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			343 lines
		
	
	
		
			21 KiB
		
	
	
	
		
			XML
		
	
	
	
	
	
<?xml version="1.0" encoding="ISO-8859-1"?>
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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
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<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"><head><!--
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              This file is generated from xml source: DO NOT EDIT
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        XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
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      -->
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<title>mod_isapi - Apache HTTP Server</title>
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<link href="../style/css/manual.css" rel="stylesheet" media="all" type="text/css" title="Main stylesheet" />
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<link href="../style/css/manual-loose-100pc.css" rel="alternate stylesheet" media="all" type="text/css" title="No Sidebar - Default font size" />
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<link href="../style/css/manual-print.css" rel="stylesheet" media="print" type="text/css" />
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<link href="../images/favicon.ico" rel="shortcut icon" /></head>
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<body>
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<div id="page-header">
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<p class="menu"><a href="../mod/">Modules</a> | <a href="../mod/directives.html">Directives</a> | <a href="../faq/">FAQ</a> | <a href="../glossary.html">Glossary</a> | <a href="../sitemap.html">Sitemap</a></p>
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<p class="apache">Apache HTTP Server Version 2.5</p>
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<img alt="" src="../images/feather.gif" /></div>
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<div class="up"><a href="./"><img title="<-" alt="<-" src="../images/left.gif" /></a></div>
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<div id="path">
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<a href="http://www.apache.org/">Apache</a> > <a href="http://httpd.apache.org/">HTTP Server</a> > <a href="http://httpd.apache.org/docs/">Documentation</a> > <a href="../">Version 2.5</a> > <a href="./">Modules</a></div>
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<div id="page-content">
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<div id="preamble"><h1>Apache Module mod_isapi</h1>
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<div class="toplang">
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<p><span>Available Languages: </span><a href="../en/mod/mod_isapi.html" title="English"> en </a> |
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<a href="../ko/mod/mod_isapi.html" hreflang="ko" rel="alternate" title="Korean"> ko </a></p>
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</div>
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<table class="module"><tr><th><a href="module-dict.html#Description">Description:</a></th><td>ISAPI Extensions within Apache for Windows</td></tr>
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<tr><th><a href="module-dict.html#Status">Status:</a></th><td>Base</td></tr>
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<tr><th><a href="module-dict.html#ModuleIdentifier">Module<EFBFBD>Identifier:</a></th><td>isapi_module</td></tr>
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<tr><th><a href="module-dict.html#SourceFile">Source<EFBFBD>File:</a></th><td>mod_isapi.c</td></tr>
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<tr><th><a href="module-dict.html#Compatibility">Compatibility:</a></th><td>Win32 only</td></tr></table>
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<h3>Summary</h3>
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    <p>This module implements the Internet Server extension API. It
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    allows Internet Server extensions (<em>e.g.</em> ISAPI .dll
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    modules) to be served by Apache for Windows, subject to the
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    noted restrictions.</p>
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    <p>ISAPI extension modules (.dll files) are written by third
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    parties. The Apache Group does not author these modules, so we
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    provide no support for them. Please contact the ISAPI's author
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    directly if you are experiencing problems running their ISAPI
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    extension. <strong>Please <em>do not</em> post such problems to
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    Apache's lists or bug reporting pages.</strong></p>
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</div>
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<div id="quickview"><h3 class="directives">Directives</h3>
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<ul id="toc">
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<li><img alt="" src="../images/down.gif" /> <a href="#isapiappendlogtoerrors">ISAPIAppendLogToErrors</a></li>
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<li><img alt="" src="../images/down.gif" /> <a href="#isapiappendlogtoquery">ISAPIAppendLogToQuery</a></li>
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<li><img alt="" src="../images/down.gif" /> <a href="#isapicachefile">ISAPICacheFile</a></li>
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<li><img alt="" src="../images/down.gif" /> <a href="#isapifakeasync">ISAPIFakeAsync</a></li>
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<li><img alt="" src="../images/down.gif" /> <a href="#isapilognotsupported">ISAPILogNotSupported</a></li>
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<li><img alt="" src="../images/down.gif" /> <a href="#isapireadaheadbuffer">ISAPIReadAheadBuffer</a></li>
