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			1377 lines
		
	
	
		
			66 KiB
		
	
	
	
		
			XML
		
	
	
	
	
	
<?xml version="1.0" encoding="ISO-8859-1"?>
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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
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<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"><head><!--
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              This file is generated from xml source: DO NOT EDIT
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      -->
 | 
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<title>mod_rewrite - Apache HTTP Server</title>
 | 
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<link href="../style/css/manual.css" rel="stylesheet" media="all" type="text/css" title="Main stylesheet" />
 | 
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<link href="../style/css/manual-loose-100pc.css" rel="alternate stylesheet" media="all" type="text/css" title="No Sidebar - Default font size" />
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<link href="../style/css/manual-print.css" rel="stylesheet" media="print" type="text/css" />
 | 
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<link href="../images/favicon.ico" rel="shortcut icon" /></head>
 | 
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<body>
 | 
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<div id="page-header">
 | 
						||
<p class="menu"><a href="../mod/">Modules</a> | <a href="../mod/directives.html">Directives</a> | <a href="../faq/">FAQ</a> | <a href="../glossary.html">Glossary</a> | <a href="../sitemap.html">Sitemap</a></p>
 | 
						||
<p class="apache">Apache HTTP Server Version 2.3</p>
 | 
						||
<img alt="" src="../images/feather.gif" /></div>
 | 
						||
<div class="up"><a href="./"><img title="<-" alt="<-" src="../images/left.gif" /></a></div>
 | 
						||
<div id="path">
 | 
						||
<a href="http://www.apache.org/">Apache</a> > <a href="http://httpd.apache.org/">HTTP Server</a> > <a href="http://httpd.apache.org/docs/">Documentation</a> > <a href="../">Version 2.3</a> > <a href="./">Modules</a></div>
 | 
						||
<div id="page-content">
 | 
						||
<div id="preamble"><h1>Apache Module mod_rewrite</h1>
 | 
						||
<div class="toplang">
 | 
						||
<p><span>Available Languages: </span><a href="../en/mod/mod_rewrite.html" title="English"> en </a> |
 | 
						||
<a href="../fr/mod/mod_rewrite.html" hreflang="fr" rel="alternate" title="Français"> fr </a></p>
 | 
						||
</div>
 | 
						||
<table class="module"><tr><th><a href="module-dict.html#Description">Description:</a></th><td>Provides a rule-based rewriting engine to rewrite requested
 | 
						||
URLs on the fly</td></tr>
 | 
						||
<tr><th><a href="module-dict.html#Status">Status:</a></th><td>Extension</td></tr>
 | 
						||
<tr><th><a href="module-dict.html#ModuleIdentifier">Module Identifier:</a></th><td>rewrite_module</td></tr>
 | 
						||
<tr><th><a href="module-dict.html#SourceFile">Source File:</a></th><td>mod_rewrite.c</td></tr>
 | 
						||
<tr><th><a href="module-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 1.3 and later</td></tr></table>
 | 
						||
<h3>Summary</h3>
 | 
						||
 | 
						||
	<p>The <code class="module"><a href="../mod/mod_rewrite.html">mod_rewrite</a></code> module uses a rule-based rewriting 
 | 
						||
      engine, based on a regular-expression parser, to rewrite requested URLs on
 | 
						||
      the fly. By default, <code class="module"><a href="../mod/mod_rewrite.html">mod_rewrite</a></code> maps a URL to a filesystem 
 | 
						||
      path. However, it can also be used to redirect one URL to another URL, or
 | 
						||
      to invoke an internal proxy fetch.</p>
 | 
						||
      <p><code class="module"><a href="../mod/mod_rewrite.html">mod_rewrite</a></code> provides a flexible and powerful way to 
 | 
						||
      manipulate URLs using an unlimited number of rules. Each rule can have an 
 | 
						||
      unlimited number of attached rule conditions, to allow you to rewrite URL
 | 
						||
      based on server variables, environment variables, HTTP headers, or time 
 | 
						||
      stamps.</p>
 | 
						||
      <p><code class="module"><a href="../mod/mod_rewrite.html">mod_rewrite</a></code> operates on the full URL path, including the
 | 
						||
      path-info section. A rewrite rule can be invoked in 
 | 
						||
      <code>httpd.conf</code> or in <code>.htaccess</code>. The path generated 
 | 
						||
      by a rewrite rule can include a query string, or can lead to internal 
 | 
						||
      sub-processing, external request redirection, or internal proxy 
 | 
						||
      throughput.</p>
 | 
						||
 | 
						||
      <p>Further details, discussion, and examples, are provided in the
 | 
						||
      <a href="../rewrite/">detailed mod_rewrite documentation</a>.</p>
 | 
						||
</div>
 | 
						||
<div id="quickview"><h3 class="directives">Directives</h3>
 | 
						||
<ul id="toc">
 | 
						||
<li><img alt="" src="../images/down.gif" /> <a href="#rewritebase">RewriteBase</a></li>
 | 
						||
<li><img alt="" src="../images/down.gif" /> <a href="#rewritecond">RewriteCond</a></li>
 | 
						||
<li><img alt="" src="../images/down.gif" /> <a href="#rewriteengine">RewriteEngine</a></li>
 | 
						||
<li><img alt="" src="../images/down.gif" /> <a href="#rewritelog">RewriteLog</a></li>
 | 
						||
<li><img alt="" src="../images/down.gif" /> <a href="#rewriteloglevel">RewriteLogLevel</a></li>
 | 
						||
<li><img alt="" src="../images/down.gif" /> <a href="#rewritemap">RewriteMap</a></li>
 | 
						||
<li><img alt="" src="../images/down.gif" /> <a href="#rewriteoptions">RewriteOptions</a></li>
 | 
						||
<li><img alt="" src="../images/down.gif" /> <a href="#rewriterule">RewriteRule</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><a name="RewriteBase" id="RewriteBase">RewriteBase</a> <a name="rewritebase" id="rewritebase">Directive</a></h2>
 | 
						||
<table class="directive">
 | 
						||
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Sets the base URL for per-directory rewrites</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>RewriteBase <em>URL-path</em></code></td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>None</code></td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>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>Extension</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_rewrite</td></tr>
 | 
						||
</table>
 | 
						||
      <p>The <code class="directive">RewriteBase</code> directive explicitly
 | 
						||
      sets the base URL-path (not filesystem directory path!)  for per-directory rewrites.
 | 
						||
      When you use a <code class="directive"><a href="#rewriterule">RewriteRule</a></code>
 | 
						||
      in a <code>.htaccess</code> file, <code class="module"><a href="../mod/mod_rewrite.html">mod_rewrite</a></code> strips off
 | 
						||
      the local directory prefix before processing, then rewrites the rest of 
 | 
						||
      the URL. When the rewrite is completed, <code class="module"><a href="../mod/mod_rewrite.html">mod_rewrite</a></code>
 | 
						||
      automatically adds the local directory prefix back on to the path.</p>
 | 
						||
      
 | 
						||
      <p>This directive is <em>required</em> for per-directory rewrites whose context
 | 
						||
      is a directory made available via the <code class="directive"><a href="../mod/mod_alias.html#alias">Alias</a></code>
 | 
						||
      directive.</p>
 | 
						||
 | 
						||
      <p>If your URL path does not exist verbatim on the filesystem,
 | 
						||
      or isn't directly under your <code class="directive"><a href="../mod/core.html#documentroot">DocumentRoot</a></code>,
 | 
						||
      you must use <code class="directive">RewriteBase</code> in every
 | 
						||
      <code>.htaccess</code> file where you want to use <code class="directive"><a href="#rewriterule">RewriteRule</a></code> directives.</p>
 | 
						||
 | 
						||
      <p>The example below demonstrates how to map 
 | 
						||
      http://example.com/myapp/index.html to 
 | 
						||
      /home/www/example/newsite.html, in a <code>.htaccess</code> file. This 
 | 
						||
      assumes that the content available at
 | 
						||
      http://example.com/ is on disk at /home/www/example/</p>
 | 
						||
<div class="example"><pre>
 | 
						||
RewriteEngine On
 | 
						||
# The URL-path used to get to this context, not the filesystem path
 | 
						||
RewriteBase /myapp/
 | 
						||
RewriteRule ^index\.html$  newsite.html
 | 
						||
</pre></div>
 | 
						||
 | 
						||
 | 
						||
</div>
 | 
						||
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
 | 
						||
<div class="directive-section"><h2><a name="RewriteCond" id="RewriteCond">RewriteCond</a> <a name="rewritecond" id="rewritecond">Directive</a></h2>
 | 
						||
<table class="directive">
 | 
						||
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Defines a condition under which rewriting will take place
 | 
						||
</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code> RewriteCond
 | 
						||
      <em>TestString</em> <em>CondPattern</em></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>Extension</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_rewrite</td></tr>
 | 
						||
</table>
 | 
						||
      <p>The <code class="directive">RewriteCond</code> directive defines a
 | 
						||
      rule condition. One or more <code class="directive">RewriteCond</code>
 | 
						||
      can precede a <code class="directive"><a href="#rewriterule">RewriteRule</a></code>
 | 
						||
      directive. The following rule is then only used if both
 | 
						||
      the current state of the URI matches its pattern, <strong>and</strong> if these conditions are met.</p>
 | 
						||
 | 
						||
      <p><em>TestString</em> is a string which can contain the
 | 
						||
      following expanded constructs in addition to plain text:</p>
 | 
						||
 | 
						||
      <ul>
 | 
						||
        <li>
 | 
						||
          <strong>RewriteRule backreferences</strong>: These are
 | 
						||
          backreferences of the form <strong><code>$N</code></strong>
 | 
						||
          (0 <= N <= 9). $1 to $9 provide access to the grouped
 | 
						||
          parts (in parentheses) of the pattern, from the
 | 
						||
          <code>RewriteRule</code> which is subject to the current
 | 
						||
          set of <code>RewriteCond</code> conditions. $0 provides
 | 
						||
          access to the whole string matched by that pattern.
