PHP

PHP
PHP
PHP
PHP: Hypertext Preprocessor
Paradigm(s) imperative, object-oriented, Procedural, reflective
Appeared in 1995; 16 years ago (1995)[1]
Designed by Rasmus Lerdorf
Developer The PHP Group
Stable release 5.3.8 (August 23, 2011; 2 months ago (2011-08-23))
Preview release 5.4RC1 (November 11, 2011; 0 days ago (2011-11-11))
Typing discipline Dynamic, weak
Major implementations Zend Engine, Phalanger, Quercus, Project Zero, HipHop
Influenced by C, Perl, Java, C++, Tcl[1]
Implementation language C
OS Cross-platform
License PHP License
Usual filename extensions .php, .phtml .php4 .php3 .php5 .phps
Website php.net
Wikibooks logo PHP Programming at Wikibooks

PHP is a general-purpose server-side scripting language originally designed for web development to produce dynamic web pages. For this purpose, PHP code is embedded into the HTML source document and interpreted by a web server with a PHP processor module, which generates the web page document. It also has evolved to include a command-line interface capability and can be used in standalone graphical applications.[2] PHP can be deployed on most web servers and as a standalone interpreter, on almost every operating system and platform free of charge.[3] There is also commercial software such as RadPHP, a rapid application development framework for the PHP language. A competitor to Microsoft's Active Server Pages (ASP) server-side script engine[4] and similar languages, PHP is installed on more than 20 million websites and 1 million web servers.[5]

PHP was originally created by Rasmus Lerdorf in 1995. The main implementation of PHP is now produced by The PHP Group and serves as the de facto standard for PHP as there is no formal specification.[6] PHP is free software released under the PHP License which is incompatible with the GNU General Public License (GPL) due to restrictions on the usage of the term PHP.[7]

While PHP originally stood for "Personal Home Page", it is now said to stand for "PHP: Hypertext Preprocessor", a recursive acronym.[8]

Contents

History

Rasmus Lerdorf, who wrote the original Common Gateway Interface component, and Andi Gutmans and Zeev Suraski, who rewrote the parser that formed PHP 3

PHP development began in 1994 when the Danish/Greenlandic/Canadian programmer Rasmus Lerdorf initially created a set of Perl scripts he called "Personal Home Page Tools" to maintain his personal homepage. The scripts performed tasks such as displaying his résumé and recording his web-page traffic.[6][9][10] Lerdorf initially announced the release of PHP on the comp.infosystems.www.authoring.cgi Usenet discussion group on June 8, 1995.[11]

Zeev Suraski and Andi Gutmans, two Israeli developers at the Technion IIT, rewrote the parser in 1997 and formed the base of PHP 3, changing the language's name to the recursive initialism PHP: Hypertext Preprocessor.[6] Afterwards, public testing of PHP 3 began, and the official launch came in June 1998. Suraski and Gutmans then started a new rewrite of PHP's core, producing the Zend Engine in 1999.[12] They also founded Zend Technologies in Ramat Gan, Israel.[6]

In 2008 PHP 5 became the only stable version under development. Late static binding had been missing from PHP and was added in version 5.3.[13][14]

A new major version has been under development alongside PHP 5 for several years. This version was originally planned to be released as PHP 6 as a result of its significant changes, which included plans for full Unicode support. However, Unicode support took developers much longer to implement than originally thought, and the decision was made in March 2010[15] to move the project to a branch, with features still under development moved to trunk.

Changes in the new code include the removal of register_globals,[16] magic quotes, and safe mode.[17][18] The reason for the removals was that register_globals had opened security holes by intentionally allowing runtime data injection, and the use of magic quotes had an unpredictable nature. Instead, to escape characters, magic quotes may be replaced with the addslashes() function, or more appropriately an escape mechanism specific to the database vendor itself like mysql_real_escape_string() for MySQL. Functions that will be removed in future versions and have been deprecated in PHP 5.3 will produce a warning if used.[19]

Many high-profile open-source projects ceased to support PHP 4 in new code as of February 5, 2008, because of the GoPHP5 initiative,[20] provided by a consortium of PHP developers promoting the transition from PHP 4 to PHP 5.[21][22]

As of 2011 PHP does not have native support for Unicode or multibyte strings; Unicode support is under development for a future version of PHP and will allow strings as well as class-, method-, and function-names to contain non-ASCII characters.[23][24]

PHP interpreters are available on both 32-bit and 64-bit operating systems, but on Microsoft Windows the only official distribution is a 32-bit implementation, requiring Windows 32-bit compatibility mode while using Internet Information Services (IIS) on a 64-bit Windows platform. Experimental 64-bit versions of PHP 5.3.0 were briefly available for MS Windows, but have since been removed.[25]

Licensing

PHP is free software released under the PHP License, which insists that:[26]

