hyperreal/wiki.bash-hackers.org
1
0
Fork 0
mirror of https://github.com/rawiriblundell/wiki.bash-hackers.org synced 2024-12-25 22:20:39 +01:00
Code Issues Actions Packages Projects Releases Wiki Activity
80bd32e686
wiki.bash-hackers.org/commands/builtin/declare

468 lines
31 KiB
Plaintext
Raw Normal View History

First crawl of archive.org
2023-04-14 13:44:41 +02:00
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml" lang="en" dir="ltr" class="no-js">
<head><script type="text/javascript" src="/_static/js/bundle-playback.js?v=TPXmWR5s" charset="utf-8"></script>
<script type="text/javascript" src="/_static/js/wombat.js?v=txqj7nKC" charset="utf-8"></script>
<script type="text/javascript">
__wm.init("http://web.archive.org/web");
__wm.wombat("https://wiki.bash-hackers.org/commands/builtin/declare?do=edit","20220706172727","http://web.archive.org/","web","/_static/",
"1657128447");
</script>
<link rel="stylesheet" type="text/css" href="/_static/css/banner-styles.css?v=S1zqJCYt" />
<link rel="stylesheet" type="text/css" href="/_static/css/iconochive.css?v=qtvMKcIJ" />
<!-- End Wayback Rewrite JS Include -->
<meta charset="UTF-8"/>
<title>The declare builtin command [Bash Hackers Wiki]</title>
<script>(function(H){H.className=H.className.replace(/\bno-js\b/,'js')})(document.documentElement)</script>
<meta name="viewport" content="width=device-width,initial-scale=1"/>
<link rel="shortcut icon" href="/web/20220706172727im_/https://wiki.bash-hackers.org/lib/tpl/bootstrap3/images/favicon.ico"/>
<link rel="apple-touch-icon" href="/web/20220706172727im_/https://wiki.bash-hackers.org/lib/tpl/bootstrap3/images/apple-touch-icon.png"/>
<meta name="generator" content="DokuWiki"/>
<meta name="robots" content="noindex,nofollow"/>
<link type="text/css" rel="stylesheet" href="/web/20220706172727cs_/https://wiki.bash-hackers.org/lib/tpl/bootstrap3/assets/bootstrap/default/bootstrap.min.css"/>
<link rel="search" type="application/opensearchdescription+xml" href="/web/20220706172727/https://wiki.bash-hackers.org/lib/exe/opensearch.php" title="Bash Hackers Wiki"/>
<link rel="start" href="/"/>
<link rel="contents" href="/commands/builtin/declare?do=index" title="Sitemap"/>
<link rel="manifest" href="/web/20220706172727/https://wiki.bash-hackers.org/lib/exe/manifest.php"/>
<link rel="alternate" type="application/rss+xml" title="Recent Changes" href="/web/20220706172727/https://wiki.bash-hackers.org/feed.php"/>
<link rel="alternate" type="application/rss+xml" title="Current namespace" href="/web/20220706172727/https://wiki.bash-hackers.org/feed.php?mode=list&amp;ns=commands:builtin"/>
<link rel="alternate" type="text/html" title="Plain HTML" href="/web/20220706172727/https://wiki.bash-hackers.org/_export/xhtml/commands/builtin/declare"/>
<link rel="alternate" type="text/plain" title="Wiki Markup" href="/web/20220706172727/https://wiki.bash-hackers.org/_export/raw/commands/builtin/declare"/>
<link rel="stylesheet" type="text/css" href="/web/20220706172727cs_/https://wiki.bash-hackers.org/lib/exe/css.php?t=bootstrap3&amp;tseed=54923c3deda180f2db5bd755cd8fbf1a"/>
<!--[if gte IE 9]><!-->
<script type="text/javascript">/*<![CDATA[*/var NS='commands:builtin';var JSINFO = {"updatable":1,"userreplace":1,"default_macro_string":"","plugins":{"edittable":{"default columnwidth":""}},"move_renameokay":false,"isadmin":0,"isauth":0,"bootstrap3":{"mode":"source","toc":[],"config":{"collapsibleSections":0,"fixedTopNavbar":1,"showSemanticPopup":0,"sidebarOnNavbar":0,"tagsOnTop":1,"tocAffix":1,"tocCollapseOnScroll":1,"tocCollapsed":0,"tocLayout":"default","useAnchorJS":1,"useAlternativeToolbarIcons":1}},"id":"commands:builtin:declare","namespace":"commands:builtin","ACT":"source","useHeadingNavigation":1,"useHeadingContent":1};
