1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>http::async_write_some</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="../ref.html" title="This Page Intentionally Left Blank 2/2"> 9<link rel="prev" href="boost__beast__http__write_some/overload2.html" title="http::write_some (2 of 2 overloads)"> 10<link rel="next" href="boost__beast__http__write_header.html" title="http::write_header"> 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="boost__beast__http__write_some/overload2.html"><img src="../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../ref.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="boost__beast__http__write_header.html"><img src="../../../../../../doc/src/images/next.png" alt="Next"></a> 24</div> 25<div class="section"> 26<div class="titlepage"><div><div><h4 class="title"> 27<a name="beast.ref.boost__beast__http__async_write_some"></a><a class="link" href="boost__beast__http__async_write_some.html" title="http::async_write_some">http::async_write_some</a> 28</h4></div></div></div> 29<p> 30 <a class="indexterm" name="idm46057504902960"></a> 31 </p> 32<p> 33 Write part of a message to a stream asynchronously using a serializer. 34 </p> 35<h5> 36<a name="beast.ref.boost__beast__http__async_write_some.h0"></a> 37 <span class="phrase"><a name="beast.ref.boost__beast__http__async_write_some.synopsis"></a></span><a class="link" href="boost__beast__http__async_write_some.html#beast.ref.boost__beast__http__async_write_some.synopsis">Synopsis</a> 38 </h5> 39<p> 40 Defined in header <code class="literal"><<a href="../../../../../../boost/beast/http/write.hpp" target="_top">boost/beast/http/write.hpp</a>></code> 41 </p> 42<pre class="programlisting"><span class="keyword">template</span><span class="special"><</span> 43 <span class="keyword">class</span> <a href="../../../../../../doc/html/boost_asio/reference/AsyncWriteStream.html" target="_top"><span class="emphasis"><em>AsyncWriteStream</em></span></a><span class="special">,</span> 44 <span class="keyword">bool</span> <span class="identifier">isRequest</span><span class="special">,</span> 45 <span class="keyword">class</span> <a class="link" href="../concepts/Body.html" title="Body"><span class="emphasis"><em>Body</em></span></a><span class="special">,</span> 46 <span class="keyword">class</span> <a class="link" href="../concepts/Fields.html" title="Fields"><span class="emphasis"><em>Fields</em></span></a><span class="special">,</span> 47 <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> <span class="identifier">executor_type</span><span class="special"><</span><span class="identifier">AsyncWriteStream</span><span class="special">>>></span> 48<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> 49<span class="identifier">async_write_some</span><span class="special">(</span> 50 <span class="identifier">AsyncWriteStream</span><span class="special">&</span> <span class="identifier">stream</span><span class="special">,</span> 51 <span class="identifier">serializer</span><span class="special"><</span> <span class="identifier">isRequest</span><span class="special">,</span> <span class="identifier">Body</span><span class="special">,</span> <span class="identifier">Fields</span> <span class="special">>&</span> <span class="identifier">sr</span><span class="special">,</span> 52 <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="boost__beast__executor_type.html" title="executor_type">executor_type</a><span class="special"><</span> <span class="identifier">AsyncWriteStream</span> <span class="special">>>{});</span> 53</pre> 54<h5> 55<a name="beast.ref.boost__beast__http__async_write_some.h1"></a> 56 <span class="phrase"><a name="beast.ref.boost__beast__http__async_write_some.description"></a></span><a class="link" href="boost__beast__http__async_write_some.html#beast.ref.boost__beast__http__async_write_some.description">Description</a> 57 </h5> 58<p> 59 This function is used to write part of a message to a stream asynchronously 60 using a caller-provided HTTP/1 serializer. The function call always returns 61 immediately. The asynchronous operation will continue until one of the following 62 conditions is true: 63 </p> 64<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> 65<li class="listitem"> 66 One or more bytes have been transferred. 67 </li> 68<li class="listitem"> 69 The function <a class="link" href="boost__beast__http__serializer/is_done.html" title="http::serializer::is_done"><code class="computeroutput"><span class="identifier">serializer</span><span class="special">::</span><span class="identifier">is_done</span></code></a> returns <code class="computeroutput"><span class="keyword">true</span></code> 70 </li> 71<li class="listitem"> 72 An error occurs on the stream. 