 4. Products derived from this software may not be called "PHP", nor
    may "PHP" appear in their name, without prior written permission
    from group@php.net.  You may indicate that your software works in
    conjunction with PHP by saying "Foo for PHP" instead of calling
    it "PHP Foo" or "phpfoo"

This restriction on use of the name PHP makes it incompatible with the GNU General Public License (GPL).[27]

Release history

Meaning
Red Release no longer supported
Green Release still supported
Blue Future release
Major version Minor version Release date Notes
1 1.0.0 1995-06-08 Officially called "Personal Home Page Tools (PHP Tools)". This is the first use of the name "PHP".[6]
2 2.0.0 1997-11-01 Considered by its creator as the "fastest and simplest tool" for creating dynamic web pages.[6]
3 3.0.0 1998-06-06 Development moves from one person to multiple developers. Zeev Suraski and Andi Gutmans rewrite the base for this version.[6]
4 4.0.0 2000-05-22 Added more advanced two-stage parse/execute tag-parsing system called the Zend engine.[28]
4.1.0 2001-12-10 Introduced 'superglobals' ($_GET, $_POST, $_SESSION, etc.)[28]
4.2.0 2002-04-22 Disabled register_globals by default. Data received over the network is not inserted directly into the global namespace anymore, closing possible security holes in applications.[28]
4.3.0 2002-12-27 Introduced the CLI, in addition to the CGI.[28][29]
4.4.0 2005-07-11 Added man pages for phpize and php-config scripts.[28]
4.4.9 2008-08-07 Security enhancements and bug fixes. The last release of the PHP 4.4 series.[30][31]
5 5.0.0 2004-07-13 Zend Engine II with a new object model.[32]
5.1.0 2005-11-24 Performance improvements with introduction of compiler variables in re-engineered PHP Engine.[32]
5.2.0 2006-11-02 Enabled the filter extension by default. Native JSON support.[32]
5.2.17 2011-01-06 Fix of critical vulnerability connected to floating point.
5.3.0 2009-06-30 Namespace support; Late static bindings, Jump label (limited goto), Native closures, Native PHP archives (phar), garbage collection for circular references, improved Windows support, sqlite3, mysqlnd as a replacement for libmysql as underlying library for the extensions that work with MySQL, fileinfo as a replacement for mime_magic for better MIME support, the Internationalization extension, and deprecation of ereg extension.
5.3.1 2009-11-19 Over 100 bug fixes, some of which were security fixes.
5.3.2 2010-03-04 Includes a large number of bug fixes.
5.3.3 2010-07-22 Mainly bug and security fixes; FPM SAPI.
5.3.4 2010-12-10 Mainly bug and security fixes; improvements to FPM SAPI.
5.3.5 2011-01-06 Fix of critical vulnerability connected to floating point.
5.3.6 2011-03-10 Over 60 bug fixes that were reported in the previous version.
5.3.7 2011-08-18 This release focuses on improving the stability of the PHP 5.3.x branch with over 90 bug fixes, some of which are security related.
5.3.8 2011-08-23 This release fixes two issues introduced in the PHP 5.3.7 release.
5.4.0beta2 2011-10-26 Trait Support, Removed items: register_globals, safe_mode, allow_call_time_pass_reference, session_register(), session_unregister() and session_is_registered(). Several improvements to existing features.
6  ?.? No date set The development of PHP 6 has been delayed because the developers have decided the current approach to handling of instance unicode is not a good one, and are considering alternate ways in the next version of PHP. The updates that were intended for PHP 6 were added to PHP 5.3.0(namespace support, Late Static Bindings, lambda functions, closures, goto) and 5.4.0(traits, closure rebinding) instead.

Beginning on June 28th, 2011, the PHP Group began following a timeline for when new versions of PHP will be released. [33] Under this timeline, at least one release should occur every month. Every one year, a minor release should occur which can include new features. Every minor release should at least have 2 years of security and bug fixes, followed by at least 1 year of only security fixes, for a total of a 3 year release process for every minor release. No new features (unless small self contained) will be introduced into a minor release during the 3 year release process.

Usage

PHP is a general-purpose scripting language that is especially suited to server-side web development where PHP generally runs on a web server. Any PHP code in a requested file is executed by the PHP runtime, usually to create dynamic web page content or dynamic images used on web sites or elsewhere.[34] It can also be used for command-line scripting and client-side GUI applications. PHP can be deployed on most web servers, many operating systems and platforms, and can be used with many relational database management systems (RDBMS). It is available free of charge, and the PHP Group provides the complete source code for users to build, customize and extend for their own use.[3]

PHP acts primarily as a filter,[35] taking input from a file or stream containing text and/or PHP instructions and outputting another stream of data; most commonly the output will be HTML. Since PHP 4, the PHP parser compiles input to produce bytecode for processing by the Zend Engine, giving improved performance over its interpreter predecessor.[36]

Originally designed to create dynamic web pages, PHP now focuses mainly on server-side scripting,[37] and it is similar to other server-side scripting languages that provide dynamic content from a web server to a client, such as Microsoft's Asp.net, Sun Microsystems' JavaServer Pages,[38] and mod_perl. PHP has also attracted the development of many frameworks that provide building blocks and a design structure to promote rapid application development (RAD). Some of these include CakePHP, Symfony, CodeIgniter, and Zend Framework, offering features similar to other web application frameworks.