 | 
						||
        </li>
 | 
						||
        <li>
 | 
						||
          <strong>RewriteCond backreferences</strong>: These are
 | 
						||
          backreferences of the form <strong><code>%N</code></strong>
 | 
						||
          (0 <= N <= 9). %1 to %9 provide access to the grouped
 | 
						||
          parts (again, in parentheses) of the pattern, from the last matched
 | 
						||
          <code>RewriteCond</code> in the current set
 | 
						||
          of conditions. %0 provides access to the whole string matched by
 | 
						||
          that pattern.
 | 
						||
        </li>
 | 
						||
        <li>
 | 
						||
          <strong>RewriteMap expansions</strong>: These are
 | 
						||
          expansions of the form <strong><code>${mapname:key|default}</code></strong>.
 | 
						||
          See <a href="#mapfunc">the documentation for
 | 
						||
          RewriteMap</a> for more details.
 | 
						||
        </li>
 | 
						||
        <li>
 | 
						||
          <strong>Server-Variables</strong>: These are variables of
 | 
						||
          the form
 | 
						||
            <strong><code>%{</code> <em>NAME_OF_VARIABLE</em>
 | 
						||
            <code>}</code></strong>
 | 
						||
          where <em>NAME_OF_VARIABLE</em> can be a string taken
 | 
						||
          from the following list:
 | 
						||
 | 
						||
          <table>
 | 
						||
          
 | 
						||
            <tr>
 | 
						||
              <th>HTTP headers:</th> <th>connection & request:</th> <th />
 | 
						||
            </tr>
 | 
						||
 | 
						||
            <tr>
 | 
						||
              <td>
 | 
						||
                 HTTP_USER_AGENT<br />
 | 
						||
                 HTTP_REFERER<br />
 | 
						||
                 HTTP_COOKIE<br />
 | 
						||
                 HTTP_FORWARDED<br />
 | 
						||
                 HTTP_HOST<br />
 | 
						||
                 HTTP_PROXY_CONNECTION<br />
 | 
						||
                 HTTP_ACCEPT<br />
 | 
						||
              </td>
 | 
						||
 | 
						||
              <td>
 | 
						||
                 REMOTE_ADDR<br />
 | 
						||
                 REMOTE_HOST<br />
 | 
						||
                 REMOTE_PORT<br />
 | 
						||
                 REMOTE_USER<br />
 | 
						||
                 REMOTE_IDENT<br />
 | 
						||
                 REQUEST_METHOD<br />
 | 
						||
                 SCRIPT_FILENAME<br />
 | 
						||
                 PATH_INFO<br />
 | 
						||
                 QUERY_STRING<br />
 | 
						||
                 AUTH_TYPE<br />
 | 
						||
              </td>
 | 
						||
 | 
						||
              <td />
 | 
						||
            </tr>
 | 
						||
 | 
						||
            <tr>
 | 
						||
              <th>server internals:</th> <th>date and time:</th> <th>specials:</th>
 | 
						||
            </tr>
 | 
						||
 | 
						||
            <tr>
 | 
						||
              <td>
 | 
						||
                 DOCUMENT_ROOT<br />
 | 
						||
                 SERVER_ADMIN<br />
 | 
						||
                 SERVER_NAME<br />
 | 
						||
                 SERVER_ADDR<br />
 | 
						||
                 SERVER_PORT<br />
 | 
						||
                 SERVER_PROTOCOL<br />
 | 
						||
                 SERVER_SOFTWARE<br />
 | 
						||
              </td>
 | 
						||
 | 
						||
              <td>
 | 
						||
                 TIME_YEAR<br />
 | 
						||
                 TIME_MON<br />
 | 
						||
                 TIME_DAY<br />
 | 
						||
                 TIME_HOUR<br />
 | 
						||
                 TIME_MIN<br />
 | 
						||
                 TIME_SEC<br />
 | 
						||
                 TIME_WDAY<br />
 | 
						||
                 TIME<br />
 | 
						||
              </td>
 | 
						||
 | 
						||
              <td>
 | 
						||
                 API_VERSION<br />
 | 
						||
                 THE_REQUEST<br />
 | 
						||
                 REQUEST_URI<br />
 | 
						||
                 REQUEST_FILENAME<br />
 | 
						||
                 IS_SUBREQ<br />
 | 
						||
                 HTTPS<br />
 | 
						||
              </td>
 | 
						||
            </tr>
 | 
						||
          </table>
 | 
						||
 | 
						||
                <p>These variables all
 | 
						||
                correspond to the similarly named HTTP
 | 
						||
                MIME-headers, C variables of the Apache server or
 | 
						||
                <code>struct tm</code> fields of the Unix system.
 | 
						||
                Most are documented elsewhere in the Manual or in
 | 
						||
                the CGI specification. Those that are special to
 | 
						||
                mod_rewrite include those below.</p>
 | 
						||
        <div class="note">
 | 
						||
                <dl>
 | 
						||
                  <dt><code>IS_SUBREQ</code></dt>
 | 
						||
 | 
						||
                  <dd>Will contain the text "true" if the request
 | 
						||
                  currently being processed is a sub-request,
 | 
						||
                  "false" otherwise. Sub-requests may be generated
 | 
						||
                  by modules that need to resolve additional files
 | 
						||
                  or URIs in order to complete their tasks.</dd>
 | 
						||
 | 
						||
                  <dt><code>API_VERSION</code></dt>
 | 
						||
 | 
						||
                  <dd>This is the version of the Apache module API
 | 
						||
                  (the internal interface between server and
 | 
						||
                  module) in the current httpd build, as defined in
 | 
						||
                  include/ap_mmn.h. The module API version
 | 
						||
                  corresponds to the version of Apache in use (in
 | 
						||
                  the release version of Apache 1.3.14, for
 | 
						||
                  instance, it is 19990320:10), but is mainly of
 | 
						||
                  interest to module authors.</dd>
 | 
						||
 | 
						||
                  <dt><code>THE_REQUEST</code></dt>
 | 
						||
 | 
						||
                  <dd>The full HTTP request line sent by the
 | 
						||
                  browser to the server (e.g., "<code>GET
 | 
						||
                  /index.html HTTP/1.1</code>"). This does not
 | 
						||
                  include any additional headers sent by the
 | 
						||
                  browser.</dd>
 | 
						||
 | 
						||
                  <dt><code>REQUEST_URI</code></dt>
 | 
						||
 | 
						||
                  <dd>The resource requested in the HTTP request
 | 
						||
                  line. (In the example above, this would be
 | 
						||
                  "/index.html".)</dd>
 | 
						||
 | 
						||
                  <dt><code>REQUEST_FILENAME</code></dt>
 | 
						||
 | 
						||
                  <dd>The full local filesystem path to the file or
 | 
						||
                  script matching the request, if this has already
 | 
						||
                  been determined by the server at the time 
 | 
						||
                  <code>REQUEST_FILENAME</code> is referenced. Otherwise, 
 | 
						||
                  such as when used in virtual host context, the same 
 | 
						||
                  value as <code>REQUEST_URI</code>.</dd>
 | 
						||
 | 
						||
                  <dt><code>HTTPS</code></dt>
 | 
						||
 | 
						||
                  <dd>Will contain the text "on" if the connection is
 | 
						||
                  using SSL/TLS, or "off" otherwise.  (This variable
 | 
						||
                  can be safely used regardless of whether or not
 | 
						||
                  <code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code> is loaded).</dd>
 | 
						||
 | 
						||
                </dl>
 | 
						||
</div>
 | 
						||
        </li>
 | 
						||
      </ul>
 | 
						||
 | 
						||
      <p>Other things you should be aware of:</p>
 | 
						||
 | 
						||
      <ol>
 | 
						||
        <li>
 | 
						||
        <p>The variables SCRIPT_FILENAME and REQUEST_FILENAME
 | 
						||
        contain the same value - the value of the
 | 
						||
        <code>filename</code> field of the internal
 | 
						||
        <code>request_rec</code> structure of the Apache server.
 | 
						||
        The first name is the commonly known CGI variable name
 | 
						||
        while the second is the appropriate counterpart of
 | 
						||
        REQUEST_URI (which contains the value of the
 | 
						||
        <code>uri</code> field of <code>request_rec</code>).</p>
 | 
						||
        <p>If a substitution occurred and the rewriting continues,
 | 
						||
        the value of both variables will be updated accordingly.</p>
 | 
						||
        <p>If used in per-server context (<em>i.e.</em>, before the
 | 
						||
        request is mapped to the filesystem) SCRIPT_FILENAME and
 | 
						||
        REQUEST_FILENAME cannot contain the full local filesystem
 | 
						||
        path since the path is unknown at this stage of processing.
 | 
						||
        Both variables will initially contain the value of REQUEST_URI
 | 
						||
        in that case. In order to obtain the full local filesystem
 | 
						||
        path of the request in per-server context, use an URL-based
 | 
						||
        look-ahead <code>%{LA-U:REQUEST_FILENAME}</code> to determine
 | 
						||
        the final value of REQUEST_FILENAME.</p></li>
 | 
						||
 | 
						||
        <li>
 | 
						||
        <code>%{ENV:variable}</code>, where <em>variable</em> can be
 | 
						||
        any environment variable, is also available.
 | 
						||
        This is looked-up via internal
 | 
						||
        Apache structures and (if not found there) via
 | 
						||
        <code>getenv()</code> from the Apache server process.</li>
 | 
						||
 | 
						||
        <li>
 | 
						||
        <code>%{SSL:variable}</code>, where <em>variable</em> is the
 | 
						||
        name of an <a href="mod_ssl.html#envvars">SSL environment
 | 
						||
        variable</a>, can be used whether or not
 | 
						||
        <code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code> is loaded, but will always expand to
 | 
						||
        the empty string if it is not.  Example:
 | 
						||
        <code>%{SSL:SSL_CIPHER_USEKEYSIZE}</code> may expand to
 | 
						||
        <code>128</code>.</li>
 | 
						||
 | 
						||
        <li>
 | 
						||
        <code>%{HTTP:header}</code>, where <em>header</em> can be
 | 
						||
        any HTTP MIME-header name, can always be used to obtain the
 | 
						||
        value of a header sent in the HTTP request.
