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<div id="preamble"><h1>Apache Module mod_proxy_fdpass</h1>
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<table class="module"><tr><th><a href="module-dict.html#Description">Description:</a></th><td>fdpass external process support module for
<code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code></td></tr>
<tr><th><a href="module-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="module-dict.html#ModuleIdentifier">Module Identifier:</a></th><td>proxy_fdpass_module</td></tr>
<tr><th><a href="module-dict.html#SourceFile">Source File:</a></th><td>mod_proxy_fdpass.c</td></tr>
<tr><th><a href="module-dict.html#Compatibility">Compatibility:</a></th><td>Available for unix in version 2.3 and later</td></tr></table>
<h3>Summary</h3>

    <p>This module <em>requires</em> the service of <code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code>. It provides support for the passing the socket of the
    client to another process.</p>

    <p><code>mod_proxy_fdpass</code> uses the ability of AF_UNIX domain
    sockets to <a href="http://www.freebsd.org/cgi/man.cgi?query=recv">pass an
    open file descriptor</a> to allow another process to finish handling a request.
    </p>

    <p>The module has a <code>proxy_fdpass_flusher</code> provider interface,
    which allows another module to optionally send the response headers, or even
    the start of the response body.  The default <code>flush</code> provider
    disables keep-alive, and sends the response headers, letting the external
    process just send a response body.
    </p>
    
    <p>In order to use another provider, you have to set the <code>flusher</code>
    parameter in the <code class="directive"><a href="../mod/mod_proxy.html#proxypass">ProxyPass</a></code> directive.
    </p>

    <p>At this time the only data passed to the external process is the client
    socket. To receive a client socket, call recvfrom with an allocated
    <a href="http://www.kernel.org/doc/man-pages/online/pages/man3/cmsg.3.html"><code>struct cmsghdr</code></a>. Future versions of this module may include
    more data after the client socket, but this is not implemented at this time.
    </p>
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<div id="quickview"><a href="https://www.apache.org/foundation/contributing.html" class="badge"><img src="https://www.apache.org/images/SupportApache-small.png" alt="Support Apache!" /></a><h3 class="directives">Directives</h3>
<p>This module provides no
            directives.</p>
<h3>Bugfix checklist</h3><ul class="seealso"><li><a href="https://www.apache.org/dist/httpd/CHANGES_2.4">httpd changelog</a></li><li><a href="https://bz.apache.org/bugzilla/buglist.cgi?bug_status=__open__&amp;list_id=144532&amp;product=Apache%20httpd-2&amp;query_format=specific&amp;order=changeddate%20DESC%2Cpriority%2Cbug_severity&amp;component=mod_proxy_fdpass">Known issues</a></li><li><a href="https://bz.apache.org/bugzilla/enter_bug.cgi?product=Apache%20httpd-2&amp;component=mod_proxy_fdpass">Report a bug</a></li></ul><h3>See also</h3>
<ul class="seealso">
<li><code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code></li>
<li><a href="#comments_section">Comments</a></li></ul></div>

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