/*!]]>*/</script>
<script type="text/javascript" charset="utf-8" src="/web/20220706172727js_/https://wiki.bash-hackers.org/lib/exe/jquery.php?tseed=23f888679b4f1dc26eef34902aca964f"></script>
<script type="text/javascript" charset="utf-8" src="/web/20220706172727js_/https://wiki.bash-hackers.org/lib/exe/js.php?t=bootstrap3&amp;tseed=54923c3deda180f2db5bd755cd8fbf1a"></script>
<script type="text/javascript">/*<![CDATA[*/if (typeof IconifyConfig == 'undefined') { var IconifyConfig = { 'defaultAPI' : '/lib/tpl/bootstrap3/iconify.php?prefix={prefix}&icons={icons}' } }
/*!]]>*/</script>
<script type="text/javascript" src="/web/20220706172727js_/https://wiki.bash-hackers.org/lib/tpl/bootstrap3/assets/bootstrap/js/bootstrap.min.js"></script>
<script type="text/javascript" src="/web/20220706172727js_/https://wiki.bash-hackers.org/lib/tpl/bootstrap3/assets/anchorjs/anchor.min.js"></script>
<script type="text/javascript" src="/web/20220706172727js_/https://wiki.bash-hackers.org/lib/tpl/bootstrap3/assets/typeahead/bootstrap3-typeahead.min.js"></script>
<script type="text/javascript" src="/web/20220706172727js_/https://wiki.bash-hackers.org/lib/tpl/bootstrap3/assets/iconify/iconify.min.js"></script>
<script type="text/javascript" src="/web/20220706172727js_/https://wiki.bash-hackers.org/lib/tpl/bootstrap3/assets/iconify/plugins/fa.js"></script>
<!--<![endif]-->
<style type="text/css">@media screen { body { margin-top: 65px; } #dw__toc.affix { top: 55px; position: fixed !important; } #dw__toc .nav .nav .nav { display: none; } }</style>
<!--[if lt IE 9]>
<script type="text/javascript" src="https://oss.maxcdn.com/html5shiv/3.7.2/html5shiv.min.js"></script>
<script type="text/javascript" src="https://oss.maxcdn.com/respond/1.4.2/respond.min.js"></script>
<![endif]-->
</head>
<body class="default dokuwiki mode_source tpl_bootstrap3 dw-page-on-panel dw-fluid-container" data-page-id="commands:builtin:declare"><div class="dokuwiki">
<header id="dokuwiki__header" class="dw-container dokuwiki container-fluid mx-5">
<!-- navbar -->
<nav id="dw__navbar" class="navbar navbar-fixed-top navbar-default" role="navigation">
<div class="dw-container container-fluid mx-5">
<div class="navbar-header">
<button class="navbar-toggle" type="button" data-toggle="collapse" data-target=".navbar-collapse">
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</button>
<a class="navbar-brand d-flex align-items-center" href="/web/20220706172727/https://wiki.bash-hackers.org/start" accesskey="h" title="Bash Hackers Wiki"><img id="dw__logo" class="pull-left h-100 mr-4" alt="Bash Hackers Wiki" src="/web/20220706172727im_/https://wiki.bash-hackers.org/lib/tpl/bootstrap3/images/logo.png"/><div class="pull-right"><div id="dw__title">Bash Hackers Wiki</div></div></a>
</div>
<div class="collapse navbar-collapse">
<div class="navbar-right" id="dw__navbar_items">
<!-- navbar-searchform -->
<form action="/web/20220706172727/https://wiki.bash-hackers.org/commands/builtin/declare" accept-charset="utf-8" class="navbar-form navbar-left search" id="dw__search" method="get" role="search">
<div class="input-group">
<input id="qsearch" autocomplete="off" type="search" placeholder="Search" value="" accesskey="f" name="q" class="form-control" title="[F]"/>
<div class="input-group-btn">
<button class="btn btn-default" type="submit" title="Search">
<span class="iconify" data-icon="mdi:magnify"></span> </button>
</div>
</div>
<input type="hidden" name="do" value="search"/>
</form>
<!-- /navbar-searchform -->
<!-- tools-menu -->
<ul class="nav navbar-nav dw-action-icon" id="dw__tools">
<li class="dropdown">
