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From noi...@apache.org
Subject svn commit: r371886 - /httpd/httpd/branches/2.2.x/docs/manual/mod/mod_rewrite.xml
Date Tue, 24 Jan 2006 10:39:26 GMT
Author: noirin
Date: Tue Jan 24 02:39:23 2006
New Revision: 371886

URL: http://svn.apache.org/viewcvs?rev=371886&view=rev
Log:
Backport of mod_rewrite reference manual fixes

Modified:
    httpd/httpd/branches/2.2.x/docs/manual/mod/mod_rewrite.xml

Modified: httpd/httpd/branches/2.2.x/docs/manual/mod/mod_rewrite.xml
URL: http://svn.apache.org/viewcvs/httpd/httpd/branches/2.2.x/docs/manual/mod/mod_rewrite.xml?rev=371886&r1=371885&r2=371886&view=diff
==============================================================================
--- httpd/httpd/branches/2.2.x/docs/manual/mod/mod_rewrite.xml (original)
+++ httpd/httpd/branches/2.2.x/docs/manual/mod/mod_rewrite.xml Tue Jan 24 02:39:23 2006
@@ -36,18 +36,18 @@
       <p>This module uses a rule-based rewriting engine (based on a
       regular-expression parser) to rewrite requested URLs on the
       fly. It supports an unlimited number of rules and an
-      unlimited number of attached rule conditions for each rule to
+      unlimited number of attached rule conditions for each rule, to
       provide a really flexible and powerful URL manipulation
       mechanism. The URL manipulations can depend on various tests,
-      for instance server variables, environment variables, HTTP
-      headers, time stamps and even external database lookups in
-      various formats can be used to achieve a really granular URL
+      of server variables, environment variables, HTTP
+      headers, or time stamps. Even external database lookups in
+      various formats can be used to achieve highly granular URL
       matching.</p>
 
       <p>This module operates on the full URLs (including the
       path-info part) both in per-server context
       (<code>httpd.conf</code>) and per-directory context
-      (<code>.htaccess</code>) and can even generate query-string
+      (<code>.htaccess</code>) and can generate query-string
       parts on result. The rewritten result can lead to internal
       sub-processing, external request redirection or even to an
       internal proxy throughput.</p>
@@ -79,8 +79,8 @@
       System-view. </p>
 
       <p>Notice: These variables hold the URI/URL <em>as they were
-      initially requested</em>, <em>i.e.</em>, <em>before</em> any
-      rewriting. This is important because the rewriting process is
+      initially requested</em>, that is, <em>before</em> any
+      rewriting. This is important to note because the rewriting process is
       primarily used to rewrite logical URLs to physical
       pathnames.</p>
 
@@ -147,12 +147,13 @@
 
       <p>The <directive>RewriteOptions</directive> directive sets some
       special options for the current per-server or per-directory
-      configuration. The <em>Option</em> string can be currently only one:</p>
+      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
+      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
@@ -192,7 +193,7 @@
 <note type="securitywarning"><title>Security</title>
 
 See the <a href="../misc/security_tips.html">Apache Security Tips</a>
-document for details on why your security could be compromised if the
+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.
 </note>
@@ -288,7 +289,7 @@
         <code>}</code></strong>
       </p>
 
-      <p>When such a construct occurs the map <em>MapName</em> is
+      <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
@@ -435,23 +436,23 @@
            MapType: <code>int</code>, MapSource: Internal Apache
           function 
 
-          <p>Here the source is an internal Apache function.
+          <p>Here, the source is an internal Apache function.
           Currently you cannot create your own, but the following
-          functions already exists:</p>
+          functions already exist:</p>
 
           <ul>
             <li><strong>toupper</strong>:<br />
-             Converts the looked up key to all upper case.</li>
+             Converts the key to all upper case.</li>
 
             <li><strong>tolower</strong>:<br />
-             Converts the looked up key to all lower case.</li>
+             Converts the key to all lower case.</li>
 
             <li><strong>escape</strong>:<br />
-             Translates special characters in the looked up key to
+             Translates special characters in the key to
             hex-encodings.</li>
 
             <li><strong>unescape</strong>:<br />
-             Translates hex-encodings in the looked up key back to
+             Translates hex-encodings in the key back to
             special characters.</li>
           </ul>
         </li>
@@ -462,15 +463,15 @@
           path to valid regular file 
 
           <p>Here the source is a program, not a map file. To
-          create it you can use the language of your choice, but
-          the result has to be a executable (<em>i.e.</em>, either
+          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 at startup of the Apache
-          servers and then communicates with the rewriting engine
-          over its <code>stdin</code> and <code>stdout</code>
+         <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
@@ -495,18 +496,18 @@
           <p>But be very careful:</p>
 
           <ol>
-            <li>``<em>Keep it simple, stupid</em>'' (KISS), because
-            if this program hangs it will hang the Apache server
-            when the rule occurs.</li>
-
-            <li>Avoid one common mistake: never do buffered I/O on
-            <code>stdout</code>! This will cause a deadloop! Hence
-            the ``<code>$|=1</code>'' in the above example...</li>
-
-            <li>Use the <directive
-            module="mod_rewrite">RewriteLock</directive> directive to
-            define a lockfile mod_rewrite can use to synchronize the
-            communication to the program. By default no such
+            <li>``<em>Keep it simple, stupid</em>'' (KISS).
+	    If this program hangs, it will cause Apache to hang 
+	    when trying to use the relevant rewrite rule.</li>
+
+            <li>A common mistake is to use buffered I/O on
+            <code>stdout</code>. Avoid this, as it will cause a deadloop!
+            ``<code>$|=1</code>'' is used above, to prevent this.</li>
+
+            <li>The <directive
+	    module="mod_rewrite">RewriteLock</directive> directive can 
+	    be used to define a lockfile which mod_rewrite can use to synchronize 
+            communication with the mapping program. By default no such
             synchronization takes place.</li>
           </ol>
         </li>
@@ -543,26 +544,26 @@
       sets the base URL for per-directory rewrites. As you will see
       below, <directive module="mod_rewrite">RewriteRule</directive>
       can be used in per-directory config files
-      (<code>.htaccess</code>). There it will act locally,
-      <em>i.e.</em>, the local directory prefix is stripped at this
-      stage of processing and your rewriting rules act only on the
-      remainder. At the end it is automatically added back to the
+      (<code>.htaccess</code>). In such a case, it will act locally,
+      stripping the local directory prefix before processing, and applying
+      rewrite rules only to the remainder. When processing is complete, the 
+      prefix is automatically added back to the
       path. The default setting is; <directive>RewriteBase</directive> <em>physical-directory-path</em></p>
 
