze rozložit různé části řídicích konstrukcí přes hranice souborů. Tj. nelze začít cyklus for nebo while, větvení if nebo switch v jednom souboru a ukočit je (resp. pokračovat pomocí else, endif, case nebo break) v souboru jiném.

Zůstává zcela legální vložit další kód do cyklů nebo jiných řídicích struktur, pouze řídicí klíčová slova a odpovídající složené závorky {...} musí být ve stejné kompilační jednotce (souboru nebo řetězci zpracovaném pomocí eval()).

Toto neškodí tolik jako výše uvedené rozkládání kódu, přesto to může být považováno za velmi špatný styl.

Jinou věcí, která již není možná, je vzácně vídané vracení hodnot ze souborů připojených pomocí "require". Vracení hodnot ze souborů připojených "include" je možné i nadále.

Hlášení chyb

Změny konfigurace

Hlášení chyb v PHP 3 bylo založeno na úrovních, představovaných jednoduchou číselnou hodnotou. Hodnoty se sčítaly pro různé úrovně chyb. Obvyklé hodnoty byly 15 pro hlášení všech chyb a varování, 7 pro hlášení všeho kromě informativních zpráv, ohlašujících špatný styl a podobné věci.

PHP 4 má větší množinu úrovní chyb a varování a přichází s konfiguračním parserem, který nyní umožňuje k nastavení potřebného chování používat symbolické konstanty.

Úroveň hlášení chyb by měla být nyní nastavována explicitním odebíráním těch úrovní, u kterých které nechceme, aby byly hlášeny (pomocí logické operace XOR se symbolickou konstantou). E_ALL. Zní to komplikovaně? No, tak řekněme, že chcete hlásit všechny chyby s výjimkou jednoduchých "stylových" varování, která jsou zařazena do kategorie popsané symbolickou konstantou E_NOTICE. Potom do souboru php.ini vložíte: error_reporting = E_ALL & ~ ( E_NOTICE ). Pokud chcete potlačit také všechna varování, přidáte odpovídající konstantu do závorek s použitím binárního operátoru '|': error_reporting= E_ALL & ~ ( E_NOTICE | E_WARNING ).

Varování

Používání starých hodnot 7 a 15 pro nastavení hlášení chyb je velmi špatný nápad, protože to potlačuje některé nově přidané třídy chyb včetně syntaktických. To může vést k velmi záhadnému chování, kdy skripty nepracují, aniž by vydaly jakoukoli zprávu o chybě.

Toto v minulosti vedlo k množství nereprodukovatelných bug reportů (hlášení o chybách v PHP), když lidé hlásili problémy s enginem, které nebyli schopni vystopovat. Pravou příčinou byla obvykle chybějící uzavírací závorka '}' v souboru připojeném pomocí "require", a parser je nemohl ohlásit kvůli špatně nakonfigurovanému hlášení chyb.

Takže kontrola nastavení hlášení chyb by měla být první věcí, pokud vaše skripty tiše havarují. Zend engine může být nyní považován za dost vyspělý na to, aby způsoboval takové podivné chování.

Přídavné varovné zprávy

Mnoho existujících kódů v PHP 3 používá jazykové konstrukty, které by měly být považovány za velmi špatný styl psaní, neboť přestože nyní dělají zamýšlené věci, snadno mohou být narušeny změnami jinde. PHP 4 bude vydávat spousty informativních zpráv v takových situacích, kdy se v PHP 3 nic nedělo. Snadnou nápravou je vypnutí zpráv E_NOTICE, ale obvykle je lepší raději opravit kód.

Nejčastějším případem, který bude produkovat takové zprávy, je použití řetězců bez uvozovek jako prvků pole. Jak PHP 3, tak PHP 4 je budou interpretovat jako řetězce, pokud pod tímto jménem není známo žádné klíčové slovo ani konstanta. Pokud by však nějaká taková konstanta (někde jinde v kódu) definována byla, skript může havarovat. Může to přerůst i v bezpečnostní riziko, pokud nějaký útočník předefinuje řetězcové konstanty způsobem, který mu dá přístupová práva, jež by mít neměl. Takže PHP 4 vás bude nyní varovat, pokud použijete řetězecovou konstantu neuzavřenou do uvozovek, jako například $HTTP_SERVER_VARS[REQUEST_METHOD]. Změníte-li to na $HTTP_SERVER_VARS['REQUEST_METHOD'], parser se uklidní a výrazně se zlepší styl a bezpečnost vašeho kódu.

Další věcí v PHP 4 je hlášení použití neinicializovaných proměnných a prvků polí.

Inicializátory

Statické proměnné a inicializátory položek tříd přijímají pouze skalární hodnoty, zatímco v PHP 3 přijímaly i jakékoli platné výrazy. Toto je, opět, kvůli rozdělení mezi parsing a provádění kódu - když parser zpracovává inicializátor, ještě není proveden žádný kód.

K inicializaci položek ve třídách byste měli namísto toho používat konstruktory. Pro statické proměnné přesto vzácně dává smysl i něco jiného než obyčejná hodnota.

`empty("0")`

Asi nejkontroverznější změnou v chování je změna ve funkci empty(). Řetězec obsahující pouze znak '0' (nula) je nyní považován za prázdný, což v PHP 3 nebylo.

Toto nové chování má smysl u aplikací pro web tam, kde všechna vstupní pole vrací řetězce, i když je požadován číselný vstup, a se schopností PHP provádět automatickou typovou konverzi. Na druhou stranu může v některých případech vést k chybnému chování, jehož příčiny se špatně zjištují, pokud nevíte, co máte hledat.

Chybějící funkce

Současně s tím, že se v PHP 4 objevuje mnoho nových prostředků, funkcí a rozšíření, můžete najít i funkce, které oproti verzi 3 chybí. Malý počet jádrových funkcí zmizel, protože nefungují s novým schématem oddělení parsingu a provádění kódu v Zend enginu. Jiné funkce i celá kompletní rozšíření se staly zastaralými tím, že novější funkce a rozšíření poslouží ve stejné roli lépe nebo obecněji. Některé funkce jednoduše ještě nebyly portovány a konečně jsou také funkce a rozšíření chybějící kvůli licenčním konfliktům.

Funkce chybějící kvůli konceptuálním změnám

Tím, že PHP 4 odděluje syntaktickou analýzu od interpretace, již není možné měnit chování parseru (nyní vloženého do Zend enginu) během provádění skriptu, který byl již syntakticky zpracován. Takže funkce short_tags() již neexistuje. Měnit chování parseru stále můžete, a to nastavením hodnot v souboru php.ini.

Jiným prostředkem PHP 3, který není součástí PHP 4, je zabudované rozhraní pro ladění. Existují externí doplňky pro Zend engine, které poskytují podobné funkce.

Zavržené funkce a rozšíření

Databázová rozšíření Adabas a Solid již nejsou k dispozici. Namísto toho se používá rozšíření unifikované rozhraní ODBC.

Změněný status funkce unset()

unset(), přestože je stále k dispozici, je implementována jako jazykový konstrukt namísto funkce.

To nemá žádné důsledky v chování unset(), ale test "unset" pomocí function_exists() vrátí FALSE, stejně jako v případě jiných jazykových konstruktů, které vypadají jako funkce, např. echo().

Jinou, praktičtější změnou je to, že již nelze volat unset() nepřímo, tzn. $func="unset"; $func($somevar) už nebude fungovat.

Rozšíření PHP 3

Rozšíření psaná pro PHP 3 nebudou s PHP 4 pracovat, ani na binární, ani na zdrojové úrovni. Není těžké portovat tato rozšíření na PHP 4, pokud máte přístup k originálnímu zdrojovému kódu. Detailní popis procesu portace není součástí tohoto textu.

Substituce za proměnné v řetězcích

PHP 4 přidává nový mechanismus k substituci za proměnné v řetězcích. Nyní můžete konečně uvnitř řetězců přistupovat k položkám v objektech a k prvkům vícerozměrných polí.

To se udělá pomocí uzavření proměnných do složených závorek se znakem dolaru ihned za otvírací závorkou: {$...}

K vložení hodnoty položky objektu do řetězce jednoduše napíšete "text {$obj->member} text", zatímco v PHP 3 jste museli napsat něco jako "text ".$obj->member." text".

Toto by mělo vést k čitelnějšímu kódu, ale může to způsobovat problémy s existujícími skripty pro PHP 3. Můžete ale provést test na kombinaci znaků {$ ve vašem kódu a jejich nahrazení \{$ pomocí vašeho oblíbeného nástroje pro hledání a náhradu.

Cookies

V PHP 3 se zavedl špatný zvyk nastavovat cookies opačným pořadím volání setcookie() v kódu. PHP 4 toto napravuje a vytváří hlavičkové řádky pro cookies v přesně stejném pořadí, jak jdou za sebou v kódu.

Opět se mohou vyskytnout problémy s existujícím kódem, ale staré chování bylo tak těžko pochopitelné, že si zasloužilo změnu, aby se zabránilo dalším problémům v budoucnosti.

Obsluha globálních proměnných

Zatímco v PHP 3 a prvních verzích PHP 4 se při obsluze globálních proměnných dbalo především na jednoduchost, nyní se zaměření změnilo směrem k vyšší bezpečnosti. Takže jestliže následující případ dobře fungoval v PHP 3, v PHP 4 je třeba provést unset($GLOBALS["id"]);. Toto je jen jeden aspekt obsluhy globálních proměnných. Měli byste vždy používat $GLOBALS, v novějších verzích PHP 4 budete nuceni tak učinit ve většině případů. Více o této problematice najdete v části global (globální) reference.

Příklad B-1. Změny u globálních proměnných

<?php
$id = 1;
function test()
{
    global $id;
    unset($id);
}
test();
echo($id); // This will print out 1 in PHP 4

Příloha C. Přechod z PHP/FI 2 na PHP 3

O nekompatibilitách v 3.0

PHP 3.0 je od základu přepsáno. Má náležitý parser, který je mnohem robustnější a konzistentnější než ten ve verzi 2.0. Verze 3.0 je také signifikantně rychlejší a používá méně paměti. Logicky, některá z těchto vylepšení nebyla možná bez změnách v kompatibilitě, jak v syntaxi, tak ve funkcionalitě.

Navíc se vývojáři PHP snažili vyčistit jak syntaxi, tak sémantiku PHP, což také přineslo nějaké nekompatibility. Ze širšího pohledu, věříme že tyto změny jsou pro dobro věci.

Tato kapitola se pokusí provést vás nekompatibilitami, na které můžete narazit při přechodu z PHP/FI 2.0 na PHP 3.0 a pomoci vám je vyřešit. Nové prvky zde nebudou zmiňovány, pokud to nebude nutné.

Konverzní program, který automaticky převede vaše staré skripty v PHP/FI 2.0, existuje. Najdete ho adresáři convertor v distribuci PHP 3.0. Tento program však zachycuje pouze změny syntaxe, takže přesto pozorně čtěte tuto kapitolu.

Otvírací/uzavírací značky (start/end tags)

Pravděpodobně první věcí, kterou zaznamenáte, je, že se změnily otevírací a uzavírací značky (označují začátek a konec kódu PHP). Staré značky <? > byly nahrazeny třemi možnými formami:

Příklad C-1. Přechod: staré otvírací/uzavírací značky

<? echo "This is PHP/FI 2.0 code.\n"; >
Jako verze 2.0, PHP 3.0 podporuje také tuto variantu:

Příklad C-2. Přechod: první otvírací/uzavírací značky

<? echo "This is PHP 3.0 code!\n"; ?>
Všimněte si, že uzavírací značka nyní sestává z otazníku a znaku "větší než" namísto pouhého znaku "větší než". Bohužel, pokud na svém serveru plánujete používat XML, bude tato varianta dělat problémy, protože se PHP může pokoušet interpretovat XML značku jako PHP kód. Z tohoto důvodu byla zavedena nová varianta:

Příklad C-3. Přechod: druhé otvírací/uzavírací značky

<?php echo "This is PHP 3.0 code!\n"; ?>
Někteří lidé mají problémy s editory, které zcela neporozumí zpracování instrukčních značek. Jedním z takových editorů je Microsoft FrontPage, a jako řešení tohoto problému byla přidána ještě další varianta:

Příklad C-4. Přechod: třetí otvírací/uzavírací značky

<script language="php"> echo "This is PHP 3.0 code!\n"; </script>

syntaxe if..endif

Alternativní způsob, jak zapsat konstrukci if/elseif/else, za použití if(); elseif(); else; endif;, nemůže být efektivně implementována bez podstatného nárůstu složitosti 3.0 parseru. Kvůli tomu se změnila syntaxe:

Příklad C-5. Přechod: stará syntaxe if..endif

if ($foo); echo "yep\n"; elseif ($bar); echo "almost\n"; else; echo "nope\n"; endif;

Příklad C-6. Přechod: nová syntaxe if..endif

if ($foo): echo "yep\n"; elseif ($bar): echo "almost\n"; else: echo "nope\n"; endif;
Všimněte si, že středníky byly nahrazeny dvojtečkami ve všech konstruktech kromě závěrečného (endif).

syntaxe while

Stejně jako if..endif, syntaxe while..endwhile byla změněna:

Příklad C-7. Přechod: stará syntaxe while..endwhile

while ($more_to_come); ... endwhile;

Příklad C-8. Přechod: nová syntaxe while..endwhile

while ($more_to_come): ... endwhile;

Varování

Pokud v PHP 3.0 použijete starou syntaxi while..endwhile, získáte nekonečnou smyčku.

