>
<!--#include virtual="header.html" -->
-<h1 ALIGN="CENTER">Module mod_rewrite (Version 3.0)</h1>
+<h1 ALIGN="CENTER">Module mod_rewrite</h1>
This module is contained in the <code>mod_rewrite.c</code> file, with Apache
1.2 and later. It provides a rule-based rewriting engine to rewrite requested
substitution.
<p>
-It operates on the full URLs (including the PATH_INFO part) both in
-per-server context (httpd.conf) and per-dir context (.htaccess) and even
-can generate QUERY_STRING parts on result. The rewritten result can lead to internal sub-processing, external request redirection or to internal proxy throughput.
+It operates on the full URLs (including the PATH_INFO part) both in per-server
+context (httpd.conf) and per-dir context (.htaccess) and even can generate
+QUERY_STRING parts on result. The rewritten result can lead to internal
+sub-processing, external request redirection or to internal proxy throughput.
<p>
-The latest version can be found on<br>
-<a href="http://www.engelschall.com/sw/mod_rewrite/">
-<code><b>http://www.engelschall.com/sw/mod_rewrite/</b></code></a>
-
-<p>
-Copyright © 1996,1997 <b>The Apache Group</b>, All rights reserved.<br>
-Copyright © 1996,1997 <i>Ralf S. Engelschall</i>, All rights reserved.
+This module was originally written in April 1996 and
+gifted exclusively to the The Apache Group in July 1997 by
<p>
-Written for <b>The Apache Group</b> by
<blockquote>
<i>Ralf S. Engelschall</i><br>
<a href="mailto:rse@engelschall.com"><tt>rse@engelschall.com</tt></a><br>
conditions and rules of the main server gets inherited. In per-directory
context this means that conditions and rules of the parent directory's
<tt>.htaccess</tt> configuration gets inherited.
-<p>
</ul>
<p>
config.
<p>
-<table width="70%" border=2 bgcolor="#c0c0e0" cellspacing=0 cellpadding=10>
+<table width="70%" border=0 bgcolor="#f0f0f0" cellspacing=0 cellpadding=10>
<tr><td>
To disable the logging of rewriting actions it is not recommended
to set <em>Filename</em>
</table>
<p>
-<table width="70%" border=2 bgcolor="#c0c0e0" cellspacing=0 cellpadding=10>
+<table width="70%" border=0 bgcolor="#fff0f0" cellspacing=0 cellpadding=10>
<tr><td>
SECURITY: See the <a
href="../misc/security_tips.html">Apache Security
This disables all rewrite action logs.
<p>
-<table width="70%" border=2 bgcolor="#c0c0e0" cellspacing=0 cellpadding=10>
+<table width="70%" border=0 bgcolor="#f0f0f0" cellspacing=0 cellpadding=10>
<tr><td>
<b>Notice:</b> Using a high value for <i>Level</i> will slow down your Apache
server dramatically! Use the rewriting logfile only for debugging or at least
string as in the following example:
<p>
-<table border=2 cellspacing=1 cellpadding=5 bgcolor="#d0d0d0">
+<table border=0 cellspacing=1 cellpadding=5 bgcolor="#f0f0f0">
<tr><td><pre>
#
# map.real-to-user -- maps realnames to usernames
</table>
<p>
-<table border=2 cellspacing=1 cellpadding=5 bgcolor="#d0d0d0">
+<table border=0 cellspacing=1 cellpadding=5 bgcolor="#f0f0f0">
<tr><td><pre>
RewriteMap real-to-host txt:/path/to/file/map.real-to-user
</pre></td></tr>
for the given key). A trivial program which will implement a 1:1 map
(i.e. key == value) could be:
<p>
-<table border=2 cellspacing=1 cellpadding=5 bgcolor="#d0d0d0">
+<table border=0 cellspacing=1 cellpadding=5 bgcolor="#f0f0f0">
<tr><td><pre>
#!/usr/bin/perl
$| = 1;
context.
<p>
-<table width="70%" border=2 bgcolor="#c0c0e0" cellspacing=0 cellpadding=10>
+<table width="70%" border=0 bgcolor="#f0f0f0" cellspacing=0 cellpadding=10>
<tr><td>
For plain text and DBM format files the looked-up keys are cached in-core
until the <tt>mtime</tt> of the mapfile changes or the server does a
directive to specify the correct URL-prefix.