       <p>When a substitution occurs for a new URL, this module has
       to re-inject the URL into the server processing. To be able
       to do this it needs to know what the corresponding URL-prefix
       or URL-base is. By default this prefix is the corresponding
-      filepath itself. <strong>But at most websites URLs are NOT
+      filepath itself. <strong>However, for most websites, URLs are NOT
       directly related to physical filename paths, so this
-      assumption will usually be wrong!</strong> There you have to
+      assumption will often be wrong!</strong> Therefore, you can 
       use the <code>RewriteBase</code> directive to specify the
       correct URL-prefix.</p>
 
 <note> If your webserver's URLs are <strong>not</strong> directly
-related to physical file paths, you have to use
+related to physical file paths, you will need to use
 <directive>RewriteBase</directive> in every <code>.htaccess</code>
-files where you want to use <directive
+file where you want to use <directive
 module="mod_rewrite">RewriteRule</directive> directives.
 </note>
 
@@ -607,17 +608,15 @@
 Result:
   /abc/def/newstuff.html
 </pre>
-              <p>This seems very complicated but is
-              the correct Apache internal processing, because the
-              per-directory rewriting comes too late in the
-              process. So, when it occurs the (rewritten) request
-              has to be re-injected into the Apache kernel! BUT:
-              While this seems like a serious overhead, it really
-              isn't, because this re-injection happens fully
-              internally to the Apache server and the same
-              procedure is used by many other operations inside
-              Apache. So, you can be sure the design and
-              implementation is correct.</p>
+              <p>This seems very complicated, but is in fact
+              correct Apache internal processing. Because the
+              per-directory rewriting comes late in the
+              process, the rewritten request
+              has to be re-injected into the Apache kernel. 
+              This is not the serious overhead it may seem to be - 
+              this re-injection is completely internal to the 
+	      Apache server (and the same procedure is used by 
+	      many other operations within Apache).</p> 
 </note>
 
 </usage>
@@ -636,63 +635,44 @@
 
 <usage>
       <p>The <directive>RewriteCond</directive> directive defines a
-      rule condition. Precede a <directive
-      module="mod_rewrite">RewriteRule</directive> directive with one
-      or more <directive>RewriteCond</directive> directives. The following
-      rewriting rule is only used if its pattern matches the current
-      state of the URI <strong>and</strong> if these additional
-      conditions apply too.</p>
+      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 contains the
+      <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 
-
-          <p class="indent">
-            <strong><code>$N</code></strong>
-          </p>
-          (0 &lt;= N &lt;= 9) which provide access to the grouped
-          parts (parenthesis!) of the pattern from the
-          corresponding <code>RewriteRule</code> directive (the one
-          following the current bunch of <code>RewriteCond</code>
-          directives).
+          backreferences of the form <strong><code>$N</code></strong>
+          (0 &lt;= N &lt;= 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 
-
-          <p class="indent">
-            <strong><code>%N</code></strong>
-          </p>
-          (1 &lt;= N &lt;= 9) which provide access to the grouped
-          parts (parentheses!) of the pattern from the last matched
-          <code>RewriteCond</code> directive in the current bunch
+          backreferences of the form <strong><code>%N</code></strong>
+          (1 &lt;= N &lt;= 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 
-
-          <p class="indent">
-            <strong><code>${mapname:key|default}</code></strong>
-          </p>
+          expansions of the form <strong><code
+	  >${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 
-
-          <p class="indent">
             <strong><code>%{</code> <em>NAME_OF_VARIABLE</em>
             <code>}</code></strong>
-          </p>
           where <em>NAME_OF_VARIABLE</em> can be a string taken
           from the following list: 
 
@@ -767,15 +747,14 @@
             </tr>
           </table>
 
-<note>
                 <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:</p>
-
+                mod_rewrite include those below.</p>
+	<note>
                 <dl>
                   <dt><code>IS_SUBREQ</code></dt>
 
@@ -819,7 +798,7 @@
 
                   <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
+                  can be safely used regardless of whether or not
                   <module>mod_ssl</module> is loaded).</dd>
 
                 </dl>
@@ -827,69 +806,72 @@
         </li>
       </ul>
 
-      <p>Special Notes:</p>
+      <p>Other things you should be aware of:</p>
 
       <ol>
         <li>The variables SCRIPT_FILENAME and REQUEST_FILENAME
-        contain the same value, <em>i.e.</em>, the value of the
+        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 just the commonly known CGI variable name
-        while the second is the consistent counterpart to
+        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>).</li>
 
-        <li>There is the special format:
-        <code>%{ENV:variable}</code> where <em>variable</em> can be
-        any environment variable. This is looked-up via internal
+        <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>There is the special format: 
-        <code>%{SSL:variable}</code> where <em>variable</em> is the
+        <li>
+        <code>%{SSL:variable}</code>, where <em>variable</em> is the
         name of an <a href="mod_ssl.html#envvars">SSL environment
-        variable</a>; this can be used whether or not
+        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>There is the special format:
-        <code>%{HTTP:header}</code> where <em>header</em> can be
-        any HTTP MIME-header name. This is looked-up from the HTTP
-        request. Example: <code>%{HTTP:Proxy-Connection}</code> is
+        <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>''.</li>
 
