693 lines
22 KiB
HTML
693 lines
22 KiB
HTML
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<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
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<html>
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<head>
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<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
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<meta name="Copyright" content="Copyright (c) 2006 by IBM Corporation">
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<title>accept_and_recv()--Wait for Connection Request and Receive the First
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Message That Was Sent</title>
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<!-- Begin Header Records ========================================== -->
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<!-- All rights reserved. Licensed Materials Property of IBM -->
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<!-- US Government Users Restricted Rights -->
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<!-- Use, duplication or disclosure restricted by -->
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<!-- GSA ADP Schedule Contract with IBM Corp. -->
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<!-- Change History: -->
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<!-- YYMMDD USERID Change description -->
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<!-- Direct1 SCRIPT J converted by B2H R4.1 (346) (CMS) by V2KEA304 -->
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<!-- at RCHVMW2 on 17 Feb 1999 at 11:05:09 -->
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<!-- Edited by Kersten Feb 02 -->
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<!-- End Header Records -->
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<link rel="stylesheet" type="text/css" href="../rzahg/ic.css">
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</head>
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<body>
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<!--Java sync-link-->
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<script type="text/javascript" language="Javascript" src="../rzahg/synch.js">
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</script>
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<a name="Top_Of_Page"></a>
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<h2>accept_and_recv()--Wait for Connection Request and Receive the First
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Message That Was Sent</h2>
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<div class="box" style="width: 70%;">
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<br>
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BSD 4.3 Syntax<br>
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<pre>
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#include <sys/types.h>
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#include <sys/socket.h>
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int accept_and_recv(int <em>listen_socket_descriptor</em>,
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int *<em>accept_socket_descriptor</em>,
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struct sockaddr *<em>remote_address</em>,
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size_t *<em>remote_address_length</em>,
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struct sockaddr *<em>local_address</em>,
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size_t *<em>local_address_length</em>,
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void *<em>buffer</em>,
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size_t <em>buffer_length</em>)
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</pre>
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<br>
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Service Program Name: QSOSRV1<br>
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<!-- iddvc RMBR -->
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<br>
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Default Public Authority: *USE<br>
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<!-- iddvc RMBR -->
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<br>
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Threadsafe: Yes<br>
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<!-- iddvc RMBR -->
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<br>
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</div>
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<br>
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<div class="box" style="width: 70%;">
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<br>
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<a href="_xopen_source.htm">UNIX 98 Compatible Syntax</a><br>
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<pre>
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#define _XOPEN_SOURCE 520
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#include <sys/socket.h>
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int accept_and_recv(int <em>listen_socket_descriptor</em>,
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int *<em>accept_socket_descriptor</em>,
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struct sockaddr *<em>remote_address</em>,
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socklen_t *<em>remote_address_length</em>,
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struct sockaddr *<em>local_address</em>,
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socklen_t *<em>local_address_length</em>,
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void *<em>buffer</em>,
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size_t <em>buffer_length</em>)
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</pre>
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<br>
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Service Program Name: QSOSRV1<br>
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<!-- iddvc RMBR -->
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<br>
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Default Public Authority: *USE<br>
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<!-- iddvc RMBR -->
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<br>
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Threadsafe: Yes<br>
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<!-- iddvc RMBR -->
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<br>
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</div>
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<p>The <em>accept_and_recv()</em> function is used to wait for an incoming
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connection request, receive the first message from the peer, and return the
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local and remote socket addresses associated with the connection.</p>
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<p><em>accept_and_recv()</em> is used with connection-oriented sockets that
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have an address family of <samp>AF_INET</samp> or <samp>AF_INET6</samp> and a socket type of <samp>SOCK_STREAM</samp>.</p>
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<p>The <em>accept_and_recv()</em> API is a combination of the
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<em>accept()</em>, <em>getsockname()</em>, and <em>recv()</em> socket APIs.