The LAMP architecture has become popular in the web industry as a way of deploying web applications. PHP is commonly used as the P in this bundle alongside Linux, Apache and MySQL, although the P may also refer to Python or Perl or some combination of the three. WAMP packages (Windows/ Apache_HTTP_Server/ MySQL / PHP) and MAMP packages (Mac OS X / Apache_HTTP_Server / MySQL / PHP) are also available.

As of April 2007, over 20 million Internet domains had web services hosted on servers with PHP installed and mod_php was recorded as the most popular Apache HTTP Server module.[39] PHP is used as the server-side programming language on 75% of all web servers.[40] Web content management systems written in PHP include MediaWiki,[41] Joomla, eZ Publish, WordPress,[42] Drupal [43] and Moodle.[44] All websites created using these tools are written in PHP, including the user-facing portion of Wikipedia, Facebook,[45] and Digg.[46]

Security

Vulnerabilities are caused mostly by not following best practice programming rules: technical security flaws of the language itself or of its core libraries are not frequent (23 in 2008, about 1% of the total).[47][48] Recognizing that programmers cannot be trusted, some languages include taint checking to detect automatically the lack of input validation which induces many issues. Such a feature is being developed for PHP,[49] but its inclusion in a release has been rejected several times in the past.[50][51]

Hosting PHP applications on a server requires careful and constant attention to deal with these security risks.[52] There are advanced protection patches such as Suhosin and Hardening-Patch, especially designed for web hosting environments.[53]

PHPIDS adds security to any PHP application to defend against intrusions. PHPIDS detects Cross-site scripting (XSS), SQL injection, header injection, Directory traversal, Remote File Execution, Local File Inclusion, Denial of Service (DoS).[54]

Syntax

<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8" />
    <title>PHP Test</title>
  </head>
  <body>
  <?php
  echo 'Hello World';
  /* echo("Hello World"); works as well,
  although echo is not a function, but a
  language construct. In some cases, such
  as when multiple parameters are passed
  to echo, parameters cannot be enclosed
  in parentheses. */
  ?>
  </body>
</html>

Hello world program in PHP code embedded within HTML code

The PHP interpreter only executes PHP code within its delimiters. Anything outside its delimiters is not processed by PHP (although non-PHP text is still subject to control structures described within PHP code). The most common delimiters are <?php to open and ?> to close PHP sections. <script language="php"> and </script> delimiters are also available, as are the shortened forms <? or <?= (which is used to echo back a string or variable) and ?> as well as ASP-style short forms <% or <%= and %>. While short delimiters are used, they make script files less portable as support for them can be disabled in the PHP configuration, and so they are discouraged.[55] The purpose of all these delimiters is to separate PHP code from non-PHP code, including HTML.[56]

The first form of delimiters, <?php and ?>, in XHTML and other XML documents, creates correctly formed XML 'processing instructions'.[57] This means that the resulting mixture of PHP code and other markup in the server-side file is itself well-formed XML.

Variables are prefixed with a dollar symbol, and a type does not need to be specified in advance. Unlike function and class names, variable names are case sensitive. Both double-quoted ("") and heredoc strings provide the ability to interpolate a variable's value into the string.[58] PHP treats newlines as whitespace in the manner of a free-form language (except when inside string quotes), and statements are terminated by a semicolon.[59] PHP has three types of comment syntax: /* */ marks block and inline comments; // as well as # are used for one-line comments.[60] The echo statement is one of several facilities PHP provides to output text (e.g. to a web browser).

In terms of keywords and language syntax, PHP is similar to most high level languages that follow the C style syntax. if conditions, for and while loops, and function returns are similar in syntax to languages such as C, C++, Java and Perl.

Data types

PHP stores whole numbers in a platform-dependent range, either a 64-bit or 32-bit signed integer equivalent to the C-language long type. Unsigned integers are converted to signed values in certain situations; this behavior is different from other programming languages.[61] Integer variables can be assigned using decimal (positive and negative), octal, and hexadecimal notations. Floating point numbers are also stored in a platform-specific range. They can be specified using floating point notation, or two forms of scientific notation.[62] PHP has a native Boolean type that is similar to the native Boolean types in Java and C++. Using the Boolean type conversion rules, non-zero values are interpreted as true and zero as false, as in Perl and C++.[62] The null data type represents a variable that has no value. The only value in the null data type is NULL.[62] Variables of the "resource" type represent references to resources from external sources. These are typically created by functions from a particular extension, and can only be processed by functions from the same extension; examples include file, image, and database resources.[62] Arrays can contain elements of any type that PHP can handle, including resources, objects, and even other arrays. Order is preserved in lists of values and in hashes with both keys and values, and the two can be intermingled.[62] PHP also supports strings, which can be used with single quotes, double quotes, nowdoc or heredoc syntax.[63]

