PHP: Manual Quick Reference

<!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml" lang="en"> <head> <meta charset="utf-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <title>PHP: Manual Quick Reference</title> <link rel="icon" type="image/svg+xml" sizes="any" href="https://www.php.net/favicon.svg?v=2"> <link rel="icon" type="image/png" sizes="196x196" href="https://www.php.net/favicon-196x196.png?v=2"> <link rel="icon" type="image/png" sizes="32x32" href="https://www.php.net/favicon-32x32.png?v=2"> <link rel="icon" type="image/png" sizes="16x16" href="https://www.php.net/favicon-16x16.png?v=2"> <link rel="shortcut icon" href="https://www.php.net/favicon.ico?v=2"> <link rel="search" type="application/opensearchdescription+xml" href="http://php.net/phpnetimprovedsearch.src" title="Add PHP.net search"> <link rel="alternate" type="application/atom+xml" href="https://www.php.net/releases/feed.php" title="PHP Release feed"> <link rel="alternate" type="application/atom+xml" href="https://www.php.net/feed.atom" title="PHP: Hypertext Preprocessor"> <link rel="canonical" href="https://www.php.net/quickref.php"> <link rel="shorturl" href="https://www.php.net/quickref"> <link rel="alternate" href="https://www.php.net/quickref" hreflang="x-default"> <link rel="stylesheet" type="text/css" href="/cached.php?t=1707321815&f=/fonts/Fira/fira.css" media="screen"> <link rel="stylesheet" type="text/css" href="/cached.php?t=1707321815&f=/fonts/Font-Awesome/css/fontello.css" media="screen"> <link rel="stylesheet" type="text/css" href="/cached.php?t=1730558402&f=/styles/theme-base.css" media="screen"> <link rel="stylesheet" type="text/css" href="/cached.php?t=1730558402&f=/styles/theme-medium.css" media="screen"> <base href="https://www.php.net/manual-lookup.php"> <meta name="Description" content="PHP is a popular general-purpose scripting language that powers everything from your blog to the most popular websites in the world." /> <meta name="twitter:card" content="summary_large_image" /> <meta name="twitter:site" content="@official_php" /> <meta name="twitter:title" content="PHP: Hypertext Preprocessor" /> <meta name="twitter:description" content="PHP is a popular general-purpose scripting language that powers everything from your blog to the most popular websites in the world." /> <meta name="twitter:creator" content="@official_php" /> <meta name="twitter:image:src" content="https://www.php.net/images/meta-image.png" /> <meta itemprop="name" content="PHP: Hypertext Preprocessor" /> <meta itemprop="description" content="PHP is a popular general-purpose scripting language that powers everything from your blog to the most popular websites in the world." /> <meta itemprop="image" content="https://www.php.net/images/meta-image.png" /> <meta property="og:image" content="https://www.php.net/images/meta-image.png" /> <meta property="og:description" content="PHP is a popular general-purpose scripting language that powers everything from your blog to the most popular websites in the world." /> <link href="https://fosstodon.org/@php" rel="me" /> </head> <body class="help "> <nav class="navbar navbar-fixed-top"> <div class="navbar__inner"> <a href="/" aria-label="PHP Home" class="navbar__brand"> <img src="/images/logos/php-logo-white.svg" aria-hidden="true" width="80" height="40" > </a> <div id="navbar__offcanvas" tabindex="-1" class="navbar__offcanvas" aria-label="Menu" > <button id="navbar__close-button" class="navbar__icon-item navbar_icon-item--visually-aligned navbar__close-button" > <svg xmlns="http://www.w3.org/2000/svg" width="24" viewBox="0 0 24 24" fill="currentColor"><path