<a href="" class="dropdown-toggle" data-target="#" data-toggle="dropdown" title="" role="button" aria-haspopup="true" aria-expanded="false">
<span class="iconify" data-icon="mdi:wrench"></span> <span class="hidden-lg hidden-md hidden-sm">Tools</span> <span class="caret"></span>
</a>
<ul class="dropdown-menu tools" role="menu">
<li class="dropdown-header">
<span class="iconify" data-icon="mdi:account"></span> User Tools </li>
<li class="action"><a href="/web/20220706172727/https://wiki.bash-hackers.org/commands/builtin/declare?do=register" title="Register" rel="nofollow" class="menuitem register"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewbox="0 0 24 24"><path d="M15 14c-2.67 0-8 1.33-8 4v2h16v-2c0-2.67-5.33-4-8-4m-9-4V7H4v3H1v2h3v3h2v-3h3v-2m6 2a4 4 0 0 0 4-4 4 4 0 0 0-4-4 4 4 0 0 0-4 4 4 4 0 0 0 4 4z"/></svg><span>Register</span></a></li><li class="action"><a href="/web/20220706172727/https://wiki.bash-hackers.org/commands/builtin/declare?do=login&amp;sectok=" title="Log In" rel="nofollow" class="menuitem login"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewbox="0 0 24 24"><path d="M10 17.25V14H3v-4h7V6.75L15.25 12 10 17.25M8 2h9a2 2 0 0 1 2 2v16a2 2 0 0 1-2 2H8a2 2 0 0 1-2-2v-4h2v4h9V4H8v4H6V4a2 2 0 0 1 2-2z"/></svg><span>Log In</span></a></li>
<li class="divider" role="separator"></li>
<li class="dropdown-header">
<span class="iconify" data-icon="mdi:toolbox"></span> Site Tools </li>
<li class="action"><a href="/web/20220706172727/https://wiki.bash-hackers.org/commands/builtin/declare?do=recent" title="Recent Changes [r]" rel="nofollow" accesskey="r" class="menuitem recent"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewbox="0 0 24 24"><path d="M15 13h1.5v2.82l2.44 1.41-.75 1.3L15 16.69V13m4-5H5v11h4.67c-.43-.91-.67-1.93-.67-3a7 7 0 0 1 7-7c1.07 0 2.09.24 3 .67V8M5 21a2 2 0 0 1-2-2V5c0-1.11.89-2 2-2h1V1h2v2h8V1h2v2h1a2 2 0 0 1 2 2v6.1c1.24 1.26 2 2.99 2 4.9a7 7 0 0 1-7 7c-1.91 0-3.64-.76-4.9-2H5m11-9.85A4.85 4.85 0 0 0 11.15 16c0 2.68 2.17 4.85 4.85 4.85A4.85 4.85 0 0 0 20.85 16c0-2.68-2.17-4.85-4.85-4.85z"/></svg><span>Recent Changes</span></a></li><li class="action"><a href="/web/20220706172727/https://wiki.bash-hackers.org/commands/builtin/declare?do=media&amp;ns=commands%3Abuiltin" title="Media Manager" rel="nofollow" class="menuitem media"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewbox="0 0 24 24"><path d="M7 15l4.5-6 3.5 4.5 2.5-3L21 15m1-11h-8l-2-2H6a2 2 0 0 0-2 2v12a2 2 0 0 0 2 2h16a2 2 0 0 0 2-2V6a2 2 0 0 0-2-2M2 6H0v14a2 2 0 0 0 2 2h18v-2H2V6z"/></svg><span>Media Manager</span></a></li><li class="action"><a href="/web/20220706172727/https://wiki.bash-hackers.org/commands/builtin/declare?do=index" title="Sitemap [x]" rel="nofollow" accesskey="x" class="menuitem index"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewbox="0 0 24 24"><path d="M3 3h6v4H3V3m12 7h6v4h-6v-4m0 7h6v4h-6v-4m-2-4H7v5h6v2H5V9h2v2h6v2z"/></svg><span>Sitemap</span></a></li>
<li class="divider" role="separator"></li>
<li class="dropdown-header">
<span class="iconify" data-icon="mdi:file-document-outline"></span> Page Tools </li>
<li class="action"><a href="/web/20220706172727/https://wiki.bash-hackers.org/commands/builtin/declare?do=" title="Show page [v]" rel="nofollow" accesskey="v" class="menuitem show"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewbox="0 0 24 24"><path d="M13 9h5.5L13 3.5V9M6 2h8l6 6v12a2 2 0 0 1-2 2H6a2 2 0 0 1-2-2V4c0-1.11.89-2 2-2m9 16v-2H6v2h9m3-4v-2H6v2h12z"/></svg><span>Show page</span></a></li><li class="action"><a href="/web/20220706172727/https://wiki.bash-hackers.org/commands/builtin/declare?do=revisions" title="Old revisions [o]" rel="nofollow" accesskey="o" class="menuitem revs"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewbox="0 