 | 
						||
        Example: <code>%{HTTP:Proxy-Connection}</code> is
 | 
						||
        the value of the HTTP header
 | 
						||
        ``<code>Proxy-Connection:</code>''.
 | 
						||
        <p>If a HTTP header is used in a condition this header is added to
 | 
						||
        the Vary header of the response in case the condition evaluates to
 | 
						||
        to true for the request. It is <strong>not</strong> added if the
 | 
						||
        condition evaluates to false for the request. Adding the HTTP header
 | 
						||
        to the Vary header of the response is needed for proper caching.</p>
 | 
						||
        <p>It has to be kept in mind that conditions follow a short circuit
 | 
						||
        logic in the case of the '<strong><code>ornext|OR</code></strong>' flag
 | 
						||
        so that certain conditions might not be evaluated at all.</p></li>
 | 
						||
 | 
						||
        <li>
 | 
						||
        <code>%{LA-U:variable}</code> can be used for look-aheads which perform
 | 
						||
        an internal (URL-based) sub-request to determine the final
 | 
						||
        value of <em>variable</em>. This can be used to access
 | 
						||
        variable for rewriting which is not available at the current
 | 
						||
        stage, but will be set in a later phase.
 | 
						||
        <p>For instance, to rewrite according to the
 | 
						||
        <code>REMOTE_USER</code> variable from within the
 | 
						||
        per-server context (<code>httpd.conf</code> file) you must
 | 
						||
        use <code>%{LA-U:REMOTE_USER}</code> - this
 | 
						||
        variable is set by the authorization phases, which come
 | 
						||
        <em>after</em> the URL translation phase (during which mod_rewrite
 | 
						||
        operates).</p>
 | 
						||
        <p>On the other hand, because mod_rewrite implements
 | 
						||
        its per-directory context (<code>.htaccess</code> file) via
 | 
						||
        the Fixup phase of the API and because the authorization
 | 
						||
        phases come <em>before</em> this phase, you just can use
 | 
						||
        <code>%{REMOTE_USER}</code> in that context.</p></li>
 | 
						||
 | 
						||
        <li>
 | 
						||
        <code>%{LA-F:variable}</code> can be used to perform an internal
 | 
						||
        (filename-based) sub-request, to determine the final value
 | 
						||
        of <em>variable</em>. Most of the time, this is the same as
 | 
						||
        LA-U above.</li>
 | 
						||
      </ol>
 | 
						||
 | 
						||
      <p><em>CondPattern</em> is the condition pattern,
 | 
						||
       a regular expression which is applied to the
 | 
						||
      current instance of the <em>TestString</em>.
 | 
						||
      <em>TestString</em> is first evaluated, before being matched against
 | 
						||
      <em>CondPattern</em>.</p>
 | 
						||
 | 
						||
      <p><strong>Remember:</strong> <em>CondPattern</em> is a
 | 
						||
      <em>perl compatible regular expression</em> with some
 | 
						||
      additions:</p>
 | 
						||
 | 
						||
      <ol>
 | 
						||
        <li>You can prefix the pattern string with a
 | 
						||
        '<code>!</code>' character (exclamation mark) to specify a
 | 
						||
        <strong>non</strong>-matching pattern.</li>
 | 
						||
 | 
						||
        <li>
 | 
						||
          There are some special variants of <em>CondPatterns</em>.
 | 
						||
          Instead of real regular expression strings you can also
 | 
						||
          use one of the following:
 | 
						||
 | 
						||
          <ul>
 | 
						||
            <li>'<strong><CondPattern</strong>' (lexicographically
 | 
						||
            precedes)<br />
 | 
						||
            Treats the <em>CondPattern</em> as a plain string and
 | 
						||
            compares it lexicographically to <em>TestString</em>. True if
 | 
						||
            <em>TestString</em> lexicographically precedes
 | 
						||
            <em>CondPattern</em>.</li>
 | 
						||
 | 
						||
            <li>'<strong>>CondPattern</strong>' (lexicographically
 | 
						||
            follows)<br />
 | 
						||
            Treats the <em>CondPattern</em> as a plain string and
 | 
						||
            compares it lexicographically to <em>TestString</em>. True if
 | 
						||
            <em>TestString</em> lexicographically follows
 | 
						||
            <em>CondPattern</em>.</li>
 | 
						||
 | 
						||
            <li>'<strong>=CondPattern</strong>' (lexicographically
 | 
						||
            equal)<br />
 | 
						||
            Treats the <em>CondPattern</em> as a plain string and
 | 
						||
            compares it lexicographically to <em>TestString</em>. True if
 | 
						||
            <em>TestString</em> is lexicographically equal to
 | 
						||
            <em>CondPattern</em> (the two strings are exactly
 | 
						||
            equal, character for character). If <em>CondPattern</em>
 | 
						||
            is <code>""</code> (two quotation marks) this
 | 
						||
            compares <em>TestString</em> to the empty string.</li>
 | 
						||
 | 
						||
            <li>'<strong>-d</strong>' (is
 | 
						||
            <strong>d</strong>irectory)<br />
 | 
						||
             Treats the <em>TestString</em> as a pathname and tests
 | 
						||
            whether or not it exists, and is a directory.</li>
 | 
						||
 | 
						||
            <li>'<strong>-f</strong>' (is regular
 | 
						||
            <strong>f</strong>ile)<br />
 | 
						||
             Treats the <em>TestString</em> as a pathname and tests
 | 
						||
            whether or not it exists, and is a regular file.</li>
 | 
						||
 | 
						||
            <li>'<strong>-s</strong>' (is regular file, with
 | 
						||
            <strong>s</strong>ize)<br />
 | 
						||
            Treats the <em>TestString</em> as a pathname and tests
 | 
						||
            whether or not it exists, and is a regular file with size greater
 | 
						||
            than zero.</li>
 | 
						||
 | 
						||
            <li>'<strong>-l</strong>' (is symbolic
 | 
						||
            <strong>l</strong>ink)<br />
 | 
						||
            Treats the <em>TestString</em> as a pathname and tests
 | 
						||
            whether or not it exists, and is a symbolic link.</li>
 | 
						||
 | 
						||
            <li>'<strong>-x</strong>' (has e<strong>x</strong>ecutable
 | 
						||
            permissions)<br />
 | 
						||
            Treats the <em>TestString</em> as a pathname and tests
 | 
						||
            whether or not it exists, and has executable permissions.
 | 
						||
            These permissions are determined according to
 | 
						||
            the underlying OS.</li>
 | 
						||
 | 
						||
            <li>'<strong>-F</strong>' (is existing file, via
 | 
						||
            subrequest)<br />
 | 
						||
            Checks whether or not <em>TestString</em> is a valid file,
 | 
						||
            accessible via all the server's currently-configured
 | 
						||
            access controls for that path. This uses an internal
 | 
						||
            subrequest to do the check, so use it with care -
 | 
						||
            it can impact your server's performance!</li>
 | 
						||
 | 
						||
            <li>'<strong>-U</strong>' (is existing URL, via
 | 
						||
            subrequest)<br />
 | 
						||
            Checks whether or not <em>TestString</em> is a valid URL,
 | 
						||
            accessible via all the server's currently-configured
 | 
						||
            access controls for that path. This uses an internal
 | 
						||
            subrequest to do the check, so use it with care -
 | 
						||
            it can impact your server's performance!</li>
 | 
						||
          </ul>
 | 
						||
 | 
						||
<div class="note"><h3>Note:</h3>
 | 
						||
              All of these tests can
 | 
						||
              also be prefixed by an exclamation mark ('!') to
 | 
						||
              negate their meaning.
 | 
						||
</div>
 | 
						||
        </li>
 | 
						||
 | 
						||
        <li>You can also set special flags for
 | 
						||
      <em>CondPattern</em> by appending
 | 
						||
        <strong><code>[</code><em>flags</em><code>]</code></strong>
 | 
						||
      as the third argument to the <code>RewriteCond</code>
 | 
						||
      directive, where <em>flags</em> is a comma-separated list of any of the
 | 
						||
      following flags:
 | 
						||
 | 
						||
      <ul>
 | 
						||
        <li>'<strong><code>nocase|NC</code></strong>'
 | 
						||
        (<strong>n</strong>o <strong>c</strong>ase)<br />
 | 
						||
        This makes the test case-insensitive - differences
 | 
						||
        between 'A-Z' and 'a-z' are ignored, both in the
 | 
						||
        expanded <em>TestString</em> and the <em>CondPattern</em>.
 | 
						||
        This flag is effective only for comparisons between
 | 
						||
        <em>TestString</em> and <em>CondPattern</em>. It has no
 | 
						||
        effect on filesystem and subrequest checks.</li>
 | 
						||
 | 
						||
        <li>
 | 
						||
          '<strong><code>ornext|OR</code></strong>'
 | 
						||
          (<strong>or</strong> next condition)<br />
 | 
						||
          Use this to combine rule conditions with a local OR
 | 
						||
          instead of the implicit AND. Typical example:
 | 
						||
 | 
						||
<div class="example"><pre>
 | 
						||
RewriteCond %{REMOTE_HOST}  ^host1.*  [OR]
 | 
						||
RewriteCond %{REMOTE_HOST}  ^host2.*  [OR]
 | 
						||
RewriteCond %{REMOTE_HOST}  ^host3.*
 | 
						||
RewriteRule ...some special stuff for any of these hosts...