d="M19,6.41L17.59,5L12,10.59L6.41,5L5,6.41L10.59,12L5,17.59L6.41,19L12,13.41L17.59,19L19,17.59L13.41,12L19,6.41Z" /></svg> </button> <ul class="navbar__nav"> <li class="navbar__item"> <a href="/downloads.php" class="navbar__link " > Downloads </a> </li> <li class="navbar__item"> <a href="/docs.php" class="navbar__link " > Documentation </a> </li> <li class="navbar__item"> <a href="/get-involved.php" class="navbar__link " > Get Involved </a> </li> <li class="navbar__item"> <a href="/support.php" aria-current="page" class="navbar__link navbar__link--active " > Help </a> </li> <li class="navbar__item"> <a href="/releases/8.4/index.php" class="navbar__link navbar__release" > <img src="/images/php8/logo_php8_4.svg" alt="PHP 8.4"> </a> </li> </ul> </div> <div class="navbar__right">  <form action="/manual-lookup.php" class="navbar__search-form" > <label for="navbar__search-input" aria-label="Search docs"> <svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" width="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" > <circle cx="11" cy="11" r="8"></circle> <line x1="21" y1="21" x2="16.65" y2="16.65"></line> </svg> </label> <input type="search" name="pattern" id="navbar__search-input" class="navbar__search-input" placeholder="Search docs" accesskey="s" > <input type="hidden" name="scope" value="quickref"> </form>  <button id="navbar__search-button" class="navbar__search-button" hidden > <svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" width="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" > <circle cx="11" cy="11" r="8"></circle> <line x1="21" y1="21" x2="16.65" y2="16.65"></line> </svg> Search docs </button>  <a id="navbar__search-link" href="/lookup-form.php" aria-label="Search docs" class="navbar__icon-item navbar__search-link" > <svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" width="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" > <circle cx="11" cy="11" r="8"></circle> <line x1="21" y1="21" x2="16.65" y2="16.65"></line> </svg> </a> <a id="navbar__menu-link" href="/menu.php" aria-label="Menu" class="navbar__icon-item navbar_icon-item--visually-aligned navbar_menu-link" > <svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" width="24" viewBox="0 0 24 24" fill="currentColor" > <path d="M3,6H21V8H3V6M3,11H21V13H3V11M3,16H21V18H3V16Z" /> </svg> </a>  <button id="navbar__search-button-mobile" aria-label="Search docs" class="navbar__icon-item navbar__search-button-mobile" hidden > <svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" width="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" > <circle cx="11" cy="11" r="8"></circle> <line x1="21" y1="21" x2="16.65" y2="16.65"></line> </svg> </button> <button id="navbar__menu-button" aria-label="Menu" class="navbar__icon-item navbar_icon-item--visually-aligned" hidden > <svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" width="24" viewBox="0 0 24 24" fill="currentColor" > <path d="M3,6H21V8H3V6M3,11H21V13H3V11M3,16H21V18H3V16Z" /> </svg> </button> </div> <div id="navbar__backdrop" class="navbar__backdrop" ></div> </div> <div id="flash-message"></div> </nav> <div class="headsup"><a href='/index.php#2024-11-21-4'>PHP 8.4.1 Released!</a></div> <nav id="trick"><div><dl> <dt><a href='/manual/en/getting-started.php'>Getting Started</a></dt> <dd><a href='/manual/en/introduction.php'>Introduction</a></dd> <dd><a href='/manual/en/tutorial.php'>A simple tutorial</a></dd> <dt><a href='/manual/en/langref.php'>Language Reference</a></dt> <dd><a href='/manual/en/language.basic-syntax.php'>Basic syntax</a></dd> <dd><a href='/manual/en/language.types.php'>Types</a></dd> <dd><a href='/manual/en/language.variables.php'>Variables</a></dd> <dd><a href='/manual/en/language.constants.php'>Constants</a></dd> <dd><a