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Socket applications that use these three APIs can obtain improved performance
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by using <em>accept_and_recv()</em>.</p>
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<p> There are two versions of
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the API, as shown above. The base i5/OS<SUP>(TM)</SUP> API uses BSD 4.3 structures and
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syntax. The other uses syntax and structures compatible with the UNIX 98
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programming interface specifications. You can select the UNIX 98 compatible
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interface with the <a href="_xopen_source.htm">_XOPEN_SOURCE</a> macro.</p>
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<br>
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<h3>Parameters</h3>
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<dl>
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<dt><strong>listen_socket_descriptor</strong></dt>
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<dd>(Input) The descriptor of the socket on which to wait. This parameter
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specifies the socket that has issued a successful call to
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<em>listen()</em>.<br>
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<br>
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</dd>
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<dt><strong>accept_socket_descriptor</strong></dt>
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<dd>(Input/Output) A pointer to an integer that specifies the socket descriptor
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on which to accept the incoming connection. This socket must not be bound or
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connected. The use of this parameter lets the application reuse the accepting
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socket.
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<p>If a pointer to a value of -1 is passed in for this parameter, a new
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descriptor in the process's descriptor table will be allocated for incoming
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connection. The socket descriptor for a new connection will be returned to the
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application by this parameter. It is recommended that a value of -1 be used on
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the first call to <em>accept_and_recv()</em>. See the <a href=
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"#USAGE_NOTES">Usage Notes</a> for additional information.</p>
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</dd>
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<dt><strong>remote_address</strong></dt>
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<dd>(Output) A pointer to a buffer of type <strong>struct sockaddr</strong> in
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which the address from which the connection request was received is stored. The
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structure <strong>sockaddr</strong> is defined in
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<strong><sys/socket.h></strong>.
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<p> The BSD 4.3 structure
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is:</p>
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<pre>
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struct sockaddr {
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u_short sa_family;
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char sa_data[14];
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};
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</pre>
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<p>The BSD 4.4/UNIX 98 compatible structure is:</p>
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<pre>
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typedef uchar sa_family_t;
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struct sockaddr {
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uint8_t sa_len;
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sa_family_t sa_family;
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char sa_data[14];
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};
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</pre>
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<p>The BSD 4.4 <em>sa_len</em> field is the length of the address. The <em>sa_family</em> field identifies
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the address family to which the address belongs, and <em>sa_data</em> is the
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address whose format is dependent on the address family.</p>
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<p> <strong>Note:</strong> See
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the usage notes about using different address families with
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<strong>sockaddr_storage</strong>.</p>
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</dd>
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<dt><strong>remote_address_length</strong></dt>
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<dd>(Input/Output) This parameter is a value-result field. The caller passes a
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pointer to the length of the <em>remote_address</em> parameter. On return from
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the call, <em>remote_address_length</em> contains the actual length of the
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address from which the connection request was received.<br>
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<br>
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</dd>
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<dt><strong>local_address</strong></dt>
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<dd>(Output) A pointer to a buffer of type <strong>struct sockaddr</strong> in
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which the local address over which the connection request was received is
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stored. The structure <strong>sockaddr</strong> is defined in
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<strong><sys/socket.h></strong>.
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<p> The BSD 4.3 structure
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is:</p>
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<pre>
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struct sockaddr {
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u_short sa_family;
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char sa_data[14];
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};
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</pre>
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<p>The BSD 4.4/UNIX 98 compatible structure is:</p>
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<pre>
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typedef uchar sa_family_t;
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struct sockaddr {
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uint8_t sa_len;
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sa_family_t sa_family;
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char sa_data[14];
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};
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</pre>
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<p>The BSD 4.4 <em>sa_len</em> field is the length of the address. The <em>sa_family</em> field identifies
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the address family to which the address belongs, and <em>sa_data</em> is the
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address whose format is dependent on the address family.</p>
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<p> <strong>Note:</strong> See
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the usage notes about using different address families with
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<strong>sockaddr_storage</strong>.</p>
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</dd>
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<dt><strong>local_address_length</strong></dt>
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<dd>(Input/Output) This parameter is a value-result field. The caller passes a
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pointer to the length of the <em>local_address</em> parameter. On return from
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the call, <em>local_address_length</em> contains the actual length of the local
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address over which the connection request was received.<br>
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<br>
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</dd>
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<dt><strong>buffer</strong></dt>
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<dd>(Output) The pointer to the buffer in which the data that is to be read is
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stored. If a NULL pointer is passed in for this parameter, the receive
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operation is not performed and the <em>accept_and_recv()</em> function
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completes when the incoming connection is received.<br>
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<br>
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</dd>
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<dt><strong>buffer_length</strong></dt>
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<dd>(Input) The length in bytes of the buffer pointed to by the <em>buffer</em>
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parameter.</dd>
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</dl>
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<br>
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<h3>Authorities</h3>
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<p>If IP over SNA is being used, *CHANGE authority to the APPC device is
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required.</p>
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<br>
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<h3>Return Value</h3>
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<p><em>accept_and_recv()</em> returns an integer. Possible values are:</p>
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<ul>
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<li>-1 (unsuccessful call)<br>
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<br>
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</li>
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<li>n (successful call), where n is the number of bytes received.</li>
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</ul>
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<br>
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<h3>Error Conditions</h3>
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<p>When <em>accept_and_recv()</em> fails, <em>errno</em> can be set to one of
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the following:</p>
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<table cellpadding="5">
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<!-- cols="20 80" -->
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<tr>
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<td align="left" valign="top"><em>[EACCES]</em></td>
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<td align="left" valign="top">Permission denied.