<p>
-<table width="70%" border=2 bgcolor="#c0c0e0" cellspacing=0 cellpadding=10>
+<table width="70%" border=0 bgcolor="#fff0f0" cellspacing=0 cellpadding=10>
<tr><td>
So, if your webserver's URLs are <b>not</b> directly
related to physical file paths, you have to use <tt>RewriteBase</tt> in every
Assume the following per-directory config file:
<p>
-<table border=2 cellspacing=1 cellpadding=5 bgcolor="#d0d0d0">
+<table border=0 cellspacing=1 cellpadding=5 bgcolor="#f0f0f0">
<tr><td><pre>
#
# /abc/def/.htaccess -- per-dir config file for directory /abc/def
rewritten to the physical file <tt>/abc/def/newstuff.html</tt>.
<p>
-<table width="70%" border=2 bgcolor="#c0c0e0" cellspacing=0 cellpadding=10>
+<table width="70%" border=0 bgcolor="#fff0f0" cellspacing=0 cellpadding=10>
<tr><td>
<font size=-1>
<b>For the Apache hackers:</b><br>
of the following list:
<p>
-<table bgcolor="#d0d0d0" cellspacing=0 cellpadding=5>
+<table bgcolor="#f0f0f0" cellspacing=0 cellpadding=5>
<tr>
<td valign=top>
<b>HTTP headers:</b><p>
TIME_MIN<br>
TIME_SEC<br>
TIME_WDAY<br>
+TIME<br>
</font>
</td>
<p>
-<table width="70%" border=2 bgcolor="#c0c0e0" cellspacing=0 cellpadding=10>
+<table width="70%" border=0 bgcolor="#f0f0f0" cellspacing=0 cellpadding=10>
<tr><td>
These variables all correspond to the similar named HTTP MIME-headers, C
variables of the Apache server or <tt>struct tm</tt> fields of the Unix
regular expression strings you can also use one of the following:
<p>
<ul>
+<li>'<b><CondPattern</b>' (is lexicographically lower)<br>
+Treats the <i>CondPattern</i> as a plain string and compares it
+lexicographically to <i>TestString</i> and results in a true expression if
+<i>TestString</i> is lexicographically lower then <i>CondPattern</i>.
+<p>
+<li>'<b>>CondPattern</b>' (is lexicographically greater)<br>
+Treats the <i>CondPattern</i> as a plain string and compares it
+lexicographically to <i>TestString</i> and results in a true expression if
+<i>TestString</i> is lexicographically greater then <i>CondPattern</i>.
+<p>
+<li>'<b>=CondPattern</b>' (is lexicographically equal)<br>
+Treats the <i>CondPattern</i> as a plain string and compares it
+lexicographically to <i>TestString</i> and results in a true expression if
+<i>TestString</i> is lexicographically equal to <i>CondPattern</i>, i.e the
+two strings are exactly equal (character by character).
+<p>
<li>'<b>-d</b>' (is <b>d</b>irectory)<br>
Treats the <i>TestString</i> as a pathname and
tests if it exists and is a directory.
RewriteRule ...some special stuff for any of these hosts...
</pre></blockquote>
Without this flag you had to write down the cond/rule three times.
-<p>
</ul>
<p>
get the min homepage, which contains no images, no tables, etc. If you
use any other browser you get the standard homepage.
</blockquote>
-<p>
<p>
<hr noshade size=1>
Some hints about the syntax of regular expressions:
<p>
-<table bgcolor="#d0d0d0" cellspacing=0 cellpadding=5>
+<table bgcolor="#f0f0f0" cellspacing=0 cellpadding=5>
<tr>
<td valign=top>
<pre>
last default rule.
<p>
-<table width="70%" border=2 bgcolor="#c0c0e0" cellspacing=0 cellpadding=10>
+<table width="70%" border=0 bgcolor="#fff0f0" cellspacing=0 cellpadding=10>
<tr><td>
<b>Notice!</b> When using the NOT character to negate a pattern you cannot
have grouped wildcard parts in the pattern. This is impossible because when
pattern to be applied before a substitution occurs.
<p>
-<table width="70%" border=2 bgcolor="#c0c0e0" cellspacing=0 cellpadding=10>
+One more note: You can even create URLs in the substitution string containing
+a query string part. Just use a question mark inside the substitution string
+to indicate that the following stuff should be re-injected into the
+QUERY_STRING. When you want to erase an existing query string, end the
+substitution string with just the question mark.