href='/manual/en/language.expressions.php'>Expressions</a></dd> <dd><a href='/manual/en/language.operators.php'>Operators</a></dd> <dd><a href='/manual/en/language.control-structures.php'>Control Structures</a></dd> <dd><a href='/manual/en/language.functions.php'>Functions</a></dd> <dd><a href='/manual/en/language.oop5.php'>Classes and Objects</a></dd> <dd><a href='/manual/en/language.namespaces.php'>Namespaces</a></dd> <dd><a href='/manual/en/language.enumerations.php'>Enumerations</a></dd> <dd><a href='/manual/en/language.errors.php'>Errors</a></dd> <dd><a href='/manual/en/language.exceptions.php'>Exceptions</a></dd> <dd><a href='/manual/en/language.fibers.php'>Fibers</a></dd> <dd><a href='/manual/en/language.generators.php'>Generators</a></dd> <dd><a href='/manual/en/language.attributes.php'>Attributes</a></dd> <dd><a href='/manual/en/language.references.php'>References Explained</a></dd> <dd><a href='/manual/en/reserved.variables.php'>Predefined Variables</a></dd> <dd><a href='/manual/en/reserved.exceptions.php'>Predefined Exceptions</a></dd> <dd><a href='/manual/en/reserved.interfaces.php'>Predefined Interfaces and Classes</a></dd> <dd><a href='/manual/en/reserved.attributes.php'>Predefined Attributes</a></dd> <dd><a href='/manual/en/context.php'>Context options and parameters</a></dd> <dd><a href='/manual/en/wrappers.php'>Supported Protocols and Wrappers</a></dd> </dl> <dl> <dt><a href='/manual/en/security.php'>Security</a></dt> <dd><a href='/manual/en/security.intro.php'>Introduction</a></dd> <dd><a href='/manual/en/security.general.php'>General considerations</a></dd> <dd><a href='/manual/en/security.cgi-bin.php'>Installed as CGI binary</a></dd> <dd><a href='/manual/en/security.apache.php'>Installed as an Apache module</a></dd> <dd><a href='/manual/en/security.sessions.php'>Session Security</a></dd> <dd><a href='/manual/en/security.filesystem.php'>Filesystem Security</a></dd> <dd><a href='/manual/en/security.database.php'>Database Security</a></dd> <dd><a href='/manual/en/security.errors.php'>Error Reporting</a></dd> <dd><a href='/manual/en/security.variables.php'>User Submitted Data</a></dd> <dd><a href='/manual/en/security.hiding.php'>Hiding PHP</a></dd> <dd><a href='/manual/en/security.current.php'>Keeping Current</a></dd> <dt><a href='/manual/en/features.php'>Features</a></dt> <dd><a href='/manual/en/features.http-auth.php'>HTTP authentication with PHP</a></dd> <dd><a href='/manual/en/features.cookies.php'>Cookies</a></dd> <dd><a href='/manual/en/features.sessions.php'>Sessions</a></dd> <dd><a href='/manual/en/features.file-upload.php'>Handling file uploads</a></dd> <dd><a href='/manual/en/features.remote-files.php'>Using remote files</a></dd> <dd><a href='/manual/en/features.connection-handling.php'>Connection handling</a></dd> <dd><a href='/manual/en/features.persistent-connections.php'>Persistent Database Connections</a></dd> <dd><a href='/manual/en/features.commandline.php'>Command line usage</a></dd> <dd><a href='/manual/en/features.gc.php'>Garbage Collection</a></dd> <dd><a href='/manual/en/features.dtrace.php'>DTrace Dynamic Tracing</a></dd> </dl> <dl> <dt><a href='/manual/en/funcref.php'>Function Reference</a></dt> <dd><a href='/manual/en/refs.basic.php.php'>Affecting PHP's Behaviour</a></dd> <dd><a href='/manual/en/refs.utilspec.audio.php'>Audio Formats Manipulation</a></dd> <dd><a href='/manual/en/refs.remote.auth.php'>Authentication Services</a></dd> <dd><a href='/manual/en/refs.utilspec.cmdline.php'>Command Line Specific Extensions</a></dd> <dd><a href='/manual/en/refs.compression.php'>Compression and Archive Extensions</a></dd> <dd><a href='/manual/en/refs.crypto.php'>Cryptography Extensions</a></dd> <dd><a