0 24 24"><path d="M11 7v5.11l4.71 2.79.79-1.28-4-2.37V7m0-5C8.97 2 5.91 3.92 4.27 6.77L2 4.5V11h6.5L5.75 8.25C6.96 5.73 9.5 4 12.5 4a7.5 7.5 0 0 1 7.5 7.5 7.5 7.5 0 0 1-7.5 7.5c-3.27 0-6.03-2.09-7.06-5h-2.1c1.1 4.03 4.77 7 9.16 7 5.24 0 9.5-4.25 9.5-9.5A9.5 9.5 0 0 0 12.5 2z"/></svg><span>Old revisions</span></a></li><li class="action"><a href="/web/20220706172727/https://wiki.bash-hackers.org/commands/builtin/declare?do=backlink" title="Backlinks" rel="nofollow" class="menuitem backlink"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewbox="0 0 24 24"><path d="M10.59 13.41c.41.39.41 1.03 0 1.42-.39.39-1.03.39-1.42 0a5.003 5.003 0 0 1 0-7.07l3.54-3.54a5.003 5.003 0 0 1 7.07 0 5.003 5.003 0 0 1 0 7.07l-1.49 1.49c.01-.82-.12-1.64-.4-2.42l.47-.48a2.982 2.982 0 0 0 0-4.24 2.982 2.982 0 0 0-4.24 0l-3.53 3.53a2.982 2.982 0 0 0 0 4.24m2.82-4.24c.39-.39 1.03-.39 1.42 0a5.003 5.003 0 0 1 0 7.07l-3.54 3.54a5.003 5.003 0 0 1-7.07 0 5.003 5.003 0 0 1 0-7.07l1.49-1.49c-.01.82.12 1.64.4 2.43l-.47.47a2.982 2.982 0 0 0 0 4.24 2.982 2.982 0 0 0 4.24 0l3.53-3.53a2.982 2.982 0 0 0 0-4.24.973.973 0 0 1 0-1.42z"/></svg><span>Backlinks</span></a></li><li class="action"><a href="#dokuwiki__top" title="Back to top [t]" rel="nofollow" accesskey="t" class="menuitem top"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewbox="0 0 24 24"><path d="M13 20h-2V8l-5.5 5.5-1.42-1.42L12 4.16l7.92 7.92-1.42 1.42L13 8v12z"/></svg><span>Back to top</span></a></li>
</ul>
</li>
</ul>
<!-- /tools-menu -->
<ul class="nav navbar-nav">
<li>
<span class="dw__actions dw-action-icon">
<a href="/web/20220706172727/https://wiki.bash-hackers.org/commands/builtin/declare?do=register" title="Register" rel="nofollow" class="menuitem register btn btn-success navbar-btn"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewbox="0 0 24 24"><path d="M15 14c-2.67 0-8 1.33-8 4v2h16v-2c0-2.67-5.33-4-8-4m-9-4V7H4v3H1v2h3v3h2v-3h3v-2m6 2a4 4 0 0 0 4-4 4 4 0 0 0-4-4 4 4 0 0 0-4 4 4 4 0 0 0 4 4z"/></svg><span class=""> Register</span></a><a href="/web/20220706172727/https://wiki.bash-hackers.org/commands/builtin/declare?do=login&amp;sectok=" title="Log In" rel="nofollow" class="menuitem login btn btn-default navbar-btn"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewbox="0 0 24 24"><path d="M10 17.25V14H3v-4h7V6.75L15.25 12 10 17.25M8 2h9a2 2 0 0 1 2 2v16a2 2 0 0 1-2 2H8a2 2 0 0 1-2-2v-4h2v4h9V4H8v4H6V4a2 2 0 0 1 2-2z"/></svg><span class=""> Log In</span></a> </span>
</li>
</ul>
</div>
</div>
</div>
</nav>
<!-- navbar -->
<div align="center">
<script async src="//web.archive.org/web/20220706172727js_/https://pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script>
<!-- BHORG_BOTTOM -->
<ins class="adsbygoogle" style="display:inline-block;width:728px;height:90px" data-ad-client="ca-pub-4658830517838678" data-ad-slot="1603598940"></ins>
<script>
(adsbygoogle = window.adsbygoogle || []).push({});
</script>
</div>
</header>
<a name="dokuwiki__top" id="dokuwiki__top"></a>
<main role="main" class="dw-container pb-5 dokuwiki container-fluid mx-5">
<div id="dokuwiki__pageheader">
<!-- breadcrumbs -->
<nav id="dw__breadcrumbs" class="small">
<hr/>
<div class="dw__youarehere">