The Standard PHP Library (SPL) attempts to solve standard problems and implements efficient data access interfaces and classes.[64]

Functions

PHP has hundreds of base functions and thousands more via extensions. These functions are well documented on the PHP site; however, the built-in library has a wide variety of naming conventions and inconsistencies.[65] PHP currently has no functions for thread programming, although it does support multiprocess programming on POSIX systems.[66]
Additional functions can be defined by a developer:

function myFunction() { //declares a function, this is named myFunction
    return 'John Doe'; //returns the value 'John Doe'
}
 
echo 'My name is ' . myFunction() . '!'; //outputs the text and the return variable of the myFunction, the function is also called
//the result of the output will be 'My name is John Doe!'

PHP 5.2 and earlier

Functions are not first-class functions and can only be referenced by their name, directly or dynamically by a variable containing the name of the function.[67] User-defined functions can be created at any time without being prototyped.[67] Functions can be defined inside code blocks, permitting a run-time decision as to whether or not a function should be defined. Function calls must use parentheses, with the exception of zero argument class constructor functions called with the PHP new operator, where parentheses are optional. PHP supports quasi-anonymous functions through the create_function() function, although they are not true anonymous functions because anonymous functions are nameless, but functions can only be referenced by name, or indirectly through a variable $function_name();, in PHP.[67]

PHP 5.3 and newer

PHP gained support for closures. True anonymous functions are supported using the following syntax:

function getAdder($x) {
    return function($y) use ($x) {
        return $x + $y;
    };
}
 
$adder = getAdder(8);
echo $adder(2); // prints "10"

Here, the getAdder() function creates a closure using the parameter $x (the keyword use imports a variable from the lexical context), which takes an additional argument $y and returns it to the caller. Such a function is a first class object, meaning that it can be stored in a variable, passed as a parameter to other functions, etc. For more details see Lambda functions and closures RFC.

The goto flow control statement is used as follows:

function lock() {
    $file = fopen('file.txt', 'r+');
    retry:
    if (!flock($file, LOCK_EX & LOCK_NB)) {
        goto retry;
    }
    fwrite($file, 'Success!');
    fclose($file);
    return 0;
}

When flock() is called, PHP opens a file and tries to lock it. The target label retry: defines the point to which execution should return if flock() is unsuccessful and goto retry; is called. The goto statement is restricted and requires that the target label be in the same file and context.

The goto statement has been supported since PHP 5.3.

Objects

Basic object-oriented programming functionality was added in PHP 3 and improved in PHP 4.[6] Object handling was completely rewritten for PHP 5, expanding the feature set and enhancing performance.[68] In previous versions of PHP, objects were handled like value types.[68] The drawback of this method was that the whole object was copied when a variable was assigned or passed as a parameter to a method. In the new approach, objects are referenced by handle, and not by value. PHP 5 introduced private and protected member variables and methods, along with abstract classes and final classes as well as abstract methods and final methods. It also introduced a standard way of declaring constructors and destructors, similar to that of other object-oriented languages such as C++, and a standard exception handling model. Furthermore, PHP 5 added interfaces and allowed for multiple interfaces to be implemented. There are special interfaces that allow objects to interact with the runtime system. Objects implementing ArrayAccess can be used with array syntax and objects implementing Iterator or IteratorAggregate can be used with the foreach language construct. There is no virtual table feature in the engine, so static variables are bound with a name instead of a reference at compile time.[69]

If the developer creates a copy of an object using the reserved word clone, the Zend engine will check if a __clone() method has been defined or not. If not, it will call a default __clone() which will copy the object's properties. If a __clone() method is defined, then it will be responsible for setting the necessary properties in the created object. For convenience, the engine will supply a function that imports the properties of the source object, so that the programmer can start with a by-value replica of the source object and only override properties that need to be changed.[70]

Basic example of object-oriented programming as described above:

class Person {
   public $firstName;
   public $lastName;
 
   public function __construct($firstName, $lastName = '') { //Optional parameter
       $this->firstName = $firstName;
       $this->lastName = $lastName;
   }
 
   public function greet() {
       return "Hello, my name is " . $this->firstName . " " . $this->lastName . ".";
   }
 
   static public function staticGreet($firstName, $lastName) {
       return "Hello, my name is " . $firstName . " " . $lastName . ".";
   }
}
 
$he = new Person('John', 'Smith');
$she = new Person('Sally', 'Davis');
$other = new Person('Joe');
 
echo $he->greet(); // prints "Hello, my name is John Smith."
echo '<br />';
echo $she->greet(); // prints "Hello, my name is Sally Davis."
echo '<br />';
echo $other->greet(); // prints "Hello, my name is Joe ."
echo '<br />';
echo Person::staticGreet('Jane', 'Doe'); // prints "Hello, my name is Jane Doe."