href='/manual/en/refs.database.php'>Database Extensions</a></dd> <dd><a href='/manual/en/refs.calendar.php'>Date and Time Related Extensions</a></dd> <dd><a href='/manual/en/refs.fileprocess.file.php'>File System Related Extensions</a></dd> <dd><a href='/manual/en/refs.international.php'>Human Language and Character Encoding Support</a></dd> <dd><a href='/manual/en/refs.utilspec.image.php'>Image Processing and Generation</a></dd> <dd><a href='/manual/en/refs.remote.mail.php'>Mail Related Extensions</a></dd> <dd><a href='/manual/en/refs.math.php'>Mathematical Extensions</a></dd> <dd><a href='/manual/en/refs.utilspec.nontext.php'>Non-Text MIME Output</a></dd> <dd><a href='/manual/en/refs.fileprocess.process.php'>Process Control Extensions</a></dd> <dd><a href='/manual/en/refs.basic.other.php'>Other Basic Extensions</a></dd> <dd><a href='/manual/en/refs.remote.other.php'>Other Services</a></dd> <dd><a href='/manual/en/refs.search.php'>Search Engine Extensions</a></dd> <dd><a href='/manual/en/refs.utilspec.server.php'>Server Specific Extensions</a></dd> <dd><a href='/manual/en/refs.basic.session.php'>Session Extensions</a></dd> <dd><a href='/manual/en/refs.basic.text.php'>Text Processing</a></dd> <dd><a href='/manual/en/refs.basic.vartype.php'>Variable and Type Related Extensions</a></dd> <dd><a href='/manual/en/refs.webservice.php'>Web Services</a></dd> <dd><a href='/manual/en/refs.utilspec.windows.php'>Windows Only Extensions</a></dd> <dd><a href='/manual/en/refs.xml.php'>XML Manipulation</a></dd> <dd><a href='/manual/en/refs.ui.php'>GUI Extensions</a></dd> </dl> <dl> <dt>Keyboard Shortcuts</dt><dt>?</dt> <dd>This help</dd> <dt>j</dt> <dd>Next menu item</dd> <dt>k</dt> <dd>Previous menu item</dd> <dt>g p</dt> <dd>Previous man page</dd> <dt>g n</dt> <dd>Next man page</dd> <dt>G</dt> <dd>Scroll to bottom</dd> <dt>g g</dt> <dd>Scroll to top</dd> <dt>g h</dt> <dd>Goto homepage</dd> <dt>g s</dt> <dd>Goto search<br>(current page)</dd> <dt>/</dt> <dd>Focus search box</dd> </dl></div></nav> <div id="goto"> <div class="search"> <div class="text"></div> <div class="results"><ul></ul></div> </div> </div> <div id="layout" class="clearfix"> <section id="layout-content"> <h1>PHP Function List</h1> <p> <b>/refs.international.php</b> doesn't exist. Closest matches: </p>  <ul id="quickref_functions"> <li><a href="/manual/en/function.imagesetinterpolation.php">imagesetinterpolation</a></li> <li><a href="/manual/en/function.iterator-apply.php">iterator_apply</a></li> <li><a href="/manual/en/class.reflectionintersectiontype.php">reflectionintersectiontype</a></li> <li><a href="/manual/en/class.norewinditerator.php">norewinditerator</a></li> <li><a href="/manual/en/class.recursiveiterator.php">recursiveiterator</a></li> <li><a href="/manual/en/class.regexiterator.php">regexiterator</a></li> <li><a href="/manual/en/function.imagegetinterpolation.php">imagegetinterpolation</a></li> <li><a href="/manual/en/function.register-tick-function.php">register_tick_function</a></li> <li><a href="/manual/en/function.var-representation.php">var_representation</a></li> <li><a href="/manual/en/class.reflectionproperty.php">reflectionproperty</a></li> <li><a href="/manual/en/class.reflectiontype.php">reflectiontype</a></li> <li><a href="/manual/en/class.parentiterator.php">parentiterator</a></li> <li><a href="/manual/en/class.reflection.php">reflection</a></li> <li><a href="/manual/en/function.imageaffinematrixconcat.php">imageaffinematrixconcat</a></li> <li><a href="/manual/en/class.reflectionnamedtype.php">reflectionnamedtype</a></li> <li><a href="/manual/en/function.create-function.php">create_function</a></li> <li><a href="/manual/en/class.reflectionclass.php">reflectionclass</a></li> <li><a