 | 
						||
</pre></div>
 | 
						||
 | 
						||
          Without this flag you would have to write the condition/rule
 | 
						||
          pair three times.
 | 
						||
        </li>
 | 
						||
 | 
						||
        <li>'<strong><code>novary|NV</code></strong>'
 | 
						||
        (<strong>n</strong>o <strong>v</strong>ary)<br />
 | 
						||
        If a HTTP header is used in the condition, this flag prevents
 | 
						||
        this header from being added to the Vary header of the response. <br />
 | 
						||
        Using this flag might break proper caching of the response if
 | 
						||
        the representation of this response varies on the value of this header.
 | 
						||
        So this flag should be only used if the meaning of the Vary header
 | 
						||
        is well understood.
 | 
						||
        </li>
 | 
						||
      </ul>
 | 
						||
      </li>
 | 
						||
     </ol>
 | 
						||
 | 
						||
      <p><strong>Example:</strong></p>
 | 
						||
 | 
						||
       <p>To rewrite the Homepage of a site according to the
 | 
						||
        ``<code>User-Agent:</code>'' header of the request, you can
 | 
						||
        use the following: </p>
 | 
						||
 | 
						||
<div class="example"><pre>
 | 
						||
RewriteCond  %{HTTP_USER_AGENT}  ^Mozilla.*
 | 
						||
RewriteRule  ^/$                 /homepage.max.html  [L]
 | 
						||
 | 
						||
RewriteCond  %{HTTP_USER_AGENT}  ^Lynx.*
 | 
						||
RewriteRule  ^/$                 /homepage.min.html  [L]
 | 
						||
 | 
						||
RewriteRule  ^/$                 /homepage.std.html  [L]
 | 
						||
</pre></div>
 | 
						||
 | 
						||
        <p>Explanation: If you use a browser which identifies itself
 | 
						||
        as 'Mozilla' (including Netscape Navigator, Mozilla etc), then you
 | 
						||
        get the max homepage (which could include frames, or other special
 | 
						||
        features).
 | 
						||
        If you use the Lynx browser (which is terminal-based), then
 | 
						||
        you get the min homepage (which could be a version designed for
 | 
						||
        easy, text-only browsing).
 | 
						||
        If neither of these conditions apply (you use any other browser,
 | 
						||
        or your browser identifies itself as something non-standard), you get
 | 
						||
        the std (standard) homepage.</p>
 | 
						||
 | 
						||
 | 
						||
</div>
 | 
						||
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
 | 
						||
<div class="directive-section"><h2><a name="RewriteEngine" id="RewriteEngine">RewriteEngine</a> <a name="rewriteengine" id="rewriteengine">Directive</a></h2>
 | 
						||
<table class="directive">
 | 
						||
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enables or disables runtime rewriting engine</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>RewriteEngine on|off</code></td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>RewriteEngine off</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>Extension</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_rewrite</td></tr>
 | 
						||
</table>
 | 
						||
 | 
						||
      <p>The <code class="directive">RewriteEngine</code> directive enables or
 | 
						||
      disables the runtime rewriting engine. If it is set to
 | 
						||
      <code>off</code> this module does no runtime processing at
 | 
						||
      all. It does not even update the <code>SCRIPT_URx</code>
 | 
						||
      environment variables.</p>
 | 
						||
 | 
						||
      <p>Use this directive to disable the module instead of
 | 
						||
      commenting out all the <code class="directive"><a href="#rewriterule">RewriteRule</a></code> directives!</p>
 | 
						||
 | 
						||
      <p>Note that rewrite configurations are not
 | 
						||
      inherited by virtual hosts. This means that you need to have a
 | 
						||
      <code>RewriteEngine on</code> directive for each virtual host
 | 
						||
      in which you wish to use rewrite rules.</p>
 | 
						||
 | 
						||
      <p><code class="directive">RewriteMap</code> directives of the type <code>prg</code>
 | 
						||
      are not started during server initialization if they're defined in a
 | 
						||
      context that does not have <code class="directive">RewriteEngine</code>  set to
 | 
						||
      <code>on</code></p>
 | 
						||
 | 
						||
</div>
 | 
						||
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
 | 
						||
<div class="directive-section"><h2><a name="RewriteLog" id="RewriteLog">RewriteLog</a> <a name="rewritelog" id="rewritelog">Directive</a></h2>
 | 
						||
<table class="directive">
 | 
						||
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Sets the name of the file used for logging rewrite engine
 | 
						||
processing</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>RewriteLog <em>file-path</em></code></td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_rewrite</td></tr>
 | 
						||
</table>
 | 
						||
      <p>The <code class="directive">RewriteLog</code> directive sets the name
 | 
						||
      of the file to which the server logs any rewriting actions it
 | 
						||
      performs. If the name does not begin with a slash
 | 
						||
      ('<code>/</code>') then it is assumed to be relative to the
 | 
						||
      <em>Server Root</em>. The directive should occur only once per
 | 
						||
      server config.</p>
 | 
						||
 | 
						||
<div class="note">    To disable the logging of
 | 
						||
          rewriting actions it is not recommended to set
 | 
						||
          <em>Filename</em> to <code>/dev/null</code>, because
 | 
						||
          although the rewriting engine does not then output to a
 | 
						||
          logfile it still creates the logfile output internally.
 | 
						||
          <strong>This will slow down the server with no advantage
 | 
						||
          to the administrator!</strong> To disable logging either
 | 
						||
          remove or comment out the <code class="directive">RewriteLog</code>
 | 
						||
          directive or use <code>RewriteLogLevel 0</code>!
 | 
						||
</div>
 | 
						||
 | 
						||
<div class="note"><h3>Security</h3>
 | 
						||
 | 
						||
See the <a href="../misc/security_tips.html">Apache Security Tips</a>
 | 
						||
document for details on how your security could be compromised if the
 | 
						||
directory where logfiles are stored is writable by anyone other than
 | 
						||
the user that starts the server.
 | 
						||
</div>
 | 
						||
 | 
						||
<div class="example"><h3>Example</h3><p><code>
 | 
						||
RewriteLog "/usr/local/var/apache/logs/rewrite.log"
 | 
						||
</code></p></div>
 | 
						||
 | 
						||
 | 
						||
</div>
 | 
						||
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
 | 
						||
<div class="directive-section"><h2><a name="RewriteLogLevel" id="RewriteLogLevel">RewriteLogLevel</a> <a name="rewriteloglevel" id="rewriteloglevel">Directive</a></h2>
 | 
						||
<table class="directive">
 | 
						||
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Sets the verbosity of the log file used by the rewrite
 | 
						||
engine</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>RewriteLogLevel <em>Level</em></code></td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>RewriteLogLevel 0</code></td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_rewrite</td></tr>
 | 
						||
</table>
 | 
						||
      <p>The <code class="directive">RewriteLogLevel</code> directive sets the
 | 
						||
      verbosity level of the rewriting logfile. The default level 0
 | 
						||
      means no logging, while 9 or more means that practically all
 | 
						||
      actions are logged.</p>
 | 
						||
 | 
						||
      <p>To disable the logging of rewriting actions simply set
 | 
						||
      <em>Level</em> to 0. This disables all rewrite action
 | 
						||
      logs.</p>
 | 
						||
 | 
						||
<div class="note"> Using a high value for
 | 
						||
          <em>Level</em> will slow down your Apache server
 | 
						||
          dramatically! Use the rewriting logfile at a
 | 
						||
          <em>Level</em> greater than 2 only for debugging!
