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Posted to cvs@httpd.apache.org by nd...@apache.org on 2009/12/12 21:28:45 UTC
svn commit: r889973 - in /httpd/httpd/trunk/docs/manual/mod:
mod_rewrite.html.en mod_rewrite.xml
Author: nd
Date: Sat Dec 12 20:28:44 2009
New Revision: 889973
URL: http://svn.apache.org/viewvc?rev=889973&view=rev
Log:
revert r832627, because it uses invalid xml structure
Modified:
httpd/httpd/trunk/docs/manual/mod/mod_rewrite.html.en
httpd/httpd/trunk/docs/manual/mod/mod_rewrite.xml
Modified: httpd/httpd/trunk/docs/manual/mod/mod_rewrite.html.en
URL: http://svn.apache.org/viewvc/httpd/httpd/trunk/docs/manual/mod/mod_rewrite.html.en?rev=889973&r1=889972&r2=889973&view=diff
==============================================================================
--- httpd/httpd/trunk/docs/manual/mod/mod_rewrite.html.en (original)
+++ httpd/httpd/trunk/docs/manual/mod/mod_rewrite.html.en Sat Dec 12 20:28:44 2009
@@ -94,11 +94,10 @@
<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
- <code>http://example.com/myapp/index.html</code> to
- <code>/home/www/example/newsite.html</code>, in a <code>.htaccess</code>
- file. This assumes that the content available at
- <code>http://example.com/</code> is on disk at
- <code>/home/www/example/</code>.</p>
+ 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
@@ -120,45 +119,47 @@
<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"><a href="#rewritecond">RewriteCond</a></code>
- directive defines a rule condition. One or more <code class="directive"><a href="#rewritecond">RewriteCond</a></code>
- conditions can precede a <code class="directive"><a href="#rewriterule">RewriteRule</a></code> directive. The following rewrite rule is then
- used only if these conditions are met, and if the URI matches the pattern
- specified in the rule.</p>
-
- <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
-<div class="section">
-<h2><a name="TestString" id="TestString">TestString</a></h2>
-
- <p><code><em>TestString</em></code> can contain plain text, any of the
- following expanded constructs, or both.</p>
+ <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>$N</code></strong>
- (1 <= N <= 9). They provide access to the grouped
- parts of the current <code>RewriteRule</code> pattern. The grouped
- parts of the pattern are those in parentheses.</li>
+ (0 <= N <= 9), which provide access to the grouped
+ parts (in parentheses) of the pattern, from the
+ <code>RewriteRule</code> which is subject to the current
+ set of <code>RewriteCond</code> conditions.
+ </li>
<li>
<strong>RewriteCond backreferences</strong>: These are
backreferences of the form <strong><code>%N</code></strong>
- (1 <= N <= 9). They provide access to the grouped
- parts of the last-matched <code>RewriteCond</code> pattern. The
- grouped parts of the pattern are those in parentheses.</li>
+ (1 <= N <= 9), which provide access to the grouped
+ parts (again, in parentheses) of the pattern, from the last matched
+ <code>RewriteCond</code> in the current set
+ of conditions.
+ </li>
<li>
<strong>RewriteMap expansions</strong>: These are
expansions of the form <strong><code>${mapname:key|default}</code></strong>.
- See the <a href="#mapfunc">RewriteMap documentation</a>
- for more details.
+ See <a href="#mapfunc">the documentation for
+ RewriteMap</a> for more details.