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<p>A connection indication request was received on the socket referenced by the
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<em>listen_socket_descriptor</em> parameter, but the process that issued the
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<em>accept_and_recv()</em> call did not have the appropriate privileges
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required to handle the request. The connection indication request is reset by
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the system.</p>
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</td>
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</tr>
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<tr>
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<td align="left" valign="top"><em>[EBADF]</em></td>
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<td align="left" valign="top">Descriptor not valid.
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<p>Either the <em>listen_socket_descriptor</em> or the descriptor pointed to by
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the <em>accept_socket_descriptor</em> parameter is not a valid socket
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descriptor.</p>
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</td>
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</tr>
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<tr>
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<td align="left" valign="top"><em>[ECONNABORTED]</em></td>
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<td align="left" valign="top">Connection ended abnormally.
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<p>An <em>accept_and_recv()</em> was issued on a socket for which receive
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operations have been disallowed (due to a <em>shutdown()</em> call).</p>
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</td>
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</tr>
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<tr>
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<td align="left" valign="top"><em>[EFAULT]</em></td>
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<td align="left" valign="top">Bad address.
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<p>System detected an address that was not valid while attempting to access the
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<em>accept_socket_descriptor</em>, <em>remote_address</em>,
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<em>remote_address_length</em>, <em>local_address</em>,
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<em>local_address_length</em>, or <em>buffer</em> parameter.</p>
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</td>
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</tr>
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<tr>
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<td align="left" valign="top"><em>[EINTR]</em></td>
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<td align="left" valign="top">Interrupted function call.<br>
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<br>
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</td>
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</tr>
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<tr>
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<td align="left" valign="top"><em>[EINVAL]</em></td>
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<td align="left" valign="top">Parameter not valid.
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<p>This error code indicates one of the following:</p>
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<ul>
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<li>A <em>listen()</em> has not been issued against the socket referenced by
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the <em>listen_socket_descriptor</em> parameter.<br>
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<br>
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</li>
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<li>The socket referenced by the <em>accept_socket_descriptor</em> parameter
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has been bound to a local address.<br>
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<br>
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</li>
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<li>The <em>accept_socket_descriptor</em> does not have the same address family
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and socket type as the <em>listen_socket_descriptor</em>.<br>
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<br>
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</li>
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<li>The <em>accept_socket_descriptor</em> parameter is set to a value that is
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less than -1.<br>
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</li>
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</ul>
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</td>
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</tr>
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<tr>
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<td align="left" valign="top"><em>[EIO]</em></td>
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<td align="left" valign="top">Input/output error.<br>
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<br>
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</td>
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</tr>
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<tr>
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<td align="left" valign="top"><em>[EISCONN]</em></td>
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<td align="left" valign="top">A connection has already been established.<br>
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<br>
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</td>
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</tr>
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<tr>
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|
|
<td align="left" valign="top"><em>[EMFILE]</em></td>
|
||
|
|
<td align="left" valign="top">Too many descriptions for this process.<br>
|
||
|
|
<br>
|
||
|
|
</td>
|
||
|
|
</tr>
|
||
|
|
|
||
|
|
<tr>
|
||
|
|
<td align="left" valign="top"><em>[ENFILE]</em></td>
|
||
|
|
<td align="left" valign="top">Too many descriptions in system.<br>
|
||
|
|
<br>
|
||
|
|
</td>
|
||
|
|
</tr>
|
||
|
|
|
||
|
|
<tr>
|
||
|
|
<td align="left" valign="top"><em>[ENOBUFS]</em></td>
|
||
|
|
<td align="left" valign="top">There is not enough buffer space for the
|
||
|
|
requested operation.<br>
|
||
|
|
<br>
|
||
|
|
</td>
|
||
|
|
</tr>
|
||
|
|
|
||
|
|
<tr>
|
||
|
|
<td align="left" valign="top"><em>[ENOTSOCK]</em></td>
|
||
|
|
<td align="left" valign="top">The specified descriptor does not reference a
|
||
|
|
socket.
