<!DOCTYPE html SYSTEM "about:legacy-compat">
<html lang="en"><head><META http-equiv="Content-Type" content="text/html; charset=UTF-8">
<meta content="width=device-width, initial-scale=1" name="viewport">
<!--
        XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
              This file is generated from xml source: DO NOT EDIT
        XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
      -->
<title>mod_env - Apache HTTP Server Version 2.4</title>
<link href="../style/css/manual.css" rel="stylesheet" media="all" type="text/css" title="Main stylesheet">
<link href="../style/css/manual-loose-100pc.css" rel="alternate stylesheet" media="all" type="text/css" title="No Sidebar - Default font size">
<link href="../style/css/manual-print.css" rel="stylesheet" media="print" type="text/css"><link rel="stylesheet" type="text/css" href="../style/css/prettify.css">
<script src="../style/scripts/prettify.min.js">
</script>

<link href="../images/favicon.png" rel="shortcut icon"></head>
<body>
<div id="page-header">
<p class="menu"><a href="../mod/">Modules</a> | <a href="../mod/quickreference.html">Directives</a> | <a href="https://cwiki.apache.org/confluence/display/httpd/FAQ">FAQ</a> | <a href="../glossary.html">Glossary</a> | <a href="../sitemap.html">Sitemap</a> | <a href="https://bz.apache.org/bugzilla/enter_bug.cgi?product=Apache%20httpd-2">Report a bug</a></p>
<p class="apache">Apache HTTP Server Version 2.4</p>
<img alt="" src="../images/feather.png"></div>
<div class="up"><a href="./"><img title="<-" alt="<-" src="../images/left.gif"></a></div>
<div id="path">
<a href="https://www.apache.org/">Apache</a> &gt; <a href="https://httpd.apache.org/">HTTP Server</a> &gt; <a href="https://httpd.apache.org/docs/">Documentation</a> &gt; <a href="../">Version 2.4</a> &gt; <a href="./">Modules</a></div>
<div id="page-content">
<div id="preamble"><h1>Apache Module mod_env</h1>
<button aria-label="Toggle language list" class="lang-toggle"><svg xmlns="http://www.w3.org/2000/svg" stroke-width="2" stroke="currentColor" fill="none" viewBox="0 0 24 24" height="16" width="16"><circle r="10" cy="12" cx="12"/><line y2="12" x2="22" y1="12" x1="2"/><path d="M12 2a15.3 15.3 0 0 1 4 10 15.3 15.3 0 0 1-4 10 15.3 15.3 0 0 1-4-10 15.3 15.3 0 0 1 4-10z"/></svg></button>
<div class="toplang">
<p><span>Available Languages: </span><a href="../en/mod/mod_env.html" title="English">&nbsp;en&nbsp;</a> |
<a href="../fr/mod/mod_env.html" hreflang="fr" rel="alternate" title="Fran&ccedil;ais">&nbsp;fr&nbsp;</a> |
<a href="../ja/mod/mod_env.html" hreflang="ja" rel="alternate" title="Japanese">&nbsp;ja&nbsp;</a> |
<a href="../ko/mod/mod_env.html" hreflang="ko" rel="alternate" title="Korean">&nbsp;ko&nbsp;</a> |
<a href="../tr/mod/mod_env.html" hreflang="tr" rel="alternate" title="T&uuml;rk&ccedil;e">&nbsp;tr&nbsp;</a></p>
</div>
<table class="module"><tr><th><a href="module-dict.html#Description">Description:</a></th><td>Modifies the environment which is passed to CGI scripts and
SSI pages</td></tr>
<tr><th><a href="module-dict.html#Status">Status:</a></th><td>Base</td></tr>
<tr><th><a href="module-dict.html#ModuleIdentifier">Module&nbsp;Identifier:</a></th><td>env_module</td></tr>
<tr><th><a href="module-dict.html#SourceFile">Source&nbsp;File:</a></th><td>mod_env.c</td></tr></table>
<h3>Summary</h3>

    <p>This module allows for control of internal environment variables that
    are used by various Apache HTTP Server modules. These variables are also
    provided to CGI scripts as native system environment variables, and available
    for use in SSI pages. Environment variables may be passed from the shell
    which invoked the <code class="program"><a href="../programs/httpd.html">httpd</a></code> process. Alternatively,
    environment variables may be set or unset within the configuration process.</p>
</div>
<div id="quickview"><h3 class="directives">Directives</h3>
<ul id="toc">
<li><img alt="" src="../images/down.gif"> <a href="#passenv">PassEnv</a></li>
<li><img alt="" src="../images/down.gif"> <a href="#setenv">SetEnv</a></li>
<li><img alt="" src="../images/down.gif"> <a href="#unsetenv">UnsetEnv</a></li>
</ul>
<h3>Bugfix checklist</h3><ul class="seealso"><li><a href="https://www.apache.org/dist/httpd/CHANGES_2.4">httpd changelog</a></li><li><a href="https://bz.apache.org/bugzilla/buglist.cgi?bug_status=__open__&amp;list_id=144532&amp;product=Apache%20httpd-2&amp;query_format=specific&amp;order=changeddate%20DESC%2Cpriority%2Cbug_severity&amp;component=mod_env">Known issues</a></li><li><a href="https://bz.apache.org/bugzilla/enter_bug.cgi?product=Apache%20httpd-2&amp;component=mod_env">Report a bug</a></li></ul><h3>See also</h3>
<ul class="seealso">
<li><a href="../env.html">Environment Variables</a></li>
<li><code class="directive"><a href="../mod/mod_setenvif.html#setenvif">SetEnvIf</a></code></li>
</ul></div>