-        <li>There is the special format
-        <code>%{LA-U:variable}</code> for look-aheads which perform
+        <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>. Use this when you want to use a
-        variable for rewriting which is actually set later in an
-        API phase and thus is not available at the current stage.
-        For instance when you want to rewrite according to the
+	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 have
-        to use <code>%{LA-U:REMOTE_USER}</code> because this
-        variable is set by the authorization phases which come
-        <em>after</em> the URL translation phase where mod_rewrite
-        operates. On the other hand, because mod_rewrite implements
+        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> there.</li>
+	<code>%{REMOTE_USER}</code> in that context.</p></li>
 
-        <li>There is the special format:
-        <code>%{LA-F:variable}</code> which performs an internal
-        (filename-based) sub-request to determine the final value
-        of <em>variable</em>. Most of the time this is the same as
+        <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,
-      <em>i.e.</em>, a regular expression which is applied to the
-      current instance of the <em>TestString</em>, <em>i.e.</em>,
-      <em>TestString</em> is evaluated and then matched against
+       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
@@ -907,98 +889,94 @@
           use one of the following: 
 
           <ul>
-            <li>'<strong>&lt;CondPattern</strong>' (is lexically
-            lower)<br />
-             Treats the <em>CondPattern</em> as a plain string and
-            compares it lexically to <em>TestString</em>. True if
-            <em>TestString</em> is lexically lower than
+            <li>'<strong>&lt;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>&gt;CondPattern</strong>' (is lexically
-            greater)<br />
-             Treats the <em>CondPattern</em> as a plain string and
-            compares it lexically to <em>TestString</em>. True if
-            <em>TestString</em> is lexically greater than
+            <li>'<strong>&gt;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>' (is lexically
+            <li>'<strong>=CondPattern</strong>' (lexicographically
             equal)<br />
-             Treats the <em>CondPattern</em> as a plain string and
-            compares it lexically to <em>TestString</em>. True if
-            <em>TestString</em> is lexically equal to
-            <em>CondPattern</em>, i.e the two strings are exactly
-            equal (character by character). If <em>CondPattern</em>
-            is just <code>""</code> (two quotation marks) this
+            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
-            if it exists and is a directory.</li>
+            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
-            if it exists and is a regular file.</li>
+            whether or not it exists, and is a regular file.</li>
 
-            <li>'<strong>-s</strong>' (is regular file with
+            <li>'<strong>-s</strong>' (is regular file, with
             <strong>s</strong>ize)<br />
-             Treats the <em>TestString</em> as a pathname and tests
-            if it exists and is a regular file with size greater
+            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
-            if it exists and is a symbolic link.</li>
+            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
-            if it exists and has execution permissions. These permissions
-            are determined depending on the underlying OS.</li>
+	    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
+            <li>'<strong>-F</strong>' (is existing file, via
             subrequest)<br />
-             Checks if <em>TestString</em> is a valid file and
+            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 determine the check, so use it with care
-            because it decreases your servers performance!</li>
+            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
+            <li>'<strong>-U</strong>' (is existing URL, via
             subrequest)<br />
-             Checks if <em>TestString</em> is a valid URL and
+            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 determine the check, so use it with care
-            because it decreases your server's performance!</li>
+            subrequest to do the check, so use it with care - 
+            it can impact your server's performance!</li>
           </ul>
 
-<note><title>Notice</title>
+<note><title>Note:</title>
               All of these tests can
               also be prefixed by an exclamation mark ('!') to
               negate their meaning.
 </note>
         </li>
-      </ol>
-
-      <p>Additionally you can set special flags for
-      <em>CondPattern</em> by appending</p>
 
-      <p class="indent">
+	<li>You can also set special flags for
+      <em>CondPattern</em> by appending
         <strong><code>[</code><em>flags</em><code>]</code></strong>
-      </p>
-
-      <p>as the third argument to the <code>RewriteCond</code>
-      directive. <em>Flags</em> is a comma-separated list of the
-      following flags:</p>
+      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:</li>
 
       <ul>
         <li>'<strong><code>nocase|NC</code></strong>'
         (<strong>n</strong>o <strong>c</strong>ase)<br />
-         This makes the test case-insensitive, <em>i.e.</em>, there
-        is no difference between 'A-Z' and 'a-z' both in the
+        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
@@ -1007,7 +985,7 @@
         <li>
           '<strong><code>ornext|OR</code></strong>'
           (<strong>or</strong> next condition)<br />
-           Use this to combine rule conditions with a local OR
+          Use this to combine rule conditions with a local OR
           instead of the implicit AND. Typical example: 
 
 <example>
@@ -1019,10 +997,11 @@
 </pre>
 </example>
 
-          Without this flag you would have to write the cond/rule
-          three times.
+          Without this flag you would have to write the condition/rule
+          pair three times.
         </li>
       </ul>
+     </ol>
 
       <p><strong>Example:</strong></p>
 
@@ -1042,13 +1021,16 @@
 </pre>
 </example>
 
-        <p>Interpretation: If you use Netscape Navigator as your
-        browser (which identifies itself as 'Mozilla'), then you
-        get the max homepage, which includes Frames, <em>etc.</em>
-        If you use the Lynx browser (which is Terminal-based), then
-        you get the min homepage, which contains no images, no
-        tables, <em>etc.</em> If you use any other browser you get
-        the standard homepage.</p>
+        <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>
 
 </usage>
 
@@ -1066,57 +1048,55 @@
 
 <usage>
       <p>The <directive>RewriteRule</directive> directive is the real
-      rewriting workhorse. The directive can occur more than once.
-      Each directive then defines one single rewriting rule. The
-      <strong>definition order</strong> of these rules is
-      <strong>important</strong>, because this order is used when
-      applying the rules at run-time.</p>
+      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> which gets applied to the current URL. Here
-      ``current'' means the value of the URL when this rule gets
+      expression</a>, which is applied to the current URL.
+      ``Current'' means the value of the URL when this rule is
       applied. This may not be the originally requested URL,
-      because any number of rules may already have matched and made
-      alterations to it.</p>
+      which may already have matched a previous rule, and have been
+      altered.</p>
 
-      <p>Some hints about the syntax of <glossary ref="regex">regular 
+      <p>Some hints on the syntax of <glossary ref="regex">regular 
       expressions</glossary>:</p>
 