</li>
<li>
- <strong>Server variables</strong>: These are variables of
+ <strong>Server-Variables</strong>: These are variables of
the form
- <strong><code>%{ <em>NAME_OF_VARIABLE</em> }</code></strong>,
- where <em>NAME_OF_VARIABLE</em> is one of the server variables from
- the table below:
-
- <table>
+ <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 />
@@ -227,23 +228,34 @@
</td>
</tr>
</table>
- </li></ul>
- <div class="note"><p>The following variables are specific to
- <code class="module"><a href="../mod/mod_rewrite.html">mod_rewrite</a></code>:</p>
+
+ <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>Contains the text "true" if the request
- currently being processed is a sub-request, or
+ <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>The version of the Apache module API contained in the
- current httpd build, as defined in
- include/ap_mmn.h.</dd>
+ <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>
@@ -256,79 +268,108 @@
<dt><code>REQUEST_URI</code></dt>
<dd>The resource requested in the HTTP request
- line.</dd>
+ line. (In the example above, this would be
+ "/index.html".)</dd>
<dt><code>REQUEST_FILENAME</code></dt>
- <dd>The full local filesystem path of the file or
+ <dd>The full local filesystem path to the file or
script matching the request.</dd>
<dt><code>HTTPS</code></dt>
- <dd>Contains the text "on" if the connection is
- using SSL/TLS, or "off" otherwise. This variable
- does not depend on <code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code> being loaded.</dd>
+ <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>Note that the <code>SCRIPT_FILENAME</code> and
- <code>REQUEST_FILENAME</code>
- variables both contain the value of the
+ <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.
- If a substitution occurs and rewriting continues,
- the value of both variables will be updated accordingly.
- In a per-server context, before the
- request is mapped to the filesystem, these variables contain the value
- of <code>REQUEST_URI</code>, because the full filesystem path is not
- yet known. To obtain the full filesystem
- path of a request in a per-server context, use a URL-based
+ <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 <code>REQUEST_FILENAME</code>.</p>
+ the final value of REQUEST_FILENAME.</p></li>
- <p>Other available variables include the following:</p>
- <ul><li>
- <code>%{ENV:<em>variable</em>}</code>, where <em>variable</em> can be
- any environment variable.</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:<em>variable</em>}</code>, where <em>variable</em> is the
+ <code>%{SSL:variable}</code>, where <em>variable</em> is the
name of an <a href="mod_ssl.html#envvars">SSL environment
- variable</a>. If <code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code> is not loaded, this
- will always expand to the empty string.</li>
+ 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:<em>header</em>}</code>, where <em>header</em> can be
- any HTTP MIME-header name. For example,
- <code>%{HTTP:Proxy-Connection}</code> is the value of the HTTP header
- ``<code>Proxy-Connection:</code>''. If a HTTP header is used in a
- condition, and the condition evaluates to <code>true</code>, then that
- header is added to the Vary header of the response. This is used to
- ensure proper caching.
- If a previous condition has evaluated to <code>true</code> and the
- '<strong><code>ornext|OR</code></strong>' flag is in use, later
- conditions are not evaluated, and therefore headers are not added to the
- Vary header.</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:<em>variable</em>}</code>, which is used to perform
- an internal URL-based sub-request, to determine the final
- value of <em>variable</em>. This can be used to access the value of
- a variable which is to be set in a later phase. For example, the
- <code>REMOTE_USER</code> variable is set in the authorization phase of
- processing. This comes after the URL translation phase, where rewrite
- rules in <code>httpd.conf</code> are applied, but before the fixup
- phase, where rewrite rules in a <code>.htaccess</code> file are applied.
- Therefore, to obtain the value of the <code>REMOTE_USER</code> variable
- within <code>httpd.conf</code>, you must use <code>%{LA-U:REMOTE_USER}</code>. To obtain the value of the
- <code>REMOTE_USER</code> variable within a <code>.htaccess</code> file,
- simply use <code>%{REMOTE_USER}</code></li>
- </ul>
- </div>
+ <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>
- <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
-<div class="section">
-<h2><a name="CondPattern" id="CondPattern">CondPattern</a></h2>
-
<p><em>CondPattern</em> is the condition pattern,
a regular expression which is applied to the
current instance of the <em>TestString</em>.
