Added documentation of zlib runtime configuration options.

git-svn-id: https://svn.php.net/repository/phpdoc/en/trunk@90218 c90b9560-bf6c-de11-be94-00142212c4b1

reference/zlib/reference.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="iso-8859-1"?>
-<!-- $Revision: 1.5 $ -->
+<!-- $Revision: 1.6 $ -->
  <reference id="ref.zlib">
   <title>Zlib Compression Functions</title>
   <titleabbrev>Zlib</titleabbrev>
@@ -46,7 +46,85 @@
 
    <section id="zlib.configuration">
     &reftitle.runtime;
-    &no.config;
+    <para>
+     The zlib extension offers the option to transparently compress
+     your pages on-the-fly, if the requesting browser supports
+     this. Therefore there are two options in the <link
+     linkend="configuration.file">configuration file</link> &php.ini;.
+
+     <table>
+      <title>Zlib Configuration Options</title>
+      <tgroup cols="3">
+       <thead>
+        <row>
+         <entry>Name</entry>
+         <entry>Default</entry>
+         <entry>Changeable</entry>
+        </row>
+       </thead>
+       <tbody>
+        <row>
+         <entry>zlib.output_compression</entry>
+         <entry>"0"</entry>
+         <entry>PHP_INI_ALL</entry>
+        </row>
+        <row>
+         <entry>zlib.output_compression_level</entry>
+         <entry>"-1"</entry>
+         <entry>PHP_INI_ALL</entry>
+        </row>
+       </tbody>
+      </tgroup>
+     </table>
+
+     For further details and definition of the PHP_INI_* constants see
+     <function>ini_set</function>.
+   </para>
+
+   <para>
+    Here is a short explanation of the configuration directives.
+    <variablelist>
+     <varlistentry id="ini.zlib.output_compression">
+      <term>
+       <parameter>zlib.output_compression</parameter>
+       <type>boolean</type>/<type>integer</type>
+      </term>
+      <listitem>
+       <para>
+        Whether to transparently compress pages. If this option is set
+        to "On" in &php.ini or the Apache configuration, pages are
+        compressed if the browser sends an "Accept-Encoding: gzip" or
+        "deflate" header. "Content-Encoding: gzip" (respectively
+        "deflate") and "Vary: Accept-Encoding" headers are added to
+        the output.
+       </para>
+       <para>
+        You can use <function>ini_set</function> to disable this in
+        your script if the headers aren't already sent. If you output
+        a "Content-Type: image/" header the compression is disabled,
+        too (in order to circumvent a Netscape bug). You can reenable
+        it, if you add "ini_set('zlib.output_compression', 'On')"
+        after the header call which added the image content-type.
+       </para>
+       <para>
+        This option also accepts integer values instead of boolean
+        "On"/"Off", using this you can set the output buffer size.
+       </para>
+      </listitem>
+     </varlistentry>
+     <varlistentry id="ini.zlib.output_compression_level">
+      <term>
+       <parameter>zlib.output_compression_level</parameter>
+       <type>integer</type>
+      </term>
+      <listitem>
+       <para>
+        Compression level used for transparent output compression.
+       </para>
+      </listitem>
+     </varlistentry>
+    </variablelist>
+    </para>
    </section>
 
    <section id="zlib.resources">