Typy výrazů

PHP/FI 2.0 používalo levou stranu výrazů k určení, jakého typu má výsledek být. PHP 3.0 bere pro určení typu v úvahu obě strany výrazu, a to může způsobit nepředvídatelné chování 2.0 skriptů v PHP 3.0.

Uvažujme tento příklad:

$a[0]=5;
$a[1]=7;

$key = key($a);
while ("" != $key) {
    echo "$keyn";
    next($a);
}

V PHP/FI 2.0 by to zobrazilo obě hodnoty v $a. V PHP 3.0 se však nezobrazí nic. Důvod je ten, že PHP 2.0 kvůli tomu, že na levé straně je řetezec, provede porovnání řetězců, a "" se nerovná "0", tedy se bude procházet cyklem. V PHP 3.0 se řetězec porovná s celým číslem (integer), provede se porovnání celých čísel (řetězec je převeden na celé číslo). Výsledkem je porovnání atoi(""), což je 0, a variablelist, což je také 0. A protože 0==0, cyklem se vůbec procházet nebude.

Oprava pro tento příklad je snadná. Nahraďte původní konstrukci tímto:

while ((string)$key != "") {

Chybové zprávy se změnily

Chybové zprávy PHP 3.0 jsou obvykle přesnější, než byly ve 2.0. Neuvidíte však část kódu, kde nastala chyba. Vypíše se pouze název souboru a číslo řádku, kde nastala chyba.

Zkrácené vyhodnocení logických výrazů

V PHP 3.0 se používá zkrácené vyhodnocení logických výrazů. To znamená, že pro výraz jako (1 || test_me()) již nebude funkce test_me() volána, protože za 1 již nic nemůže ovlivnit hodnotu výrazu.

Toto je malá změna kompatibility,ale může způsobit neočekávané vedlejší efekty.

Návratové hodnoty `TRUE`/`FALSE`

Většina vnitřních funkcí byla přepsána tak, aby vracela TRUE v případě úspěchu a FALSE při selhání, narozdíl od původních hodnot 0 a -1 v PHP/FI 2.0. Nové chování umožňuje logičtější programování, jako $fp = fopen("/your/file") nebo fail("darn!");. Protože v PHP/FI 2.0 nebyla jasná pravidla, v kterých případech se vyskakovalo z funkce při selhání, většina skriptů bude pravděpodobně muset být zkontrolována ručně po použití konvertoru z 2.0 na 3.0.

Příklad C-9. Přechod z 2.0: návratové hodnoty, starý kód

$fp = fopen($file, "r"); if ($fp == -1); echo("Could not open $file for reading<br>\n"); endif;

Příklad C-10. Přechod z 2.0: návratové hodnoty, nový kód

$fp = @fopen($file, "r") or print("Could not open $file for reading<br>\n");

Jiné nekompatibility

Modul PHP 3.0 pro Apache již nepodporuje verze Apache starší než 1.2. Je třeba Apache 1.2 nebo pozdější.
Funkce echo() již nepodporuje formátovaný řetězec. Použijte namísto toho printf().
V PHP/FI 2.0 způsobovaly vedlejší efekty implementace to, že $foo[0] mělo stejný účinek jako $foo. Toto již v PHP 3.0 neplatí
Čtení z polí pomocí $array[] již není podporováno.

To znamená, že nemůžete traverzovat pole v cyklu, který provádí $data = $array[]. Použijte funkce current() a next().

Současně $array1[] = $array2 nepřipojuje hodnoty pole $array2 k poli $array1, nýbrž připojuje pole $array2 jako poslední položku pole $array1. Viz též: podpora vícerozměrných polí.
"+" již není přetěžován jako spojovací operátor pro řetězce, namísto toho konvertuje řetězce na čísla a provede jejich (numerický) součet. Použijte tedy operátor "." instead.

Příklad C-11. Přechod z 2.0: spojení řetězců

echo "1" + "1";

V PHP 2.0 by se vypsalo 11, v PHP 3.0 se vypíše 2. Když místo toho použijete:

echo "1"."1";

$a = 1; $b = 1; echo $a + $b;

vypíše se 2 v PHP 2.0 i 3.0.

$a = 1; $b = 1; echo $a.$b;
Toto v PHP 3.0 vypíše 11.

Příloha D. Ladění (debugging) PHP

O debuggeru

PHP 3 obsahuje pro podporu pro síťově založený debugger.

PHP 4 nemá vnitřní mechanismy pro ladění. Nicméně můžete používat některý z externích debuggerů. Zend IDE obsahuje debugger, a ladicí rozšíření (jako DBG) najdete také na http://dd.cron.ru/dbg/ nebo na Advanced PHP Debugger (APD).

Použití debuggeru

Vnitřní debugger v PHP 3 je užitečný pro hledání záludných chyb. Debugger pracuje prostřednictvím připojení na TCP port při každém startu PHP 3. Všechny chybové zprávy z příslušné relace jsou posílány do tohoto TCP kanálu. Tyto informace jsou určeny pro "debugging server", který může běžet uvnitř IDE nebo programovatelného editoru (jako je Emacs).

Jak nastavit debugger:

Nastavte TCP port pro debugger v konfiguračním souboru (debugger.port) a aktivujte ho (debugger.enabled).
Nastavte TCP pro poslech na nějakém portu (například socket -l -s 1400 v UNIXu).
Ve vašem kódu spusťte "debugger_on(host)", kde host je IP adresa nebo doménový název počítače, kde běží příslušný TCP server.

Nyní budou všechna varování, informativní zprávy apod. mířit na síťový socket, a to i tehdy, pokud je vypnete pomocí nastavení error_reporting().

Protokol debuggeru

Protokol PHP 3 debuggeru je řádkově orientovaný. Každý řádek je určitého typu a několik řádků tvoří zprávu. Každá zpráva začíná řádkem typu start a končí řádkem typu end. PHP 3 může současně posílat řádky pro různé zprávy.

Řádek má tento formát:

date time
host(pid)
type:
message-data

date

Datum ve formátu ISO 8601 (yyyy-mm-dd)

time

Čas včetně mikrosekund: hh:mm:uuuuuu

host

DNS (doménový) název nebo IP adresa počítače, kde byla vygenerována chyba ve skriptu.

pid

PID (process id) na počítači host procesu, který vygeneroval chybu v PHP 3 skriptu.

type

Typ řádku. Říká přijímajícímu programu, jak má s následujícími daty naložit:

Tabulka D-1. Typy řádků debuggeru

Název	Význam
`start`	Říká přijímajícímu programu, že tady začíná zpráva debuggeru. Obsahem datové části (`data`)bude typ chybové zprávy z níže uvedeného seznamu.
`message`	Chybová zpráva PHP 3.
`location`	Název souboru a číslo řádku, kde nastala chyba. První řádek `location` bude vždy obsahovat nejvyšší úroveň umístění. `data` bude obsahovat `file:line`. Řádek `location` bude následovat za každým řádkem `message` a každým řádkem `function`.
`frames`	Počet rámců v následujícím výpisu zásobníku. Pokud jsou zde čtyři rámce, očekávejte informace o čtyřech úrovních volaných funkcí. Pokud se žádný řádek "frames" nevyskytuje, předpokládá se hloubka 0 (chyba nastala na nejvyšší úrovni).
`function`	Název funkce, kde nastala chyba. Bude se opakovat pro každou úroveň zásobníku volání funkcí.
`end`	Říká přijímajícímu programu, že tady končí zpráva debuggeru.

data

Data v řádku.

Tabulka D-2. Typy chyb rozlišované debuggerem

Debugger	PHP 3 Internal
warning	E_WARNING
error	E_ERROR
parse	E_PARSE
notice	E_NOTICE
core-error	E_CORE_ERROR
core-warning	E_CORE_WARNING
unknown	(všechny ostatní)

Příklad D-1. Příklad - zpráva debuggeru

1998-04-05 23:27:400966 lucifer.guardian.no(20481) start: notice
1998-04-05 23:27:400966 lucifer.guardian.no(20481) message: Uninitialized variable
1998-04-05 23:27:400966 lucifer.guardian.no(20481) location: (NULL):7
1998-04-05 23:27:400966 lucifer.guardian.no(20481) frames: 1
1998-04-05 23:27:400966 lucifer.guardian.no(20481) function: display
1998-04-05 23:27:400966 lucifer.guardian.no(20481) location: /home/ssb/public_html/test.php3:10
1998-04-05 23:27:400966 lucifer.guardian.no(20481) end: notice

Příloha E. Extending PHP

Adding functions to PHP

Function Prototype

All functions look like this:

void php3_foo(INTERNAL_FUNCTION_PARAMETERS) { }
Even if your function doesn't take any arguments, this is how it is called.

Function Arguments

Arguments are always of type pval. This type contains a union which has the actual type of the argument. So, if your function takes two arguments, you would do something like the following at the top of your function:

Příklad E-1. Fetching function arguments

pval *arg1, *arg2; if (ARG_COUNT(ht) != 2 || getParameters(ht,2,&arg1,&arg2)==FAILURE) { WRONG_PARAM_COUNT; }
NOTE: Arguments can be passed either by value or by reference. In both cases you will need to pass &(pval *) to getParameters. If you want to check if the n'th parameter was sent to you by reference or not, you can use the function, ParameterPassedByReference(ht,n). It will return either 1 or 0.

When you change any of the passed parameters, whether they are sent by reference or by value, you can either start over with the parameter by calling pval_destructor on it, or if it's an ARRAY you want to add to, you can use functions similar to the ones in internal_functions.h which manipulate return_value as an ARRAY.

Also if you change a parameter to IS_STRING make sure you first assign the new estrdup()'ed string and the string length, and only later change the type to IS_STRING. If you change the string of a parameter which already IS_STRING or IS_ARRAY you should run pval_destructor on it first.

Variable Function Arguments

A function can take a variable number of arguments. If your function can take either 2 or 3 arguments, use the following:

Příklad E-2. Variable function arguments

pval *arg1, *arg2, *arg3; int arg_count = ARG_COUNT(ht); if (arg_count < 2 || arg_count > 3 || getParameters(ht,arg_count,&arg1,&arg2,&arg3)==FAILURE) { WRONG_PARAM_COUNT; }

Using the Function Arguments

The type of each argument is stored in the pval type field. This type can be any of the following:

Tabulka E-1. PHP Internal Types

IS_STRING	String
IS_DOUBLE	Double-precision floating point
IS_LONG	Long integer
IS_ARRAY	Array
IS_EMPTY	None
IS_USER_FUNCTION	??
IS_INTERNAL_FUNCTION	?? (if some of these cannot be passed to a function - delete)
IS_CLASS	??
IS_OBJECT	??

If you get an argument of one type and would like to use it as another, or if you just want to force the argument to be of a certain type, you can use one of the following conversion functions:

convert_to_long(arg1); convert_to_double(arg1); convert_to_string(arg1); convert_to_boolean_long(arg1); /* If the string is "" or "0" it becomes 0, 1 otherwise */ convert_string_to_number(arg1); /* Converts string to either LONG or DOUBLE depending on string */

These function all do in-place conversion. They do not return anything.

The actual argument is stored in a union; the members are:

IS_STRING: arg1->value.str.val
IS_LONG: arg1->value.lval
IS_DOUBLE: arg1->value.dval

Memory Management in Functions

Any memory needed by a function should be allocated with either emalloc() or estrdup(). These are memory handling abstraction functions that look and smell like the normal malloc() and strdup() functions. Memory should be freed with efree().

There are two kinds of memory in this program: memory which is returned to the parser in a variable, and memory which you need for temporary storage in your internal function. When you assign a string to a variable which is returned to the parser you need to make sure you first allocate the memory with either emalloc() or estrdup(). This memory should NEVER be freed by you, unless you later in the same function overwrite your original assignment (this kind of programming practice is not good though).

For any temporary/permanent memory you need in your functions/library you should use the three emalloc(), estrdup(), and efree() functions. They behave EXACTLY like their counterpart functions. Anything you emalloc() or estrdup() you have to efree() at some point or another, unless it's supposed to stick around until the end of the program; otherwise, there will be a memory leak. The meaning of "the functions behave exactly like their counterparts" is: if you efree() something which was not emalloc()'ed nor estrdup()'ed you might get a segmentation fault. So please take care and free all of your wasted memory.

If you compile with "-DDEBUG", PHP will print out a list of all memory that was allocated using emalloc() and estrdup() but never freed with efree() when it is done running the specified script.

Setting Variables in the Symbol Table

A number of macros are available which make it easier to set a variable in the symbol table:

SET_VAR_STRING(name,value)
SET_VAR_DOUBLE(name,value)
SET_VAR_LONG(name,value)

Varování

Be careful with SET_VAR_STRING. The value part must be malloc'ed manually because the memory management code will try to free this pointer later. Do not pass statically allocated memory into a SET_VAR_STRING.