 | 
						||
</div>
 | 
						||
 | 
						||
<div class="example"><h3>Example</h3><p><code>
 | 
						||
RewriteLogLevel 3
 | 
						||
</code></p></div>
 | 
						||
 | 
						||
 | 
						||
</div>
 | 
						||
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
 | 
						||
<div class="directive-section"><h2><a name="RewriteMap" id="RewriteMap">RewriteMap</a> <a name="rewritemap" id="rewritemap">Directive</a></h2>
 | 
						||
<table class="directive">
 | 
						||
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Defines a mapping function for key-lookup</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>RewriteMap <em>MapName</em> <em>MapType</em>:<em>MapSource</em>
 | 
						||
</code></td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_rewrite</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>The choice of different dbm types is available in
 | 
						||
Apache 2.0.41 and later</td></tr>
 | 
						||
</table>
 | 
						||
      <p>The <code class="directive">RewriteMap</code> directive defines a
 | 
						||
      <em>Rewriting Map</em> which can be used inside rule
 | 
						||
      substitution strings by the mapping-functions to
 | 
						||
      insert/substitute fields through a key lookup. The source of
 | 
						||
      this lookup can be of various types.</p>
 | 
						||
 | 
						||
      <p>The <a id="mapfunc" name="mapfunc"><em>MapName</em></a> is
 | 
						||
      the name of the map and will be used to specify a
 | 
						||
      mapping-function for the substitution strings of a rewriting
 | 
						||
      rule via one of the following constructs:</p>
 | 
						||
 | 
						||
      <p class="indent">
 | 
						||
        <strong><code>${</code> <em>MapName</em> <code>:</code>
 | 
						||
        <em>LookupKey</em> <code>}</code><br />
 | 
						||
         <code>${</code> <em>MapName</em> <code>:</code>
 | 
						||
        <em>LookupKey</em> <code>|</code> <em>DefaultValue</em>
 | 
						||
        <code>}</code></strong>
 | 
						||
      </p>
 | 
						||
 | 
						||
      <p>When such a construct occurs, the map <em>MapName</em> is
 | 
						||
      consulted and the key <em>LookupKey</em> is looked-up. If the
 | 
						||
      key is found, the map-function construct is substituted by
 | 
						||
      <em>SubstValue</em>. If the key is not found then it is
 | 
						||
      substituted by <em>DefaultValue</em> or by the empty string
 | 
						||
      if no <em>DefaultValue</em> was specified.</p>
 | 
						||
 | 
						||
      <p>For example, you might define a
 | 
						||
      <code class="directive">RewriteMap</code> as:</p>
 | 
						||
 | 
						||
      <div class="example"><p><code>
 | 
						||
      RewriteMap examplemap txt:/path/to/file/map.txt
 | 
						||
      </code></p></div>
 | 
						||
 | 
						||
      <p>You would then be able to use this map in a
 | 
						||
      <code class="directive">RewriteRule</code> as follows:</p>
 | 
						||
 | 
						||
      <div class="example"><p><code>
 | 
						||
      RewriteRule ^/ex/(.*) ${examplemap:$1}
 | 
						||
      </code></p></div>
 | 
						||
 | 
						||
      <p>The following combinations for <em>MapType</em> and
 | 
						||
      <em>MapSource</em> can be used:</p>
 | 
						||
 | 
						||
      <ul>
 | 
						||
        <li>
 | 
						||
          <strong>Standard Plain Text</strong><br />
 | 
						||
           MapType: <code>txt</code>, MapSource: Unix filesystem
 | 
						||
          path to valid regular file
 | 
						||
 | 
						||
          <p>This is the standard rewriting map feature where the
 | 
						||
          <em>MapSource</em> is a plain ASCII file containing
 | 
						||
          either blank lines, comment lines (starting with a '#'
 | 
						||
          character) or pairs like the following - one per
 | 
						||
          line.</p>
 | 
						||
 | 
						||
          <p class="indent">
 | 
						||
            <strong><em>MatchingKey</em>
 | 
						||
            <em>SubstValue</em></strong>
 | 
						||
          </p>
 | 
						||
 | 
						||
<div class="example"><h3>Example</h3><pre>
 | 
						||
##
 | 
						||
##  map.txt -- rewriting map
 | 
						||
##
 | 
						||
 | 
						||
Ralf.S.Engelschall    rse   # Bastard Operator From Hell
 | 
						||
Mr.Joe.Average        joe   # Mr. Average
 | 
						||
</pre></div>
 | 
						||
 | 
						||
<div class="example"><p><code>
 | 
						||
RewriteMap real-to-user txt:/path/to/file/map.txt
 | 
						||
</code></p></div>
 | 
						||
        </li>
 | 
						||
 | 
						||
        <li>
 | 
						||
          <strong>Randomized Plain Text</strong><br />
 | 
						||
           MapType: <code>rnd</code>, MapSource: Unix filesystem
 | 
						||
          path to valid regular file
 | 
						||
 | 
						||
          <p>This is identical to the Standard Plain Text variant
 | 
						||
          above but with a special post-processing feature: After
 | 
						||
          looking up a value it is parsed according to contained
 | 
						||
          ``<code>|</code>'' characters which have the meaning of
 | 
						||
          ``or''. In other words they indicate a set of
 | 
						||
          alternatives from which the actual returned value is
 | 
						||
          chosen randomly. For example, you might use the following map
 | 
						||
          file and directives to provide a random load balancing between
 | 
						||
          several back-end server, via a reverse-proxy. Images are sent
 | 
						||
          to one of the servers in the 'static' pool, while everything
 | 
						||
          else is sent to one of the 'dynamic' pool.</p>
 | 
						||
          <p>Example:</p>
 | 
						||
 | 
						||
<div class="example"><h3>Rewrite map file</h3><pre>
 | 
						||
##
 | 
						||
##  map.txt -- rewriting map
 | 
						||
##
 | 
						||
 | 
						||
static   www1|www2|www3|www4
 | 
						||
dynamic  www5|www6
 | 
						||
</pre></div>
 | 
						||
 | 
						||
<div class="example"><h3>Configuration directives</h3><p><code>
 | 
						||
RewriteMap servers rnd:/path/to/file/map.txt<br />
 | 
						||
<br />
 | 
						||
RewriteRule ^/(.*\.(png|gif|jpg)) http://${servers:static}/$1
 | 
						||
[NC,P,L]<br />
 | 
						||
RewriteRule ^/(.*) http://${servers:dynamic}/$1 [P,L]
 | 
						||
</code></p></div>
 | 
						||
        </li>
 | 
						||
 | 
						||
        <li>
 | 
						||
          <strong>Hash File</strong><br /> MapType:
 | 
						||
          <code>dbm[=<em>type</em>]</code>, MapSource: Unix filesystem
 | 
						||
          path to valid regular file
 | 
						||
 | 
						||
          <p>Here the source is a binary format DBM file containing
 | 
						||
          the same contents as a <em>Plain Text</em> format file, but
 | 
						||
          in a special representation which is optimized for really
 | 
						||
          fast lookups. The <em>type</em> can be sdbm, gdbm, ndbm, or
 | 
						||
          db depending on <a href="../install.html#dbm">compile-time
 | 
						||
          settings</a>.  If the <em>type</em> is omitted, the
 | 
						||
          compile-time default will be chosen.</p>
 | 
						||
 | 
						||
          <p>To create a dbm file from a source text file, use the <a href="../programs/httxt2dbm.html">httxt2dbm</a> utility.</p>
 | 
						||
 | 
						||
<div class="example"><p><code>
 | 
						||
$ httxt2dbm -i mapfile.txt -o mapfile.map
 | 
						||
</code></p></div>
 | 
						||
        </li>
 | 
						||
 | 
						||
        <li>
 | 
						||
          <strong>Internal Function</strong><br />
 | 
						||
           MapType: <code>int</code>, MapSource: Internal Apache
 | 
						||
          function
 | 
						||
 | 
						||
          <p>Here, the source is an internal Apache function.
 | 
						||
          Currently you cannot create your own, but the following
 | 
						||
          functions already exist:</p>
 | 
						||
 | 
						||
          <ul>
 | 
						||
            <li><strong>toupper</strong>:<br />
 | 
						||
             Converts the key to all upper case.</li>
 | 
						||
 | 
						||
            <li><strong>tolower</strong>:<br />
 | 
						||
             Converts the key to all lower case.</li>
 | 
						||
 | 
						||
            <li><strong>escape</strong>:<br />
 | 
						||
             Translates special characters in the key to
 | 
						||
            hex-encodings.</li>
 | 
						||
 | 
						||
            <li><strong>unescape</strong>:<br />
 | 
						||
             Translates hex-encodings in the key back to
 | 
						||
            special characters.</li>
 | 
						||
          </ul>
 | 
						||
        </li>
 | 
						||
 | 
						||
        <li>
 | 
						||
          <strong>External Rewriting Program</strong><br />
 | 
						||
           MapType: <code>prg</code>, MapSource: Unix filesystem
 | 
						||
          path to valid regular file
 | 
						||
 | 
						||
          <p>Here the source is a program, not a map file. To
 | 
						||
          create it you can use a language of your choice, but
 | 
						||
          the result has to be an executable program (either
 | 
						||
          object-code or a script with the magic cookie trick
 | 
						||
          '<code>#!/path/to/interpreter</code>' as the first
 | 
						||
          line).</p>
 | 
						||
 | 
						||
         <p>This program is started once, when the Apache server
 | 
						||
          is started, and then communicates with the rewriting engine
 | 
						||
          via its <code>stdin</code> and <code>stdout</code>
 | 
						||
          file-handles. For each map-function lookup it will
 | 
						||
          receive the key to lookup as a newline-terminated string
 | 
						||
          on <code>stdin</code>. It then has to give back the
 | 
						||
          looked-up value as a newline-terminated string on
 | 
						||
          <code>stdout</code> or the four-character string
 | 
						||
          ``<code>NULL</code>'' if it fails (<em>i.e.</em>, there
 | 
						||
          is no corresponding value for the given key).</p>
 | 
						||
 | 
						||
          <p>This feature utilizes the <code>rewrite-map</code> mutex,
 | 
						||
          which is required for reliable communication with the program.
 | 
						||
          The mutex mechanism and lock file can be configured with the
 | 
						||
          <code class="directive"><a href="../mod/core.html#mutex">Mutex</a></code> directive.</p>
 | 
						||
 | 
						||
          <p>External rewriting programs are not started if they're defined in a
 | 
						||
          context that does not have <code class="directive">RewriteEngine</code> set to
 | 
						||
          <code>on</code></p>.
 | 
						||
 | 
						||
          <p>A trivial program which will implement a 1:1 map (<em>i.e.</em>,
 | 
						||
          key == value) could be:</p>
 | 
						||
 | 
						||
<div class="example"><pre>
 | 
						||
#!/usr/bin/perl
 | 
						||
$| = 1;
 | 
						||
while (<STDIN>) {
 | 
						||
    # ...put here any transformations or lookups...
 | 
						||
    print $_;
 | 
						||
}
 | 
						||
</pre></div>
 | 
						||
 | 
						||
          <p>But be very careful:</p>
 | 
						||
 | 
						||
          <ol>
 | 
						||
            <li>``<em>Keep it simple, stupid</em>'' (KISS).
 | 
						||
            If this program hangs, it will cause Apache to hang
 | 
						||
            when trying to use the relevant rewrite rule.</li>
 | 
						||
 | 
						||
            <li>A common mistake is to use buffered I/O on
 | 
						||
            <code>stdout</code>. Avoid this, as it will cause a deadloop!