@@ -500,7 +541,6 @@
or your browser identifies itself as something non-standard), you get
the std (standard) homepage.</p>
-</div>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
Modified: httpd/httpd/trunk/docs/manual/mod/mod_rewrite.xml
URL: http://svn.apache.org/viewvc/httpd/httpd/trunk/docs/manual/mod/mod_rewrite.xml?rev=889973&r1=889972&r2=889973&view=diff
==============================================================================
--- httpd/httpd/trunk/docs/manual/mod/mod_rewrite.xml (original)
+++ httpd/httpd/trunk/docs/manual/mod/mod_rewrite.xml Sat Dec 12 20:28:44 2009
@@ -500,11 +500,10 @@
module="mod_rewrite">RewriteRule</directive> directives.</p>
<p>The example below demonstrates how to map
- <code>http://example.com/myapp/index.html</code> to
- <code>/home/www/example/newsite.html</code>, in a <code>.htaccess</code>
- file. This assumes that the content available at
- <code>http://example.com/</code> is on disk at
- <code>/home/www/example/</code>.</p>
+ 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>
<example>
<pre>
RewriteEngine On
@@ -529,46 +528,49 @@
<override>FileInfo</override>
<usage>
- <p>The <directive module="mod_rewrite">RewriteCond</directive>
- directive defines a rule condition. One or more <directive
- module="mod_rewrite">RewriteCond</directive>
- conditions can precede a <directive module="mod_rewrite"
- >RewriteRule</directive> directive. The following rewrite rule is then
- used only if these conditions are met, and if the URI matches the pattern
- specified in the rule.</p>
-
- <section id="TestString">
- <title>TestString</title>
- <p><code><em>TestString</em></code> can contain plain text, any of the
- following expanded constructs, or both.</p>
+ <p>The <directive>RewriteCond</directive> directive defines a
+ rule condition. One or more <directive>RewriteCond</directive>
+ can precede a <directive module="mod_rewrite">RewriteRule</directive>
+ 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>$N</code></strong>
- (1 <= N <= 9). They provide access to the grouped
- parts of the current <code>RewriteRule</code> pattern. The grouped
- parts of the pattern are those in parentheses.</li>
+ (0 <= N <= 9), which provide access to the grouped
+ parts (in parentheses) of the pattern, from the
+ <code>RewriteRule</code> which is subject to the current
+ set of <code>RewriteCond</code> conditions.
+ </li>
<li>
<strong>RewriteCond backreferences</strong>: These are
backreferences of the form <strong><code>%N</code></strong>
- (1 <= N <= 9). They provide access to the grouped
- parts of the last-matched <code>RewriteCond</code> pattern. The
- grouped parts of the pattern are those in parentheses.</li>
+ (1 <= N <= 9), which provide access to the grouped
+ parts (again, in parentheses) of the pattern, from the last matched
+ <code>RewriteCond</code> in the current set
+ of conditions.
+ </li>
<li>
<strong>RewriteMap expansions</strong>: These are
expansions of the form <strong><code
>${mapname:key|default}</code></strong>.
- See the <a href="#mapfunc">RewriteMap documentation</a>
- for more details.
+ See <a href="#mapfunc">the documentation for
+ RewriteMap</a> for more details.