 <note><pre>
 <strong>Text:</strong>
   <strong><code>.</code></strong>           Any single character
-  <strong><code>[</code></strong>chars<strong><code>]</code></strong>     Character class: One  of chars
-  <strong><code>[^</code></strong>chars<strong><code>]</code></strong>    Character class: None of chars
+  <strong><code>[</code></strong>chars<strong><code>]</code></strong>     Character class: Any character of the class ``chars''
+  <strong><code>[^</code></strong>chars<strong><code>]</code></strong>    Character class: Not a character of the class ``chars''
   text1<strong><code>|</code></strong>text2 Alternative: text1 or text2
 
 <strong>Quantifiers:</strong>
-  <strong><code>?</code></strong>           0 or 1 of the preceding text
-  <strong><code>*</code></strong>           0 or N of the preceding text (N &gt; 0)
-  <strong><code>+</code></strong>           1 or N of the preceding text (N &gt; 1)
+  <strong><code>?</code></strong>           0 or 1 occurrences of the preceding text
+  <strong><code>*</code></strong>           0 or N occurrences of the preceding text (N &gt; 0)
+  <strong><code>+</code></strong>           1 or N occurrences of the preceding text (N &gt; 1)
 
 <strong>Grouping:</strong>
   <strong><code>(</code></strong>text<strong><code>)</code></strong>      Grouping of text
-              (either to set the borders of an alternative or
-              for making backreferences where the <strong>N</strong>th group can 
-              be used on the RHS of a RewriteRule with <code>$</code><strong>N</strong>)
+              (used either to set the borders of an alternative as above, or
+              to make backreferences, where the <strong>N</strong>th group can 
+              be referred to on the RHS of a RewriteRule as <code>$</code><strong>N</strong>)
 
 <strong>Anchors:</strong>
-  <strong><code>^</code></strong>           Start of line anchor
-  <strong><code>$</code></strong>           End   of line anchor
+  <strong><code>^</code></strong>           Start-of-line anchor
+  <strong><code>$</code></strong>           End-of-line anchor
 
 <strong>Escaping:</strong>
-  <strong><code>\</code></strong>char       escape that particular char
-              (for instance to specify the chars "<code>.[]()</code>" <em>etc.</em>)
+  <strong><code>\</code></strong>char       escape the given char
+              (for instance, to specify the chars "<code>.[]()</code>" <em>etc.</em>)
 </pre></note>
 
-      <p>For more information about regular expressions have a look at the
+      <p>For more information about regular expressions, have a look at the
       perl regular expression manpage ("<a
       href="http://www.perldoc.com/perl5.6.1/pod/perlre.html">perldoc
       perlre</a>"). If you are interested in more detailed
       information about regular expressions and their variants
-      (POSIX regex <em>etc.</em>) have a look at the
-      following dedicated book on this topic:</p>
+      (POSIX regex etc.) the following book is dedicated to this topic:</p>
 
       <p class="indent">
         <em>Mastering Regular Expressions, 2nd Edition</em><br />
@@ -1125,34 +1105,32 @@
          ISBN 0-596-00289-0<br />
       </p>
 
-      <p>Additionally in mod_rewrite the NOT character
-      ('<code>!</code>') is a possible pattern prefix. This gives
-      you the ability to negate a pattern; to say, for instance:
+      <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>
 
-<note><title>Notice</title>
-When using the NOT character
-          to negate a pattern you cannot have grouped wildcard
-          parts in the pattern. This is impossible because when the
-          pattern does NOT match, there are no contents for the
-          groups. In consequence, if negated patterns are used, you
-          cannot use <code>$N</code> in the substitution
-          string!
+<note><title>Note</title>
+When using the NOT character to negate a pattern, you cannot include 
+grouped wildcard parts in that pattern. This is because, when the 
+pattern does NOT match (ie, the negation matches), there are no 
+contents for the groups. Thus, if negated patterns are used, you
+cannot use <code>$N</code> in the substitution string!
 </note>
 
-      <p><a id="rhs" name="rhs"><em>Substitution</em></a> of a
-      rewriting rule is the string which is substituted for (or
-      replaces) the original URL for which <em>Pattern</em>
-      matched. Beside plain text you can use</p>
+      <p>The <a id="rhs" name="rhs"><em>substitution</em></a> of a
+      rewrite rule is the string which is substituted for (or
+      replaces) the original URL which <em>Pattern</em>
+      matched. In addition to plain text, it can include</p>
 
       <ol>
-        <li>back-references <code>$N</code> to the RewriteRule
+        <li>back-references (<code>$N</code>) to the RewriteRule
         pattern</li>
 
-        <li>back-references <code>%N</code> to the last matched
+        <li>back-references (<code>%N</code>) to the last matched
         RewriteCond pattern</li>
 
         <li>server-variables as in rule condition test-strings
@@ -1161,75 +1139,38 @@
         <li><a href="#mapfunc">mapping-function</a> calls
         (<code>${mapname:key|default}</code>)</li>
       </ol>
-      <p>Back-references are <code>$</code><strong>N</strong>
-      (<strong>N</strong>=0..9) identifiers which will be replaced
+      <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 of
-      the above list. </p>
+      These three types of variables are expanded in the order above.</p>
 
-      <p>As already mentioned above, all the rewriting rules are
-      applied to the <em>Substitution</em> (in the order of
-      definition in the config file). The URL is <strong>completely
+      <p>As already mentioned, all rewrite rules are
+      applied to the <em>Substitution</em> (in the 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 goes on until there are no more rules
-      unless explicitly terminated by a
+      rewriting process continues until all rules have been applied,
+      or it is explicitly terminated by a
       <code><strong>L</strong></code> flag - see below.</p>
 