Visibility of properties and methods

The visibility of PHP properties and methods refers to visibility in PHP. It is defined using the keywords public, private, and protected. The default is public, if only var is used; var is a synonym for public. Items declared public can be accessed everywhere. protected limits access to inherited classes (and to the class that defines the item). private limits visibility only to the class that defines the item.[71] Objects of the same type have access to each other's private and protected members even though they are not the same instance. PHP's member visibility features have sometimes been described as "highly useful."[72] However, they have also sometimes been described as "at best irrelevant and at worst positively harmful."[73]

Speed optimization

PHP source code is compiled on-the-fly to an internal format that can be executed by the PHP engine.[74][75] In order to speed up execution time and not have to compile the PHP source code every time the webpage is accessed, PHP scripts can also be deployed in executable format using a PHP compiler.

Code optimizers aim to enhance the performance of the compiled code by reducing its size, merging redundant instructions and making other changes that can reduce the execution time. With PHP, there are often opportunities for code optimization.[76] An example of a code optimizer is the eAccelerator PHP extension.[77]

Another approach for reducing compilation overhead for PHP servers is using an opcode cache. Opcode caches work by caching the compiled form of a PHP script (opcodes) in shared memory to avoid the overhead of parsing and compiling the code every time the script runs. An opcode cache, APC, will be built into an upcoming release of PHP.[78]

Opcode caching and code optimization can be combined for best efficiency, as the modifications do not depend on each other (they happen in distinct stages of the compilation).

Compilers

The PHP language was originally implemented as an interpreter. Several compilers have been developed which decouple the PHP language from the interpreter. Advantages of compilation include better execution speed, static analysis, and improved interoperability with code written in other languages.[79] PHP compilers of note include Phalanger, which compiles PHP into CIL byte-code, and HipHop, developed at Facebook and now available as open source, which transforms the PHP Script into C++, then compiles it, reducing server load up to 50%.

Resources

PHP includes free and open source libraries with the core build. PHP is a fundamentally Internet-aware system with modules built in for accessing FTP servers, many database servers, embedded SQL libraries such as embedded PostgreSQL, MySQL and SQLite, LDAP servers, and others. Many functions familiar to C programmers such as those in the stdio family are available in the standard PHP build.[80]

PHP allows developers to write extensions in C to add functionality to the PHP language. These can then be compiled into PHP or loaded dynamically at runtime. Extensions have been written to add support for the Windows API, process management on Unix-like operating systems, multibyte strings (Unicode), cURL, and several popular compression formats. Some more unusual features include integration with Internet Relay Chat, dynamic generation of images and Adobe Flash content, and even speech synthesis. The PHP Extension Community Library (PECL) project is a repository for extensions to the PHP language.[81]

Zend provides a certification exam for programmers to become certified PHP developers.