 | 
						||
            ``<code>$|=1</code>'' is used above, to prevent this.</li>
 | 
						||
          </ol>
 | 
						||
        </li>
 | 
						||
        <li>
 | 
						||
          <p><strong>SQL Query</strong><br />
 | 
						||
           MapType: <code>dbd</code> or <code>fastdbd</code>,
 | 
						||
           MapSource: An SQL SELECT statement that takes a single
 | 
						||
                      argument and returns a single value.</p>
 | 
						||
          <p>This uses <code class="module"><a href="../mod/mod_dbd.html">mod_dbd</a></code> to implement a rewritemap
 | 
						||
          by lookup in an SQL database.  There are two forms:
 | 
						||
          <code>fastdbd</code> caches database lookups internally,
 | 
						||
          <code>dbd</code> doesn't.  So <code>dbd</code> incurs a
 | 
						||
          performance penalty but responds immediately if the database
 | 
						||
          contents are updated, while <code>fastdbd</code> is more
 | 
						||
          efficient but won't re-read database contents until server
 | 
						||
          restart.</p>
 | 
						||
          <p>If a query returns more than one row, a random row from
 | 
						||
          the result set is used.</p>
 | 
						||
<div class="example"><h3>Example</h3><p><code>
 | 
						||
 | 
						||
RewriteMap myquery "fastdbd:SELECT destination FROM rewrite WHERE source = %s"
 | 
						||
</code></p></div>
 | 
						||
        </li>
 | 
						||
      </ul>
 | 
						||
      <p>The <code class="directive">RewriteMap</code> directive can occur more than
 | 
						||
      once. For each mapping-function use one
 | 
						||
      <code class="directive">RewriteMap</code> directive to declare its rewriting
 | 
						||
      mapfile. While you cannot <strong>declare</strong> a map in
 | 
						||
      per-directory context it is of course possible to
 | 
						||
      <strong>use</strong> this map in per-directory context. </p>
 | 
						||
 | 
						||
<div class="note"><h3>Note</h3> For plain text and DBM format files the
 | 
						||
looked-up keys are cached in-core until the <code>mtime</code> of the
 | 
						||
mapfile changes or the server does a restart. This way you can have
 | 
						||
map-functions in rules which are used for <strong>every</strong>
 | 
						||
request.  This is no problem, because the external lookup only happens
 | 
						||
once!
 | 
						||
</div>
 | 
						||
 | 
						||
 | 
						||
</div>
 | 
						||
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
 | 
						||
<div class="directive-section"><h2><a name="RewriteOptions" id="RewriteOptions">RewriteOptions</a> <a name="rewriteoptions" id="rewriteoptions">Directive</a></h2>
 | 
						||
<table class="directive">
 | 
						||
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Sets some special options for the rewrite engine</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>RewriteOptions <var>Options</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>Extension</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_rewrite</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td><code>MaxRedirects</code> is no longer available in version 2.1 and
 | 
						||
later</td></tr>
 | 
						||
</table>
 | 
						||
 | 
						||
      <p>The <code class="directive">RewriteOptions</code> directive sets some
 | 
						||
      special options for the current per-server or per-directory
 | 
						||
      configuration. The <em>Option</em> string can currently
 | 
						||
      only be one of the following:</p>
 | 
						||
 | 
						||
      <dl>
 | 
						||
      <dt><code>inherit</code></dt>
 | 
						||
      <dd>This forces the current configuration to inherit the
 | 
						||
      configuration of the parent. In per-virtual-server context,
 | 
						||
      this means that the maps, conditions and rules of the main
 | 
						||
      server are inherited. In per-directory context this means
 | 
						||
      that conditions and rules of the parent directory's
 | 
						||
      <code>.htaccess</code> configuration or
 | 
						||
      <code class="directive"><a href="../mod/core.html#directory"><Directory></a></code>
 | 
						||
      sections are inherited. The inherited rules are virtually copied
 | 
						||
      to the section where this directive is being used. If used in
 | 
						||
      combination with local rules, the inherited rules are copied behind
 | 
						||
      the local rules. The position of this directive - below or above
 | 
						||
      of local rules - has no influence on this behavior. If local
 | 
						||
      rules forced the rewriting to stop, the inherited rules won't
 | 
						||
      be processed.</dd>
 | 
						||
      </dl>
 | 
						||
 | 
						||
</div>
 | 
						||
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
 | 
						||
<div class="directive-section"><h2><a name="RewriteRule" id="RewriteRule">RewriteRule</a> <a name="rewriterule" id="rewriterule">Directive</a></h2>
 | 
						||
<table class="directive">
 | 
						||
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Defines rules for the rewriting engine</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>RewriteRule
 | 
						||
      <em>Pattern</em> <em>Substitution</em> [<em>flags</em>]</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>Extension</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_rewrite</td></tr>
 | 
						||
</table>
 | 
						||
      <p>The <code class="directive">RewriteRule</code> directive is the real
 | 
						||
      rewriting workhorse. The directive can occur more than once,
 | 
						||
      with each instance defining a single rewrite rule. The
 | 
						||
      order in which these rules are defined is important - this is the order
 | 
						||
      in which they will be applied at run-time.</p>
 | 
						||
 | 
						||
      <p><a id="patterns" name="patterns"><em>Pattern</em></a> is
 | 
						||
      a perl compatible <a id="regexp" name="regexp">regular
 | 
						||
      expression</a>. On the first RewriteRule it is applied to the (%-encoded)
 | 
						||
      <a href="./directive-dict.html#Syntax">URL-path</a> of the request;
 | 
						||
      subsequent patterns are applied to the output of the last matched
 | 
						||
      RewriteRule.</p>
 | 
						||
 | 
						||
<div class="note"><h3>What is matched?</h3>
 | 
						||
      <p>The <em>Pattern</em> will initially be matched against the part of the
 | 
						||
      URL after the hostname and port, and before the query string.</p>
 | 
						||
 | 
						||
      <p>When the RewriteRule appears in per-directory (htaccess) context, the 
 | 
						||
      <em>Pattern</em> is matched against what remains of the URL after removing
 | 
						||
      the prefix that lead Apache to the current rules (see the 
 | 
						||
      <code class="directive"><a href="#rewritebase">RewriteBase</a></code>).  The removed prefix
 | 
						||
      always ends with a slash, meaning the matching occurs against a string which
 | 
						||
      never has a leading slash.  A <em>Pattern</em> with <code>^/</code> never
 | 
						||
      matches in per-directory context.</p>
 | 
						||
 | 
						||
      <p>If you wish to match against the hostname, port, or query string, use a
 | 
						||
      <code class="directive"><a href="#rewritecond">RewriteCond</a></code> with the
 | 
						||
      <code>%{HTTP_HOST}</code>, <code>%{SERVER_PORT}</code>, or
 | 
						||
      <code>%{QUERY_STRING}</code> variables respectively. If you wish to 
 | 
						||
      match against the full URL-path in a per-directory (htaccess) RewriteRule, 
 | 
						||
      use the <code>%{REQUEST_URI}</code> variable.</p>
 | 
						||
 | 
						||
</div>
 | 
						||
 | 
						||
      <p>For some hints on <a class="glossarylink" href="../glossary.html#regex" title="see glossary">regular
 | 
						||
      expressions</a>, see
 | 
						||
      the <a href="../rewrite/intro.html#regex">mod_rewrite
 | 
						||
      Introduction</a>.</p>
 | 
						||
 | 
						||
      <p>In mod_rewrite, the NOT character
 | 
						||
      ('<code>!</code>') is also available as a possible pattern
 | 
						||
      prefix. This enables you to negate a pattern; to say, for instance:
 | 
						||
      ``<em>if the current URL does <strong>NOT</strong> match this
 | 
						||
      pattern</em>''. This can be used for exceptional cases, where
 | 
						||
      it is easier to match the negative pattern, or as a last
 | 
						||
      default rule.</p>
 | 
						||
 | 
						||
<div class="note"><h3>Note</h3>
 | 
						||
When using the NOT character to negate a pattern, you cannot include
 | 
						||
grouped wildcard parts in that pattern. This is because, when the
 | 
						||
pattern does NOT match (ie, the negation matches), there are no
 | 
						||
contents for the groups. Thus, if negated patterns are used, you
 | 
						||
cannot use <code>$N</code> in the substitution string!
 | 
						||
</div>
 | 
						||
 | 
						||
      <p>The <a id="rhs" name="rhs"><em>Substitution</em></a> of a
 | 
						||
      rewrite rule is the string that replaces the original URL-path that
 | 
						||
      was matched by <em>Pattern</em>.  The <em>Substitution</em> may
 | 
						||
      be a:</p>
 | 
						||
 | 
						||
      <dl>
 | 
						||
 | 
						||
        <dt>file-system path</dt>
 | 
						||
 | 
						||
        <dd>Designates the location on the file-system of the resource
 | 
						||
        to be delivered to the client.</dd>
 | 
						||
 | 
						||
        <dt>URL-path</dt>
 | 
						||
 | 
						||
        <dd>A <code class="directive"><a href="../mod/core.html#documentroot">DocumentRoot</a></code>-relative path to the
 | 
						||
        resource to be served. Note that <code class="module"><a href="../mod/mod_rewrite.html">mod_rewrite</a></code>
 | 
						||
        tries to guess whether you have specified a file-system path
 | 
						||
        or a URL-path by checking to see if the first segment of the
 | 
						||
        path exists at the root of the file-system. For example, if
 | 
						||
        you specify a <em>Substitution</em> string of
 | 
						||
        <code>/www/file.html</code>, then this will be treated as a
 | 
						||
        URL-path <em>unless</em> a directory named <code>www</code>
 | 
						||
        exists at the root or your file-system, in which case it will
 | 
						||
        be treated as a file-system path. If you wish other
 | 
						||
        URL-mapping directives (such as <code class="directive"><a href="../mod/mod_alias.html#alias">Alias</a></code>) to be applied to the
 | 
						||
        resulting URL-path, use the <code>[PT]</code> flag as
 | 
						||
        described below.</dd>
 | 
						||
 | 
						||
        <dt>Absolute URL</dt>
 | 
						||
 | 
						||
        <dd>If an absolute URL is specified,
 | 
						||
        <code class="module"><a href="../mod/mod_rewrite.html">mod_rewrite</a></code> checks to see whether the
 | 
						||
        hostname matches the current host. If it does, the scheme and
 | 
						||
        hostname are stripped out and the resulting path is treated as
 | 
						||
        a URL-path. Otherwise, an external redirect is performed for
 | 
						||
        the given URL. To force an external redirect back to the
 | 
						||
        current host, see the <code>[R]</code> flag below.</dd>
 | 
						||
 | 
						||
        <dt><code>-</code> (dash)</dt>
 | 
						||
 | 
						||
        <dd>A dash indicates that no substitution should be performed
 | 
						||
        (the existing path is passed through untouched). This is used
 | 
						||
        when a flag (see below) needs to be applied without changing
 | 
						||
        the path.</dd>
 | 
						||
 | 
						||
      </dl>
 | 
						||
 | 
						||
      <p>In addition to plain text, the <em>Substition</em> string can include</p>
 | 
						||
 | 
						||
      <ol>
 | 
						||
        <li>back-references (<code>$N</code>) to the RewriteRule
 | 
						||
        pattern</li>
 | 
						||
 | 
						||
        <li>back-references (<code>%N</code>) to the last matched
 | 
						||
        RewriteCond pattern</li>
 | 
						||
 | 
						||
        <li>server-variables as in rule condition test-strings
 | 
						||
        (<code>%{VARNAME}</code>)</li>
 | 
						||
 | 
						||
        <li><a href="#mapfunc">mapping-function</a> calls
 | 
						||
        (<code>${mapname:key|default}</code>)</li>
 | 
						||
      </ol>
 | 
						||
 | 
						||
      <p>Back-references are identifiers of the form
 | 
						||
      <code>$</code><strong>N</strong>
 | 
						||
      (<strong>N</strong>=0..9), which will be replaced
 | 
						||
      by the contents of the <strong>N</strong>th group of the
 | 
						||
      matched <em>Pattern</em>. The server-variables are the same
 | 
						||
      as for the <em>TestString</em> of a <code>RewriteCond</code>
 | 
						||
      directive. The mapping-functions come from the
 | 
						||
      <code>RewriteMap</code> directive and are explained there.