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</ul>
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<h3>Topics</h3>
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<ul id="topics">
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<li><img alt="" src="../images/down.gif" /> <a href="#usage">Usage</a></li>
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<li><img alt="" src="../images/down.gif" /> <a href="#notes">Additional Notes</a></li>
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<li><img alt="" src="../images/down.gif" /> <a href="#journal">Programmer's Journal</a></li>
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</ul></div>
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<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
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<div class="section">
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<h2><a name="usage" id="usage">Usage</a></h2>
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    <p>In the server configuration file, use
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    the <code class="directive"><a href="../mod/mod_mime.html#addhandler">AddHandler</a></code> directive to
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    associate ISAPI files with the <code>isapi-handler</code> handler, and map
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    it to them with their file extensions. To enable any .dll file to be
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    processed as an ISAPI extension, edit the httpd.conf file and add the
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    following line:</p>
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    <div class="example"><p><code>
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        AddHandler isapi-handler .dll
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    </code></p></div>
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    <div class="note">In older versions of the Apache server,
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    <code>isapi-isa</code> was the proper handler name, rather than
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    <code>isapi-handler</code>. As of 2.3 development versions of the Apache
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    server, <code>isapi-isa</code> is no longer valid. You will need to
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    change your configuration to use <code>isapi-handler</code>
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    instead.</div>
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    <p>There is no capability within the Apache server to leave a
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    requested module loaded. However, you may preload and keep a
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    specific module loaded by using the following syntax in your
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    httpd.conf:</p>
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    <div class="example"><p><code>
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        ISAPICacheFile c:/WebWork/Scripts/ISAPI/mytest.dll
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    </code></p></div>
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    <p>Whether or not you have preloaded an ISAPI extension, all
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    ISAPI extensions are governed by the same permissions and
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    restrictions as CGI scripts. That is, <code class="directive"><a href="../mod/core.html#options">Options</a></code> <code>ExecCGI</code> must be set for the
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    directory that contains the ISAPI .dll file.</p>
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    <p>Review the <a href="#notes">Additional Notes</a> and the <a href="#journal">Programmer's Journal</a> for additional details
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    and clarification of the specific ISAPI support offered by
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    <code class="module"><a href="../mod/mod_isapi.html">mod_isapi</a></code>.</p>
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</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
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<div class="section">
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<h2><a name="notes" id="notes">Additional Notes</a></h2>
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    <p>Apache's ISAPI implementation conforms to all of the ISAPI
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    2.0 specification, except for some "Microsoft-specific"
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    extensions dealing with asynchronous I/O. Apache's I/O model
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    does not allow asynchronous reading and writing in a manner
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    that the ISAPI could access. If an ISA tries to access
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    unsupported features, including async I/O, a message is placed
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    in the error log to help with debugging. Since these messages
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    can become a flood, the directive <code>ISAPILogNotSupported
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    Off</code> exists to quiet this noise.</p>
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    <p>Some servers, like Microsoft IIS, load the ISAPI extension
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    into the server and keep it loaded until memory usage is too
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    high, or unless configuration options are specified. Apache
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    currently loads and unloads the ISAPI extension each time it is
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    requested, unless the <code class="directive"><a href="#isapicachefile">ISAPICacheFile</a></code> directive is specified.