+
+<p>
+<table width="70%" border=0 bgcolor="#fff0f0" cellspacing=0 cellpadding=10>
<tr><td>
<b>Notice</b>: There is a special feature. When you prefix a substitution
field with <tt>http://</tt><em>thishost</em>[<em>:thisport</em>] then
chance is high that you will run into problems (or even overhead) on sub-requests.
In these cases, use this flag.
<p>
+<li>'<strong><code>qsappend|QSA</code></strong>' (<b>q</b>uery <b>s</b>tring
+ <b>a</b>ppend)<br>
+ This flag forces the rewriting engine to append a query
+ string part in the substitution string to the existing one instead of
+ replacing it. Use this when you want to add more data to the query string
+ via a rewrite rule.
+<p>
<li>'<strong><code>passthrough|PT</code></strong>' (<b>p</b>ass <b>t</b>hrough to next handler)<br>
This flag forces the rewriting engine to set the <code>uri</code> field
of the internal <code>request_rec</code> structure to the value
typical example is the use of <tt>mod_alias</tt> and
<tt>mod_rewrite</tt>..
<p>
-<table width="70%" border=2 bgcolor="#c0c0e0" cellspacing=0 cellpadding=10>
+<table width="70%" border=0 bgcolor="#fff0f0" cellspacing=0 cellpadding=10>
<tr><td>
<font size=-1>
<b>For the Apache hackers:</b><br>
</ul>
<p>
-<table width="70%" border=2 bgcolor="#c0c0e0" cellspacing=0 cellpadding=10>
+<table width="70%" border=0 bgcolor="#fff0f0" cellspacing=0 cellpadding=10>
<tr><td>
Remember: Never forget that <em>Pattern</em> gets applied to a complete URL
in per-server configuration files. <b>But in per-directory configuration
</table>
<p>
-<table width="70%" border=2 bgcolor="#c0c0e0" cellspacing=0 cellpadding=10>
+<table width="70%" border=0 bgcolor="#fff0f0" cellspacing=0 cellpadding=10>
<tr><td>
Notice! To enable the rewriting engine for per-directory configuration files
you need to set ``<tt>RewriteEngine On</tt>'' in these files <b>and</b>
for request ``<tt>GET /somepath/pathinfo</tt>'':</b><br>
<p>
-<table bgcolor="#d0d0d0" cellspacing=0 cellpadding=5>
+<table bgcolor="#f0f0f0" cellspacing=0 cellpadding=5>
<tr>
<td>
<pre>
request ``<tt>GET /somepath/localpath/pathinfo</tt>'':</b><br>
<p>
-<table bgcolor="#d0d0d0" cellspacing=0 cellpadding=5>
+<table bgcolor="#f0f0f0" cellspacing=0 cellpadding=5>
<tr>
<td>
<pre>
</blockquote>
+<!--%hypertext -->
+<hr>
+<!--/%hypertext -->
+
+<center>
+<a name="Additional">
+<h1>Additional Features</h1>
+</a>
+</center>
+
+<a name="EnvVar">
+<h2>Environment Variables</h2>
+</a>
+
+This module keeps track of two additional (non-standard) CGI/SSI environment
+variables named <tt>SCRIPT_URL</tt> and <tt>SCRIPT_URI</tt>. These contain
+the <em>logical</em> Web-view to the current resource, while the standard CGI/SSI
+variables <tt>SCRIPT_NAME</tt> and <tt>SCRIPT_FILENAME</tt> contain the
+<em>physical</em> System-view.
+
+<p>
+Notice: These variables hold the URI/URL <em>as they were initially
+requested</em>, i.e. in a state <em>before</em> any rewriting. This is
+important because the rewriting process is primarily used to rewrite logical
+URLs to physical pathnames.
+
+<p>
+<b>Example:</b>
+
+<blockquote>
+<pre>
+SCRIPT_NAME=/v/sw/free/lib/apache/global/u/rse/.www/index.html
+SCRIPT_FILENAME=/u/rse/.www/index.html
+SCRIPT_URL=/u/rse/
+SCRIPT_URI=http://en2.en.sdm.de/u/rse/
+</pre>
+</blockquote>
+
+
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