1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>basic_stream::connect (7 of 10 overloads)</title> 5<link rel="stylesheet" href="../../../../../../../../doc/src/boostbook.css" type="text/css"> 6<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> 7<link rel="home" href="../../../../index.html" title="Chapter 1. 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The underlying socket is automatically opened if needed. 49 An automatically opened socket is not returned to the closed state upon 50 failure. The algorithm, known as a <span class="emphasis"><em>composed operation</em></span>, 51 is implemented in terms of calls to the underlying socket's <code class="computeroutput"><span class="identifier">connect</span></code> function. 52 </p> 53<h7><a name="beast.ref.boost__beast__basic_stream.connect.overload7.h2"></a> 54 <span class="phrase"><a name="beast.ref.boost__beast__basic_stream.connect.overload7.parameters"></a></span><a class="link" href="overload7.html#beast.ref.boost__beast__basic_stream.connect.overload7.parameters">Parameters</a> 55 </h7><div class="informaltable"><table class="table"> 56<colgroup> 57<col> 58<col> 59</colgroup> 60<thead><tr> 61<th> 62 <p> 63 Name 64 </p> 65 </th> 66<th> 67 <p> 68 Description 69 </p> 70 </th> 71</tr></thead> 72<tbody> 73<tr> 74<td> 75 <p> 76 <code class="computeroutput"><span class="identifier">endpoints</span></code> 77 </p> 78 </td> 79<td> 80 <p> 81 A sequence of endpoints. 82 </p> 83 </td> 84</tr> 85<tr> 86<td> 87 <p> 88 <code class="computeroutput"><span class="identifier">connect_condition</span></code> 89 </p> 90 </td> 91<td> 92 <p> 93 A function object that is called prior to each connection attempt. 94 The signature of the function object must be: 95 </p> 96<pre xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="table-programlisting"><span class="keyword">bool</span> <span class="identifier">connect_condition</span><span class="special">(</span> 97 <span class="identifier">error_code</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">ec</span><span class="special">,</span> 98 <span class="keyword">typename</span> <span class="identifier">Protocol</span><span class="special">::</span><span class="identifier">endpoint</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">next</span><span class="special">);</span> 99</pre> 100 <p> 101 The <code class="computeroutput"><span class="identifier">ec</span></code> parameter 102 contains the result from the most recent connect operation. 103 Before the first connection attempt, <code class="computeroutput"><span class="identifier">ec</span></code> 104 is always set to indicate success. The <code class="computeroutput"><span class="identifier">next</span></code> 105 parameter is the next endpoint to be tried. The function object 106 should return true if the next endpoint should be tried, and 107 false if it should be skipped. 108 </p> 109 </td> 110</tr> 111</tbody> 112</table></div> 113<h7><a name="beast.ref.boost__beast__basic_stream.connect.overload7.h3"></a> 114 <span class="phrase"><a name="beast.ref.boost__beast__basic_stream.connect.overload7.return_value"></a></span><a class="link" href="overload7.html#beast.ref.boost__beast__basic_stream.connect.overload7.return_value">Return 115 Value</a> 116 </h7><p> 117 The successfully connected endpoint. 118 </p> 119<h7><a name="beast.ref.boost__beast__basic_stream.connect.overload7.h4"></a> 120 <span class="phrase"><a name="beast.ref.boost__beast__basic_stream.connect.overload7.exceptions"></a></span><a class="link" href="overload7.html#beast.ref.boost__beast__basic_stream.connect.overload7.exceptions">Exceptions</a> 121 </h7><div class="informaltable"><table class="table"> 122<colgroup> 123<col> 124<col> 125</colgroup> 126<thead><tr> 127<th> 128 <p> 129 Type 130 </p> 131 </th> 132<th> 133 <p> 134 Thrown On 135 </p> 136 </th> 137</tr></thead> 138<tbody><tr> 139<td> 140 <p> 141 <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">system</span><span class="special">::</span><span class="identifier">system_error</span></code> 142 </p> 143 </td> 144<td> 145 <p> 146 Thrown on failure. If the sequence is empty, the associated 147 error code is <code class="computeroutput"><span class="identifier">net</span><span class="special">::</span><span class="identifier">error</span><span class="special">::</span><span class="identifier">not_found</span></code>. 148 Otherwise, contains the error from the last connection attempt. 149 </p> 150 </td> 151</tr></tbody> 152</table></div> 153</div> 154<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 155<td align="left"></td> 156<td align="right"><div class="copyright-footer">Copyright © 2016-2019 Vinnie 157 Falco<p> 158 Distributed under the Boost Software License, Version 1.0. (See accompanying 159 file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>) 160 </p> 161</div></td> 162</tr></table> 163<hr> 164<div class="spirit-nav"> 165<a accesskey="p" href="overload6.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../connect.html"><img src="../../../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../../../index.html"><img src="../../../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="overload8.html"><img src="../../../../../../../../doc/src/images/next.png" alt="Next"></a> 166</div> 167</body> 168</html> 169