       <p>There is a special substitution string named
       '<code>-</code>' which means: <strong>NO
-      substitution</strong>! Sounds silly? No, it is useful to
-      provide rewriting rules which <strong>only</strong> match
-      some URLs but do no substitution, <em>e.g.</em>, in
-      conjunction with the <strong>C</strong> (chain) flag to be
-      able to have more than one pattern to be applied before a
-      substitution occurs.</p>
-
-<note><title>Query String</title>
-      <p>The <em>Pattern</em> will not match against the query string.
-      Instead, you must use a <directive
-      module="mod_rewrite">RewriteCond</directive> with the
-      <code>%{QUERY_STRING}</code> variable.  You can, however, 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.  To
-      combine a new query string with an old one, use the
-      <code>[QSA]</code> flag (see below).</p>
-</note>
+      substitution</strong>! This is useful in providing
+      rewriting rules which <strong>only</strong> match
+      URLs but do not substitute anything for them. It is commonly used 
+      in conjunction with the <strong>C</strong> (chain) flag, in order 
+      to apply more than one pattern before substitution occurs.</p>
 
-<note><title>Substitution of Absolute URLs</title>
-          <p>There is a special feature:
-          When you prefix a substitution field with
-          <code>http://</code><em>thishost</em>[<em>:thisport</em>]
-          then <strong>mod_rewrite</strong> automatically strips it
-          out. This auto-reduction on implicit external redirect
-          URLs is a useful and important feature when used in
-          combination with a mapping-function which generates the
-          hostname part. Have a look at the first example in the
-          example section below to understand this.</p>
-
-          <p><strong>Remember:</strong> An unconditional external
-          redirect to your own server will not work with the prefix
-          <code>http://thishost</code> because of this feature. To
-          achieve such a self-redirect, you have to use the
-          <strong>R</strong>-flag (see below).</p>
-</note>
 
       <p>Additionally you can set special <a name="rewriteflags"
       id="rewriteflags">flags</a> for <em>Substitution</em> by 
-      appending</p>
-
-      <p class="indent">
-        <strong><code>[</code><em>flags</em><code>]</code></strong>
-      </p>
-      <p>
+      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 of the
+      directive. <em>Flags</em> is a comma-separated list of any of the
       following flags: </p>
 
       <ul>
@@ -1237,52 +1178,51 @@
         (<strong>c</strong>hained with next rule)<br />
          This flag chains the current rule with the next rule
         (which itself can be chained with the following rule,
-        <em>etc.</em>). This has the following effect: if a rule
-        matches, then processing continues as usual, <em>i.e.</em>,
+        and so on). This has the following effect: if a rule
+        matches, then processing continues as usual - 
         the flag has no effect. If the rule does
         <strong>not</strong> match, then all following chained
-        rules are skipped. For instance, use it to remove the
-        ``<code>.www</code>'' part inside a per-directory rule set
+        rules are skipped. For instance, it can be used to remove the
+        ``<code>.www</code>'' part, inside a per-directory rule set,
         when you let an external redirect happen (where the
-        ``<code>.www</code>'' part should not to occur!).</li>
+        ``<code>.www</code>'' part should not occur!).</li>
 
         <li>
 		'<strong><code>cookie|CO=</code></strong><em>NAME</em>:<em>VAL</em>:<em>domain</em>[:<em>lifetime</em>[:<em>path</em>]]'
         (set <strong>co</strong>okie)<br />
-        This sets a cookie on the client's browser.  The cookie's name
+        This sets a cookie in the client's browser.  The cookie's name
         is specified by <em>NAME</em> and the value is
         <em>VAL</em>. The <em>domain</em> field is the domain of the
-        cookie, such as '.apache.org',the optional <em>lifetime</em>
+        cookie, such as '.apache.org', the optional <em>lifetime</em>
 	is the lifetime of the cookie in minutes, and the optional 
 	<em>path</em> is the path of the cookie</li>
 
         <li>
         '<strong><code>env|E=</code></strong><em>VAR</em>:<em>VAL</em>'
         (set <strong>e</strong>nvironment variable)<br />
-         This forces an environment variable named <em>VAR</em> to
+        This forces an environment variable named <em>VAR</em> to
         be set to the value <em>VAL</em>, where <em>VAL</em> can
-        contain regexp backreferences <code>$N</code> and
-        <code>%N</code> which will be expanded. You can use this
-        flag more than once to set more than one variable. The
-        variables can be later dereferenced in many situations, but
-        usually from within XSSI (via <code>&lt;!--#echo
-        var="VAR"--&gt;</code>) or CGI (<em>e.g.</em>
-        <code>$ENV{'VAR'}</code>). Additionally you can dereference
-        it in a following RewriteCond pattern via
-        <code>%{ENV:VAR}</code>. Use this to strip but remember
-        information from URLs.</li>
+        contain regexp backreferences (<code>$N</code> and
+        <code>%N</code>) which will be expanded. You can use this
+        flag more than once, to set more than one variable. The
+        variables can later be dereferenced in many situations, most commonly
+	from within XSSI (via <code>&lt;!--#echo
+        var="VAR"--&gt;</code>) or CGI (<code>$ENV{'VAR'}</code>). 
+	You can also dereference the variable in a later RewriteCond pattern, using
+        <code>%{ENV:VAR}</code>. Use this to strip 
+        information from URLs, while maintaining a record of that information.</li>
 
         <li>'<strong><code>forbidden|F</code></strong>' (force URL
         to be <strong>f</strong>orbidden)<br />
-         This forces the current URL to be forbidden,
-        <em>i.e.</em>, it immediately sends back a HTTP response of
-        403 (FORBIDDEN). Use this flag in conjunction with
+        This forces the current URL to be forbidden - it immediately 
+	sends back a HTTP response of 403 (FORBIDDEN). 
+	Use this flag in conjunction with
         appropriate RewriteConds to conditionally block some
         URLs.</li>
 
         <li>'<strong><code>gone|G</code></strong>' (force URL to be
         <strong>g</strong>one)<br />
-         This forces the current URL to be gone, <em>i.e.</em>, it
+        This forces the current URL to be gone - it
         immediately sends back a HTTP response of 410 (GONE). Use
         this flag to mark pages which no longer exist as gone.</li>
 
@@ -1291,17 +1231,18 @@
         (force Content <strong>h</strong>andler)<br />
          Force the Content-handler of the target file to be
         <em>Content-handler</em>. For instance, this can be used to
-        simulate the <code>mod_alias</code> directive
-        <code>ScriptAlias</code> which internally forces all files
+        simulate the <module>mod_alias</module> directive
+	<directive module="mod_alias">ScriptAlias</directive>, 
+	which internally forces all files
         inside the mapped directory to have a handler of
         ``<code>cgi-script</code>''.</li>
 