73 </li> 74</ul></div> 75<p> 76 This operation is implemented in terms of zero or more calls to the stream's 77 <code class="computeroutput"><span class="identifier">async_write_some</span></code> function, 78 and is known as a <span class="emphasis"><em>composed operation</em></span>. The program must 79 ensure that the stream performs no other writes until this operation completes. 80 The amount of data actually transferred is controlled by the behavior of 81 the underlying stream, subject to the buffer size limit of the serializer 82 obtained or set through a call to <a class="link" href="boost__beast__http__serializer/limit/overload1.html" title="http::serializer::limit (1 of 2 overloads)"><code class="computeroutput"><span class="identifier">serializer</span><span class="special">::</span><span class="identifier">limit</span></code></a>. Setting a limit and performing 83 bounded work helps applications set reasonable timeouts. It also allows application-level 84 flow control to function correctly. For example when using a TCP/IP based 85 stream. 86 </p> 87<h5> 88<a name="beast.ref.boost__beast__http__async_write_some.h2"></a> 89 <span class="phrase"><a name="beast.ref.boost__beast__http__async_write_some.parameters"></a></span><a class="link" href="boost__beast__http__async_write_some.html#beast.ref.boost__beast__http__async_write_some.parameters">Parameters</a> 90 </h5> 91<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">stream</span></code> 113 </p> 114 </td> 115<td> 116 <p> 117 The stream to which the data is to be written. The type must support 118 the <span class="emphasis"><em>AsyncWriteStream</em></span> concept. 119 </p> 120 </td> 121</tr> 122<tr> 123<td> 124 <p> 125 <code class="computeroutput"><span class="identifier">sr</span></code> 126 </p> 127 </td> 128<td> 129 <p> 130 The serializer to use. The object must remain valid at least until 131 the handler is called; ownership is not transferred. 132 </p> 133 </td> 134</tr> 135<tr> 136<td> 137 <p> 138 <code class="computeroutput"><span class="identifier">handler</span></code> 139 </p> 140 </td> 141<td> 142 <p> 143 The completion handler to invoke when the operation completes. 144 The implementation takes ownership of the handler by performing 145 a decay-copy. The equivalent function signature of the handler 146 must be: 147 </p> 148<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> 149 <span class="identifier">error_code</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">error</span><span class="special">,</span> <span class="comment">// result of operation</span> 150 <span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">bytes_transferred</span> <span class="comment">// the number of bytes written to the stream</span> 151<span class="special">);</span> 152</pre> 153 <p> 154 Regardless of whether the asynchronous operation completes immediately 155 or not, the handler will not be invoked from within this function. 156 Invocation of the handler will be performed in a manner equivalent 157 to using <a class="link" href="boost__beast__http__verb.html" title="http::verb"><code class="computeroutput"><span class="identifier">net</span><span class="special">::</span><span class="identifier">post</span></code></a>. 158 </p> 159 </td> 160</tr> 161</tbody> 162</table></div> 163<h5> 164<a name="beast.ref.boost__beast__http__async_write_some.h3"></a> 165 <span class="phrase"><a name="beast.ref.boost__beast__http__async_write_some.see_also"></a></span><a class="link" href="boost__beast__http__async_write_some.html#beast.ref.boost__beast__http__async_write_some.see_also">See Also</a> 166 </h5> 167<p> 168 <a class="link" href="boost__beast__http__serializer.html" title="http::serializer"><code class="computeroutput"><span class="identifier">serializer</span></code></a> 169 </p> 170</div> 171<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 172<td align="left"></td> 173<td align="right"><div class="copyright-footer">Copyright © 2016-2019 Vinnie 174 Falco<p> 175 Distributed under the Boost Software License, Version 1.0. (See accompanying 176 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>) 177 </p> 178</div></td> 179</tr></table> 180<hr> 181<div class="spirit-nav"> 182<a accesskey="p" href="boost__beast__http__write_some/overload2.html"><img src="../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../ref.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="boost__beast__http__write_header.html"><img src="../../../../../../doc/src/images/next.png" alt="Next"></a> 183</div> 184</body> 185</html> 186