href="/manual/en/function.unregister-tick-function.php">unregister_tick_function</a></li> <li><a href="/manual/en/class.recursivecachingiterator.php">recursivecachingiterator</a></li> <li><a href="/manual/en/function.stream-filter-append.php">stream_filter_append</a></li> <li><a href="/manual/en/class.reflectionmethod.php">reflectionmethod</a></li> <li><a href="/manual/en/class.recursiveiteratoriterator.php">recursiveiteratoriterator</a></li> <li><a href="/manual/en/class.intliterator.php">intliterator</a></li> <li><a href="/manual/en/function.filter-input.php">filter_input</a></li> <li><a href="/manual/en/class.dateinterval.php">dateinterval</a></li> <li><a href="/manual/en/function.get-defined-functions.php">get_defined_functions</a></li> <li><a href="/manual/en/class.recursivetreeiterator.php">recursivetreeiterator</a></li> <li><a href="/manual/en/class.iterator.php">iterator</a></li> <li><a href="/manual/en/class.directoryiterator.php">directoryiterator</a></li> <li><a href="/manual/en/function.get-html-translation-table.php">get_html_translation_table</a></li> </ul>  </section> <aside class="tips"> <div class="inner"><p class="panel"><a href="/search.php?show=all&pattern=%2Frefs.international.php">Full website search</a></div> </aside> </div> <footer> <div class="container footer-content"> <div class="row-fluid"> <ul class="footmenu"> <li><a href="/copyright.php">Copyright © 2001-2024 The PHP Group</a></li> <li><a href="/my.php">My PHP.net</a></li> <li><a href="/contact.php">Contact</a></li> <li><a href="/sites.php">Other PHP.net sites</a></li> <li><a href="/privacy.php">Privacy policy</a></li> <li><a href="https://github.com/php/web-php/blob/master/quickref.php">View Source</a></li> </ul> </div> </div> </footer> <script src="/cached.php?t=1731172202&f=/js/ext/jquery-3.6.0.min.js"></script> <script src="/cached.php?t=1723177202&f=/js/ext/FuzzySearch.min.js"></script> <script src="/cached.php?t=1707321815&f=/js/ext/mousetrap.min.js"></script> <script src="/cached.php?t=1707321815&f=/js/ext/jquery.scrollTo.min.js"></script> <script src="/cached.php?t=1730558402&f=/js/search.js"></script> <script src="/cached.php?t=1731172202&f=/js/common.js"></script> <a id="toTop" href="javascript:;"><span id="toTopHover"></span><img width="40" height="40" alt="To Top" src="/images/to-top@2x.png"></a> <div id="search-modal__backdrop" class="search-modal__backdrop"> <div role="dialog" aria-label="Search modal" id="search-modal" class="search-modal" > <div class="search-modal__header"> <div class="search-modal__form"> <div class="search-modal__input-icon">  <svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" width="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" > <circle cx="11" cy="11" r="8"></circle> <line x1="21" y1="21" x2="16.65" y2="16.65"></line> </svg> </div> <input type="search" id="search-modal__input" class="search-modal__input" placeholder="Search docs" aria-label="Search docs" /> </div> <button aria-label="Close" class="search-modal__close">  <svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" width="24" viewBox="0 0 24 24" > <path d="M19,6.41L17.59,5L12,10.59L6.41,5L5,6.41L10.59,12L5,17.59L6.41,19L12,13.41L17.59,19L19,17.59L13.41,12L19,6.41Z"/> </svg> </button> </div> <div role="listbox" aria-label="Search results" id="search-modal__results" class="search-modal__results" ></div> <div class="search-modal__helper-text"> <div> <kbd>↑</kbd> and <kbd>↓</kbd> to navigate • <kbd>Enter</kbd> to select • <kbd>Esc</kbd> to close </div> <div> Press <kbd>Enter</kbd> without selection to search using Google </div> </div> </div> </div> </body> </html>

CINXE.COM

PHP: Manual Quick Reference