         <li>'<strong><code>last|L</code></strong>'
         (<strong>l</strong>ast rule)<br />
-         Stop the rewriting process here and don't apply any more
-        rewriting rules. This corresponds to the Perl
+        Stop the rewriting process here and don't apply any more
+        rewrite rules. This corresponds to the Perl
         <code>last</code> command or the <code>break</code> command
-        from the C language. Use this flag to prevent the currently
+        in C. Use this flag to prevent the currently
         rewritten URL from being rewritten further by following
         rules. For example, use it to rewrite the root-path URL
         ('<code>/</code>') to a real one, <em>e.g.</em>,
@@ -1309,20 +1250,20 @@
 
         <li>'<strong><code>next|N</code></strong>'
         (<strong>n</strong>ext round)<br />
-         Re-run the rewriting process (starting again with the
-        first rewriting rule). Here the URL to match is again not
-        the original URL but the URL from the last rewriting rule.
+        Re-run the rewriting process (starting again with the
+        first rewriting rule). This time, the URL to match is no longer
+        the original URL, but rather the URL returned by the last rewriting rule.
         This corresponds to the Perl <code>next</code> command or
-        the <code>continue</code> command from the C language. Use
-        this flag to restart the rewriting process, <em>i.e.</em>,
+        the <code>continue</code> command in C. Use
+        this flag to restart the rewriting process -
         to immediately go to the top of the loop.<br />
-         <strong>But be careful not to create an infinite
+         <strong>Be careful not to create an infinite
         loop!</strong></li>
 
         <li>'<strong><code>nocase|NC</code></strong>'
         (<strong>n</strong>o <strong>c</strong>ase)<br />
-         This makes the <em>Pattern</em> case-insensitive,
-        <em>i.e.</em>, there is no difference between 'A-Z' and
+        This makes the <em>Pattern</em> case-insensitive,
+        ignoring difference between 'A-Z' and
         'a-z' when <em>Pattern</em> is matched against the current
         URL.</li>
 
@@ -1330,61 +1271,58 @@
           '<strong><code>noescape|NE</code></strong>'
           (<strong>n</strong>o URI <strong>e</strong>scaping of
           output)<br />
-           This flag keeps mod_rewrite from applying the usual URI
+          This flag prevents mod_rewrite from applying the usual URI
           escaping rules to the result of a rewrite. Ordinarily,
           special characters (such as '%', '$', ';', and so on)
           will be escaped into their hexcode equivalents ('%25',
           '%24', and '%3B', respectively); this flag prevents this
-          from being done. This allows percent symbols to appear in
+          from happening. This allows percent symbols to appear in
           the output, as in 
 <example>
     RewriteRule /foo/(.*) /bar?arg=P1\%3d$1 [R,NE]
 </example>
-
           which would turn '<code>/foo/zed</code>' into a safe
           request for '<code>/bar?arg=P1=zed</code>'. 
         </li>
 
         <li>
-          '<strong><code>nosubreq|NS</code></strong>' (used only if
-          <strong>n</strong>o internal
-          <strong>s</strong>ub-request)<br />
-           This flag forces the rewriting engine to skip a
+          '<strong><code>nosubreq|NS</code></strong>'
+          (<strong>n</strong>ot for internal
+          <strong>s</strong>ub-requests)<br />
+          This flag forces the rewriting engine to skip a
           rewriting rule if the current request is an internal
           sub-request. For instance, sub-requests occur internally
-          in Apache when <code>mod_include</code> tries to find out
+          in Apache when <module>mod_include</module> tries to find out
           information about possible directory default files
-          (<code>index.xxx</code>). On sub-requests it is not
-          always useful and even sometimes causes a failure to if
+          (<code>index.xxx</code> files). On sub-requests it is not
+          always useful, and can even cause errors, if
           the complete set of rules are applied. Use this flag to
           exclude some rules.<br />
-           
-
-          <p>Use the following rule for your decision: whenever you
-          prefix some URLs with CGI-scripts to force them to be
-          processed by the CGI-script, the chance is high that you
-          will run into problems (or even overhead) on
-          sub-requests. In these cases, use this flag.</p>
+          To decide whether or not to use this rule: if you
+          prefix URLs with CGI-scripts, to force them to be
+	  processed by the CGI-script, it's likely that you 
+          will run into problems (or significant overhead) on
+          sub-requests. In these cases, use this flag.
         </li>
 
         <li>
           '<strong><code>proxy|P</code></strong>' (force
           <strong>p</strong>roxy)<br />
-           This flag forces the substitution part to be internally
-          forced as a proxy request and immediately (<em>i.e.</em>,
-          rewriting rule processing stops here) put through the <a
-          href="mod_proxy.html">proxy module</a>. You have to make
+          This flag forces the substitution part to be internally
+	  sent as a proxy request and immediately (rewrite 
+	  processing stops here) put through the <a
+          href="mod_proxy.html">proxy module</a>. You must make
           sure that the substitution string is a valid URI
-          (<em>e.g.</em>, typically starting with
+          (typically starting with
           <code>http://</code><em>hostname</em>) which can be
-          handled by the Apache proxy module. If not you get an
+          handled by the Apache proxy module. If not, you will get an
           error from the proxy module. Use this flag to achieve a
           more powerful implementation of the <a
           href="mod_proxy.html#proxypass">ProxyPass</a> directive,
-          to map some remote stuff into the namespace of the local
+          to map remote content into the namespace of the local
           server. 
 