|
||
|
|
|
||
|
|
<p>Either the <em>listen_socket_descriptor</em> or the descriptor pointed to by
|
||
|
|
the <em>accept_socket_descriptor</em> parameter is not a valid socket
|
||
|
|
descriptor.</p>
|
||
|
|
</td>
|
||
|
|
</tr>
|
||
|
|
|
||
|
|
<tr>
|
||
|
|
<td align="left" valign="top"><em>[EOPNOTSUPP]</em></td>
|
||
|
|
<td align="left" valign="top">Operation not supported.
|
||
|
|
|
||
|
|
<p>This error code indicates one of the following:</p>
|
||
|
|
|
||
|
|
<ul>
|
||
|
|
<li>The <em>listen_socket_descriptor</em> parameter references a socket that
|
||
|
|
does not support the <em>accept_and_recv()</em> function. The
|
||
|
|
<em>accept_and_recv()</em> function is only valid on sockets that have an
|
||
|
|
address family of <samp>AF_INET</samp> or <samp>AF_INET6</samp> and a socket type of <samp>SOCK_STREAM</samp>.<br>
|
||
|
|
<br>
|
||
|
|
</li>
|
||
|
|
|
||
|
|
<li>The <samp>O_NONBLOCK</samp> option is set for the
|
||
|
|
<em>listen_socket_descriptor</em> or the descriptor pointed to by the
|
||
|
|
<em>accept_socket_descriptor</em> parameter. Non-blocking is not supported for
|
||
|
|
<em>accept_and_recv()</em>.<br>
|
||
|
|
</li>
|
||
|
|
</ul>
|
||
|
|
</td>
|
||
|
|
</tr>
|
||
|
|
|
||
|
|
<tr>
|
||
|
|
<td align="left" valign="top"><em>[EUNATCH]</em></td>
|
||
|
|
<td align="left" valign="top">The protocol required to support the specified
|
||
|
|
address family is not available at this time.<br>
|
||
|
|
<br>
|
||
|
|
</td>
|
||
|
|
</tr>
|
||
|
|
|
||
|
|
<tr>
|
||
|
|
<td align="left" valign="top"><em>[EUNKNOWN]</em></td>
|
||
|
|
<td align="left" valign="top">Unknown system state.</td>
|
||
|
|
</tr>
|
||
|
|
</table>
|
||
|
|
|
||
|
|
<br>
|
||
|
|
<br>
|
||
|
|
<h3>Error Messages</h3>
|
||
|
|
|
||
|
|
<table cellpadding="5" width="100%">
|
||
|
|
<!-- cols="15 85" -->
|
||
|
|
<tr>
|
||
|
|
<th align="left" valign="top">Message ID</th>
|
||
|
|
<th align="left" valign="top">Error Message Text</th>
|
||
|
|
</tr>
|
||
|
|
|
||
|
|
<tr>
|
||
|
|
<td width="15%" valign="top">CPE3418 E</td>
|
||
|
|
<td width="85%" valign="top">Possible APAR condition or hardware failure.</td>
|
||
|
|
</tr>
|
||
|
|
|
||
|
|
<tr>
|
||
|
|
<td align="left" valign="top">CPF9872 E</td>
|
||
|
|
<td align="left" valign="top">Program or service program &1 in library
|
||
|
|
&2 ended. Reason code &3.</td>
|
||
|
|
</tr>
|
||
|
|
|
||
|
|
<tr>
|
||
|
|
<td align="left" valign="top">CPFA081 E</td>
|
||
|
|
<td align="left" valign="top">Unable to set return value or error code.</td>
|
||
|
|
</tr>
|
||
|
|
</table>
|
||
|
|
|
||
|
|
<br>
|
||
|
|
<br>
|
||
|
|
<h3><a name="USAGE_NOTES">Usage Notes</a></h3>
|
||
|
|
|
||
|
|
<ol>
|
||
|
|
<li>The <em>accept_and_recv()</em> function is only valid on sockets that have
|
||
|
|
an address family of AF_INET or
|
||
|
|
AF_INET6 and a socket type of
|
||
|
|
SOCK_STREAM. If the <em>listen_socket_descriptor</em> does not have the correct
|
||
|
|
address family and socket type, -1 is returned and the <em>errno</em> value is
|
||
|
|
set to EOPNOTSUPP.<br>
|
||
|
|
<br>
|
||
|
|
</li>
|
||
|
|
|
||
|
|
<li>Non-blocking mode is not supported for this function. If O_NONBLOCK is set