 | 
						||
      These three types of variables are expanded in the order above.</p>
 | 
						||
 | 
						||
      <p>As already mentioned, all rewrite rules are
 | 
						||
      applied to the <em>Substitution</em> (in the order in which
 | 
						||
      they are defined
 | 
						||
      in the config file). The URL is <strong>completely
 | 
						||
      replaced</strong> by the <em>Substitution</em> and the
 | 
						||
      rewriting process continues until all rules have been applied,
 | 
						||
      or it is explicitly terminated by a
 | 
						||
      <code><strong>L</strong></code> flag.</p>
 | 
						||
 | 
						||
     <div class="note"><h3>Modifying the Query String</h3>
 | 
						||
      <p>By default, the query string is passed through unchanged. You
 | 
						||
      can, however, create URLs in the substitution string containing
 | 
						||
      a query string part. Simply use a question mark inside the
 | 
						||
      substitution string to indicate that the following text should
 | 
						||
      be re-injected into the query string. When you want to erase an
 | 
						||
      existing query string, end the substitution string with just a
 | 
						||
      question mark. To combine new and old query strings, use the
 | 
						||
      <code>[QSA]</code> flag.</p>
 | 
						||
     </div>
 | 
						||
 | 
						||
      <p>Additionally you can set special <a name="rewriteflags" id="rewriteflags">actions</a> to be performed by
 | 
						||
      appending <strong><code>[</code><em>flags</em><code>]</code></strong>
 | 
						||
      as the third argument to the <code>RewriteRule</code>
 | 
						||
      directive. <em>Flags</em> is a comma-separated list, surround by square
 | 
						||
      brackets, of any of the flags in the following table. More
 | 
						||
      details, and examples, for each flag, are available in the <a href="../rewrite/flags.html">Rewrite Flags document</a>.</p>
 | 
						||
 | 
						||
    <table>
 | 
						||
    <tr><th>Flag and syntax</th>
 | 
						||
        <th>Function</th>
 | 
						||
    </tr>
 | 
						||
    <tr>
 | 
						||
        <td>B</td>
 | 
						||
        <td>Escape non-alphanumeric characters <em>before</em> applying
 | 
						||
        the transformation. <em><a href="../rewrite/flags.html#flag_b">details ...</a></em></td>
 | 
						||
    </tr>
 | 
						||
    <tr>
 | 
						||
        <td>chain|C</td>
 | 
						||
        <td>Rule is chained to the following rule. If the rule fails,
 | 
						||
        the rule(s) chained to it will be skipped. <em><a href="../rewrite/flags.html#flag_c">details ...</a></em></td>
 | 
						||
    </tr>
 | 
						||
    <tr>
 | 
						||
        <td>cookie|CO=<em>NAME</em>:<em>VAL</em></td>
 | 
						||
        <td>Sets a cookie in the client browser. Full syntax is: 
 | 
						||
        CO=<em>NAME</em>:<em>VAL</em>[:<em>domain</em>[:<em>lifetime</em>[:<em>path</em>[:<em>secure</em>[:<em>httponly</em>]]]]] <em><a href="../rewrite/flags.html#flag_co">details ...</a></em>
 | 
						||
        </td>
 | 
						||
    </tr>
 | 
						||
    <tr>
 | 
						||
        <td>discardpathinfo|DPI</td>
 | 
						||
        <td>Causes the PATH_INFO portion of the rewritten URI to be
 | 
						||
        discarded. <em><a href="../rewrite/flags.html#flag_dpi">details 
 | 
						||
        ...</a></em></td>
 | 
						||
    </tr>
 | 
						||
    <tr>
 | 
						||
        <td>env|E=<em>VAR</em>:<em>VAL</em></td>
 | 
						||
        <td>Causes an environment variable <em>VAR</em> to be set to the
 | 
						||
        value <em>VAL</em>. <em><a href="../rewrite/flags.html#flag_e">details ...</a></em></td>
 | 
						||
    </tr>
 | 
						||
    <tr>
 | 
						||
        <td>forbidden|F</td>
 | 
						||
        <td>Returns a 403 FORBIDDEN response to the client browser.
 | 
						||
        <em><a href="../rewrite/flags.html#flag_f">details ...</a></em></td>
 | 
						||
    </tr>
 | 
						||
    <tr>
 | 
						||
        <td>gone|G</td>
 | 
						||
        <td>Returns a 410 GONE response to the client browser. <em><a href="../rewrite/flags.html#flag_g">details ...</a></em></td>
 | 
						||
    </tr>
 | 
						||
    <tr>
 | 
						||
        <td>Handler|H=<em>Content-handler</em></td>
 | 
						||
        <td>Causes the resulting URI to be sent to the specified
 | 
						||
        <em>Content-handler</em> for processing. <em><a href="../rewrite/flags.html#flag_h">details ...</a></em></td>
 | 
						||
    </tr>
 | 
						||
    <tr>
 | 
						||
        <td>last|L</td>
 | 
						||
        <td>Stop the rewriting process immediately and don't apply any
 | 
						||
        more rules. Especially note caveats for per-directory and
 | 
						||
        .htaccess context. <em><a href="../rewrite/flags.html#flag_l">details ...</a></em></td>
 | 
						||
    </tr>
 | 
						||
    <tr>
 | 
						||
        <td>next|N</td>
 | 
						||
        <td>Re-run the rewriting process, starting again with the first
 | 
						||
        rule, using the result of the ruleset so far as a starting
 | 
						||
        point. <em><a href="../rewrite/flags.html#flag_n">details
 | 
						||
        ...</a></em></td>
 | 
						||
    </tr>
 | 
						||
    <tr>
 | 
						||
        <td>nocase|NC</td>
 | 
						||
        <td>Makes the pattern pattern comparison case-insensitive.
 | 
						||
        <em><a href="../rewrite/flags.html#flag_nc">details ...</a></em></td>
 | 
						||
    </tr>
 | 
						||
    <tr>
 | 
						||
        <td>noescape|NE</td>
 | 
						||
        <td>Prevent mod_rewrite from applying hexcode escaping of
 | 
						||
        special characters in the result of the rewrite. <em><a href="../rewrite/flags.html#flag_ne">details ...</a></em></td>
 | 
						||
    </tr>
 | 
						||
    <tr>
 | 
						||
        <td>nosubreq|NS</td>
 | 
						||
        <td>Causes a rule to be skipped if the current request is an
 | 
						||
        internal sub-request. <em><a href="../rewrite/flags.html#flag_ns">details ...</a></em></td>
 | 
						||
    </tr>
 | 
						||
    <tr>
 | 
						||
        <td>proxy|P</td>
 | 
						||
        <td>Force the substitution URL to be internally sent as a proxy
 | 
						||
        request. <em><a href="../rewrite/flags.html#flag_p">details
 | 
						||
        ...</a></em></td>
 | 
						||
    </tr>
 | 
						||
    <tr>
 | 
						||
        <td>passthrough|PT</td>
 | 
						||
        <td>Forces the resulting URI to be passed back to the URL
 | 
						||
        mapping engine for processing of other URI-to-filename
 | 
						||
        translators, such as <code>Alias</code> or
 | 
						||
        <code>Redirect</code>. <em><a href="../rewrite/flags.html#flag_pt">details ...</a></em></td>
 | 
						||
    </tr>
 | 
						||
    <tr>
 | 
						||
        <td>qsappend|QSA</td>
 | 
						||
        <td>Appends any query string created in the rewrite target to
 | 
						||
        any query string that was in the original request URL. <em><a href="../rewrite/flags.html#flag_qsa">details ...</a></em></td>
 | 
						||
    </tr>
 | 
						||
    <tr>
 | 
						||
        <td>qsdiscard|QSD</td>
 | 
						||
        <td>Discard any query string attached to the incoming URI.