-          <p>Notice: <module>mod_proxy</module> must be enabled in order
+          <p>Note: <module>mod_proxy</module> must be enabled in order
           to use this flag.</p>
         </li>
 
@@ -1392,82 +1330,80 @@
           '<strong><code>passthrough|PT</code></strong>'
           (<strong>p</strong>ass <strong>t</strong>hrough to next
           handler)<br />
-           This flag forces the rewriting engine to set the
+           This flag forces the rewrite engine to set the
           <code>uri</code> field of the internal
           <code>request_rec</code> structure to the value of the
           <code>filename</code> field. This flag is just a hack to
-          be able to post-process the output of
-          <code>RewriteRule</code> directives by
+          enable post-processing of the output of
+          <code>RewriteRule</code> directives, using
           <code>Alias</code>, <code>ScriptAlias</code>,
-          <code>Redirect</code>, <em>etc.</em> directives from
-          other URI-to-filename translators. A trivial example to
-          show the semantics: If you want to rewrite
-          <code>/abc</code> to <code>/def</code> via the rewriting
-          engine of <code>mod_rewrite</code> and then
-          <code>/def</code> to <code>/ghi</code> with
-          <code>mod_alias</code>: 
+          <code>Redirect</code>, and other directives from
+          various URI-to-filename translators. For example, to rewrite
+          <code>/abc</code> to <code>/def</code> using
+          <module>mod_rewrite</module>, and then
+          <code>/def</code> to <code>/ghi</code> using
+          <module>mod_alias</module>: 
 <example>
     RewriteRule ^/abc(.*)  /def$1 [PT]<br />
     Alias       /def       /ghi
 </example>
-          If you omit the <code>PT</code> flag then
-          <code>mod_rewrite</code> will do its job fine,
-          <em>i.e.</em>, it rewrites <code>uri=/abc/...</code> to
+          If you omit the <code>PT</code> flag,
+          <code>mod_rewrite</code> will rewrite 
+	  <code>uri=/abc/...</code> to
           <code>filename=/def/...</code> as a full API-compliant
           URI-to-filename translator should do. Then
-          <code>mod_alias</code> comes and tries to do a
-          URI-to-filename transition which will not work. 
+          <code>mod_alias</code> will try to do a
+          URI-to-filename transition, which will fail. 
 
-          <p>Note: <strong>You have to use this flag if you want to
-          intermix directives of different modules which contain
+          <p>Note: <strong>You must use this flag if you want to
+          mix directives from different modules which allow
           URL-to-filename translators</strong>. The typical example
-          is the use of <code>mod_alias</code> and
-          <code>mod_rewrite</code>..</p>
+          is the use of <module>mod_alias</module> and
+          <module>mod_rewrite</module>.</p>
         </li>
 
         <li>'<strong><code>qsappend|QSA</code></strong>'
         (<strong>q</strong>uery <strong>s</strong>tring
         <strong>a</strong>ppend)<br />
-         This flag forces the rewriting engine to append a query
-        string part in the substitution string to the existing one
+        This flag forces the rewrit engine to append a query
+        string part of the substitution string to the existing string,
         instead of replacing it. Use this when you want to add more
         data to the query string via a rewrite rule.</li>
 
          <li>'<strong><code>redirect|R</code>
           [=<em>code</em>]</strong>' (force <a id="redirect"
           name="redirect"><strong>r</strong>edirect</a>)<br />
-           Prefix <em>Substitution</em> with
+          Prefix <em>Substitution</em> with
           <code>http://thishost[:thisport]/</code> (which makes the
           new URL a URI) to force a external redirection. If no
-          <em>code</em> is given a HTTP response of 302 (MOVED
-          TEMPORARILY) is used. If you want to use other response
-          codes in the range 300-400 just specify them as a number
+          <em>code</em> is given, a HTTP response of 302 (MOVED
+          TEMPORARILY) will be returned. If you want to use other response
+          codes in the range 300-400, simply specify the appropriate number
           or use one of the following symbolic names:
           <code>temp</code> (default), <code>permanent</code>,
-          <code>seeother</code>. Use it for rules which should
-          canonicalize the URL and give it back to the client,
-          <em>e.g.</em>, translate ``<code>/~</code>'' into
-          ``<code>/u/</code>'' or always append a slash to
+          <code>seeother</code>. Use this for rules to
+          canonicalize the URL and return it to the client - to 
+	  translate ``<code>/~</code>'' into
+          ``<code>/u/</code>'', or to always append a slash to
           <code>/u/</code><em>user</em>, etc.<br />
            
-
           <p><strong>Note:</strong> When you use this flag, make
-          sure that the substitution field is a valid URL! If not,
-          you are redirecting to an invalid location! And remember
-          that this flag itself only prefixes the URL with
-          <code>http://thishost[:thisport]/</code>, rewriting
-          continues. Usually you also want to stop and do the
-          redirection immediately. To stop the rewriting you also
-          have to provide the 'L' flag.</p>
+          sure that the substitution field is a valid URL! Otherwise,
+          you will be redirecting to an invalid location. Remember
+          that this flag on its own will only prepend
+          <code>http://thishost[:thisport]/</code> to the URL, and rewriting
+	  will continue. Usually, you will want to stop rewriting at this point,
+	  and redirect immediately. To stop rewriting, you should add 
+	  the 'L' flag.</p>
         </li>
 
         <li>'<strong><code>skip|S</code></strong>=<em>num</em>'
         (<strong>s</strong>kip next rule(s))<br />
-         This flag forces the rewriting engine to skip the next
-        <em>num</em> rules in sequence when the current rule
+        This flag forces the rewriting engine to skip the next
+        <em>num</em> rules in sequence, if the current rule
         matches. Use this to make pseudo if-then-else constructs:
         The last rule of the then-clause becomes
-        <code>skip=N</code> where N is the number of rules in the
+        <code>skip=N</code>, where N is the number of rules in the
         else-clause. (This is <strong>not</strong> the same as the
         'chain|C' flag!)</li>
 
@@ -1475,8 +1411,8 @@
         '<strong><code>type|T</code></strong>=<em>MIME-type</em>'
         (force MIME <strong>t</strong>ype)<br />
          Force the <glossary>MIME-type</glossary> of the target file to be
-        <em>MIME-type</em>. For instance, this can be used to
-        setup the content-type based on some conditions.
+        <em>MIME-type</em>. This can be used to
+        set up the content-type based on some conditions.
         For example, the following snippet allows <code>.php</code> files to
         be <em>displayed</em> by <code>mod_php</code> if they are called with
         the <code>.phps</code> extension:
@@ -1484,40 +1420,70 @@
             RewriteRule ^(.+\.php)s$ $1 [T=application/x-httpd-php-source]
         </example>
         </li>
-
-
       </ul>
 