Symbol tables in PHP are implemented as hash tables. At any given time, &symbol_table is a pointer to the 'main' symbol table, and active_symbol_table points to the currently active symbol table (these may be identical like in startup, or different, if you're inside a function).

The following examples use 'active_symbol_table'. You should replace it with &symbol_table if you specifically want to work with the 'main' symbol table. Also, the same functions may be applied to arrays, as explained below.

Příklad E-3. Checking whether $foo exists in a symbol table

if (hash_exists(active_symbol_table,"foo",sizeof("foo"))) { exists... } else { doesn't exist }

Příklad E-4. Finding a variable's size in a symbol table

hash_find(active_symbol_table,"foo",sizeof("foo"),&pvalue); check(pvalue.type);
Arrays in PHP are implemented using the same hashtables as symbol tables. This means the two above functions can also be used to check variables inside arrays.

If you want to define a new array in a symbol table, you should do the following.

First, you may want to check whether it exists and abort appropriately, using hash_exists() or hash_find().

Next, initialize the array:

Příklad E-5. Initializing a new array

pval arr; if (array_init(&arr) == FAILURE) { failed... }; hash_update(active_symbol_table,"foo",sizeof("foo"),&arr,sizeof(pval),NULL);
This code declares a new array, named $foo, in the active symbol table. This array is empty.

Here's how to add new entries to it:

Příklad E-6. Adding entries to a new array

pval entry; entry.type = IS_LONG; entry.value.lval = 5; /* defines $foo["bar"] = 5 */ hash_update(arr.value.ht,"bar",sizeof("bar"),&entry,sizeof(pval),NULL); /* defines $foo[7] = 5 */ hash_index_update(arr.value.ht,7,&entry,sizeof(pval),NULL); /* defines the next free place in $foo[], * $foo[8], to be 5 (works like php2) */ hash_next_index_insert(arr.value.ht,&entry,sizeof(pval),NULL);
If you'd like to modify a value that you inserted to a hash, you must first retrieve it from the hash. To prevent that overhead, you can supply a pval ** to the hash add function, and it'll be updated with the pval * address of the inserted element inside the hash. If that value is NULL (like in all of the above examples) - that parameter is ignored.

hash_next_index_insert() uses more or less the same logic as "$foo[] = bar;" in PHP 2.0.

If you are building an array to return from a function, you can initialize the array just like above by doing:

if (array_init(return_value) == FAILURE) { failed...; }

...and then adding values with the helper functions:

add_next_index_long(return_value,long_value);
add_next_index_double(return_value,double_value);
add_next_index_string(return_value,estrdup(string_value));

Of course, if the adding isn't done right after the array initialization, you'd probably have to look for the array first:

pval *arr; if (hash_find(active_symbol_table,"foo",sizeof("foo"),(void **)&arr)==FAILURE) { can't find... } else { use arr->value.ht... }

Note that hash_find receives a pointer to a pval pointer, and not a pval pointer.

Just about any hash function returns SUCCESS or FAILURE (except for hash_exists(), which returns a boolean truth value).

Returning simple values

A number of macros are available to make returning values from a function easier.

The RETURN_* macros all set the return value and return from the function:

RETURN
RETURN_FALSE
RETURN_TRUE
RETURN_LONG(l)
RETURN_STRING(s,dup) If dup is TRUE, duplicates the string
RETURN_STRINGL(s,l,dup) Return string (s) specifying length (l).
RETURN_DOUBLE(d)

The RETVAL_* macros set the return value, but do not return.

RETVAL_FALSE
RETVAL_TRUE
RETVAL_LONG(l)
RETVAL_STRING(s,dup) If dup is TRUE, duplicates the string
RETVAL_STRINGL(s,l,dup) Return string (s) specifying length (l).
RETVAL_DOUBLE(d)

The string macros above will all estrdup() the passed 's' argument, so you can safely free the argument after calling the macro, or alternatively use statically allocated memory.

If your function returns boolean success/error responses, always use RETURN_TRUE and RETURN_FALSE respectively.

Returning complex values

Your function can also return a complex data type such as an object or an array.

Returning an object:

Call object_init(return_value).
Fill it up with values. The functions available for this purpose are listed below.
Possibly, register functions for this object. In order to obtain values from the object, the function would have to fetch "this" from the active_symbol_table. Its type should be IS_OBJECT, and it's basically a regular hash table (i.e., you can use regular hash functions on .value.ht). The actual registration of the function can be done using:
add_method( return_value, function_name, function_ptr );

The functions used to populate an object are:

add_property_long( return_value, property_name, l ) - Add a property named 'property_name', of type long, equal to 'l'
add_property_double( return_value, property_name, d ) - Same, only adds a double
add_property_string( return_value, property_name, str ) - Same, only adds a string
add_property_stringl( return_value, property_name, str, l ) - Same, only adds a string of length 'l'

Returning an array:

Call array_init(return_value).
Fill it up with values. The functions available for this purpose are listed below.

The functions used to populate an array are:

add_assoc_long(return_value,key,l) - add associative entry with key 'key' and long value 'l'
add_assoc_double(return_value,key,d)
add_assoc_string(return_value,key,str,duplicate)
add_assoc_stringl(return_value,key,str,length,duplicate) specify the string length
add_index_long(return_value,index,l) - add entry in index 'index' with long value 'l'
add_index_double(return_value,index,d)
add_index_string(return_value,index,str)
add_index_stringl(return_value,index,str,length) - specify the string length
add_next_index_long(return_value,l) - add an array entry in the next free offset with long value 'l'
add_next_index_double(return_value,d)
add_next_index_string(return_value,str)
add_next_index_stringl(return_value,str,length) - specify the string length

Using the resource list

PHP has a standard way of dealing with various types of resources. This replaces all of the local linked lists in PHP 2.0.

Available functions:

php3_list_insert(ptr, type) - returns the 'id' of the newly inserted resource
php3_list_delete(id) - delete the resource with the specified id
php3_list_find(id,*type) - returns the pointer of the resource with the specified id, updates 'type' to the resource's type

Typically, these functions are used for SQL drivers but they can be used for anything else; for instance, maintaining file descriptors.

Typical list code would look like this:

Příklad E-7. Adding a new resource

RESOURCE *resource; /* ...allocate memory for resource and acquire resource... */ /* add a new resource to the list */ return_value->value.lval = php3_list_insert((void *) resource, LE_RESOURCE_TYPE); return_value->type = IS_LONG;

Příklad E-8. Using an existing resource

pval *resource_id; RESOURCE *resource; int type; convert_to_long(resource_id); resource = php3_list_find(resource_id->value.lval, &type); if (type != LE_RESOURCE_TYPE) { php3_error(E_WARNING,"resource index %d has the wrong type",resource_id->value.lval); RETURN_FALSE; } /* ...use resource... */

Příklad E-9. Deleting an existing resource

pval *resource_id; RESOURCE *resource; int type; convert_to_long(resource_id); php3_list_delete(resource_id->value.lval);
The resource types should be registered in php3_list.h, in enum list_entry_type. In addition, one should add shutdown code for any new resource type defined, in list.c's list_entry_destructor() (even if you don't have anything to do on shutdown, you must add an empty case).

Using the persistent resource table

PHP has a standard way of storing persistent resources (i.e., resources that are kept in between hits). The first module to use this feature was the MySQL module, and mSQL followed it, so one can get the general impression of how a persistent resource should be used by reading mysql.c. The functions you should look at are:

php3_mysql_do_connect

php3_mysql_connect()

php3_mysql_pconnect()

The general idea of persistence modules is this:

Code all of your module to work with the regular resource list mentioned in section (9).
Code extra connect functions that check if the resource already exists in the persistent resource list. If it does, register it as in the regular resource list as a pointer to the persistent resource list (because of 1., the rest of the code should work immediately). If it doesn't, then create it, add it to the persistent resource list AND add a pointer to it from the regular resource list, so all of the code would work since it's in the regular resource list, but on the next connect, the resource would be found in the persistent resource list and be used without having to recreate it. You should register these resources with a different type (e.g. LE_MYSQL_LINK for non-persistent link and LE_MYSQL_PLINK for a persistent link).

If you read mysql.c, you'll notice that except for the more complex connect function, nothing in the rest of the module has to be changed.

The very same interface exists for the regular resource list and the persistent resource list, only 'list' is replaced with 'plist':

php3_plist_insert(ptr, type) - returns the 'id' of the newly inserted resource
php3_plist_delete(id) - delete the resource with the specified id
php3_plist_find(id,*type) - returns the pointer of the resource with the specified id, updates 'type' to the resource's type

However, it's more than likely that these functions would prove to be useless for you when trying to implement a persistent module. Typically, one would want to use the fact that the persistent resource list is really a hash table. For instance, in the MySQL/mSQL modules, when there's a pconnect() call (persistent connect), the function builds a string out of the host/user/passwd that were passed to the function, and hashes the SQL link with this string as a key. The next time someone calls a pconnect() with the same host/user/passwd, the same key would be generated, and the function would find the SQL link in the persistent list.

Until further documented, you should look at mysql.c or msql.c to see how one should use the plist's hash table abilities.

One important thing to note: resources going into the persistent resource list must *NOT* be allocated with PHP's memory manager, i.e., they should NOT be created with emalloc(), estrdup(), etc. Rather, one should use the regular malloc(), strdup(), etc. The reason for this is simple - at the end of the request (end of the hit), every memory chunk that was allocated using PHP's memory manager is deleted. Since the persistent list isn't supposed to be erased at the end of a request, one mustn't use PHP's memory manager for allocating resources that go to it.

When you register a resource that's going to be in the persistent list, you should add destructors to it both in the non-persistent list and in the persistent list. The destructor in the non-persistent list destructor shouldn't do anything. The one in the persistent list destructor should properly free any resources obtained by that type (e.g. memory, SQL links, etc). Just like with the non-persistent resources, you *MUST* add destructors for every resource, even it requires no destruction and the destructor would be empty. Remember, since emalloc() and friends aren't to be used in conjunction with the persistent list, you mustn't use efree() here either.

Adding runtime configuration directives

Many of the features of PHP can be configured at runtime. These configuration directives can appear in either the designated php3.ini file, or in the case of the Apache module version in the Apache .conf files. The advantage of having them in the Apache .conf files is that they can be configured on a per-directory basis. This means that one directory may have a certain safemodeexecdir for example, while another directory may have another. This configuration granularity is especially handy when a server supports multiple virtual hosts.

The steps required to add a new directive:

Add directive to php3_ini_structure struct in mod_php3.h.
In main.c, edit the php3_module_startup function and add the appropriate cfg_get_string() or cfg_get_long() call.
Add the directive, restrictions and a comment to the php3_commands structure in mod_php3.c. Note the restrictions part. RSRC_CONF are directives that can only be present in the actual Apache .conf files. Any OR_OPTIONS directives can be present anywhere, include normal .htaccess files.
In either php3take1handler() or php3flaghandler() add the appropriate entry for your directive.
In the configuration section of the _php3_info() function in functions/info.c you need to add your new directive.
And last, you of course have to use your new directive somewhere. It will be addressable as php3_ini.directive.

Calling User Functions

To call user functions from an internal function, you should use the call_user_function() function.

call_user_function() returns SUCCESS on success, and FAILURE in case the function cannot be found. You should check that return value! If it returns SUCCESS, you are responsible for destroying the retval pval yourself (or return it as the return value of your function). If it returns FAILURE, the value of retval is undefined, and you mustn't touch it.

All internal functions that call user functions must be reentrant. Among other things, this means they must not use globals or static variables.

call_user_function() takes six arguments:

HashTable *function_table

This is the hash table in which the function is to be looked up.

pval *object

This is a pointer to an object on which the function is invoked. This should be NULL if a global function is called. If it's not NULL (i.e. it points to an object), the function_table argument is ignored, and instead taken from the object's hash. The object *may* be modified by the function that is invoked on it (that function will have access to it via $this). If for some reason you don't want that to happen, send a copy of the object instead.

pval *function_name

The name of the function to call. Must be a pval of type IS_STRING with function_name.str.val and function_name.str.len set to the appropriate values. The function_name is modified by call_user_function() - it's converted to lowercase. If you need to preserve the case, send a copy of the function name instead.

pval *retval

A pointer to a pval structure, into which the return value of the invoked function is saved. The structure must be previously allocated - call_user_function() does NOT allocate it by itself.

int param_count

The number of parameters being passed to the function.

pval *params[]

An array of pointers to values that will be passed as arguments to the function, the first argument being in offset 0, the second in offset 1, etc. The array is an array of pointers to pval's; The pointers are sent as-is to the function, which means if the function modifies its arguments, the original values are changed (passing by reference). If you don't want that behavior, pass a copy instead.

Reporting Errors

To report errors from an internal function, you should call the php3_error() function. This takes at least two parameters -- the first is the level of the error, the second is the format string for the error message (as in a standard printf() call), and any following arguments are the parameters for the format string. The error levels are:

E_NOTICE

Notices are not printed by default, and indicate that the script encountered something that could indicate an error, but could also happen in the normal course of running a script. For example, trying to access the value of a variable which has not been set, or calling stat() on a file that doesn't exist.

