1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>websocket::stream::handshake (3 of 4 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 call blocks until one of the following conditions 49 is true: 50 </p> 51<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> 52<li class="listitem"> 53 The request is sent and the response is received. 54 </li> 55<li class="listitem"> 56 An error occurs. 57 </li> 58</ul></div> 59<p> 60 The algorithm, known as a <span class="emphasis"><em>composed operation</em></span>, is 61 implemented in terms of calls to the next layer's <code class="computeroutput"><span class="identifier">read_some</span></code> 62 and <code class="computeroutput"><span class="identifier">write_some</span></code> functions. 63 The handshake is successful if the received HTTP response indicates the 64 upgrade was accepted by the server, represented by a <a href="https://tools.ietf.org/html/rfc7230#section-3.1.2" target="_top">status-code</a> 65 of <a class="link" href="../../boost__beast__http__status.html" title="http::status"><code class="computeroutput"><span class="identifier">beast</span><span class="special">::</span><span class="identifier">http</span><span class="special">::</span><span class="identifier">status</span><span class="special">::</span><span class="identifier">switching_protocols</span></code></a>. 66 </p> 67<h7><a name="beast.ref.boost__beast__websocket__stream.handshake.overload3.h2"></a> 68 <span class="phrase"><a name="beast.ref.boost__beast__websocket__stream.handshake.overload3.parameters"></a></span><a class="link" href="overload3.html#beast.ref.boost__beast__websocket__stream.handshake.overload3.parameters">Parameters</a> 69 </h7><div class="informaltable"><table class="table"> 70<colgroup> 71<col> 72<col> 73</colgroup> 74<thead><tr> 75<th> 76 <p> 77 Name 78 </p> 79 </th> 80<th> 81 <p> 82 Description 83 </p> 84 </th> 85</tr></thead> 86<tbody> 87<tr> 88<td> 89 <p> 90 <code class="computeroutput"><span class="identifier">host</span></code> 91 </p> 92 </td> 93<td> 94 <p> 95 The name of the remote host. This is required by the HTTP protocol 96 to set the "Host" header field. 97 </p> 98 </td> 99</tr> 100<tr> 101<td> 102 <p> 103 <code class="computeroutput"><span class="identifier">target</span></code> 104 </p> 105 </td> 106<td> 107 <p> 108 The request-target, in origin-form. The server may use the 109 target to distinguish different services on the same listening 110 port. 111 </p> 112 </td> 113</tr> 114<tr> 115<td> 116 <p> 117 <code class="computeroutput"><span class="identifier">ec</span></code> 118 </p> 119 </td> 120<td> 121 <p> 122 Set to indicate what error occurred, if any. 123 </p> 124 </td> 125</tr> 126</tbody> 127</table></div> 128<h7><a name="beast.ref.boost__beast__websocket__stream.handshake.overload3.h3"></a> 129 <span class="phrase"><a name="beast.ref.boost__beast__websocket__stream.handshake.overload3.example"></a></span><a class="link" href="overload3.html#beast.ref.boost__beast__websocket__stream.handshake.overload3.example">Example</a> 130 </h7><pre class="programlisting"><span class="identifier">error_code</span> <span class="identifier">ec</span><span class="special">;</span> 131<span class="identifier">ws</span><span class="special">.</span><span class="identifier">handshake</span><span class="special">(</span><span class="string">"localhost"</span><span class="special">,</span> <span class="string">"/"</span><span class="special">,</span> <span class="identifier">ec</span><span class="special">);</span> 132</pre> 133<h7><a name="beast.ref.boost__beast__websocket__stream.handshake.overload3.h4"></a> 134 <span class="phrase"><a name="beast.ref.boost__beast__websocket__stream.handshake.overload3.see_also"></a></span><a class="link" href="overload3.html#beast.ref.boost__beast__websocket__stream.handshake.overload3.see_also">See 135 Also</a> 136 </h7><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> 137<li class="listitem"> 138 <a href="https://tools.ietf.org/html/rfc6455#section-4.1" target="_top">Websocket 139 Opening Handshake Client Requirements (RFC6455)</a> 140 </li> 141<li class="listitem"> 142 <a href="https://tools.ietf.org/html/rfc7230#section-5.4" target="_top">Host 143 field (RFC7230)</a> 144 </li> 145<li class="listitem"> 146 <a href="https://tools.ietf.org/html/rfc7230#section-3.1.1" target="_top">request-target 147 (RFC7230)</a> 148 </li> 149<li class="listitem"> 150 <a href="https://tools.ietf.org/html/rfc7230#section-5.3.1" target="_top">origin-form 151 (RFC7230)</a> 152 </li> 153</ul></div> 154</div> 155<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 156<td align="left"></td> 157<td align="right"><div class="copyright-footer">Copyright © 2016-2019 Vinnie 158 Falco<p> 159 Distributed under the Boost Software License, Version 1.0. (See accompanying 160 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>) 161 </p> 162</div></td> 163</tr></table> 164<hr> 165<div class="spirit-nav"> 166<a accesskey="p" href="overload2.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../handshake.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="overload4.html"><img src="../../../../../../../../doc/src/images/next.png" alt="Next"></a> 167</div> 168</body> 169</html> 170