 | 
						||
        <em><a href="../rewrite/flags.html#flag_qsd">details
 | 
						||
        ...</a></em></td>
 | 
						||
    </tr>
 | 
						||
    <tr>
 | 
						||
        <td>redirect|R[=<em>code</em>]</td>
 | 
						||
        <td>Forces an external redirect, optionally with the specified
 | 
						||
        HTTP status code. <em><a href="../rewrite/flags.html#flag_r">details ...</a></em>
 | 
						||
        </td>
 | 
						||
    </tr>
 | 
						||
    <tr>
 | 
						||
        <td>skip|S=<em>num</em></td>
 | 
						||
        <td>Tells the rewriting engine to skip the next <em>num</em>
 | 
						||
        rules if the current rule matches. <em><a href="../rewrite/flags.html#flag_s">details ...</a></em></td>
 | 
						||
    </tr>
 | 
						||
    <tr>
 | 
						||
        <td>tyle|T=<em>MIME-type</em></td>
 | 
						||
        <td>Force the <a class="glossarylink" href="../glossary.html#mime-type" title="see glossary">MIME-type</a> of the target file
 | 
						||
        to be the specified type. <em><a href="../rewrite/flags.html#flag_t">details ...</a></em></td>
 | 
						||
    </tr>
 | 
						||
    </table>
 | 
						||
 | 
						||
<div class="note"><h3>Home directory expansion</h3>
 | 
						||
<p> When the substitution string begins with a string
 | 
						||
resembling "/~user" (via explicit text or backreferences), mod_rewrite performs
 | 
						||
home directory expansion independent of the presence or configuration
 | 
						||
of <code class="module"><a href="../mod/mod_userdir.html">mod_userdir</a></code>.</p>
 | 
						||
 | 
						||
<p> This expansion does not occur when the <em>PT</em>
 | 
						||
flag is used on the <code class="directive"><a href="#rewriterule">RewriteRule</a></code>
 | 
						||
directive.</p>
 | 
						||
</div>
 | 
						||
 | 
						||
<div class="note"><h3>Per-directory Rewrites</h3>
 | 
						||
 | 
						||
<p>The rewrite engine may be used in <a href="../howto/htaccess.html">.htaccess</a> files.  To enable the
 | 
						||
rewrite engine for these files you need to set
 | 
						||
"<code>RewriteEngine On</code>" <strong>and</strong>
 | 
						||
"<code>Options FollowSymLinks</code>" must be enabled. If your
 | 
						||
administrator has disabled override of <code>FollowSymLinks</code> for
 | 
						||
a user's directory, then you cannot use the rewrite engine. This
 | 
						||
restriction is required for security reasons.</p>
 | 
						||
 | 
						||
<p>When using the rewrite engine in <code>.htaccess</code> files the
 | 
						||
per-directory prefix (which always is the same for a specific
 | 
						||
directory) is automatically <em>removed</em> for the pattern matching
 | 
						||
and automatically <em>added</em> after the substitution has been
 | 
						||
done. This feature is essential for many sorts of rewriting; without
 | 
						||
this, you would always have to match the parent directory, which is
 | 
						||
not always possible.  There is one exception: If a substitution string
 | 
						||
starts with <code>http://</code>, then the directory prefix will
 | 
						||
<strong>not</strong> be added, and an external redirect (or proxy
 | 
						||
throughput, if using flag <strong>P</strong>) is forced.  See the
 | 
						||
<code class="directive"><a href="#rewritebase">RewriteBase</a></code> directive for
 | 
						||
more information.</p>
 | 
						||
 | 
						||
<p>The rewrite engine may also be used in <code class="directive"><a href="../mod/core.html#directory"><Directory></a></code> sections with the same
 | 
						||
prefix-matching rules as would be applied to <code>.htaccess</code>
 | 
						||
files.  It is usually simpler, however, to avoid the prefix substitution
 | 
						||
complication by putting the rewrite rules in the main server or
 | 
						||
virtual host context, rather than in a <code class="directive"><a href="../mod/core.html#directory"><Directory></a></code> section.</p>
 | 
						||
 | 
						||
<p>Although rewrite rules are syntactically permitted in <code class="directive"><a href="../mod/core.html#location"><Location></a></code> and <code class="directive"><a href="../mod/core.html#files"><Files></a></code> sections, this
 | 
						||
should never be necessary and is unsupported.</p>
 | 
						||
 | 
						||
</div>
 | 
						||
 | 
						||
     <p>Here are all possible substitution combinations and their
 | 
						||
      meanings:</p>
 | 
						||
 | 
						||
      <p><strong>Inside per-server configuration
 | 
						||
      (<code>httpd.conf</code>)<br />
 | 
						||
       for request ``<code>GET
 | 
						||
      /somepath/pathinfo</code>'':</strong><br />
 | 
						||
      </p>
 | 
						||
 | 
						||
<div class="note"><pre>
 | 
						||
<strong>Given Rule</strong>                                      <strong>Resulting Substitution</strong>
 | 
						||
----------------------------------------------  ----------------------------------
 | 
						||
^/somepath(.*) otherpath$1                      invalid, not supported
 | 
						||
 | 
						||
^/somepath(.*) otherpath$1  [R]                 invalid, not supported
 | 
						||
 | 
						||
^/somepath(.*) otherpath$1  [P]                 invalid, not supported
 | 
						||
----------------------------------------------  ----------------------------------
 | 
						||
^/somepath(.*) /otherpath$1                     /otherpath/pathinfo
 | 
						||
 | 
						||
^/somepath(.*) /otherpath$1 [R]                 http://thishost/otherpath/pathinfo
 | 
						||
                                                via external redirection
 | 
						||
 | 
						||
^/somepath(.*) /otherpath$1 [P]                 doesn't make sense, not supported
 | 
						||
----------------------------------------------  ----------------------------------
 | 
						||
^/somepath(.*) http://thishost/otherpath$1      /otherpath/pathinfo
 | 
						||
 | 
						||
^/somepath(.*) http://thishost/otherpath$1 [R]  http://thishost/otherpath/pathinfo
 | 
						||
                                                via external redirection
 | 
						||
 | 
						||
^/somepath(.*) http://thishost/otherpath$1 [P]  doesn't make sense, not supported
 | 
						||
----------------------------------------------  ----------------------------------
 | 
						||
^/somepath(.*) http://otherhost/otherpath$1     http://otherhost/otherpath/pathinfo
 | 
						||
                                                via external redirection
 | 
						||
 | 
						||
^/somepath(.*) http://otherhost/otherpath$1 [R] http://otherhost/otherpath/pathinfo
 | 
						||
                                                via external redirection
 | 
						||
                                                (the [R] flag is redundant)
 | 
						||
 | 
						||
^/somepath(.*) http://otherhost/otherpath$1 [P] http://otherhost/otherpath/pathinfo
 | 
						||
                                                via internal proxy
 | 
						||
</pre></div>
 | 
						||
 | 
						||
      <p><strong>Inside per-directory configuration for
 | 
						||
      <code>/somepath</code><br />
 | 
						||
       (<code>/physical/path/to/somepath/.htacccess</code>, with
 | 
						||
      <code>RewriteBase /somepath</code>)<br />
 | 
						||
       for request ``<code>GET
 | 
						||
      /somepath/localpath/pathinfo</code>'':</strong><br />
 | 
						||
     </p>
 | 
						||
 | 
						||
<div class="note"><pre>
 | 
						||
<strong>Given Rule</strong>                                      <strong>Resulting Substitution</strong>
 | 
						||
----------------------------------------------  ----------------------------------
 | 
						||
^localpath(.*) otherpath$1                      /somepath/otherpath/pathinfo
 | 
						||
 | 
						||
^localpath(.*) otherpath$1  [R]                 http://thishost/somepath/otherpath/pathinfo
 | 
						||
                                                via external redirection
 | 
						||
 | 
						||
^localpath(.*) otherpath$1  [P]                 doesn't make sense, not supported
 | 
						||
----------------------------------------------  ----------------------------------
 | 
						||
^localpath(.*) /otherpath$1                     /otherpath/pathinfo
 | 
						||
 | 
						||
^localpath(.*) /otherpath$1 [R]                 http://thishost/otherpath/pathinfo
 | 
						||
                                                via external redirection
 | 
						||
 | 
						||
^localpath(.*) /otherpath$1 [P]                 doesn't make sense, not supported
 | 
						||
----------------------------------------------  ----------------------------------
 | 
						||
^localpath(.*) http://thishost/otherpath$1      /otherpath/pathinfo
 | 
						||
 | 
						||
^localpath(.*) http://thishost/otherpath$1 [R]  http://thishost/otherpath/pathinfo
 | 
						||
                                                via external redirection
 | 
						||
 | 
						||
^localpath(.*) http://thishost/otherpath$1 [P]  doesn't make sense, not supported
 | 
						||
----------------------------------------------  ----------------------------------
 | 
						||
^localpath(.*) http://otherhost/otherpath$1     http://otherhost/otherpath/pathinfo
 | 
						||
                                                via external redirection
 | 
						||
 | 
						||
^localpath(.*) http://otherhost/otherpath$1 [R] http://otherhost/otherpath/pathinfo
 | 
						||
                                                via external redirection
 | 
						||
                                                (the [R] flag is redundant)
 | 
						||
 | 
						||
^localpath(.*) http://otherhost/otherpath$1 [P] http://otherhost/otherpath/pathinfo
 | 
						||
                                                via internal proxy
 | 
						||
</pre></div>
 | 
						||
  
 | 
						||
</div>
 | 
						||
</div>
 | 
						||
<div class="bottomlang">
 | 
						||
<p><span>Available Languages: </span><a href="../en/mod/mod_rewrite.html" title="English"> en </a> |
 | 
						||
<a href="../fr/mod/mod_rewrite.html" hreflang="fr" rel="alternate" title="Français"> fr </a></p>
 | 
						||
</div><div id="footer">
 | 
						||
<p class="apache">Copyright 2010 The Apache Software Foundation.<br />Licensed under the <a href="http://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/directives.html">Directives</a> | <a href="../faq/">FAQ</a> | <a href="../glossary.html">Glossary</a> | <a href="../sitemap.html">Sitemap</a></p></div>
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