E_WARNING

Warnings are printed by default, but do not interrupt script execution. These indicate a problem that should have been trapped by the script before the call was made. For example, calling ereg() with an invalid regular expression.

E_ERROR

Errors are also printed by default, and execution of the script is halted after the function returns. These indicate errors that can not be recovered from, such as a memory allocation problem.

E_PARSE

Parse errors should only be generated by the parser. The code is listed here only for the sake of completeness.

E_CORE_ERROR

This is like an E_ERROR, except it is generated by the core of PHP. Functions should not generate this type of error.

E_CORE_WARNING

This is like an E_WARNING, except it is generated by the core of PHP. Functions should not generate this type of error.

E_COMPILE_ERROR

This is like an E_ERROR, except it is generated by the Zend Scripting Engine. Functions should not generate this type of error.

E_COMPILE_WARNING

This is like an E_WARNING, except it is generated by the Zend Scripting Engine. Functions should not generate this type of error.

E_USER_ERROR

This is like an E_ERROR, except it is generated in PHP code by using the PHP function trigger_error(). Functions should not generate this type of error.

E_USER_WARNING

This is like an E_WARNING, except it is generated by using the PHP function trigger_error(). Functions should not generate this type of error.

E_USER_NOTICE

This is like an E_NOTICE, except it is generated by using the PHP function trigger_error(). Functions should not generate this type of error.

E_ALL

All of the above. Using this error_reporting level will show all error types.

Příloha F. Seznam aliasů funkcí

Toto je seznam aliasů. Všechny aliasy jsou zde uvedeny. Obvykle je špatným nápadem používat aliasy, mohou být spojeny s obsolentní nebo přejmenovanou funkcí, což povede k neportovatelnému skriptu. Tento seznam je poskytován proto, aby pomohl těm, kdo chtějí upgradovat své staré skripty na novou syntaxi.

Některé funkce mohou mít dva názvy a žádný není preferován (např. is_int() a is_integer() jsou rovnocenné)

Tento seznam je konzistentní s PHP 4.0.6.

Tabulka F-1. Aliasy

Alias	Základní funkce	Použité rozšíření
add	swfmovie_add()	Ming (flash)
add	swfsprite_add()	Ming (flash)
add_root	domxml_add_root()	DOM XML
addaction	swfbutton_addAction()	Ming (flash)
addcolor	swfdisplayitem_addColor()	Ming (flash)
addentry	swfgradient_addEntry()	Ming (flash)
addfill	swfshape_addfill()	Ming (flash)
addshape	swfbutton_addShape()	Ming (flash)
addstring	swftext_addString()	Ming (flash)
addstring	swftextfield_addString()	Ming (flash)
align	swftextfield_align()	Ming (flash)
attributes	domxml_attributes()	DOM XML
children	domxml_children()	DOM XML
chop	rtrim()	Base syntax
close	closedir()	Base syntax
com_get	com_propget()	COM
com_propset	com_propput()	COM
com_set	com_propput()	COM
cv_add	ccvs_add()	CCVS
cv_auth	ccvs_auth()	CCVS
cv_command	ccvs_command()	CCVS
cv_count	ccvs_count()	CCVS
cv_delete	ccvs_delete()	CCVS
cv_done	ccvs_done()	CCVS
cv_init	ccvs_init()	CCVS
cv_lookup	ccvs_lookup()	CCVS
cv_new	ccvs_new()	CCVS
cv_report	ccvs_report()	CCVS
cv_return	ccvs_return()	CCVS
cv_reverse	ccvs_reverse()	CCVS
cv_sale	ccvs_sale()	CCVS
cv_status	ccvs_status()	CCVS
cv_textvalue	ccvs_textvalue()	CCVS
cv_void	ccvs_void()	CCVS
die	exit()	Ostatní funkce
dir	getdir()	Základní syntaxe
diskfreespace	disk_free_space()	Filesystém
domxml_getattr	domxml_get_attribute()	DOM XML
domxml_setattr	domxml_set_attribute()	DOM XML
doubleval	floatval()	Base syntax
drawarc	swfshape_drawarc()	Ming (flash)
drawcircle	swfshape_drawcircle()	Ming (flash)
drawcubic	swfshape_drawcubic()	Ming (flash)
drawcubicto	swfshape_drawcubicto()	Ming (flash)
drawcurve	swfshape_drawcurve()	Ming (flash)
drawcurveto	swfshape_drawcurveto()	Ming (flash)
drawglyph	swfshape_drawglyph()	Ming (flash)
drawline	swfshape_drawline()	Ming (flash)
drawlineto	swfshape_drawlineto()	Ming (flash)
dtd	domxml_intdtd()	DOM XML
dumpmem	domxml_dumpmem()	DOM XML
fbsql	fbsql_db_query()	FrontBase
fputs	fwrite()	Base syntax
get_attribute	domxml_get_attribute()	DOM XML
getascent	swffont_getAscent()	Ming (flash)
getascent	swftext_getAscent()	Ming (flash)
getattr	domxml_get_attribute()	DOM XML
getdescent	swffont_getDescent()	Ming (flash)
getdescent	swftext_getDescent()	Ming (flash)
getheight	swfbitmap_getHeight()	Ming (flash)
getleading	swffont_getLeading()	Ming (flash)
getleading	swftext_getLeading()	Ming (flash)
getshape1	swfmorph_getShape1()	Ming (flash)
getshape2	swfmorph_getShape2()	Ming (flash)
getwidth	swfbitmap_getWidth()	Ming (flash)
getwidth	swffont_getWidth()	Ming (flash)
getwidth	swftext_getWidth()	Ming (flash)
gzputs	gzwrite()	Zlib
i18n_convert	mb_convert_encoding()	Multi-bytes Strings
i18n_discover_encoding	mb_detect_encoding()	Multi-bytes Strings
i18n_http_input	mb_http_input()	Multi-bytes Strings
i18n_http_output	mb_http_output()	Multi-bytes Strings
i18n_internal_encoding	mb_internal_encoding()	Multi-bytes Strings
i18n_ja_jp_hantozen	mb_convert_kana()	Multi-bytes Strings
i18n_mime_header_decode	mb_decode_mimeheader()	Multi-bytes Strings
i18n_mime_header_encode	mb_encode_mimeheader()	Multi-bytes Strings
imap_create	imap_createmailbox()	IMAP
imap_fetchtext	imap_body()	IMAP
imap_getmailboxes	imap_list_full()	IMAP
imap_getsubscribed	imap_lsub_full()	IMAP
imap_header	imap_headerinfo()	IMAP
imap_listmailbox	imap_list()	IMAP
imap_listsubscribed	imap_lsub()	IMAP
imap_rename	imap_renamemailbox()	IMAP
imap_scan	imap_listscan()	IMAP
imap_scanmailbox	imap_listscan()	IMAP
ini_alter	ini_set()	Základní syntaxe
is_double	is_float()	Základní syntaxe
is_integer	is_int()	Základní syntaxe
is_long	is_int()	Základní syntaxe
is_real	is_float()	Základní syntaxe
is_writeable	is_writable()	Základní syntaxe
join	implode()	Základní syntaxe
labelframe	swfmovie_labelFrame()	Ming (flash)
labelframe	swfsprite_labelFrame()	Ming (flash)
last_child	domxml_last_child()	DOM XML
lastchild	domxml_last_child()	DOM XML
ldap_close	ldap_unbind()	LDAP
magic_quotes_runtime	set_magic_quotes_runtime()	Základní syntaxe
mbstrcut	mb_strcut()	Řetězce s vícebytovými znaky
mbstrlen	mb_strlen()	Řetězce s vícebytovými znaky
mbstrpos	mb_strpos()	Řetězce s vícebytovými znaky
mbstrrpos	mb_strrpos()	Řetězce s vícebytovými znaky
mbsubstr	mb_substr()	Řetězce s vícebytovými znaky
ming_setcubicthreshold	ming_setCubicThreshold()	Ming (flash)
ming_setscale	ming_setScale()	Ming (flash)
move	swfdisplayitem_move()	Ming (flash)
movepen	swfshape_movepen()	Ming (flash)
movepento	swfshape_movepento()	Ming (flash)
moveto	swfdisplayitem_moveTo()	Ming (flash)
moveto	swffill_moveTo()	Ming (flash)
moveto	swftext_moveTo()	Ming (flash)
msql	msql_db_query()	mSQL
msql_affected_rows	msql_affected_rows()	mSQL
msql_createdb	msql_create_db()	mSQL
msql_dbname	msql_result()	mSQL
msql_dropdb	msql_drop_db()	mSQL
msql_fieldflags	msql_field_flags()	mSQL
msql_fieldlen	msql_field_len()	mSQL
msql_fieldname	msql_field_name()	mSQL
msql_fieldtable	msql_field_table()	mSQL
msql_fieldtype	msql_field_type()	mSQL
msql_freeresult	msql_free_result()	mSQL
msql_listdbs	msql_list_dbs()	mSQL
msql_listfields	msql_list_fields()	mSQL
msql_listtables	msql_list_tables()	mSQL
msql_numfields	msql_num_fields()	mSQL
msql_numrows	msql_num_rows()	mSQL
msql_regcase	sql_regcase()	mSQL
msql_selectdb	msql_select_db()	mSQL
msql_tablename	msql_result()	mSQL
mssql_affected_rows	sybase_affected_rows()	Sybase
mssql_affected_rows	sybase_affected_rows()	Sybase
mssql_close	sybase_close()	Sybase
mssql_close	sybase_close()	Sybase
mssql_connect	sybase_connect()	Sybase
mssql_connect	sybase_connect()	Sybase
mssql_data_seek	sybase_data_seek()	Sybase
mssql_data_seek	sybase_data_seek()	Sybase
mssql_fetch_array	sybase_fetch_array()	Sybase
mssql_fetch_array	sybase_fetch_array()	Sybase
mssql_fetch_field	sybase_fetch_field()	Sybase
mssql_fetch_field	sybase_fetch_field()	Sybase
mssql_fetch_object	sybase_fetch_object()	Sybase
mssql_fetch_object	sybase_fetch_object()	Sybase
mssql_fetch_row	sybase_fetch_row()	Sybase
mssql_fetch_row	sybase_fetch_row()	Sybase
mssql_field_seek	sybase_field_seek()	Sybase
mssql_field_seek	sybase_field_seek()	Sybase
mssql_free_result	sybase_free_result()	Sybase
mssql_free_result	sybase_free_result()	Sybase
mssql_get_last_message	sybase_get_last_message()	Sybase
mssql_get_last_message	sybase_get_last_message()	Sybase
mssql_min_client_severity	sybase_min_client_severity()	Sybase
mssql_min_error_severity	sybase_min_error_severity()	Sybase
mssql_min_message_severity	sybase_min_message_severity()	Sybase
mssql_min_server_severity	sybase_min_server_severity()	Sybase
mssql_num_fields	sybase_num_fields()	Sybase
mssql_num_fields	sybase_num_fields()	Sybase
mssql_num_rows	sybase_num_rows()	Sybase
mssql_num_rows	sybase_num_rows()	Sybase
mssql_pconnect	sybase_pconnect()	Sybase
mssql_pconnect	sybase_pconnect()	Sybase
mssql_query	sybase_query()	Sybase
mssql_query	sybase_query()	Sybase
mssql_result	sybase_result()	Sybase
mssql_result	sybase_result()	Sybase
mssql_select_db	sybase_select_db()	Sybase
mssql_select_db	sybase_select_db()	Sybase
multcolor	swfdisplayitem_multColor()	Ming (flash)
mysql	mysql_db_query()	MySQL
mysql_createdb	mysql_create_db()	MySQL
mysql_db_name	mysql_result()	MySQL
mysql_dbname	mysql_result()	MySQL
mysql_dropdb	mysql_drop_db()	MySQL
mysql_fieldflags	mysql_field_flags()	MySQL
mysql_fieldlen	mysql_field_len()	MySQL
mysql_fieldname	mysql_field_name()	MySQL
mysql_fieldtable	mysql_field_table()	MySQL
mysql_fieldtype	mysql_field_type()	MySQL
mysql_freeresult	mysql_free_result()	MySQL
mysql_listdbs	mysql_list_dbs()	MySQL
mysql_listfields	mysql_list_fields()	MySQL
mysql_listtables	mysql_list_tables()	MySQL
mysql_numfields	mysql_num_fields()	MySQL
mysql_numrows	mysql_num_rows()	MySQL
mysql_selectdb	mysql_select_db()	MySQL
mysql_tablename	mysql_result()	MySQL
name	domxml_attrname()	DOM XML
new_child	domxml_new_child()	DOM XML
new_xmldoc	domxml_new_xmldoc()	DOM XML
nextframe	swfmovie_nextFrame()	Ming (flash)
nextframe	swfsprite_nextFrame()	Ming (flash)
node	domxml_node()	DOM XML
oci8append	ocicollappend()	OCI8
oci8assign	ocicollassign()	OCI8
oci8assignelem	ocicollassignelem()	OCI8
oci8close	ocicloselob()	OCI8
oci8free	ocifreecoll()	OCI8
oci8free	ocifreedesc()	OCI8
oci8getelem	ocicollgetelem()	OCI8
oci8load	ociloadlob()	OCI8
oci8max	ocicollmax()	OCI8
oci8ocifreecursor	ocifreestatement()	OCI8
oci8save	ocisavelob()	OCI8
oci8savefile	ocisavelobfile()	OCI8
oci8size	ocicollsize()	OCI8
oci8trim	ocicolltrim()	OCI8
oci8writetemporary	ociwritetemporarylob()	OCI8
oci8writetofile	ociwritelobtofile()	OCI8
odbc_do	odbc_exec()	OCI8
odbc_field_precision	odbc_field_len()	OCI8
orbit_caught_exception	satellite_caught_exception()	Satellite
orbit_exception_id	satellite_exception_id()	Satellite
orbit_exception_value	satellite_exception_value()	Satellite
orbit_get_repository_id	satellite_get_repository_id()	Satellite
orbit_load_idl	satellite_load_idl()	Satellite
output	swfmovie_output()	Ming (flash)
parent	domxml_parent()	DOM XML
pdf_add_outline	pdf_add_bookmark()	PDF
pg_clientencoding	pg_client_encoding()	PostgreSQL
pg_setclientencoding	pg_set_client_encoding()	PostgreSQL
pos	current()	Base syntax
recode	recode_string()	Recode
remove	swfmovie_remove()	Ming (flash)
remove	swfsprite_remove()	Ming (flash)
rewind	rewinddir()	Base syntax
root	domxml_root()	DOM XML
rotate	swfdisplayitem_rotate()	Ming (flash)
rotateto	swfdisplayitem_rotateTo()	Ming (flash)
rotateto	swffill_rotateTo()	Ming (flash)
save	swfmovie_save()	Ming (flash)
savetofile	swfmovie_saveToFile()	Ming (flash)
scale	swfdisplayitem_scale()	Ming (flash)
scaleto	swfdisplayitem_scaleTo()	Ming (flash)
scaleto	swffill_scaleTo()	Ming (flash)
set_attribute	domxml_set_attribute()	DOM XML
set_content	domxml_set_content()	DOM XML
setaction	swfbutton_setAction()	Ming (flash)
setattr	domxml_set_attribute()	DOM XML
setbackground	swfmovie_setBackground()	Ming (flash)
setbounds	swftextfield_setBounds()	Ming (flash)
setcolor	swftext_setColor()	Ming (flash)
setcolor	swftextfield_setColor()	Ming (flash)
setdepth	swfdisplayitem_setDepth()	Ming (flash)
setdimension	swfmovie_setDimension()	Ming (flash)
setdown	swfbutton_setDown()	Ming (flash)
setfont	swftext_setFont()	Ming (flash)
setfont	swftextfield_setFont()	Ming (flash)
setframes	swfmovie_setFrames()	Ming (flash)
setframes	swfsprite_setFrames()	Ming (flash)
setheight	swftext_setHeight()	Ming (flash)
setheight	swftextfield_setHeight()	Ming (flash)
sethit	swfbutton_setHit()	Ming (flash)
setindentation	swftextfield_setIndentation()	Ming (flash)
setleftfill	swfshape_setleftfill()	Ming (flash)
setleftmargin	swftextfield_setLeftMargin()	Ming (flash)
setline	swfshape_setline()	Ming (flash)
setlinespacing	swftextfield_setLineSpacing()	Ming (flash)
setmargins	swftextfield_setMargins()	Ming (flash)
setmatrix	swfdisplayitem_setMatrix()	Ming (flash)
setname	swfdisplayitem_setName()	Ming (flash)
setname	swftextfield_setName()	Ming (flash)
setover	swfbutton_setOver()	Ming (flash)
setrate	swfmovie_setRate()	Ming (flash)
setratio	swfdisplayitem_setRatio()	Ming (flash)
setrightfill	swfshape_setrightfill()	Ming (flash)
setrightmargin	swftextfield_setRightMargin()	Ming (flash)
setspacing	swftext_setSpacing()	Ming (flash)
setup	swfbutton_setUp()	Ming (flash)
show_source	highlight_file ()	Základní syntaxe
sizeof	count()	Základní syntaxe
skewx	swfdisplayitem_skewX()	Ming (flash)
skewxto	swfdisplayitem_skewXTo()	Ming (flash)
skewxto	swffill_skewXTo()	Ming (flash)
skewy	swfdisplayitem_skewY()	Ming (flash)
skewyto	swfdisplayitem_skewYTo()	Ming (flash)
skewyto	swffill_skewYTo()	Ming (flash)
snmpwalkoid	snmprealwalk()	SNMP
strchr	strstr()	Základní syntaxe
streammp3	swfmovie_streamMp3()	Ming (flash)
swfaction	swfaction_init()	Ming (flash)
swfbitmap	swfbitmap_init()	Ming (flash)
swfbutton	swfbutton_init()	Ming (flash)
swfbutton_keypress	swfbutton_keypress()	Ming (flash)
swffill	swffill_init()	Ming (flash)
swffont	swffont_init()	Ming (flash)
swfgradient	swfgradient_init()	Ming (flash)
swfmorph	swfmorph_init()	Ming (flash)
swfmovie	swfmovie_init()	Ming (flash)
swfshape	swfshape_init()	Ming (flash)
swfsprite	swfsprite_init()	Ming (flash)
swftext	swftext_init()	Ming (flash)
swftextfield	swftextfield_init()	Ming (flash)
unlink	domxml_unlink_node()	DOM XML
xpath_eval	xpath_eval()	DOM XML
xpath_eval_expression	xpath_eval_expression()	DOM XML
xpath_init	xpath_init()	DOM XML
xpath_new_context	xpath_new_context()	DOM XML
xptr_new_context	xpath_new_context()	DOM XML