|
||
|
|
on the <em>listen_socket_descriptor</em> parameter or on the descriptor pointed
|
||
|
|
to by the <em>accept_socket_descriptor</em> parameter, -1 is returned and the
|
||
|
|
<em>errno</em> value is set to EOPNOTSUPP.<br>
|
||
|
|
<br>
|
||
|
|
</li>
|
||
|
|
|
||
|
|
<li>If the <em>remote_address</em> parameter is set to a NULL pointer, the
|
||
|
|
address from which the connection request was received is not returned. If the
|
||
|
|
length of the remote address to be returned exceeds the length that was
|
||
|
|
specified by the <em>remote_address_length</em> parameter, the returned address
|
||
|
|
will be truncated.<br>
|
||
|
|
<br>
|
||
|
|
</li>
|
||
|
|
|
||
|
|
<li>If the <em>local_address</em> parameter is set to a NULL pointer, the local
|
||
|
|
address to which the socket is bound is not returned. If the length of the
|
||
|
|
local address to be returned exceeds the length that was specified by the
|
||
|
|
<em>local_address_length</em> parameter, the returned address will be
|
||
|
|
truncated.<br>
|
||
|
|
<br>
|
||
|
|
</li>
|
||
|
|
|
||
|
|
<li>If the <em>buffer</em> parameter is set to a NULL pointer or the
|
||
|
|
<em>buffer_length</em> parameter is set to value of 0, the receive operation is
|
||
|
|
not performed and the <em>accept_and_recv()</em> function completes when the
|
||
|
|
incoming connection is received.<br>
|
||
|
|
<br>
|
||
|
|
</li>
|
||
|
|
|
||
|
|
<li>If a pointer to a value of -1 is passed in for the
|
||
|
|
<em>accept_socket_descriptor</em> parameter, the following attributes are
|
||
|
|
inherited by the socket descriptor that is returned by the
|
||
|
|
<em>accept_and_recv()</em> call:
|
||
|
|
|
||
|
|
<ul>
|
||
|
|
<li>All socket options with a level of SOL_SOCKET.<br>
|
||
|
|
<br>
|
||
|
|
</li>
|
||
|
|
|
||
|
|
<li>The status flags:
|
||
|
|
|
||
|
|
<ul>
|
||
|
|
<li>Asynchronous flag (set or reset either by the <em>ioctl()</em> call with
|
||
|
|
the FIOASYNC request or by the <em>fcntl()</em> call with the F_SETFL command
|
||
|
|
and the status flag set to FASYNC).</li>
|
||
|
|
</ul>
|
||
|
|
|
||
|
|
<br>
|
||
|
|
<br>
|
||
|
|
</li>
|
||
|
|
|
||
|
|
<li>The process ID or process group ID that is to receive SIGIO or SIGURG
|
||
|
|
signals (set or reset by either the <em>ioctl()</em> call with the FIOSETOWN or
|
||
|
|
the SIOCSPGRP request, or by the <em>fcntl()</em> call with the F_SETOWN
|
||
|
|
command).</li>
|
||
|
|
</ul>
|
||
|
|
|
||
|
|
<br>
|
||
|
|
<br>
|
||
|
|
</li>
|
||
|
|
|
||
|
|
<li>The <em>accept_and_recv()</em> function allows an application to reuse an
|
||
|
|
existing socket descriptor. If a socket descriptor is specified for the
|
||
|
|
<em>accept_socket_descriptor</em> parameter, it must not be bound or connected
|
||
|
|
and it must have the same address family and socket type as the
|
||
|
|
<em>listen_socket_descriptor</em>. The socket descriptor that is passed in for
|
||
|
|
the <em>accept_socket_descriptor</em> parameter can be obtained by either
|
||
|
|
calling <em>socket()</em> or by specifying the SF_REUSE flag on the
|
||
|
|
<em>flags</em> parameter of the <em>send_file()</em> function.