See also

Notes

  1. ^ a b Rasmus Lerdorf began assembling C code originally written for CGI scripts into a library and accessing the library's functions, including SQL queries, through HTML-embedded commands in 1994; Lerdorf, Rasmus (2007-04-26). "PHP on Hormones - history of PHP presentation by Rasmus Lerdorf given at the MySQL Conference in Santa Clara, California" (mp3). The Conversations Network. http://itc.conversationsnetwork.org/shows/detail3298.html#. Retrieved 2009-12-11. "Every day I would change the language drastically, and it didn't take very long, so by 1995, mid-1995 or so, PHP looked like this. This isn't that far from what PHP looks like today, actually." 
  2. ^ "Introduction: What can PHP do?". PHP Manual. http://www.php.net/manual/en/intro-whatcando.php. Retrieved 2009-03-05. 
  3. ^ a b "Embedding PHP in HTML". O'Reilly. 2001-05-03. http://www.onlamp.com/pub/a/php/2001/05/03/php_foundations.html. Retrieved 2008-02-25. 
  4. ^ "PHP Tutorial". http://www.w3schools.com/php/default.asp. Retrieved 2011-05-28. 
  5. ^ "Usage Stats for April 2007". http://www.php.net/usage.php. Retrieved 2008-07-07. 
  6. ^ a b c d e f g h "History of PHP and related projects". The PHP Group. http://www.php.net/history. Retrieved 2008-02-25. 
  7. ^ "GPL-Incompatible, Free Software Licenses". Various Licenses and Comments about Them. Free Software Foundation. http://www.fsf.org/licensing/licenses/index_html#GPLIncompatibleLicenses. Retrieved 2008-02-22. 
  8. ^ PHP.net General FAQ
  9. ^ Lerdorf, Rasmus (2007-04-26). "PHP on Hormones" (mp3). The Conversations Network. http://itc.conversationsnetwork.org/shows/detail3298.html. Retrieved 2009-06-22. 
  10. ^ Lerdorf, Rasmus (2007). "Slide 3". slides for 'PHP on Hormones' talk. The PHP Group. http://talks.php.net/show/mysql07key/3. Retrieved 2009-06-22. 
  11. ^ Lerdorf, Rasmus (June 8, 1995). "Announce: Personal Home Page Tools (PHP Tools)". http://groups.google.com/group/comp.infosystems.www.authoring.cgi/msg/cc7d43454d64d133?pli=1. Retrieved 7 June 2011. 
  12. ^ "Zend Engine version 2.0: Feature Overview and Design". Zend Technologies Ltd.. http://www.zend.com/zend/zend-engine-summary.php. Retrieved 2006-09-17. [dead link]
  13. ^ "Late Static Binding in PHP". Digital Sandwich. 2006-02-23. http://www.digitalsandwich.com/archives/53-Late-Static-Binding-in-PHP.html. Retrieved 2008-03-25. 
  14. ^ "Static Keyword". The PHP Group. http://www.php.net/language.oop5.static. Retrieved 2008-03-25. 
  15. ^ "PHP 6". The PHP project. http://news.php.net/php.internals/47120. Retrieved 2010-03-27. 
  16. ^ "Using Register Globals". PHP. http://www.php.net/register_globals. Retrieved 2008-04-04. 
  17. ^ "php.net 2007 news archive". The PHP Group. 2007-07-13. http://www.php.net/archive/2007.php. Retrieved 2008-02-22. 
  18. ^ "Prepare for PHP 6". CorePHP. 2005-11-23. http://www.corephp.co.uk/archives/19-Prepare-for-PHP-6.html. Retrieved 2008-03-24. 
  19. ^ "PHP 5.3 migration guide". The PHP project. http://www.php.net/migration53. Retrieved 2009-07-03. 
  20. ^ "GoPHP5". http://www.gophp5.org/projects. 
  21. ^ GoPHP5. "PHP projects join forces to Go PHP 5" (PDF). GoPHP5 Press Release. http://gophp5.org/sites/gophp5.org/files/press_release.pdf. Retrieved 2008-02-23. 
  22. ^ "GoPHP5". GoPHP5. http://gophp5.org/. Retrieved 2008-02-22. 
  23. ^ "Unicode". The PHP Group. http://www.php.net/~derick/meeting-notes.html#unicode. Retrieved 2008-03-25. 
  24. ^ Byfield, Bruce (February 28, 2007). "Upcoming PHP release will offer Unicode support". linux.com. http://www.linux.com/archive/feature/60386. Retrieved 2009-06-23. 
  25. ^ The PHP Group. "PHP For Windows snapshots". PHP Windows Development Team. http://windows.php.net/snapshots/. Retrieved 2009-05-25. 
  26. ^ "The PHP License, version 3.01". http://www.php.net/license/3_01.txt. Retrieved 2010-05-20. 
  27. ^ "GPL-Incompatible, Free Software Licenses". Various Licenses and Comments about Them. Free Software Foundation. http://www.gnu.org/licenses/license-list.html#GPLIncompatibleLicenses. Retrieved 2011-01-03. 
  28. ^ a b c d e "PHP: PHP 4 ChangeLog". The PHP Group. 2008-01-03. http://www.php.net/ChangeLog-4.php. Retrieved 2008-02-22. 
  29. ^ "PHP: Using PHP from the command line - Manual:". The PHP Group. http://us3.php.net/manual/en/features.commandline.php. Retrieved 2009-09-11. 
  30. ^ "Downloads". PHP. http://www.php.net/downloads.php#v4. Retrieved 2009-07-29. 
  31. ^ "4.4.9 Release Announcement". PHP. http://www.php.net/releases/4_4_9.php. Retrieved 2009-07-29. 
  32. ^ a b c "PHP: PHP 5 ChangeLog". The PHP Group. 2007-11-08. http://www.php.net/ChangeLog-5.php. Retrieved 2008-02-22. 
  33. ^ "PHP: Release Process". 2011-07-23. https://wiki.php.net/rfc/releaseprocess. Retrieved 2008-02-22. 
  34. ^ "PHP Manual Image Processing and GD;". php.net. http://php.net/manual/en/book.image.php. Retrieved 2011-04-09. 
  35. ^ Archived June 11, 2008 at the Wayback Machine[not in citation given]
  36. ^ "PHP and MySQL". University of Alabama. Archived from the original on 2008-02-28. http://web.archive.org/web/20080228003031/http://cs.ua.edu/457/Notes/PHP+and+MySQL.ppt. Retrieved 2008-02-25. 
  37. ^ "PHP Server-Side Scripting Language". Indiana University. 2007-04-04. http://webmaster.iu.edu/PHPlanguage/index.shtml. Retrieved 2008-02-25. 
  38. ^ "JavaServer Pages Technology — JavaServer Pages Comparing Methods for Server-Side Dynamic Content White Paper". Sun Microsystems. http://java.sun.com/products/jsp/jspservlet.html. Retrieved 2008-02-25. 