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    This is inefficient, but Apache's memory model makes this the
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    most effective method. Many ISAPI modules are subtly
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    incompatible with the Apache server, and unloading these
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    modules helps to ensure the stability of the server.</p>
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    <p>Also, remember that while Apache supports ISAPI Extensions,
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    it <strong>does not support ISAPI Filters</strong>. Support for
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    filters may be added at a later date, but no support is planned
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    at this time.</p>
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</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
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<div class="section">
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<h2><a name="journal" id="journal">Programmer's Journal</a></h2>
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    <p>If you are programming Apache 2.0 <code class="module"><a href="../mod/mod_isapi.html">mod_isapi</a></code>
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    modules, you must limit your calls to <code>ServerSupportFunction</code>
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    to the following directives:</p>
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 | 
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    <dl>
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      <dt><code>HSE_REQ_SEND_URL_REDIRECT_RESP</code></dt>
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      <dd>Redirect the user to another location.<br />
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      This must be a fully qualified URL (<em>e.g.</em>
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      <code>http://server/location</code>).</dd>
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      <dt><code>HSE_REQ_SEND_URL</code></dt>
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      <dd>Redirect the user to another location.<br />
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      This cannot be a fully qualified URL, you are not allowed to
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      pass the protocol or a server name (<em>e.g.</em> simply
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      <code>/location</code>).<br />
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      This redirection is handled by the server, not the
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      browser.<br />
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      <div class="warning"><h3>Warning</h3>
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        <p>In their recent documentation, Microsoft appears to have
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        abandoned the distinction between the two
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        <code>HSE_REQ_SEND_URL</code> functions. Apache continues to treat
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        them as two distinct functions with different requirements
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        and behaviors.</p>
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      </div></dd>
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      <dt><code>HSE_REQ_SEND_RESPONSE_HEADER</code></dt>
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      <dd>Apache accepts a response body following the header if it
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      follows the blank line (two consecutive newlines) in the
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      headers string argument. This body cannot contain NULLs,
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      since the headers argument is NULL terminated.</dd>
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      <dt><code>HSE_REQ_DONE_WITH_SESSION</code></dt>
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      <dd>Apache considers this a no-op, since the session will be
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      finished when the ISAPI returns from processing.</dd>
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      <dt><code>HSE_REQ_MAP_URL_TO_PATH</code></dt>
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      <dd>Apache will translate a virtual name to a physical
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      name.</dd>
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      <dt><code>HSE_APPEND_LOG_PARAMETER</code></dt>
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      <dd>
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        This logged message may be captured in any of the following
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        logs:
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        <ul>
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          <li>in the <code>\"%{isapi-parameter}n\"</code> component in a
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          <code class="directive"><a href="../mod/mod_log_config.html#customlog">CustomLog</a></code>
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          directive</li>
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						||
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          <li>in the <code>%q</code> log component with the
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          <code class="directive"><a href="#isapiappendlogtoquery">ISAPIAppendLogToQuery</a></code>
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          <code>On</code> directive</li>
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          <li>in the error log with the <code class="directive"><a href="#isapiappendlogtoerrors">ISAPIAppendLogToErrors</a></code> <code>On</code> directive</li>