Příloha G. Seznam vyhrazených slov

Toto je seznam vyhrazených slov PHP, obvykle konstant a předdefinovaných proměnných. Nenajdete zde žádné funkce, což však neplatí pro jazykové konstrukty. Uvedenými názvy byste se neměli pokoušet nazývat proměnné, funkce, konstanty nebo metody, vedlo by to spolehlivě ke zmatku.

and	E_PARSE	old_function
$argv	E_ERROR	or
as	E_WARNING	parent
$argc	eval	PHP_OS
break	exit()	$PHP_SELF
case	extends	PHP_VERSION
cfunction	`FALSE`	print()
class	for	require()
continue	foreach	require_once()
declare	function	return()
default	$HTTP_COOKIE_VARS	static
do	$HTTP_GET_VARS	switch
die()	$HTTP_POST_VARS	stdClass
echo()	$HTTP_POST_FILES	$this
else	$HTTP_ENV_VARS	`TRUE`
elseif	$HTTP_SERVER_VARS	var
empty()	if	xor
enddeclare	include()	virtual()
endfor	include_once()	while
endforeach	global	__FILE__
endif	list()	__LINE__
endswitch	new	__sleep
endwhile	not	__wakeup
E_ALL	NULL

Příloha H. List of Resource Types

The following is a list of functions which create, use or destroy PHP resources. The function is_resource() can be used to determine if a variable is a resource and get_resource_type() will return the type of resource it is.