-<note><title>Note</title> Never forget that <em>Pattern</em> is
+<note><title>Note: Enabling rewrites in per-directory context</title>
+ To enable the rewrite engine
+          for per-directory configuration files you need to set
+          ``<code>RewriteEngine On</code>'' in these files
+          <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.
+</note>
+
+<note><title>Note: Pattern matching in per-directory context</title> 
+	Never forget that <em>Pattern</em> is
 applied to a complete URL in per-server configuration
-files. <strong>But in per-directory configuration files, the
+files. <strong>However, in per-directory configuration files, the
 per-directory prefix (which always is the same for a specific
-directory!) is automatically <em>removed</em> for the pattern matching
+directory) is automatically <em>removed</em> for the pattern matching
 and automatically <em>added</em> after the substitution has been
-done.</strong> This feature is essential for many sorts of rewriting,
-because without this prefix stripping you have to match the parent
-directory which is not always possible.
+done.</strong> 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.
 
             <p>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 flag
-            <strong>P</strong> is used!) is forced!</p>
+            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!</p>
 </note>
 
-<note><title>Note</title>
- To enable the rewriting engine
-          for per-directory configuration files you need to set
-          ``<code>RewriteEngine On</code>'' in these files
-          <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 rewriting engine. This restriction is
-          needed for security reasons.
+<note><title>Note: Substitution of Absolute URLs</title>
+          <p>
+          When you prefix a substitution field with
+	  <code>http://thishost[:thisport]</code>, <module
+	  >mod_rewrite</module> will automatically strip that
+          out. This auto-reduction on URLs with an implicit 
+          external redirect is most useful in
+          combination with a mapping-function which generates the
+	  hostname part.</p>
+
+          <p><strong>Remember:</strong> An unconditional external
+          redirect to your own server will not work with the prefix
+          <code>http://thishost</code> because of this feature. To
+          achieve such a self-redirect, you have to use the
+          <strong>R</strong>-flag (see below).</p>
+</note>
+
+<note><title>Note: Query String</title>
+      <p>The <em>Pattern</em> will not be matched against the query string.
+      To do this, you must use a <directive
+      module="mod_rewrite">RewriteCond</directive> with the
+      <code>%{QUERY_STRING}</code> variable. 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 (see above).</p>
 </note>
 
-      <p>Here are all possible substitution combinations and their
+     <p>Here are all possible substitution combinations and their
       meanings:</p>
 
       <p><strong>Inside per-server configuration
@@ -1529,25 +1495,25 @@
 <note><pre>
 <strong>Given Rule</strong>                                      <strong>Resulting Substitution</strong>
 ----------------------------------------------  ----------------------------------
-^/somepath(.*) otherpath$1                      not supported, because invalid!
+^/somepath(.*) otherpath$1                      invalid, not supported
 
-^/somepath(.*) otherpath$1  [R]                 not supported, because invalid!
+^/somepath(.*) otherpath$1  [R]                 invalid, not supported
 
-^/somepath(.*) otherpath$1  [P]                 not supported, because invalid!
+^/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]                 not supported, because silly!
+^/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]  not supported, because silly!
+^/somepath(.*) http://thishost/otherpath$1 [P]  doesn't make sense, not supported
 ----------------------------------------------  ----------------------------------
 ^/somepath(.*) http://otherhost/otherpath$1     http://otherhost/otherpath/pathinfo
                                                 via external redirection
@@ -1562,8 +1528,7 @@
 
       <p><strong>Inside per-directory configuration for
       <code>/somepath</code><br />
-       (<em>i.e.</em>, file <code>.htaccess</code> in dir
-      <code>/physical/path/to/somepath</code> containing
+       (<code>/physical/path/to/somepath/.htacccess</code>, with
       <code>RewriteBase /somepath</code>)<br />
        for request ``<code>GET
       /somepath/localpath/pathinfo</code>'':</strong><br /> 
@@ -1577,21 +1542,21 @@
 ^localpath(.*) otherpath$1  [R]                 http://thishost/somepath/otherpath/pathinfo
                                                 via external redirection
 
-^localpath(.*) otherpath$1  [P]                 not supported, because silly!
+^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]                 not supported, because silly!
+^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]  not supported, because silly!
+^localpath(.*) http://thishost/otherpath$1 [P]  doesn't make sense, not supported
 ----------------------------------------------  ----------------------------------
 ^localpath(.*) http://otherhost/otherpath$1     http://otherhost/otherpath/pathinfo
                                                 via external redirection
@@ -1603,35 +1568,6 @@
 ^localpath(.*) http://otherhost/otherpath$1 [P] http://otherhost/otherpath/pathinfo
                                                 via internal proxy
 </pre></note>
-
-      <p><strong>Example:</strong></p>
-
-      <p>We want to rewrite URLs of the form </p>
-
-        <p class="indent">
-          <code>/</code> <em>Language</em> <code>/~</code>
-          <em>Realname</em> <code>/.../</code> <em>File</em>
-        </p>
-
-        <p>into </p>
-
-        <p class="indent">
-          <code>/u/</code> <em>Username</em> <code>/.../</code>
-          <em>File</em> <code>.</code> <em>Language</em>
-        </p>
-
-        <p>We take the rewrite mapfile from above and save it under
-        <code>/path/to/file/map.txt</code>. Then we only have to
-        add the following lines to the Apache server configuration
-        file:</p>
-
-<example>
-<pre>
-RewriteLog   /path/to/file/rewrite.log
-RewriteMap   real-to-user               txt:/path/to/file/map.txt
-RewriteRule  ^/([^/]+)/~([^/]+)/(.*)$   /u/${real-to-user:$2|nobody}/$3.$1
-</pre>
-   </example>
   </usage>
  </directivesynopsis>
 </modulesynopsis>



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