1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>websocket::stream::async_write</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. Boost.Beast"> 8<link rel="up" href="../boost__beast__websocket__stream.html" title="websocket::stream"> 9<link rel="prev" href="write/overload2.html" title="websocket::stream::write (2 of 2 overloads)"> 10<link rel="next" href="write_some.html" title="websocket::stream::write_some"> 11</head> 12<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> 13<table cellpadding="2" width="100%"><tr> 14<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../../../../boost.png"></td> 15<td align="center"><a href="../../../../../../../index.html">Home</a></td> 16<td align="center"><a href="../../../../../../../libs/libraries.htm">Libraries</a></td> 17<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td> 18<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td> 19<td align="center"><a href="../../../../../../../more/index.htm">More</a></td> 20</tr></table> 21<hr> 22<div class="spirit-nav"> 23<a accesskey="p" href="write/overload2.html"><img src="../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../boost__beast__websocket__stream.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="write_some.html"><img src="../../../../../../../doc/src/images/next.png" alt="Next"></a> 24</div> 25<div class="section"> 26<div class="titlepage"><div><div><h5 class="title"> 27<a name="beast.ref.boost__beast__websocket__stream.async_write"></a><a class="link" href="async_write.html" title="websocket::stream::async_write">websocket::stream::async_write</a> 28</h5></div></div></div> 29<p> 30 <a class="indexterm" name="idm46057517524592"></a> 31 </p> 32<p> 33 Write a complete message asynchronously. 34 </p> 35<h6> 36<a name="beast.ref.boost__beast__websocket__stream.async_write.h0"></a> 37 <span class="phrase"><a name="beast.ref.boost__beast__websocket__stream.async_write.synopsis"></a></span><a class="link" href="async_write.html#beast.ref.boost__beast__websocket__stream.async_write.synopsis">Synopsis</a> 38 </h6> 39<pre class="programlisting"><span class="keyword">template</span><span class="special"><</span> 40 <span class="keyword">class</span> <a href="../../../../../../../doc/html/boost_asio/reference/ConstBufferSequence.html" target="_top"><span class="emphasis"><em>ConstBufferSequence</em></span></a><span class="special">,</span> 41 <span class="keyword">class</span> <a href="../../../../../../../doc/html/boost_asio/reference/WriteHandler.html" target="_top"><span class="emphasis"><em>WriteHandler</em></span></a> <span class="special">=</span> <span class="identifier">net</span><span class="special">::</span><span class="identifier">default_completion_token_t</span><span class="special"><</span> <a class="link" href="executor_type.html" title="websocket::stream::executor_type">executor_type</a><span class="special">>></span> 42<a href="../../../../../../../doc/html/boost_asio/reference/asynchronous_operations.html#boost_asio.reference.asynchronous_operations.automatic_deduction_of_initiating_function_return_type" target="_top"><span class="emphasis"><em>DEDUCED</em></span></a> 43<span class="identifier">async_write</span><span class="special">(</span> 44 <span class="identifier">ConstBufferSequence</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">buffers</span><span class="special">,</span> 45 <span class="identifier">WriteHandler</span><span class="special">&&</span> <span class="identifier">handler</span> <span class="special">=</span> <span class="identifier">net</span><span class="special">::</span><span class="identifier">default_completion_token_t</span><span class="special"><</span> <a class="link" href="executor_type.html" title="websocket::stream::executor_type">executor_type</a> <span class="special">>{});</span> 46</pre> 47<h6> 48<a name="beast.ref.boost__beast__websocket__stream.async_write.h1"></a> 49 <span class="phrase"><a name="beast.ref.boost__beast__websocket__stream.async_write.description"></a></span><a class="link" href="async_write.html#beast.ref.boost__beast__websocket__stream.async_write.description">Description</a> 50 </h6> 51<p> 52 This function is used to asynchronously write a complete message. This 53 call always returns immediately. The asynchronous operation will continue 54 until one of the following conditions is true: 55 </p> 56<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> 57<li class="listitem"> 58 The complete message is written. 59 </li> 60<li class="listitem"> 61 An error occurs. 