<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif"></a></div>
<div class="directive-section"><h2 id="passenv"><span id="PassEnv">PassEnv</span> Directive <a title="Permanent link" href="#passenv" class="permalink">&para;</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Passes environment variables from the shell</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>PassEnv <var>env-variable</var> [<var>env-variable</var>]
...</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Base</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_env</td></tr>
</table>
    <p>Specifies one or more native system environment variables to make available
    as internal environment variables, which are available to Apache HTTP Server modules
    as well as propagated to CGI scripts and SSI pages. Values come from the
    native OS environment of the shell which invoked the
    <code class="program"><a href="../programs/httpd.html">httpd</a></code> process.</p>

    <div class="example"><h3>Example</h3><pre class="prettyprint lang-config">PassEnv LD_LIBRARY_PATH</pre>
</div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif"></a></div>
<div class="directive-section"><h2 id="setenv"><span id="SetEnv">SetEnv</span> Directive <a title="Permanent link" href="#setenv" class="permalink">&para;</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Sets environment variables</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SetEnv <var>env-variable</var> [<var>value</var>]</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Base</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_env</td></tr>
</table>
    <p>Sets an internal environment variable, which is then available to Apache
    HTTP Server modules, and passed on to CGI scripts and SSI pages.</p>

    <div class="example"><h3>Example</h3><pre class="prettyprint lang-config">SetEnv SPECIAL_PATH /foo/bin</pre>
</div>
 
    <p> If you omit the <var>value</var> argument, the variable is set to
    an empty string.</p>

    <div class="note"><p>The internal environment variables set by this directive are set
    <em>after</em> most early request processing directives are run, such as access
    control and URI-to-filename mapping.  If the environment variable you're
    setting is meant as input into this early phase of processing such as the
    <code class="directive"><a href="../mod/mod_rewrite.html#rewriterule">RewriteRule</a></code> directive, you should
    instead set the environment variable with
    <code class="directive"><a href="../mod/mod_setenvif.html#setenvif">SetEnvIf</a></code>.</p>
    </div>


<h3>See also</h3>
<ul>
<li><a href="../env.html">Environment Variables</a></li>
</ul>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif"></a></div>
<div class="directive-section"><h2 id="unsetenv"><span id="UnsetEnv">UnsetEnv</span> Directive <a title="Permanent link" href="#unsetenv" class="permalink">&para;</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Removes variables from the environment</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>UnsetEnv <var>env-variable</var> [<var>env-variable</var>]
...</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Base</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_env</td></tr>
</table>
    <p>Removes one or more internal environment variables from those passed
    on to CGI scripts and SSI pages.</p>

    <div class="example"><h3>Example</h3><pre class="prettyprint lang-config">UnsetEnv LD_LIBRARY_PATH</pre>
</div>

</div>
</div>
<div class="bottomlang">
<p><span>Available Languages: </span><a href="../en/mod/mod_env.html" title="English">&nbsp;en&nbsp;</a> |
<a href="../fr/mod/mod_env.html" hreflang="fr" rel="alternate" title="Fran&ccedil;ais">&nbsp;fr&nbsp;</a> |
<a href="../ja/mod/mod_env.html" hreflang="ja" rel="alternate" title="Japanese">&nbsp;ja&nbsp;</a> |
<a href="../ko/mod/mod_env.html" hreflang="ko" rel="alternate" title="Korean">&nbsp;ko&nbsp;</a> |
<a href="../tr/mod/mod_env.html" hreflang="tr" rel="alternate" title="T&uuml;rk&ccedil;e">&nbsp;tr&nbsp;</a></p>
</div><div id="footer">
<p class="apache">Copyright 2026 The Apache Software Foundation.<br>Licensed under the <a href="https://www.apache.org/licenses/LICENSE-2.0">Apache License, Version 2.0</a>.</p>
<p class="menu"><a href="../mod/">Modules</a> | <a href="../mod/quickreference.html">Directives</a> | <a href="https://cwiki.apache.org/confluence/display/httpd/FAQ">FAQ</a> | <a href="../glossary.html">Glossary</a> | <a href="../sitemap.html">Sitemap</a> | <a href="https://bz.apache.org/bugzilla/enter_bug.cgi?product=Apache%20httpd-2">Report a bug</a></p></div><script><!--//--><![CDATA[//><!--
if (typeof(prettyPrint) !== 'undefined') {
    prettyPrint();
}
var langToggle = document.querySelector('.lang-toggle');
var topLang = document.querySelector('.toplang');
if (langToggle && topLang) {
    langToggle.addEventListener('click', function() { topLang.classList.toggle('open'); });
}
var qv = document.getElementById('quickview');
if (qv) {
    document.body.appendChild(qv);
    var qvBtn = document.createElement('button');
    qvBtn.className = 'qv-toggle';
    qvBtn.setAttribute('aria-label', 'Toggle page navigation');
    qvBtn.innerHTML = '&#9776;';
    document.body.appendChild(qvBtn);
    qvBtn.addEventListener('click', function() {
        var isOpen = qv.classList.toggle('open');
        if (isOpen) {
            qv.style.top = window.scrollY + 10 + 'px';
        }
    });
    window.addEventListener('scroll', function() { qv.classList.remove('open'); });
}
//--><!]]></script>
</body></html>