Tabulka H-1. Resource Types

Resource Type Name	Created By	Used By	Destroyed By	Definition
aspell	aspell_new()	aspell_check(), aspell_check_raw(), aspell_suggest()	None	Aspell dictionary
bzip2	bzopen()	bzerrno(), bzerror(), bzerrstr(), bzflush(), bzread(), bzwrite()	bzclose()	Bzip2 file
COM	com_load()	com_invoke(), com_propget(), com_get(), com_propput(), com_set(), com_propput()	None	COM object reference
VARIANT
cpdf	cpdf_open()	cpdf_page_init(), cpdf_finalize_page(), cpdf_finalize(), cpdf_output_buffer(), cpdf_save_to_file(), cpdf_set_current_page(), cpdf_begin_text(), cpdf_end_text(), cpdf_show(), cpdf_show_xy(), cpdf_text(), cpdf_set_font(), cpdf_set_leading(), cpdf_set_text_rendering(), cpdf_set_horiz_scaling(), cpdf_set_text_rise(), cpdf_set_text_matrix(), cpdf_set_text_pos(), cpdf_set_text_pos(), cpdf_set_word_spacing(), cpdf_continue_text(), cpdf_stringwidth(), cpdf_save(), cpdf_translate(), cpdf_restore(), cpdf_scale(), cpdf_rotate(), cpdf_setflat(), cpdf_setlinejoin(), cpdf_setlinecap(), cpdf_setmiterlimit(), cpdf_setlinewidth(), cpdf_setdash(), cpdf_moveto(), cpdf_rmoveto(), cpdf_curveto(), cpdf_lineto(), cpdf_rlineto(), cpdf_circle(), cpdf_arc(), cpdf_rect(), cpdf_closepath(), cpdf_stroke(), cpdf_closepath_fill_stroke(), cpdf_fill_stroke(), cpdf_clip(), cpdf_fill(), cpdf_setgray_fill(), cpdf_setgray_stroke(), cpdf_setgray(), cpdf_setrgbcolor_fill(), cpdf_setrgbcolor_stroke(), cpdf_setrgbcolor(), cpdf_add_outline(), cpdf_set_page_animation(), cpdf_import_jpeg(), cpdf_place_inline_image(), cpdf_add_annotation()	cpdf_close()	PDF document with CPDF lib
cpdf outline
curl	curl_init()	curl_init(), curl_exec()	curl_close()	Curl session
dbm	dbmopen()	dbmexists(), dbmfetch(), dbminsert(), dbmreplace(), dbmdelete(), dbmfirstkey(), dbmnextkey()	dbmclose()	Link to DBM database
dba	dba_open()	dba_delete(), dba_exists(), dba_fetch(), dba_firstkey(), dba_insert(), dba_nextkey(), dba_optimize(), dba_replace(), dba_sync()	dba_close()	Link to DBA base
dba persistent	dba_popen()	dba_delete(), dba_exists(), dba_fetch(), dba_firstkey(), dba_insert(), dba_nextkey(), dba_optimize(), dba_replace(), dba_sync()	None	Persistent link to DBA base
dbase	dbase_open()	dbase_pack(), dbase_add_record(), dbase_replace_record(), dbase_delete_record(), dbase_get_record(), dbase_get_record_with_names(), dbase_numfields(), dbase_numrecords()	dbase_close()	Link to Dbase base
dbx_link_object	dbx_connect()	dbx_query()	dbx_close()	dbx connection
dbx_result_object	dbx_query()	()	None	dbx result
domxml attribute
domxml document
domxml node
xpath context
xpath object
fbsql database	fbsql_select_db()	()	None	fbsql database
fbsql link	fbsql_change_user(), fbsql_connect()	fbsql_autocommit(), fbsql_change_user(), fbsql_create_db(), fbsql_data_seek(), fbsql_db_query(), fbsql_drop_db(), (), fbsql_select_db(), fbsql_errno(), fbsql_error(), fbsql_insert_id(), fbsql_list_dbs()	fbsql_close()	Link to fbsql database
fbsql plink	fbsql_change_user(), fbsql_pconnect()	fbsql_autocommit(), fbsql_change_user(), fbsql_create_db(), fbsql_data_seek(), fbsql_db_query(), fbsql_drop_db(), (), fbsql_select_db(), fbsql_errno(), fbsql_error(), fbsql_insert_id(), fbsql_list_dbs()	None	Persistent link to fbsql database
fbsql result	fbsql_db_query(), fbsql_list_dbs(), fbsql_query(), fbsql_list_fields(), fbsql_list_tables(), fbsql_tablename()	fbsql_affected_rows(), fbsql_fetch_array(), fbsql_fetch_assoc(), fbsql_fetch_field(), fbsql_fetch_lengths(), fbsql_fetch_object(), fbsql_fetch_row(), fbsql_field_flags(), fbsql_field_name(), fbsql_field_len(), fbsql_field_seek(), fbsql_field_table(), fbsql_field_type(), fbsql_next_result(), fbsql_num_fields(), fbsql_num_rows(), fbsql_result(), fbsql_num_rows()	fbsql_free_result()	fbsql result
fdf	fdf_open()	fdf_create(), fdf_save(), fdf_get_value(), fdf_set_value(), fdf_next_field_name(), fdf_set_ap(), fdf_set_status(), fdf_get_status(), fdf_set_file(), fdf_get_file(), fdf_set_flags(), fdf_set_opt(), fdf_set_submit_form_action(), fdf_set_javascript_action()	fdf_close()	FDF File
ftp	ftp_connect()	ftp_login(), ftp_pwd(), ftp_cdup(), ftp_chdir(), ftp_mkdir(), ftp_rmdir(), ftp_nlist(), ftp_rawlist(), ftp_systype(), ftp_pasv(), ftp_get(), ftp_fget(), ftp_put(), ftp_fput(), ftp_size(), ftp_mdtm(), ftp_rename(), ftp_delete(), ftp_site()	ftp_quit()	FTP stream
gd	imagecreate(), imagecreatefromgif(), imagecreatefromjpeg(), imagecreatefrompng(), imagecreatefromwbmp(), imagecreatefromstring(), imagecreatetruecolor()	imagearc(), imagechar(), imagecharup(), imagecolorallocate(), imagecolorat(), imagecolorclosest(), imagecolorexact(), imagecolorresolve(), imagegammacorrect(), imagegammacorrect(), imagecolorset(), imagecolorsforindex(), imagecolorstotal(), imagecolortransparent(), imagecopy(), imagecopyresized(), imagedashedline(), imagefill(), imagefilledpolygon(), imagefilledrectangle(), imagefilltoborder(), imagegif(), imagepng(), imagejpeg(), imagewbmp(), imageinterlace(), imageline(), imagepolygon(), imagepstext(), imagerectangle(), imagesetpixel(), imagestring(), imagestringup(), imagesx(), imagesy(), imagettftext(), imagefilledarc(), imageellipse(), imagefilledellipse(), imagecolorclosestalpha(), imagecolorexactalpha(), imagecolorresolvealpha(), imagecopymerge(), imagecopymergegray(), imagecopyresampled(), imagetruecolortopalette(), imagesetbrush(), imagesettile(), imagesetthickness()	imagedestroy()	GD Image
gd font	imageloadfont()	imagechar(), imagecharup(), imagefontheight()	None	Font for GD
gd PS encoding
gd PS font	imagepsloadfont()	imagepstext(), imagepsslantfont(), imagepsextendfont(), imagepsencodefont(), imagepsbbox()	imagepsfreefont()	PS font for GD
GMP integer	gmp_init()	gmp_intval(), gmp_strval(), gmp_add(), gmp_sub(), gmp_mul(), gmp_div_q(), gmp_div_r(), gmp_div_qr(), gmp_div(), gmp_mod(), gmp_divexact(), gmp_cmp(), gmp_neg(), gmp_abs(), gmp_sign(), gmp_fact(), gmp_sqrt(), gmp_sqrtrm(), gmp_perfect_square(), gmp_pow(), gmp_powm(), gmp_prob_prime(), gmp_gcd(), gmp_gcdext(), gmp_invert(), gmp_legendre(), gmp_jacobi(), gmp_random(), gmp_and(), gmp_or(), gmp_xor(), gmp_setbit(), gmp_clrbit(), gmp_scan0(), gmp_scan1(), gmp_popcount(), gmp_hamdist()	None	GMP Number
hyperwave document	hw_cp(), hw_docbyanchor(), hw_getremote(), hw_getremotechildren()	hw_children(), hw_childrenobj(), hw_getparents(), hw_getparentsobj(), hw_getchildcoll(), hw_getchildcollobj(), hw_getremote(), hw_getsrcbydestobj(), hw_getandlock(), hw_gettext(), hw_getobjectbyquerycoll(), hw_getobjectbyquerycollobj(), hw_getchilddoccoll(), hw_getchilddoccollobj(), hw_getanchors(), hw_getanchorsobj(), hw_inscoll(), hw_pipedocument(), hw_unlock()	hw_deleteobject()	Hyperwave object
hyperwave link	hw_connect()	hw_children(), hw_childrenobj(), hw_cp(), hw_deleteobject(), hw_docbyanchor(), hw_docbyanchorobj(), hw_errormsg(), hw_edittext(), hw_error(), hw_getparents(), hw_getparentsobj(), hw_getchildcoll(), hw_getchildcollobj(), hw_getremote(), hw_getremotechildren(), hw_getsrcbydestobj(), hw_getobject(), hw_getandlock(), hw_gettext(), hw_getobjectbyquery(), hw_getobjectbyqueryobj(), hw_getobjectbyquerycoll(), hw_getobjectbyquerycollobj(), hw_getchilddoccoll(), hw_getchilddoccollobj(), hw_getanchors(), hw_getanchorsobj(), hw_mv(), hw_incollections(), hw_info(), hw_inscoll(), hw_insdoc(), hw_insertdocument(), hw_insertobject(), hw_mapid(), hw_modifyobject(), hw_pipedocument(), hw_unlock(), hw_who(), hw_getusername()	hw_close(), hw_free_document()	Link to Hyperwave server
hyperwave link persistent	hw_pconnect()	hw_children(), hw_childrenobj(), hw_cp(), hw_deleteobject(), hw_docbyanchor(), hw_docbyanchorobj(), hw_errormsg(), hw_edittext(), hw_error(), hw_getparents(), hw_getparentsobj(), hw_getchildcoll(), hw_getchildcollobj(), hw_getremote(), hw_getremotechildren(), hw_getsrcbydestobj(), hw_getobject(), hw_getandlock(), hw_gettext(), hw_getobjectbyquery(), hw_getobjectbyqueryobj(), hw_getobjectbyquerycoll(), hw_getobjectbyquerycollobj(), hw_getchilddoccoll(), hw_getchilddoccollobj(), hw_getanchors(), hw_getanchorsobj(), hw_mv(), hw_incollections(), hw_info(), hw_inscoll(), hw_insdoc(), hw_insertdocument(), hw_insertobject(), hw_mapid(), hw_modifyobject(), hw_pipedocument(), hw_unlock(), hw_who(), hw_getusername()	None	Persistent link to Hyperwave server
icap	icap_open()	icap_fetch_event(), icap_list_events(), icap_store_event(), icap_snooze(), icap_list_alarms(), icap_delete_event()	icap_close()	Link to icap server
imap	imap_open()	imap_append(), imap_body(), imap_check(), imap_createmailbox(), imap_delete(), imap_deletemailbox(), imap_expunge(), imap_fetchbody(), imap_fetchstructure(), imap_headerinfo(), imap_header(), imap_headers(), imap_listmailbox(), imap_getmailboxes(), imap_get_quota(), imap_status(), imap_listsubscribed(), imap_set_quota(), imap_set_quota(), imap_getsubscribed(), imap_mail_copy(), imap_mail_move(), imap_num_msg(), imap_num_recent(), imap_ping(), imap_renamemailbox(), imap_reopen(), imap_subscribe(), imap_undelete(), imap_unsubscribe(), imap_scanmailbox(), imap_mailboxmsginfo(), imap_fetchheader(), imap_uid(), imap_msgno(), imap_search(), imap_fetch_overview()	imap_close()	Link to IMAP, POP3 server
imap chain persistent
imap persistent
ingres	ingres_connect()	ingres_query(), ingres_num_rows(), ingres_num_fields(), ingres_field_name(), ingres_field_type(), ingres_field_nullable(), ingres_field_length(), ingres_field_precision(), ingres_field_scale(), ingres_fetch_array(), ingres_fetch_row(), ingres_fetch_object(), ingres_rollback(), ingres_commit(), ingres_autocommit()	ingres_close()	Link to ingresII base
ingres persistent	ingres_pconnect()	ingres_query(), ingres_num_rows(), ingres_num_fields(), ingres_field_name(), ingres_field_type(), ingres_field_nullable(), ingres_field_length(), ingres_field_precision(), ingres_field_scale(), ingres_fetch_array(), ingres_fetch_row(), ingres_fetch_object(), ingres_rollback(), ingres_commit(), ingres_autocommit()	None	Persistent link to ingresII base
interbase blob
interbase link	ibase_connect()	ibase_query(), ibase_prepare(), ibase_trans()	ibase_close()	Link to Interbase database
interbase link persistent	ibase_pconnect()	ibase_query(), ibase_prepare(), ibase_trans()	None	Persistent link to Interbase database
interbase query	ibase_prepare()	ibase_execute()	ibase_free_query()	Interbase query
interbase result	ibase_query()	ibase_fetch_row(), ibase_fetch_object(), ibase_field_info(), ibase_num_fields()	ibase_free_result()	Interbase Result
interbase transaction	ibase_trans()	ibase_commit()	ibase_rollback()	Interbase transaction
java
ldap link	ldap_connect(), ldap_search()	ldap_count_entries(), ldap_first_attribute(), ldap_first_entry(), ldap_get_attributes(), ldap_get_dn(), ldap_get_entries(), ldap_get_values(), ldap_get_values_len(), ldap_next_attribute(), ldap_next_entry()	ldap_close()	ldap connection
ldap result	ldap_read()	ldap_add(), ldap_compare(), ldap_bind(), ldap_count_entries(), ldap_delete(), ldap_errno(), ldap_error(), ldap_first_attribute(), ldap_first_entry(), ldap_get_attributes(), ldap_get_dn(), ldap_get_entries(), ldap_get_values(), ldap_get_values_len(), ldap_get_option(), ldap_list(), ldap_modify(), ldap_mod_add(), ldap_mod_replace(), ldap_next_attribute(), ldap_next_entry(), ldap_mod_del(), ldap_set_option(), ldap_unbind()	ldap_free_result()	ldap search result
ldap result entry
mcal	mcal_open(), mcal_popen()	mcal_create_calendar(), mcal_rename_calendar(), mcal_rename_calendar(), mcal_delete_calendar(), mcal_fetch_event(), mcal_list_events(), mcal_append_event(), mcal_store_event(), mcal_delete_event(), mcal_list_alarms(), mcal_event_init(), mcal_event_set_category(), mcal_event_set_title(), mcal_event_set_description(), mcal_event_set_start(), mcal_event_set_end(), mcal_event_set_alarm(), mcal_event_set_class(), mcal_next_recurrence(), mcal_event_set_recur_none(), mcal_event_set_recur_daily(), mcal_event_set_recur_weekly(), mcal_event_set_recur_monthly_mday(), mcal_event_set_recur_monthly_wday(), mcal_event_set_recur_yearly(), mcal_fetch_current_stream_event(), mcal_event_add_attribute(), mcal_expunge()	mcal_close()	Link to calendar server
SWFAction
SWFBitmap
SWFButton
SWFDisplayItem
SWFFill
SWFFont
SWFGradient
SWFMorph
SWFMovie
SWFShape
SWFSprite
SWFText
SWFTextField
mnogosearch agent
mnogosearch result