  39. ^ "PHP: PHP Usage Stats". SecuritySpace. 2007-04-01. http://www.php.net/usage.php. Retrieved 2008-02-24. 
  40. ^ "Usage of server-side programming languages for websites". W3Techs. 2010-10-29. http://w3techs.com/technologies/overview/programming_language/all. Retrieved 2010-10-29. 
  41. ^ "Manual:Installation requirements#PHP". MediaWiki. 2010-01-25. http://www.mediawiki.org/w/index.php?title=Manual:Installation_requirements&oldid=299556#PHP. Retrieved 2010-02-26. "PHP is the programming language in which MediaWiki is written [...]" 
  42. ^ "About WordPress". http://wordpress.org/about/. Retrieved 2010-02-26. "WordPress was [...] built on PHP" 
  43. ^ "PHP and Drupal". Drupal.org. http://drupal.org/node/176052. Retrieved 2010-06-13. 
  44. ^ "Moodle - About". Moodle.org. http://docs.moodle.org/en/About_Moodle. Retrieved 2009-12-20. 
  45. ^ "PHP and Facebook | Facebook". Blog.facebook.com. http://blog.facebook.com/blog.php?post=2356432130. Retrieved 2009-07-29. 
  46. ^ "PHP and Digg". O'Reilly. http://www.oreillynet.com/onlamp/blog/2006/04/digg_phps_scalability_and_perf.html. Retrieved 2010-06-13. 
  47. ^ "Security and... Driving? (and Hiring) - Sean Coates: PHP, Web (+Beer)". Sean Coates. http://seancoates.com/security-and-driving-and-hiring. Retrieved 2009-07-29. 
  48. ^ Computerworlduk.com, Interview: Ivo Jansch, February 26, 2008
  49. ^ "PHP Taint Mode RFC". http://wiki.php.net/rfc/taint. 
  50. ^ "Developer Meeting Notes, Nov. 2005". http://www.php.net/~derick/meeting-notes.html#sand-boxing-or-taint-mode. 
  51. ^ "Taint mode decision, November 2007". http://devzone.zend.com/article/2798-Zend-Weekly-Summaries-Issue-368#Heading1. 
  52. ^ "The Power of PHP, both Good and Evil". 2009-02-28. http://www.cwihosting.com/php_security.php. 
  53. ^ "Hardened-PHP Project". 2008-08-15. http://www.hardened-php.net. 
  54. ^ "PHPIDS". 2011-02-20. http://phpids.org. 
  55. ^ "PHP: Basic syntax". The PHP Group. http://www.php.net/manual/en/language.basic-syntax.php. Retrieved 2008-02-22. 
  56. ^ "Your first PHP-enabled page". The PHP Group. http://www.php.net/manual/en/tutorial.firstpage.php. Retrieved 2008-02-25. 
  57. ^ Bray, Tim; et al (26 November 2008). "Processing Instructions". Extensible Markup Language (XML) 1.0 (Fifth Edition). W3C. http://www.w3.org/TR/2008/REC-xml-20081126/#sec-pi. Retrieved 2009-06-18. 
  58. ^ "Variables". The PHP Group. http://www.php.net/manual/en/language.variables.php. Retrieved 2008-03-16. 
  59. ^ "Instruction separation". The PHP Group. http://www.php.net/basic-syntax.instruction-separation. Retrieved 2008-03-16. 
  60. ^ "Comments". The PHP Group. http://www.php.net/manual/en/language.basic-syntax.comments.php. Retrieved 2008-03-16. 
  61. ^ "Integers in PHP, running with scissors, and portability". MySQL Performance Blog. March 27, 2007. http://www.mysqlperformanceblog.com/2007/03/27/integers-in-php-running-with-scissors-and-portability/. Retrieved 2007-03-28. 
  62. ^ a b c d e "Types". The PHP Group. http://www.php.net/manual/en/language.types.php. Retrieved 2008-03-16. 
  63. ^ "Strings". The PHP Group. http://www.php.net/manual/en/language.types.string.php. Retrieved 2008-03-21. 
  64. ^ "SPL — StandardPHPLibrary". PHP.net. March 16, 2009. http://www.php.net/spl. Retrieved 2009-03-16. 
  65. ^ "Problems with PHP". http://toykeeper.net/soapbox/php_problems/. Retrieved 20 December 2010. 
  66. ^ "PHP.NET: Process Control". http://nz.php.net/manual/en/book.pcntl.php. Retrieved 2009-08-06. 
  67. ^ a b c "Functions". The PHP Group. http://www.php.net/manual/en/language.functions.php. Retrieved 2008-03-16. 
  68. ^ a b "PHP 5 Object References". mjtsai. http://mjtsai.com/blog/2004/07/15/php-5-object-references/. Retrieved 2008-03-16. 
  69. ^ "Classes and Objects (PHP 5)". The PHP Group. http://www.php.net/zend-engine-2.php. Retrieved 2008-03-16. 
  70. ^ "Object cloning". The PHP Group. http://www.php.net/language.oop5.cloning. Retrieved 2008-03-16. 
  71. ^ "PHP: Visibility - Manual". Theserverpages.com. 2005-05-19. http://theserverpages.com/php/manual/en/language.oop5.visibility.php. Retrieved 2010-08-26. 
  72. ^ Gervasio, Alejandro. "More on Private Methods with PHP 5 Member Visibility". devshed.com. http://www.devshed.com/c/a/PHP/More-on-Private-Methods-with-PHP-5-Member-Visibility/. Retrieved 24 November 2010. 
  73. ^ "Visibility in PHP: Public, Private and Protected". Aperiplus.sourceforge.net. http://aperiplus.sourceforge.net/visibility.php. Retrieved 2010-08-26. 
  74. ^ "How do computer languages work?". http://www.linux-tutorial.info/modules.php?name=Howto&pagename=Unix-and-Internet-Fundamentals-HOWTO/languages.html. Retrieved 2009-11-04. 
  75. ^ (Gilmore 2006, p. 43)
  76. ^ "PHP Accelerator 1.2 (page 3, Code Optimisation)" (PDF). Nick Lindridge. http://www.php-accelerator.co.uk/PHPA_Article.pdf. Retrieved 2008-03-28. 
  77. ^ "eAccelerator". eaccelerator.net. http://eaccelerator.net/. Retrieved 2009-09-18. 
  78. ^ "Upcoming PHP6 Additions & Changes". http://davidwalsh.name/php6. Retrieved 2009-09-18. 
  79. ^ Favre, Nicolas (2010-02-16). "A review of PHP compilers and their outputs". Technow.owlient.eu. http://technow.owlient.eu/index.php?post/2010/02/20/php-compilers. Retrieved 2010-05-20. 
  80. ^ "PHP Function List". The PHP Group. http://www.php.net/quickref.php. Retrieved 2008-02-25. 
  81. ^ "Developing Custom PHP Extensions". devnewz. 2002-09-09. Archived from the original on 2008-02-18. http://web.archive.org/web/20080218045752/http://www.devnewz.com/090902b.html. Retrieved 2008-02-25. 