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						||
        </ul>
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        <p>The first option, the <code>%{isapi-parameter}n</code> component,
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        is always available and preferred.</p>
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      </dd>
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      <dt><code>HSE_REQ_IS_KEEP_CONN</code></dt>
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      <dd>Will return the negotiated Keep-Alive status.</dd>
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      <dt><code>HSE_REQ_SEND_RESPONSE_HEADER_EX</code></dt>
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      <dd>Will behave as documented, although the <code>fKeepConn</code>
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      flag is ignored.</dd>
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						||
      <dt><code>HSE_REQ_IS_CONNECTED</code></dt>
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      <dd>Will report false if the request has been aborted.</dd>
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						||
    </dl>
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    <p>Apache returns <code>FALSE</code> to any unsupported call to
 | 
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    <code>ServerSupportFunction</code>, and sets the
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    <code>GetLastError</code> value to
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    <code>ERROR_INVALID_PARAMETER</code>.</p>
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    <p><code>ReadClient</code> retrieves the request body exceeding the
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    initial buffer (defined by <code class="directive"><a href="#isapireadaheadbuffer">ISAPIReadAheadBuffer</a></code>). Based on the
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    <code class="directive">ISAPIReadAheadBuffer</code> setting (number of bytes
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    to buffer prior to calling the ISAPI handler) shorter requests are sent
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    complete to the extension when it is invoked. If the request is
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    longer, the ISAPI extension must use <code>ReadClient</code> to
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    retrieve the remaining request body.</p>
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    <p><code>WriteClient</code> is supported, but only with the
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    <code>HSE_IO_SYNC</code> flag or no option flag (value of
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    <code>0</code>). Any other <code>WriteClient</code> request
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    will be rejected with a return value of <code>FALSE</code>, and a
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    <code>GetLastError</code> value of
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    <code>ERROR_INVALID_PARAMETER</code>.</p>
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    <p><code>GetServerVariable</code> is supported, although extended server
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    variables do not exist (as defined by other servers.) All the
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    usual Apache CGI environment variables are available from
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    <code>GetServerVariable</code>, as well as the <code>ALL_HTTP</code>
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						||
    and <code>ALL_RAW</code> values.</p>
 | 
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    <p>Apache httpd 2.0+ <code class="module"><a href="../mod/mod_isapi.html">mod_isapi</a></code> supports additional
 | 
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    features introduced in later versions of the ISAPI specification,
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    as well as limited emulation of async I/O and the
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    <code>TransmitFile</code> semantics. Apache httpd also supports preloading
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    ISAPI .dlls for performance.</p>
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</div>
 | 
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<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
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<div class="directive-section"><h2><a name="ISAPIAppendLogToErrors" id="ISAPIAppendLogToErrors">ISAPIAppendLogToErrors</a> <a name="isapiappendlogtoerrors" id="isapiappendlogtoerrors">Directive</a></h2>
 | 
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<table class="directive">
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<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Record <code>HSE_APPEND_LOG_PARAMETER</code> requests from
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ISAPI extensions to the error log</td></tr>
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<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ISAPIAppendLogToErrors on|off</code></td></tr>
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<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ISAPIAppendLogToErrors off</code></td></tr>
 | 
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<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
 | 
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<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Base</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_isapi</td></tr>
 | 
						||
</table>
 | 
						||
    <p>Record <code>HSE_APPEND_LOG_PARAMETER</code> requests from ISAPI
 | 
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    extensions to the server error log.</p>
 | 
						||
 | 
						||
</div>
 | 
						||
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
 | 
						||