msql link	msql_connect()	msql(), msql_create_db(), msql_createdb(), msql_drop_db(), msql_drop_db(), msql_select_db(), msql_select_db()	msql_close()	Link to mSQL database
msql link persistent	msql_pconnect()	msql(), msql_create_db(), msql_createdb(), msql_drop_db(), msql_drop_db(), msql_select_db(), msql_select_db()	None	Persistent link to mSQL
msql query	msql_query()	msql(), msql_affected_rows(), msql_data_seek(), msql_dbname(), msql_fetch_array(), msql_fetch_field(), msql_fetch_object(), msql_fetch_row(), msql_fieldname(), msql_field_seek(), msql_fieldtable(), msql_fieldtype(), msql_fieldflags(), msql_fieldlen(), msql_num_fields(), msql_num_rows(), msql_numfields(), msql_numrows(), msql_result()	msql_free_result(), msql_free_result()	mSQL result
mssql link	mssql_connect()	mssql_query(), mssql_select_db()	mssql_close()	Link to Microsft SQL Server database
mssql link persistent	mssql_pconnect()	mssql_query(), mssql_select_db()	None	Persistent link to Microsft SQL Server
mssql result	mssql_query()	mssql_data_seek(), mssql_fetch_array(), mssql_fetch_field(), mssql_fetch_object(), mssql_fetch_row(), mssql_field_length(), mssql_field_name(), mssql_field_seek(), mssql_field_type(), mssql_num_fields(), mssql_num_rows(), mssql_result()	mssql_free_result()	Microsft SQL Server result
mysql link	mysql_connect()	mysql_affected_rows(), mysql_change_user(), mysql_create_db(), mysql_data_seek(), mysql_db_name(), mysql_db_query(), mysql_drop_db(), mysql_errno(), mysql_error(), mysql_insert_id(), mysql_list_dbs(), mysql_list_fields(), mysql_list_tables(), mysql_query(), mysql_result(), mysql_select_db(), mysql_tablename(), mysql_get_host_info(), mysql_get_proto_info(), mysql_get_server_info()	mysql_close()	Link to MySQL database
mysql link persistent	mysql_pconnect()	mysql_affected_rows(), mysql_change_user(), mysql_create_db(), mysql_data_seek(), mysql_db_name(), mysql_db_query(), mysql_drop_db(), mysql_errno(), mysql_error(), mysql_insert_id(), mysql_list_dbs(), mysql_list_fields(), mysql_list_tables(), mysql_query(), mysql_result(), mysql_select_db(), mysql_tablename(), mysql_get_host_info(), mysql_get_proto_info(), mysql_get_server_info()	None	Persistent link to MySQL database
mysql result	mysql_db_query(), mysql_list_dbs(), mysql_list_fields(), mysql_list_tables(), mysql_query()	mysql_data_seek(), mysql_db_name(), mysql_fetch_array(), mysql_fetch_assoc(), mysql_fetch_field(), mysql_fetch_lengths(), mysql_fetch_object(), mysql_fetch_row(), mysql_fetch_row(), mysql_field_flags(), mysql_field_name(), mysql_field_len(), mysql_field_seek(), mysql_field_table(), mysql_field_type(), mysql_num_fields(), mysql_num_rows(), mysql_result(), mysql_tablename()	mysql_free_result()	MySQL result
oci8 collection
oci8 connection	ocilogon(), ociplogon(), ocinlogon()	ocicommit(), ociserverversion(), ocinewcursor(), ociparse(), ocierror()	ocilogoff()	Link to Oracle database
oci8 descriptor
oci8 server
oci8 session
oci8 statement	ocinewdescriptor()	ocirollback(), ocinewdescriptor(), ocirowcount(), ocidefinebyname(), ocibindbyname(), ociexecute(), ocinumcols(), ociresult(), ocifetch(), ocifetchinto(), ocifetchstatement(), ocicolumnisnull(), ocicolumnname(), ocicolumnsize(), ocicolumntype(), ocistatementtype(), ocierror()	ocifreestatement()	Oracle Cursor
odbc link	odbc_connect()	odbc_autocommit(), odbc_commit(), odbc_error(), odbc_errormsg(), odbc_exec(), odbc_tables(), odbc_tableprivileges(), odbc_do(), odbc_prepare(), odbc_columns(), odbc_columnprivileges(), odbc_procedurecolumns(), odbc_specialcolumns(), odbc_rollback(), odbc_setoption(), odbc_gettypeinfo(), odbc_primarykeys(), odbc_foreignkeys(), odbc_procedures(), odbc_statistics()	odbc_close()	Link to ODBC database
odbc link persistent	odbc_connect()	odbc_autocommit(), odbc_commit(), odbc_error(), odbc_errormsg(), odbc_exec(), odbc_tables(), odbc_tableprivileges(), odbc_do(), odbc_prepare(), odbc_columns(), odbc_columnprivileges(), odbc_procedurecolumns(), odbc_specialcolumns(), odbc_rollback(), odbc_setoption(), odbc_gettypeinfo(), odbc_primarykeys(), odbc_foreignkeys(), odbc_procedures(), odbc_statistics()	None	Persistent link to ODBC database
odbc result	odbc_prepare()	odbc_binmode(), odbc_cursor(), odbc_execute(), odbc_fetch_into(), odbc_fetch_row(), odbc_field_name(), odbc_field_num(), odbc_field_type(), odbc_field_len(), odbc_field_precision(), odbc_field_scale(), odbc_longreadlen(), odbc_num_fields(), odbc_num_rows(), odbc_result(), odbc_result_all(), odbc_setoption()	odbc_free_result()	ODBC result
birdstep link
birdstep result
OpenSSL key	openssl_get_privatekey(), openssl_get_publickey()	openssl_sign(), openssl_seal(), openssl_open(), openssl_verify()	openssl_free_key()	OpenSSL key
OpenSSL X.509	openssl_x509_read()	openssl_x509_parse(), openssl_x509_checkpurpose()	openssl_x509_free()	Public Key
oracle Cursor	ora_open()	ora_bind(), ora_columnname(), ora_columnsize(), ora_columntype(), ora_error(), ora_errorcode(), ora_exec(), ora_fetch(), ora_fetch_into(), ora_getcolumn(), ora_numcols(), ora_numrows(), ora_parse()	ora_close()	Oracle cursor
oracle link	ora_logon()	ora_do(), ora_error(), ora_errorcode(), ora_rollback(), ora_commitoff(), ora_commiton(), ora_open(), ora_commit()	ora_logoff()	Link to oracle database
oracle link persistent	ora_plogon()	ora_do(), ora_error(), ora_errorcode(), ora_rollback(), ora_commitoff(), ora_commiton(), ora_open(), ora_commit()	None	Persistent link to oracle database
pdf document	pdf_new()	pdf_add_bookmark(), pdf_add_launchlink(), pdf_add_locallink(), pdf_add_note(), pdf_add_pdflink(), pdf_add_weblink(), pdf_arc(), pdf_attach_file(), pdf_begin_page(), pdf_circle(), pdf_clip(), pdf_closepath(), pdf_closepath_fill_stroke(), pdf_closepath_stroke(), pdf_concat(), pdf_continue_text(), pdf_curveto(), pdf_end_page(), pdf_endpath(), pdf_fill(), pdf_fill_stroke(), pdf_findfont(), pdf_get_buffer(), pdf_get_image_height(), pdf_get_image_width(), pdf_get_parameter(), pdf_get_value(), pdf_lineto(), pdf_moveto(), pdf_open_ccitt(), pdf_open_file(), pdf_open_image_file(), pdf_place_image(), pdf_rect(), pdf_restore(), pdf_rotate(), pdf_save(), pdf_scale(), pdf_setdash(), pdf_setflat(), pdf_setfont(), pdf_setgray(), pdf_setgray_fill(), pdf_setgray_stroke(), pdf_setlinecap(), pdf_setlinejoin(), pdf_setlinewidth(), pdf_setmiterlimit(), pdf_setpolydash(), pdf_setrgbcolor(), pdf_setrgbcolor_fill(), pdf_setrgbcolor_stroke(), pdf_set_border_color(), pdf_set_border_dash(), pdf_set_border_style(), pdf_set_char_spacing(), pdf_set_duration(), pdf_set_font(), pdf_set_horiz_scaling(), pdf_set_parameter(), pdf_set_text_pos(), pdf_set_text_rendering(), pdf_set_value(), pdf_set_word_spacing(), pdf_show(), pdf_show_boxed(), pdf_show_xy(), pdf_skew(), pdf_stringwidth(), pdf_stroke(), pdf_translate(), pdf_open_memory_image()	pdf_close(), pdf_delete()	PDF document
pdf image	pdf_open_image(), pdf_open_image_file(), pdf_open_memory_image()	pdf_get_image_height(), pdf_get_image_width(), pdf_open_CCITT(), pdf_place_image()	pdf_close_image()	Image in PDF file
pdf object
pdf outline
pgsql large object	pg_lo_open()	pg_lo_open(), pg_lo_create(), pg_lo_read(), pg_lo_read_all(), pg_lo_seek(), pg_lo_tell(), pg_lo_unlink(), pg_lo_write()	pg_lo_close()	PostgreSQL Large Object
pgsql link	pg_connect()	pg_affected_rows(), pg_query(), pg_send_query(), pg_get_result(), pg_connection_busy(), pg_connection_reset(), pg_connection_status(), pg_last_error(), pg_last_notice(), pg_lo_create(), pg_lo_export(), pg_lo_import(), pg_lo_open(), pg_lo_unlink(), pg_host(), pg_port(), pg_dbname(), pg_options(), pg_copy_from(), pg_copy_to(), pg_end_copy(), pg_put_line(), pg_tty(), pg_trace(), pg_untrace(), pg_set_client_encoding(), pg_client_encoding(), pg_metadata(), pg_convert(), pg_insert(), pg_select(), pg_delete(), pg_update()	pg_close()	Link to PostgreSQL database
pgsql link persistent	pg_pconnect()	pg_affected_rows(), pg_query(), pg_send_query(), pg_get_result(), pg_connection_busy(), pg_connection_reset(), pg_connection_status(), pg_last_error(), pg_last_notice(), pg_lo_create(), pg_lo_export(), pg_lo_import(), pg_lo_open(), pg_lo_unlink(), pg_host(), pg_port(), pg_dbname(), pg_options(), pg_copy_from(), pg_copy_to(), pg_end_copy(), pg_put_line(), pg_tty(), pg_trace(), pg_untrace(), pg_set_client_encoding(), pg_client_encoding(), pg_metadata(), pg_convert(), pg_insert(), pg_select(), pg_delete(), pg_update()	None	Persistent link to PostgreSQL database
pgsql result	pg_query(), pg_get_result()	pg_fetch_array(), pg_fetch_object(), pg_fetch_result(), pg_fetch_row(), pg_field_is_null(), pg_field_name(), pg_field_num(), pg_field_prtlen(), pg_field_size(), pg_field_type(), pg_last_oid(), pg_num_fields(), pg_num_rows(), pg_result_error(), pg_result_status()	pg_free_result()	PostgreSQL result
pgsql string
printer
printer brush
printer font
printer pen
pspell	pspell_new(), pspell_new_config(), pspell_new_personal()	pspell_add_to_personal(), pspell_add_to_session(), pspell_check(), pspell_clear_session(), pspell_config_ignore(), pspell_config_mode(), pspell_config_personal(), pspell_config_repl(), pspell_config_runtogether(), pspell_config_save_repl(), pspell_save_wordlist(), pspell_store_replacement(), pspell_suggest()	None	pspell dictionary
pspell config	pspell_config_create()	pspell_new_config()	None	pspell configuration
Sablotron XSLT	xslt_create()	xslt_closelog(), xslt_openlog(), xslt_run(), xslt_set_sax_handler(), xslt_errno(), xslt_error(), xslt_fetch_result(), xslt_free()	xslt_free()	XSLT parser
shmop	shmop_open()	shmop_read(), shmop_write(), shmop_size(), shmop_delete()	shmop_close()
sockets file descriptor set	socket()	accept_connect(), bind(), connect(), listen(), read(), write()	close()	Socket
sockets i/o vector
dir	dir()	readdir(), rewinddir()	closedir()	Dir handle
file	fopen()	feof(), fflush(), fgetc(), fgetcsv(), fgets(), fgetss(), flock(), fpassthru(), fputs(), fwrite(), fread(), fseek(), ftell(), fstat(), ftruncate(), set_file_buffer(), rewind()	fclose()	File handle
pipe	popen()	feof(), fflush(), fgetc(), fgetcsv(), fgets(), fgetss(), fpassthru(), fputs(), fwrite(), fread()	pclose()	Process handle
socket	fsockopen()	fflush(), fgetc(), fgetcsv(), fgets(), fgetss(), fpassthru(), fputs(), fwrite(), fread()	fclose()	Socket handle
stream
sybase-db link	sybase_connect()	sybase_query(), sybase_select_db()	sybase_close()	Link to Sybase database using DB library
sybase-db link persistent	sybase_pconnect()	sybase_query(), sybase_select_db()	None	Persistent link to Sybase database using DB library
sybase-db result	sybase_query()	sybase_data_seek(), sybase_fetch_array(), sybase_fetch_field(), sybase_fetch_object(), sybase_fetch_row(), sybase_field_seek(), sybase_num_fields(), sybase_num_rows(), sybase_result()	sybase_free_result()	Sybase result using DB library
sybase-ct link	sybase_connect()	sybase_affected_rows(), sybase_query(), sybase_select_db()	sybase_close()	Link to Sybase database using CT library
sybase-ct link persistent	sybase_pconnect()	sybase_affected_rows(), sybase_query(), sybase_select_db()	None	Persistent link to Sybase database using CT library
sybase-ct result	sybase_query()	sybase_data_seek(), sybase_fetch_array(), sybase_fetch_field(), sybase_fetch_object(), sybase_fetch_row(), sybase_field_seek(), sybase_num_fields(), sybase_num_rows(), sybase_result()	sybase_free_result()	Sybase result using CT library
sysvsem	sem_get()	sem_acquire()	sem_release()	System V Semaphore
sysvshm	shm_attach()	shm_remove(), shm_put_var(), shm_get_var(), shm_remove_var()	shm_detach()	System V Shared Memory
wddx	wddx_packet_start()	wddx_add_vars()	wddx_packet_end()	WDDX packet
xml	xml_parser_create()	xml_set_object(), xml_set_element_handler(), xml_set_character_data_handler(), xml_set_processing_instruction_handler(), xml_set_default_handler(), xml_set_unparsed_entity_decl_handler(), xml_set_notation_decl_handler(), xml_set_external_entity_ref_handler(), xml_parse(), xml_get_error_code(), xml_error_string(), xml_get_current_line_number(), xml_get_current_column_number(), xml_get_current_byte_index(), xml_parse_into_struct(), xml_parser_set_option(), xml_parser_get_option()	xml_parser_free()	XML parser
zlib	gzopen()	gzeof(), gzgetc(), gzgets(), gzgetss(), gzpassthru(), gzputs(), gzread(), gzrewind(), gzseek(), gztell(), gzwrite()	gzclose()	gz-compressed file