<ol class="breadcrumb" itemscope itemtype="http://schema.org/BreadcrumbList"><li>You are here</li><li itemprop="itemListElement" itemscope itemtype="http://schema.org/ListItem"><a href="/web/20220706172727/https://wiki.bash-hackers.org/start" itemprop="item" title="start"><span itemprop="name"><span class="iconify" data-icon="mdi:home"></span></span></a></li><li itemprop="itemListElement" itemscope itemtype="http://schema.org/ListItem"><a itemprop="item" href="/web/20220706172727/https://wiki.bash-hackers.org/commands/start" class="wikilink1" title="commands:start">Commands</a></li><li itemprop="itemListElement" itemscope itemtype="http://schema.org/ListItem"><a itemprop="item" href="/web/20220706172727/https://wiki.bash-hackers.org/commands/builtin/start" class="wikilink1" title="commands:builtin:start">Builtin Commands</a></li><li class="active" itemprop="itemListElement" itemscope itemtype="http://schema.org/ListItem"><span itemprop="name"><a itemprop="item" href="/web/20220706172727/https://wiki.bash-hackers.org/commands/builtin/declare" class="wikilink1" title="commands:builtin:declare">The declare builtin command</a></span></li></ol> </div>
<div class="dw__breadcrumbs hidden-print">
<ol class="breadcrumb"><li>Trace</li> </div>
<hr/>
</nav>
<!-- /breadcrumbs -->
<p class="text-right">
<span class="pageId ml-1 label label-primary">commands:builtin:declare</span> </p>
<div id="dw__msgarea" class="small">
</div>
</div>
<div class="row">
<article id="dokuwiki__content" class="col-sm-12 col-md-12 " itemscope itemtype="http://schema.org/Article" itemref="dw__license">
<!-- page-tools -->
<nav id="dw__pagetools" class="hidden-print">
<div class="tools panel panel-default">
<ul class="nav nav-stacked nav-pills text-muted">
<li class="action"><a href="/web/20220706172727/https://wiki.bash-hackers.org/commands/builtin/declare?do=" title="Show page [v]" rel="nofollow" accesskey="v" class="menuitem show"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewbox="0 0 24 24"><path d="M13 9h5.5L13 3.5V9M6 2h8l6 6v12a2 2 0 0 1-2 2H6a2 2 0 0 1-2-2V4c0-1.11.89-2 2-2m9 16v-2H6v2h9m3-4v-2H6v2h12z"/></svg><span>Show page</span></a></li><li class="action"><a href="/web/20220706172727/https://wiki.bash-hackers.org/commands/builtin/declare?do=revisions" title="Old revisions [o]" rel="nofollow" accesskey="o" class="menuitem revs"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewbox="0 0 24 24"><path d="M11 7v5.11l4.71 2.79.79-1.28-4-2.37V7m0-5C8.97 2 5.91 3.92 4.27 6.77L2 4.5V11h6.5L5.75 8.25C6.96 5.73 9.5 4 12.5 4a7.5 7.5 0 0 1 7.5 7.5 7.5 7.5 0 0 1-7.5 7.5c-3.27 0-6.03-2.09-7.06-5h-2.1c1.1 4.03 4.77 7 9.16 7 5.24 0 9.5-4.25 9.5-9.5A9.5 9.5 0 0 0 12.5 2z"/></svg><span>Old revisions</span></a></li><li class="action"><a href="/web/20220706172727/https://wiki.bash-hackers.org/commands/builtin/declare?do=backlink" title="Backlinks" rel="nofollow" class="menuitem backlink"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewbox="0 0 24 24"><path d="M10.59 13.41c.41.39.41 1.03 0 1.42-.39.39-1.03.39-1.42 0a5.003 5.003 0 0 1 0-7.07l3.54-3.54a5.003 5.003 0 0 1 7.07 0 5.003 5.003 0 0 1 0 7.07l-1.49 1.49c.01-.82-.12-1.64-.4-2.42l.47-.48a2.982 2.982 0 0 0 0-4.24 2.982 2.982 0 0 0-4.24 0l-3.53 3.53a2.982 2.982 0 0 0 0 4.24m2.82-4.24c.39-.39 1.03-.39 1.42 0a5.003 5.003 0 0 1 0 7.07l-3.54 3.54a5.003 5.003 0 0 1-7.07 0 5.003 5.003 0 0 1 0-7.07l1.49-1.49c-.01.82.12 1.64.4 2.43l-.47.47a2.982 2.982 0 0 0 0 4.24 2.982 2.982 0 0 0 4.24 0l3.53-3.53a2.982 2.982 0 0 0 0-4.24.973.973 0 0 1 0-1.42z"/></svg><span>Backlinks</span></a></li><li class="action"><a href="#dokuwiki__top" title="Back to top [t]" rel="nofollow" accesskey="t" class="menuitem top"><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewbox="0 0 24 24"><path d="M13 20h-2V8l-5.5 5.5-1.42-1.42L12 4.16l7.92 7.92-1.42 1.42L13 8v12z"/></svg><span>Back to top</span></a></li> </ul>
</div>
</nav>
<!-- /page-tools -->
<div class="panel panel-default px-3 py-2" itemprop="articleBody">
<div class="page panel-body">
<div class="dw-content-page "><!-- content --><div class="dw-content"><p>
This page is read only. You can view the source, but not change it. Ask your administrator if you think this is wrong.