|
||
|
|
|
||
|
|
<p>If an application specifies a pointer to an unbound and unconnected socket
|
||
|
|
descriptor for the <em>accept_socket_descriptor</em> parameter that is the same
|
||
|
|
address family and socket type as the <em>listen_socket_descriptor</em>, the
|
||
|
|
<em>accept_and_recv()</em> function will try to use the
|
||
|
|
<em>accept_socket_descriptor</em> for the incoming connection. If the
|
||
|
|
<em>accept_socket_descriptor</em> cannot be used for the incoming connection,
|
||
|
|
the descriptor for that socket will be closed and a new socket will be created
|
||
|
|
for the incoming connection. The new socket may have a different descriptor
|
||
|
|
number associated with it. This means that the value that is returned by the
|
||
|
|
<em>accept_socket_descriptor</em> parameter may not be the same value that was
|
||
|
|
specified by the application when the <em>accept_and_recv()</em> function was
|
||
|
|
called.</p>
|
||
|
|
|
||
|
|
<p>The ability to reuse an existing socket is not supported on all platforms.
|
||
|
|
Therefore, it is recommended that a pointer to a value of -1 be passed in for
|
||
|
|
the <em>accept_socket_descriptor</em> parameter. If socket reuse is not
|
||
|
|
supported and the <em>send_file()</em> API is called with the <em>flags</em>
|
||
|
|
parameter set to SF_REUSE, the socket connection will be closed and the socket
|
||
|
|
descriptor will be set to -1 by the <em>send_file()</em> API. If socket reuse
|
||
|
|
is supported, then the connection will be closed and the socket descriptor will
|
||
|
|
be reset so that it can be used again. Regardless of whether socket reuse is
|
||
|
|
supported or not, the application can pass its socket descriptor variable into
|
||
|
|
the <em>accept_and_recv()</em> function as the
|
||
|
|
<em>accept_socket_descriptor</em> parameter.</p>
|
||
|
|
</li>
|
||
|
|
|
||
|
|
<li>The structure
|
||
|
|
<strong>sockaddr</strong> is a generic structure used for any address family
|
||
|
|
but it is only 16 bytes long. The actual address returned for some address
|
||
|
|
families may be much larger. You should declare storage for the address with
|
||
|
|
the structure <strong>sockaddr_storage</strong>. This structure is large enough
|
||
|
|
and aligned for any protocol-specific structure. It may then be cast as
|
||
|
|
<strong>sockaddr</strong> structure for use on the APIs. The <em>ss_family</em>
|
||
|
|
field of the <strong>sockaddr_storage</strong> will always align with the
|
||
|
|
family field of any protocol-specific structure.
|
||
|
|
|
||
|
|
<p>The BSD 4.3 structure is:</p>
|
||
|
|
|
||
|
|
<pre>
|
||
|
|
#define _SS_MAXSIZE 304
|
||
|
|
#define _SS_ALIGNSIZE (sizeof (char*))
|
||
|
|
#define _SS_PAD1SIZE (_SS_ALIGNSIZE - sizeof(sa_family_t))
|
||
|
|
#define _SS_PAD2SIZE (_SS_MAXSIZE - (sizeof(sa_family_t)+
|
||
|
|
_SS_PAD1SIZE + _SS_ALIGNSIZE))
|
||
|
|
|
||
|
|
struct sockaddr_storage {
|
||
|
|
sa_family_t ss_family;
|
||
|
|
char _ss_pad1[_SS_PAD1SIZE];
|
||
|
|
char* _ss_align;
|
||
|
|
char _ss_pad2[_SS_PAD2SIZE];
|
||
|
|
};
|
||
|
|
</pre>
|
||
|
|
|
||
|
|