62 </li> 63</ul></div> 64<p> 65 The algorithm, known as a <span class="emphasis"><em>composed asynchronous operation</em></span>, 66 is implemented in terms of calls to the next layer's <code class="computeroutput"><span class="identifier">async_write_some</span></code> 67 function. The program must ensure that no other calls to <a class="link" href="write/overload1.html" title="websocket::stream::write (1 of 2 overloads)"><code class="computeroutput"><span class="identifier">write</span></code></a>, <a class="link" href="write_some/overload1.html" title="websocket::stream::write_some (1 of 2 overloads)"><code class="computeroutput"><span class="identifier">write_some</span></code></a>, <a class="link" href="async_write.html" title="websocket::stream::async_write"><code class="computeroutput"><span class="identifier">async_write</span></code></a>, or <a class="link" href="async_write_some.html" title="websocket::stream::async_write_some"><code class="computeroutput"><span class="identifier">async_write_some</span></code></a> are performed 68 until this operation completes. The current setting of the <a class="link" href="binary/overload1.html" title="websocket::stream::binary (1 of 2 overloads)"><code class="computeroutput"><span class="identifier">binary</span></code></a> option controls whether 69 the message opcode is set to text or binary. If the <a class="link" href="auto_fragment/overload1.html" title="websocket::stream::auto_fragment (1 of 2 overloads)"><code class="computeroutput"><span class="identifier">auto_fragment</span></code></a> option is set, the 70 message will be split into one or more frames as necessary. The actual 71 payload contents sent may be transformed as per the WebSocket protocol 72 settings. 73 </p> 74<h6> 75<a name="beast.ref.boost__beast__websocket__stream.async_write.h2"></a> 76 <span class="phrase"><a name="beast.ref.boost__beast__websocket__stream.async_write.parameters"></a></span><a class="link" href="async_write.html#beast.ref.boost__beast__websocket__stream.async_write.parameters">Parameters</a> 77 </h6> 78<div class="informaltable"><table class="table"> 79<colgroup> 80<col> 81<col> 82</colgroup> 83<thead><tr> 84<th> 85 <p> 86 Name 87 </p> 88 </th> 89<th> 90 <p> 91 Description 92 </p> 93 </th> 94</tr></thead> 95<tbody> 96<tr> 97<td> 98 <p> 99 <code class="computeroutput"><span class="identifier">buffers</span></code> 100 </p> 101 </td> 102<td> 103 <p> 104 A buffer sequence containing the entire message payload. The 105 implementation will make copies of this object as needed, but 106 ownership of the underlying memory is not transferred. The caller 107 is responsible for ensuring that the memory locations pointed 108 to by buffers remains valid until the completion handler is called. 109 </p> 110 </td> 111</tr> 112<tr> 113<td> 114 <p> 115 <code class="computeroutput"><span class="identifier">handler</span></code> 116 </p> 117 </td> 118<td> 119 <p> 120 The completion handler to invoke when the operation completes. 121 The implementation takes ownership of the handler by performing 122 a decay-copy. The equivalent function signature of the handler 123 must be: 124 </p> 125<pre xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="table-programlisting"><span class="keyword">void</span> <span class="identifier">handler</span><span class="special">(</span> 126 <span class="identifier">error_code</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">ec</span><span class="special">,</span> <span class="comment">// Result of operation</span> 127 <span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">bytes_transferred</span> <span class="comment">// Number of bytes sent from the</span> 128 <span class="comment">// buffers. If an error occurred,</span> 129 <span class="comment">// this will be less than the buffer_size.</span> 130<span class="special">);</span> 131</pre> 132 <p> 133 Regardless of whether the asynchronous operation completes immediately 134 or not, the handler will not be invoked from within this function. 135 Invocation of the handler will be performed in a manner equivalent 136 to using <code class="computeroutput"><span class="identifier">net</span><span class="special">::</span><span class="identifier">post</span></code>. 137 </p> 138 </td> 139</tr> 140</tbody> 141</table></div> 142</div> 143<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 144<td align="left"></td> 145<td align="right"><div class="copyright-footer">Copyright © 2016-2019 Vinnie 146 Falco<p> 147 Distributed under the Boost Software License, Version 1.0. (See accompanying 148 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>) 149 </p> 150</div></td> 151</tr></table> 152<hr> 153<div class="spirit-nav"> 154<a accesskey="p" href="write/overload2.html"><img src="../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../boost__beast__websocket__stream.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="write_some.html"><img src="../../../../../../../doc/src/images/next.png" alt="Next"></a> 155</div> 156</body> 157</html> 158