</p>
<div class="editBox" role="application">
<div class="toolbar group">
<div id="draft__status" class="draft__status"></div>
<div id="tool__bar" class="tool__bar"></div>
</div>
<form id="dw__editform" method="post" action="" accept-charset="utf-8" class=" form-inline"><div class="no">
<input type="hidden" name="sectok" value=""/><input type="hidden" name="id" value="commands:builtin:declare"/><input type="hidden" name="rev" value="0"/><input type="hidden" name="date" value="0"/><input type="hidden" name="prefix" value="."/><input type="hidden" name="suffix" value=""/><input type="hidden" name="changecheck" value="1a4af88046af6438d9b0083afb342093"/><input type="hidden" name="target" value="section"/><textarea name="wikitext" id="wiki__text" dir="auto" class="edit form-control" cols="80" rows="10" tabindex="1" readonly="readonly">
====== The declare builtin command ======
===== Synopsis =====
&lt;code&gt;
declare [-aAfFgilrtux] [-p] [NAME[=VALUE] ...]
# obsolete typeset synonym
typeset [-aAfFgilrtux] [-p] [NAME[=VALUE] ...]
&lt;/code&gt;
===== Description =====
''declare'' is used to display or set variables along with variable attributes. When used to display variables/functions and their value, the output is re-usable as input for the shell.
If no ''NAME'' is given, it displays the values of all variables or functions when restricted by the ''-f'' option.
If ''NAME'' is followed by ''=VALUE'', ''declare'' also sets the value for a variable.
When used in a function, ''declare'' makes ''NAMEs'' local variables, unless used with the ''-g'' option.
Don't use it's synonym ''typeset'' when coding for Bash, since it's tagged as obsolete.
==== Options ====
Below, ''[-+]X'' indicates an attribute, use ''-X'' to set the attribute, ''+X'' to remove it.
^Option ^Description ^
|''[-+]a'' |make NAMEs indexed arrays (removing with ''+a'' is valid syntax, but leads to an error message) |
|''[-+]A'' |make NAMEs associative arrays |
|''[-+]c'' | **Undocumented** convert NAMEs to &quot;capcase&quot; on assignment (makes the first letter upper-case and the rest lower). Requires Bash built with ''-DCASEMOD_CAPCASE'' |
|''-f'' |restrict action or display to function names and definitions (removing with ''+f'' is valid syntax, but leads to an error message) |
|''-F'' |restrict display to function names only (plus line number and source file when debugging) |
|''-g'' |create global variables when used in a shell function; otherwise ignored (by default, ''declare'' declares local scope variables when used in shell functions) |
|''[-+]i'' |make NAMEs have the &quot;integer&quot; attribute |
|''[-+]l'' |convert NAMEs to lower case on assignment (makes sure the variable contains only lower case letters) |
|''[-+]n'' |make NAME a reference to the variable named by its value. Introduced in Bash 4.3-alpha |
|''-p'' |display the attributes and value of each NAME |
|''[-+]r'' |make NAMEs readonly (removing with ''+r'' is valid syntax, but not possible) |
|''[-+]t'' |make NAMEs have the &quot;trace&quot; attribute (effective only for functions) |
|''[-+]u'' |convert NAMEs to upper case on assignment (makes sure the variable contains only upper case letters) |
|''[-+]x'' |make NAMEs exported |
==== Return status ====
^Status ^Reason ^
|0 |no error |
|!= 0 |invalid option |
|!= 0 |invalid variable name given |
|!= 0 |attempt to **define** a function using ''-f'' |
|!= 0 |assignment to a readonly variable |
|!= 0 |removing the readonly-attribute from a readonly variable |
|!= 0 |assignment to an array variable without the compound assignment syntax (''array=(...)'') |
|!= 0 |attempt to use ''+a'' to &quot;destroy&quot; an array |
|!= 0 |attemt to display a non-existent function with ''-f'' |
===== Notes =====
Unix shells offer very few datatypes. Bash and some other shells extend this by allowing &quot;attributes&quot; to be set on variable names. The only attributes specified by POSIX are ''export'' and ''readonly'', which are set by their own dedicated builtins. Datatypes in bash have a few other interesting capabilities such as the ability to modify data on assignment.