Příloha I. List of Parser Tokens

Various parts of the PHP language are represented internally by stuff like T_SR. PHP outputs identifiers like this one in parse errors, like "Parse error: unexpected T_SR, expecting ',' or ';' in script.php on line 10."

You're supposed to know that T_SR means >>. For everybody who doesn't know that, here is a table with those identifiers, PHP-syntax and references to the appropriate places in the manual.

Tabulka I-1. Tokens

Token	Syntax	Reference
T_AND_EQUAL	&=	assignment operators
T_ARRAY	array()	array(), array syntax
T_ARRAY_CAST	(array)	type-casting
T_AS	as	foreach
T_BAD_CHARACTER		anything below ASCII 32 except \t (0x09), \n (0x0a) and \r (0x0d)
T_BOOLEAN_AND	&&	logical operators
T_BOOLEAN_OR	\|\|	logical operators
T_BOOL_CAST	(bool) or (boolean)	type-casting
T_BREAK	break;	break
T_CASE	case	switch
T_CHARACTER
T_CLASS	class	classes and objects
T_CLOSE_TAG	?> or %>
T_COMMENT	// or #	comments
T_CONCAT_EQUAL	.=	assignment operators
T_CONST	const
T_CONSTANT_ENCAPSED_STRING	"foo" or 'bar'	string syntax
T_CONTINUE	continue
T_CURLY_OPEN
T_DEC	--	incrementing/decrementing operators
T_DECLARE	declare	declare
T_DEFAULT	default	switch
T_DIV_EQUAL	/=	assignment operators
T_DNUMBER	0.12, etc	floating point numbers
T_DO	do	do..while
T_DOLLAR_OPEN_CURLY_BRACES	${	complex variable parsed syntax
T_DOUBLE_ARROW	=>	array syntax
T_DOUBLE_CAST	(real), (double) or (float)	type-casting
T_ECHO	echo	echo()
T_ELSE	else	else
T_ELSEIF	elseif	elseif
T_EMPTY	empty	empty()
T_ENCAPSED_AND_WHITESPACE
T_ENDDECLARE	enddeclare	declare, alternative syntax
T_ENDFOR	endfor	for, alternative syntax
T_ENDFOREACH	endforeach	foreach, alternative syntax
T_ENDIF	endif	if, alternative syntax
T_ENDSWITCH	endswitch	switch, alternative syntax
T_ENDWHILE	endwhile	while, alternative syntax
T_END_HEREDOC		heredoc syntax
T_EVAL	eval()	eval()
T_EXIT	exit or die	exit(), die()
T_EXTENDS	extends	extends, classes and objects
T_FILE	__FILE__	constants
T_FOR	for	for
T_FOREACH	foreach	foreach
T_FUNCTION	function or cfunction	functions
T_GLOBAL	global	variable scope
T_IF	if	if
T_INC	++	incrementing/decrementing operators
T_INCLUDE	include()	include()
T_INCLUDE_ONCE	include_once()	include_once()
T_INLINE_HTML
T_INT_CAST	(int) or (integer)	type-casting
T_ISSET	isset()	isset()
T_IS_EQUAL	==	comparison operators
T_IS_GREATER_OR_EQUAL	>=	comparison operators
T_IS_IDENTICAL	===	comparison operators
T_IS_NOT_EQUAL	!= or <>	comparison operators
T_IS_NOT_IDENTICAL	!==	comparison operators
T_SMALLER_OR_EQUAL	<=	comparison operators
T_LINE	__LINE__	constants
T_LIST	list()	list()
T_LNUMBER	123, 012, 0x1ac, etc	integers
T_LOGICAL_AND	and	logical operators
T_LOGICAL_OR	or	logical operators
T_LOGICAL_XOR	xor	logical operators
T_MINUS_EQUAL	-=	assignment operators
T_ML_COMMENT	/* and */	comments
T_MOD_EQUAL	%=	assignment operators
T_MUL_EQUAL	*=	assignment operators
T_NEW	new	classes and objects
T_NUM_STRING
T_OBJECT_CAST	(object)	type-casting
T_OBJECT_OPERATOR	->	classes and objects
T_OLD_FUNCTION	old_function	old_function
T_OPEN_TAG	<?php, <? or <%	escaping from HTML
T_OPEN_TAG_WITH_ECHO	<?= or <%=	escaping from HTML
T_OR_EQUAL	\|=	assignment operators
T_PAAMAYIM_NEKUDOTAYIM	::	::
T_PLUS_EQUAL	+=	assignment operators
T_PRINT	print()	print()
T_REQUIRE	require()	require()
T_REQUIRE_ONCE	require_once()	require_once()
T_RETURN	return	returing values
T_SL	<<	bitwise operators
T_SL_EQUAL	<<=	assignment operators
T_SR	>>	bitwise operators
T_SR_EQUAL	>>=	assignment operators
T_START_HEREDOC	<<<	heredoc syntax
T_STATIC	static	variable scope
T_STRING
T_STRING_CAST	(string)	type-casting
T_STRING_VARNAME
T_SWITCH	switch	switch
T_UNSET	unset()	unset()
T_UNSET_CAST	(unset)	(not documented; casts to `NULL`)
T_USE	use	(not implemented)
T_VAR	var	classes and objects
T_VARIABLE	$foo	variables
T_WHILE	while	while, do..while
T_WHITESPACE
T_XOR_EQUAL	^=	assignment operators
T_FUNC_C	__FUNCTION__	constants, since `PHP` 4.3.0
T_CLASS_C	__CLASS__	constants, since `PHP` 4.3.0

Příloha J. O tomto manuálu

Formáty

Tento PHP manuál je poskytován v různých formátech. Tyto formáty se dají rozdělit do dvou skupin: formáty pro prohlížení on-line a balíky pro stahování.

Poznámka: Někteří vydavatelé vydali tištěné verze tohoto manuálu. Žádné z nich nedoporučujeme, protože velmi rychle zastarávají.

Manuál můžete číst on-line na http://www.php.net/ a mnoha zrcadlech. Pro zajištění nejrychlejšího přístupu byste si měli vybrat zrcadlo umístěné nejblíže k vám. Můžete si prohlížet manuál v "holém" HTML formátu (vhodném pro tisk) nebo v HTML formátu integrujícím manuál do vzhledu a chování samotných stránek PHP.

Výhodou on-line manuálu před off-line formáty je integrace uživatelských poznámek. Samozřejmou nevýhodou je to, že při prohlížení musíte být on-line.

Existuje více off-line formátů manuálu a formát pro vás nejvhodnější závisí na tom, jaký operační systém používáte a na vašem osobním stylu čtení. Pro informaci o tom, jak je manuál generován v tolika formátech, si přečtěte sekci 'Jak generujeme formáty' v dodatcích.

Pro nejvíce platforem se hodí manuál v HTML a jako prostý text. HTML formát je poskytován jak jako jediný HTML soubor, tak jako balíček souborů podle jednotlivých sekcí (což ve výsledku znamená kolekci tisíců souborů). HTML a prostý text jsou poskytovány jako tar soubory zkomprimované pomocí bzip2.

Jiným populárním platformně nezávislým formátem, a také formátem nejvhodnějším pro tisk, je PDF (známý také jako Adobe Acrobat). Ale před stažením tohoto formátu a stisknutím tlačítka pro tisk ještě jedno varování: Manuál je skoro 2000 stránek dlouhý a stále se upravuje!

Poznámka: Pokud ještě nemáte program schopný zobrazit formát PDF, můžete si stáhnout Adobe Acrobat Reader.

Pro vlastníky handheldů (Palm kompatibilních) jsou ideální formáty Palm document a iSilo. Můžete si přinést svůj handheld na směnu a použít prohlížeč formátu DOC nebo iSilo k oprášení znalostí PHP nebo jako rychlou příručku.

Pro platformu Windows existuje verze Widows HTML Help pro použití s aplikací Windows HTML Help- Tato verze poskytuje fulltextové vyhledávání, úplný rejstřík a záložky. Mnoho populárních vývojových prostředí pro vývoj v PHP pod Windows také integruje tuto verzi dokumentace, což zajišťuje snadný přístup.

Poznámka: Projekt Visual Basic for Linux je ve stádiu plánování, bude zahrnovat vývoj aplikace CHM Creator and Viewer for Linux. Pokud se zajímáte o stav vývoje, podívejte se na SourceForge.net page.

O uživatelských poznámkách

Uživatelské poznámky hrají důležitou roli ve vývoji tohoto manuálu. Umožněním čtenářům manuálu přidávat příklady a další vysvětlení přímo z jejich prohlížeče jsme schopni zabudovat zpětnou vazbu do hlavního textu manuálu. A než jsou poznámky zpracovány, jsou vidět v podobě, v jaké je uživatelé poslali, v on-line (a některých off-line) formátech.

Poznámka: Uživatelské poznámky nejsou moderovány před jejich zobrazením on-line, takže kvalita textu nebo příkladů kódu a jejich věrohodnost nemohou být zaručeny (ne, že by byla zaručena kvalita nebo přesnost samotného manuálu).

Jak najít více informací o PHP

Tento manuál se nepokouší poskytovat instrukce o obecných programovacích technikách. Pokud jste úplně čerstvý programátor nebo stále ještě začátečník, může vám přijít obtížné naučit se programovat v PHP pouze podle tohoto manuálu. Můžete chtít hledat texty více orientované na začátečníky. Zde je seznam knih týkajících se PHP: http://www.php.net/books.php.

Existuje mnoho aktivních e-mailových diskusních skupin pro diskusi o všech aspektech programování v PHP. Pokud máte problém, pro který nmůžete najít řešení, mohl by vám pomoci někdo z těchto skupin. Seznam diskusních skupin najdete na http://www.php.net/support.php, stejně tak i odkazy na archivy těchto skupin a jiné on-line zdroje. Dále, na http://www.php.net/links.php je seznam stránek zaměřených na články, fóra a galerie kódu pro PHP.

Jak pomoci zlepšit dokumentaci

Jsou dvě cesty, jak můžete pomoci zlepšit tuto dokumentaci.

Pokud v manuálu najdete chyby (v kterémkoli jazyce), oznamte je prosím pomocí bug systému na http://bugs.php.net/. Klasifikujte chybu jako "Documentation Problem". Můžete také poslat problémy spojené s konkrétními manuálovými formáty zde.

Poznámka: Nezneužívejte prosím bug systém odesíláním žádostí o pomoc. Použijte namísto toho diskusní fórum nebo komunitní stránky, jak již bylo zmíněno.

Při přidávání poznámek můžete poskytnout dodatečné příklady a vysvětlení pro ostatní čtenáře. Avšak neposílejte prosím pomocí tohoto anotačního systému hlášení o chybách. O anotacích se můžete více dozvědět v části 'O uživatelských poznámkách' tohoto dodatku.

Jak generujeme formáty

Tento manuál je napsán v XML s použitím DocBook XML DTD, DSSSL (Document Style and Semantics Specification Language) pro formátování a experimentálně XSLT (Extensible Stylesheet Language Transformations) pro údržbu a formátování.

Použití XML jako zdrojového formátu nám dává možnost generovat mnoho výstupních formátů ze zdrojových souborů a udržovat pouze jediný zdrojový dokument pro všechny formáty. Nástroji použitými pro formátování HTML a TeX verzí jsou Jade, jehož autorem je James Clark, a The Modular DocBook Stylesheets kde je autorem Norman Walsh. Používáme Microsoft HTML Help Workshop ke generování formátu Windows HTML Help a, samozřejmě, PHP samotné pro dodatečné konverze a formátování.

Manuál si můžete stáhnout v různých jazycích a formátech, včetně prostého textu, prostého HTML, PDF, PalmPilot DOC, PalmPilot iSilo a Windows HTML Help, z http://www.php.net/docs.php. Manuály jsou automaticky aktualizovány, pokud se jejich text změní.

Více informací o stahování zdrojového kódu dokumentace v XML najdete na http://cvs.php.net/. Dokumentace je uložena v modulu phpdoc.

Adabas D	Ingres	Oracle (OCI7 and OCI8)
dBase	InterBase	Ovrimos
Empress	FrontBase	PostgreSQL
FilePro (read-only)	mSQL	Solid
Hyperwave	Direct MS-SQL	Sybase
IBM DB2	MySQL	Velocis
Informix	ODBC	Unix dbm

SQL Type	PHP Type
SMALLINT, INTEGER	integer
NUMERIC, DECIMAL, FLOAT, REAL, DOUBLE	float
DATE, TIME, TIMESTAMP	string
VARCHAR, CHARACTER	string

Manuál PHP

Sestavil

I. Začínáme

What is PHP?

What can PHP do?

What do I need?

Your first PHP-enabled page

Something Useful

Dealing with Forms

Using old code with new versions of PHP

What's next?

General Installation Considerations

Unix/HP-UX installs

Unix/Linux installs

Using Packages

Unix/Mac OS X installs

Using Packages

Compiling for OS X server

Compiling for MacOS X client

Unix/OpenBSD installs

Using Ports

Using Packages

Unix/Solaris installs

Required software

Using Packages

Installation on UNIX systems

Apache Module Quick Reference

Building

Installation on Windows systems

Windows InstallShield

Manual Installation Steps

Building from source

Preparations

Putting it all together

Compiling

Installation of Windows extensions

Servers-CGI/Commandline

Testing

Benchmarking

Using Variables

Servers-Apache

Details of installing PHP with Apache on Unix

Installing PHP on Windows with Apache 1.3.x

Servers-Caudium

Servers-fhttpd

Servers-IIS/PWS

Windows and PWS/IIS 3

Windows and PWS 4 or newer

Windows NT/2000/XP and IIS 4 or newer

Servers-Netscape and iPlanet

Installing PHP with Netscape on Sun Solaris

Installing PHP with Netscape on Windows

Servers-OmniHTTPd Server

OmniHTTPd 2.0b1 and up for Windows

Servers-Oreilly Website Pro

Oreilly Website Pro 2.5 and up for Windows

Servers-Xitami

Xitami for Windows

Servers-Other web servers

Problems?

Read the FAQ

Other problems

Bug reports

Complete list of configure options

Configure Options in PHP 4

Database options

Graphics options

Misc options

PHP options

Server options

XML options

The configuration file

General Configuration Directives

Safe Mode Configuration Directives

Debugger Configuration Directives

Extension Loading Directives

mSQL Configuration Directives

Postgres Configuration Directives

SESAM Configuration Directives

Sybase Configuration Directives

Why is `$foo[bar]` wrong?