External links


Wikimedia Foundation. 2010.

Игры ⚽ Нужен реферат?

Look at other dictionaries:

  • PHP — serverseitig interpretierte Skriptsprache Basisdaten Paradigmen: imperativ, objektorientiert Erscheinungsjahr …   Deutsch Wikipedia

  • PHP/FI — PHP serverseitig interpretierte Skriptsprache Basisdaten Paradigmen: imperativ, objektorientiert Erscheinungsjahr …   Deutsch Wikipedia

  • Php — serverseitig interpretierte Skriptsprache Basisdaten Paradigmen: imperativ, objektorientiert Erscheinungsjahr …   Deutsch Wikipedia

  • Php — PHP: Hypertext Preprocessor « PHP » redirige ici. Pour les autres significations, voir PHP (homonymie) …   Wikipédia en Français

  • PHP — Desarrollador(es) PHP Group php.net/ Información general …   Wikipedia Español

  • PHP —   [Abk. für Hypertext PreProcessor; früher stand PHP für Personal Homepage Tools, dt. »Werkzeuge für persönliche Webseiten«, oder für Professional Homepage], in HTML eingebettete …   Universal-Lexikon

  • PHP-Qt — Тип Библиотека Разработчик Katrina Niolet, Jean Luc Gyger, Thomas Moenicke Операционная система Кроссплатформенный Последняя версия 0.9 (26 декабря 2007) Лицензия GNU Lesser General Public License …   Википедия

  • PHP-Qt — Desarrollador Thomas Moenicke Información general Última versión estable 0.9 26 de diciembre de 2007 …   Wikipedia Español

  • PHP — (acrónimo recursivo de PHP: Hypertext Preprocessor , originado inicialmente del nombre PHP Tools, o Personal Home Page Tools) es un lenguaje de programación interpretado, con licencia open source …   Enciclopedia Universal

  • PHP — (Personal Home Page) cross platform server side scripting language used to create dynamic Web pages (Computers) PHP (Personal Handy Phone) mobile phone handset used in conjunction with the Japanese mobile phone system called Personal Handy Phone… …   English contemporary dictionary

  • PHP — система разработки сценариев, включающая: CGI интерфейс, интерпретатор языка; и набор функций для доступа к базам данных и различным объектам WWW. См. также: Скрипт языки CGI приложения Финансовый словарь Финам …   Финансовый словарь

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”