1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>websocket::stream::read (2 of 2 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 46 one of the following is true: 47 </p> 48<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> 49<li class="listitem"> 50 A complete message is received. 51 </li> 52<li class="listitem"> 53 A close frame is received. In this case the error indicated by the 54 function will be <a class="link" href="../../boost__beast__websocket__error.html" title="websocket::error"><code class="computeroutput"><span class="identifier">error</span><span class="special">::</span><span class="identifier">closed</span></code></a>. 55 </li> 56<li class="listitem"> 57 An error occurs. 58 </li> 59</ul></div> 60<p> 61 The algorithm, known as a <span class="emphasis"><em>composed operation</em></span>, is 62 implemented in terms of calls to the next layer's <code class="computeroutput"><span class="identifier">read_some</span></code> 63 and <code class="computeroutput"><span class="identifier">write_some</span></code> functions. 64 Received message data is appended to the buffer. The functions <a class="link" href="../got_binary.html" title="websocket::stream::got_binary"><code class="computeroutput"><span class="identifier">got_binary</span></code></a> and <a class="link" href="../got_text.html" title="websocket::stream::got_text"><code class="computeroutput"><span class="identifier">got_text</span></code></a> may be used to query 65 the stream and determine the type of the last received message. Until 66 the call returns, the implementation will read incoming control frames 67 and handle them automatically as follows: 68 </p> 69<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> 70<li class="listitem"> 71 The <a class="link" href="../control_callback/overload1.html" title="websocket::stream::control_callback (1 of 2 overloads)"><code class="computeroutput"><span class="identifier">control_callback</span></code></a> will be 72 invoked for each control frame. 73 </li> 74<li class="listitem"> 75 For each received ping frame, a pong frame will be automatically 76 sent. 77 </li> 78<li class="listitem"> 79 If a close frame is received, the WebSocket closing handshake is 80 performed. In this case, when the function returns, the error <a class="link" href="../../boost__beast__websocket__error.html" title="websocket::error"><code class="computeroutput"><span class="identifier">error</span><span class="special">::</span><span class="identifier">closed</span></code></a> will be indicated. 81 </li> 82</ul></div> 83<h7><a name="beast.ref.boost__beast__websocket__stream.read.overload2.h2"></a> 84 <span class="phrase"><a name="beast.ref.boost__beast__websocket__stream.read.overload2.return_value"></a></span><a class="link" href="overload2.html#beast.ref.boost__beast__websocket__stream.read.overload2.return_value">Return 85 Value</a> 86 </h7><p> 87 The number of message payload bytes appended to the buffer. 88 </p> 89<h7><a name="beast.ref.boost__beast__websocket__stream.read.overload2.h3"></a> 90 <span class="phrase"><a name="beast.ref.boost__beast__websocket__stream.read.overload2.parameters"></a></span><a class="link" href="overload2.html#beast.ref.boost__beast__websocket__stream.read.overload2.parameters">Parameters</a> 91 </h7><div class="informaltable"><table class="table"> 92<colgroup> 93<col> 94<col> 95</colgroup> 96<thead><tr> 97<th> 98 <p> 99 Name 100 </p> 101 </th> 102<th> 103 <p> 104 Description 105 </p> 106 </th> 107</tr></thead> 108<tbody> 109<tr> 110<td> 111 <p> 112 <code class="computeroutput"><span class="identifier">buffer</span></code> 113 </p> 114 </td> 115<td> 116 <p> 117 A dynamic buffer to append message data to. 118 </p> 119 </td> 120</tr> 121<tr> 122<td> 123 <p> 124 <code class="computeroutput"><span class="identifier">ec</span></code> 125 </p> 126 </td> 127<td> 128 <p> 129 Set to indicate what error occurred, if any. 130 </p> 131 </td> 132</tr> 133</tbody> 134</table></div> 135</div> 136<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 137<td align="left"></td> 138<td align="right"><div class="copyright-footer">Copyright © 2016-2019 Vinnie 139 Falco<p> 140 Distributed under the Boost Software License, Version 1.0. (See accompanying 141 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>) 142 </p> 143</div></td> 144</tr></table> 145<hr> 146<div class="spirit-nav"> 147<a accesskey="p" href="overload1.html"><img src="../../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../read.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="../async_read.html"><img src="../../../../../../../../doc/src/images/next.png" alt="Next"></a> 148</div> 149</body> 150</html> 151