===== Examples =====
==== Display defined functions ====
''declare -f'' can be used to display all defined functions...
&lt;code&gt;
$ declare -f
foo ()
{
echo &quot;FOO is BAR&quot;
}
world ()
{
echo &quot;Hello World!&quot;
}
&lt;/code&gt;
...or just a specific defined function.
&lt;code&gt;
$ declare -f foo
foo ()
{
echo &quot;FOO is BAR&quot;
}
&lt;/code&gt;
==== Nameref ====
Bash 4.3 adds a new way to indirectly reference variables. ''typeset -n'' can be used to make a variable indirectly refer to another. In Bash, the lvalue of the assignment given to ''typeset -n'' will refer to the variable whose name is expanded on the RHS.
&lt;code&gt;
# Sum a set of arrays and assign the result indirectly, also printing each intermediary result (without portability workarounds)
# sum name arrname [ arrname ... ]
function sum {
typeset -n _result=$1 _arr
typeset IFS=+
_result=0
for _arr in &quot;${@:2}&quot;; do # Demonstrate the special property of &quot;for&quot; on a nameref.
(( _result += ${_arr[*]} ))
printf '%s = %d\n' &quot;${!_result}&quot; &quot;$_result&quot; # Demonstrate the special property of ${!ref} on a nameref.
done
}
a=(1 2 3) b=(6 5 4) c=(2 4 6)
sum total a b c
printf 'Final value of &quot;total&quot; is: %d\n' &quot;$total&quot;
&lt;/code&gt;
&lt;div hide&gt;
function sum {
typeset -n _result=$1
shift
typeset IFS=+ _arrx
_result=0
for _arrx in &quot;$@&quot;; do # Demonstrate the special property of &quot;for&quot; on a nameref.
typeset -n _arr=$_arrx
(( _result += ${_arr[*]} ))
printf '%s = %d\n' &quot;${!_result}&quot; &quot;$_result&quot; # Demonstrate the special property of ${!ref} on a nameref.
done
}
a=(1 2 3); b=(6 5 4); c=(2 4 6)
sum total a b c
printf 'Final value of &quot;total&quot; is: %d\n' &quot;$total&quot;
&lt;/div&gt;
''typeset -n'' is currently implemented in ksh93, mksh, and Bash 4.3. Bash and mksh's implementations are quite similar, but much different from ksh93's. See [[#portability_considerations | Portability considerations]] for details. ksh93 namerefs are much more powerful than Bash's.
===== Portability considerations =====
* ''declare'' is not specified by POSIX(r)
* ''declare'' is unique to Bash and totally non-portable with the possible exception of Zsh in Bash compatibility mode. Bash marks the synonym ''typeset'' as obsolete, which in Bash behaves identically to ''declare''. All other Korn-like shells use ''typeset'', so it probably isn't going away any time soon. Unfortunately, being a non-standard builtin, ''typeset'' differs significantly between shells. ksh93 also considers ''typeset'' a special builtin, while Bash does not - even in POSIX mode. If you use ''typeset'', you should attempt to only use it in portable ways.
* **todo** nameref portability...