</li>
<li>
- <strong>Server variables</strong>: These are variables of
+ <strong>Server-Variables</strong>: These are variables of
the form
- <strong><code>%{ <em>NAME_OF_VARIABLE</em> }</code></strong>,
- where <em>NAME_OF_VARIABLE</em> is one of the server variables from
- the table below:
-
- <table>
+ <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>
<columnspec><column width=".3"/><column width=".3"/>
<column width=".3"/></columnspec>
<tr>
@@ -638,23 +640,34 @@
</td>
</tr>
</table>
- </li></ul>
- <note><p>The following variables are specific to
- <module>mod_rewrite</module>:</p>
+
+ <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>
+ <note>
<dl>
<dt><code>IS_SUBREQ</code></dt>
- <dd>Contains the text "true" if the request
- currently being processed is a sub-request, or
+ <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>The version of the Apache module API contained in the
- current httpd build, as defined in
- include/ap_mmn.h.</dd>
+ <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>
@@ -667,78 +680,108 @@
<dt><code>REQUEST_URI</code></dt>
<dd>The resource requested in the HTTP request
- line.</dd>
+ line. (In the example above, this would be
+ "/index.html".)</dd>
<dt><code>REQUEST_FILENAME</code></dt>
- <dd>The full local filesystem path of the file or
+ <dd>The full local filesystem path to the file or
script matching the request.</dd>
<dt><code>HTTPS</code></dt>
- <dd>Contains the text "on" if the connection is
- using SSL/TLS, or "off" otherwise. This variable
- does not depend on <module>mod_ssl</module> being loaded.</dd>
+ <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
+ <module>mod_ssl</module> is loaded).</dd>
</dl>
</note>
+ </li>
+ </ul>
+
+ <p>Other things you should be aware of:</p>
- <p>Note that the <code>SCRIPT_FILENAME</code> and
- <code>REQUEST_FILENAME</code>
- variables both contain the value of the
+ <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.
- If a substitution occurs and rewriting continues,
- the value of both variables will be updated accordingly.
- In a per-server context, before the
- request is mapped to the filesystem, these variables contain the value
- of <code>REQUEST_URI</code>, because the full filesystem path is not
- yet known. To obtain the full filesystem
- path of a request in a per-server context, use a URL-based
+ <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 <code>REQUEST_FILENAME</code>.</p>
+ the final value of REQUEST_FILENAME.</p></li>
- <p>Other available variables include the following:</p>
- <ul><li>
- <code>%{ENV:<em>variable</em>}</code>, where <em>variable</em> can be
- any environment variable.</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:<em>variable</em>}</code>, where <em>variable</em> is the
+ <code>%{SSL:variable}</code>, where <em>variable</em> is the
name of an <a href="mod_ssl.html#envvars">SSL environment
- variable</a>. If <module>mod_ssl</module> is not loaded, this
- will always expand to the empty string.</li>
+ variable</a>, can be used whether or not
+ <module>mod_ssl</module> 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:<em>header</em>}</code>, where <em>header</em> can be
- any HTTP MIME-header name. For example,
- <code>%{HTTP:Proxy-Connection}</code> is the value of the HTTP header
- ``<code>Proxy-Connection:</code>''. If a HTTP header is used in a
- condition, and the condition evaluates to <code>true</code>, then that
- header is added to the Vary header of the response. This is used to
- ensure proper caching.
- If a previous condition has evaluated to <code>true</code> and the
- '<strong><code>ornext|OR</code></strong>' flag is in use, later
- conditions are not evaluated, and therefore headers are not added to the
- Vary header.</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:<em>variable</em>}</code>, which is used to perform
- an internal URL-based sub-request, to determine the final
- value of <em>variable</em>. This can be used to access the value of
- a variable which is to be set in a later phase. For example, the
- <code>REMOTE_USER</code> variable is set in the authorization phase of
- processing. This comes after the URL translation phase, where rewrite
- rules in <code>httpd.conf</code> are applied, but before the fixup
- phase, where rewrite rules in a <code>.htaccess</code> file are applied.
- Therefore, to obtain the value of the <code>REMOTE_USER</code> variable
- within <code>httpd.conf</code>, you must use <code
- >%{LA-U:REMOTE_USER}</code>. To obtain the value of the
- <code>REMOTE_USER</code> variable within a <code>.htaccess</code> file,
- simply use <code>%{REMOTE_USER}</code></li>
- </ul>
- </section>
+ <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>
- <section id="CondPattern">
- <title>CondPattern</title>
<p><em>CondPattern</em> is the condition pattern,
a regular expression which is applied to the
current instance of the <em>TestString</em>.
@@ -914,7 +957,6 @@
or your browser identifies itself as something non-standard), you get
the std (standard) homepage.</p>
-</section>
</usage>
</directivesynopsis>