<p>The BSD 4.4/UNIX 98 compatible structure is:</p>
|
||
|
|
|
||
|
|
<pre>
|
||
|
|
#define _SS_MAXSIZE 304
|
||
|
|
#define _SS_ALIGNSIZE (sizeof (char*))
|
||
|
|
#define _SS_PAD1SIZE (_SS_ALIGNSIZE - (sizeof(uint8_t) + sizeof(sa_family_t)))
|
||
|
|
#define _SS_PAD2SIZE (_SS_MAXSIZE - (sizeof(uint8_t) + sizeof(sa_family_t)+
|
||
|
|
_SS_PAD1SIZE + _SS_ALIGNSIZE))
|
||
|
|
|
||
|
|
struct sockaddr_storage {
|
||
|
|
uint8_t ss_len;
|
||
|
|
sa_family_t ss_family;
|
||
|
|
char _ss_pad1[_SS_PAD1SIZE];
|
||
|
|
char* _ss_align;
|
||
|
|
char _ss_pad2[_SS_PAD2SIZE];
|
||
|
|
};
|
||
|
|
</pre>
|
||
|
|
|
||
|
|
</li>
|
||
|
|
|
||
|
|
<li>To take full advantage of the performance improvement offered by the
|
||
|
|
<em>accept_and_recv()</em> API, a multiple accept server model needs to be used
|
||
|
|
by the application. In this model the server will do a <em>socket()</em>,
|
||
|
|
<em>bind()</em>, and <em>listen()</em> as currently is done. The server will
|
||
|
|
then give the listening socket to multiple jobs or threads. Each job or thread
|
||
|
|
will then call <em>accept_and_recv()</em> using the same listening socket. When
|
||
|
|
a connection request comes in, only one of the jobs or threads would wake
|
||
|
|
up.<br>
|
||
|
|
<br>
|
||
|
|
</li>
|
||
|
|
|
||
|
|
<li>If a successful <em>Rbind()</em> has been performed on the listening
|
||
|
|
socket, then a new connection is not returned, but rather an inbound connection
|
||
|
|
occurs on the same listening socket. The descriptor number returned is
|
||
|
|
different, but it actually refers to the same connection referred to by the
|
||
|
|
listening socket.</li>
|
||
|
|
|
||
|
|
<li>When you develop in C-based
|
||
|
|
languages and an application is compiled with the _XOPEN_SOURCE macro defined
|
||
|
|
to the value 520 or greater, the <em>accept_and_recv()</em> API is mapped to
|
||
|
|
<em>qso_accept_and_recv98()</em>.</li>
|
||
|
|
</ol>
|
||
|
|
|
||
|
|
<br>
|
||
|
|
|
||
|
|
|
||
|
|
<h3>Related Information</h3>
|
||
|
|
|
||
|
|
<ul>
|
||
|
|
<li><a href=
|
||
|
|
"_xopen_source.htm">_XOPEN_SOURCE</a>--Using _XOPEN_SOURCE for the UNIX 98
|
||
|
|
compatible interface<br>
|
||
|
|
<br>
|
||
|
|
</li>
|
||
|
|
|
||
|
|
<li><a href="accept.htm">accept()</a>--Wait for Connection Request and Make
|
||
|
|
Connection<br>
|
||
|
|
<br>
|
||
|
|
</li>
|
||
|
|
|
||
|
|
<li><a href="gsockn.htm">getsockname()</a>--Retrieve Local Address of
|
||
|
|
Socket<br>
|
||
|
|
<br>
|
||
|
|
</li>
|
||
|
|
|
||
|
|
<li><a href="recv.htm">recv()</a>--Receive Data<br>
|
||
|
|
<br>
|
||
|
|
</li>
|
||
|
|
|
||
|
|
<li><a href="sendfile.htm">send_file()</a>--Send a File over a Socket
|
||
|
|
Connection</li>
|
||
|
|
</ul>
|
||
|
|
|
||
|
|
<br>
|
||
|
|
<hr>
|
||
|
|
API introduced: V4R3
|
||
|
|
|
||
|
|
<hr>
|
||
|
|
<center>
|
||
|
|
<table cellpadding="2" cellspacing="2">
|
||
|
|
<tr align="center">
|
||
|
|
<td valign="middle" align="center"><a href="#Top_Of_Page">Top</a> | <a href=
|
||
|
|
"unix.htm">UNIX-Type APIs</a> | <a href="aplist.htm">APIs by category</a></td>
|
||
|
|
</tr>
|
||
|
|
</table></center>
|
||
|
|
</body>
|
||
|
|
</html>
|
||
|
|
|