===== See also =====
* [[syntax:arrays]]
* [[commands:builtin:readonly]]
* [[commands:builtin:unset]]
* [[http://austingroupbugs.net/view.php?id=351 | declaration commands]] will change the behavior of certain builtins such as ''export'' in the next version of POSIX.</textarea>
<div id="wiki__editbar" class="editBar">
<div id="size__ctl">
</div>
</div>
</div></form>
</div>
</div><!-- /content --></div>
</div>
</div>
<div class="small text-right">
<span class="docInfo">
<ul class="list-inline"><li><span class="iconify text-muted" data-icon="mdi:file-document-outline"></span> <span title="commands/builtin/declare.txt">commands/builtin/declare.txt</span></li><li><span class="iconify text-muted" data-icon="mdi:calendar"></span> Last modified: <span title="2013/04/14 20:11">2013/04/14 20:11</span></li><li class="text-muted">by <bdi>ormaaj</bdi></li></ul> </span>
</div>
</article>
</div>
</main>
<footer id="dw__footer" class="dw-container py-5 dokuwiki container-fluid">
<hr/>
<div align="center">
<h3><a target="_blank" href="http://web.archive.org/web/20220706172727/http://www.performing-databases.com/">This site is supported by Performing Databases - your experts for database administration</a></h3>
</div>
<hr/>
<div align="center">
<script async src="//web.archive.org/web/20220706172727js_/https://pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script>
<!-- BHORG_BOTTOM -->
<ins class="adsbygoogle" style="display:inline-block;width:728px;height:90px" data-ad-client="ca-pub-4658830517838678" data-ad-slot="1603598940"></ins>
<script>
(adsbygoogle = window.adsbygoogle || []).push({});
</script>
</div>
<!-- footer -->
<div class="dw-container small container-fluid mx-5">
<div class="footer-dw-title">
<div class="media">
<div class="media-left">
<img src="/web/20220706172727im_/https://wiki.bash-hackers.org/lib/tpl/bootstrap3/images/logo.png" alt="Bash Hackers Wiki" class="media-object" style="height:32px"/>
</div>
<div class="media-body">
<div class="row">
<div class="col-sm-2">
<h4 class="media-heading">Bash Hackers Wiki</h4>
<p>
</p>
</div>
<div class="col-sm-10">
</div>
</div>
</div>
</div>
</div>
<div class="footer-license row">
<hr/>
<div id="dw__license" class="col-sm-6">
<p>
<a href="http://web.archive.org/web/20220706172727/http://www.gnu.org/licenses/fdl-1.3.html" title="GNU Free Documentation License 1.3" target="" itemscope itemtype="http://schema.org/CreativeWork" itemprop="license" rel="license" class="license"><img src="/web/20220706172727im_/https://wiki.bash-hackers.org/lib/tpl/bootstrap3/images/license/gnufdl.png" width="24" height="24" alt="gnufdl"/> </a> </p>
<p class="small">
Except where otherwise noted, content on this wiki is licensed under the following license:<br/><a href="http://web.archive.org/web/20220706172727/http://www.gnu.org/licenses/fdl-1.3.html" title="GNU Free Documentation License 1.3" target="" itemscope itemtype="http://schema.org/CreativeWork" itemprop="license" rel="license" class="license">GNU Free Documentation License 1.3</a> </p>
</div>
<div class="col-sm-6">
</div>
</div>
</div>
<!-- /footer -->
</footer>
<a href="#dokuwiki__top" class="back-to-top hidden-print btn btn-default" title="skip to content" accesskey="t">
<span class="iconify" data-icon="mdi:chevron-up"></span> </a>
<div id="screen__mode"> <span class="visible-xs-block"></span>
<span class="visible-sm-block"></span>
<span class="visible-md-block"></span>
<span class="visible-lg-block"></span>
</div>
<img src="/web/20220706172727im_/https://wiki.bash-hackers.org/lib/exe/indexer.php?id=commands%3Abuiltin%3Adeclare&amp;1657128449" width="2" height="1" alt=""/>
</div>
</body>
</html>
<!--
FILE ARCHIVED ON 17:27:27 Jul 06, 2022 AND RETRIEVED FROM THE
INTERNET ARCHIVE ON 11:36:51 Apr 14, 2023.
JAVASCRIPT APPENDED BY WAYBACK MACHINE, COPYRIGHT INTERNET ARCHIVE.
ALL OTHER CONTENT MAY ALSO BE PROTECTED BY COPYRIGHT (17 U.S.C.
SECTION 108(a)(3)).
-->
<!--
playback timings (ms):
captures_list: 1045.01
exclusion.robots: 0.109
exclusion.robots.policy: 0.101
cdx.remote: 0.051
esindex: 0.009
LoadShardBlock: 1005.522 (3)
PetaboxLoader3.datanode: 163.597 (4)
PetaboxLoader3.resolve: 911.867 (3)
load_resource: 139.083
-->
Reference in New Issue Copy Permalink