<div class="directive-section"><h2><a name="ISAPIAppendLogToQuery" id="ISAPIAppendLogToQuery">ISAPIAppendLogToQuery</a> <a name="isapiappendlogtoquery" id="isapiappendlogtoquery">Directive</a></h2>
 | 
						||
<table class="directive">
 | 
						||
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Record <code>HSE_APPEND_LOG_PARAMETER</code> requests from
 | 
						||
ISAPI extensions to the query field</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ISAPIAppendLogToQuery on|off</code></td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ISAPIAppendLogToQuery on</code></td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Base</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_isapi</td></tr>
 | 
						||
</table>
 | 
						||
    <p>Record <code>HSE_APPEND_LOG_PARAMETER</code> requests from ISAPI
 | 
						||
    extensions to the query field (appended to the <code class="directive"><a href="../mod/mod_log_config.html#customlog">CustomLog</a></code> <code>%q</code>
 | 
						||
    component).</p>
 | 
						||
 | 
						||
</div>
 | 
						||
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
 | 
						||
<div class="directive-section"><h2><a name="ISAPICacheFile" id="ISAPICacheFile">ISAPICacheFile</a> <a name="isapicachefile" id="isapicachefile">Directive</a></h2>
 | 
						||
<table class="directive">
 | 
						||
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>ISAPI .dll files to be loaded at startup</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ISAPICacheFile <var>file-path</var> [<var>file-path</var>]
 | 
						||
...</code></td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Base</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_isapi</td></tr>
 | 
						||
</table>
 | 
						||
    <p>Specifies a space-separated list of file names to be loaded
 | 
						||
    when the Apache server is launched, and remain loaded until the
 | 
						||
    server is shut down. This directive may be repeated for every
 | 
						||
    ISAPI .dll file desired. The full path name of each file should
 | 
						||
    be specified. If the path name is not absolute, it will be treated
 | 
						||
    relative to <code class="directive"><a href="../mod/core.html#serverroot">ServerRoot</a></code>.</p>
 | 
						||
 | 
						||
</div>
 | 
						||
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
 | 
						||
<div class="directive-section"><h2><a name="ISAPIFakeAsync" id="ISAPIFakeAsync">ISAPIFakeAsync</a> <a name="isapifakeasync" id="isapifakeasync">Directive</a></h2>
 | 
						||
<table class="directive">
 | 
						||
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Fake asynchronous support for ISAPI callbacks</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ISAPIFakeAsync on|off</code></td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ISAPIFakeAsync off</code></td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Base</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_isapi</td></tr>
 | 
						||
</table>
 | 
						||
    <p>While set to on, asynchronous support for ISAPI callbacks is
 | 
						||
    simulated.</p>
 | 
						||
 | 
						||
</div>
 | 
						||
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
 | 
						||
<div class="directive-section"><h2><a name="ISAPILogNotSupported" id="ISAPILogNotSupported">ISAPILogNotSupported</a> <a name="isapilognotsupported" id="isapilognotsupported">Directive</a></h2>
 | 
						||
<table class="directive">
 | 
						||
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Log unsupported feature requests from ISAPI
 | 
						||
extensions</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ISAPILogNotSupported on|off</code></td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ISAPILogNotSupported off</code></td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Base</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_isapi</td></tr>
 | 
						||
</table>
 | 
						||
    <p>Logs all requests for unsupported features from ISAPI
 | 
						||
    extensions in the server error log. This may help administrators
 | 
						||
    to track down problems. Once set to on and all desired ISAPI modules
 | 
						||
    are functioning, it should be set back to off.</p>
 | 
						||
 | 
						||
</div>
 | 
						||
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
 | 
						||
<div class="directive-section"><h2><a name="ISAPIReadAheadBuffer" id="ISAPIReadAheadBuffer">ISAPIReadAheadBuffer</a> <a name="isapireadaheadbuffer" id="isapireadaheadbuffer">Directive</a></h2>
 | 
						||
<table class="directive">
 | 
						||
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Size of the Read Ahead Buffer sent to ISAPI
 | 
						||
extensions</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ISAPIReadAheadBuffer <var>size</var></code></td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ISAPIReadAheadBuffer 49152</code></td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>FileInfo</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Base</td></tr>
 | 
						||
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_isapi</td></tr>
 | 
						||
</table>
 | 
						||
    <p>Defines the maximum size of the Read Ahead Buffer sent to
 | 
						||
    ISAPI extensions when they are initially invoked. All remaining
 | 
						||
    data must be retrieved using the <code>ReadClient</code> callback; some
 | 
						||
    ISAPI extensions may not support the <code>ReadClient</code> function.
 | 
						||
    Refer questions to the ISAPI extension's author.</p>
 | 
						||
 | 
						||
</div>
 | 
						||
</div>
 | 
						||
<div class="bottomlang">
 | 
						||
<p><span>Available Languages: </span><a href="../en/mod/mod_isapi.html" title="English"> en </a> |
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						||
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 | 
						||
</div><div id="footer">
 | 
						||
<p class="apache">Copyright 2012 The Apache Software Foundation.<br />Licensed under the <a href="http://www.apache.org/licenses/LICENSE-2.0">Apache License, Version 2.0</a>.</p>
 | 
						||
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