1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>write (4 of 16 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="../../../boost_asio.html" title="Boost.Asio"> 8<link rel="up" href="../write.html" title="write"> 9<link rel="prev" href="overload3.html" title="write (3 of 16 overloads)"> 10<link rel="next" href="overload5.html" title="write (5 of 16 overloads)"> 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="overload3.html"><img src="../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../write.html"><img src="../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../../boost_asio.html"><img src="../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="overload5.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="boost_asio.reference.write.overload4"></a><a class="link" href="overload4.html" title="write (4 of 16 overloads)">write (4 of 16 28 overloads)</a> 29</h4></div></div></div> 30<p> 31 Write a certain amount of data to a stream before returning. 32 </p> 33<pre class="programlisting">template< 34 typename <a class="link" href="../SyncWriteStream.html" title="Buffer-oriented synchronous write stream requirements">SyncWriteStream</a>, 35 typename <a class="link" href="../ConstBufferSequence.html" title="Constant buffer sequence requirements">ConstBufferSequence</a>, 36 typename <a class="link" href="../CompletionCondition.html" title="Completion condition requirements">CompletionCondition</a>> 37std::size_t write( 38 SyncWriteStream & s, 39 const ConstBufferSequence & buffers, 40 CompletionCondition completion_condition, 41 boost::system::error_code & ec, 42 typename enable_if< is_const_buffer_sequence< ConstBufferSequence >::value >::type * = 0); 43</pre> 44<p> 45 This function is used to write a certain number of bytes of data to a stream. 46 The call will block until one of the following conditions is true: 47 </p> 48<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> 49<li class="listitem"> 50 All of the data in the supplied buffers has been written. That is, 51 the bytes transferred is equal to the sum of the buffer sizes. 52 </li> 53<li class="listitem"> 54 The completion_condition function object returns 0. 55 </li> 56</ul></div> 57<p> 58 This operation is implemented in terms of zero or more calls to the stream's 59 write_some function. 60 </p> 61<h6> 62<a name="boost_asio.reference.write.overload4.h0"></a> 63 <span class="phrase"><a name="boost_asio.reference.write.overload4.parameters"></a></span><a class="link" href="overload4.html#boost_asio.reference.write.overload4.parameters">Parameters</a> 64 </h6> 65<div class="variablelist"> 66<p class="title"><b></b></p> 67<dl class="variablelist"> 68<dt><span class="term">s</span></dt> 69<dd><p> 70 The stream to which the data is to be written. The type must support 71 the SyncWriteStream concept. 72 </p></dd> 73<dt><span class="term">buffers</span></dt> 74<dd><p> 75 One or more buffers containing the data to be written. The sum of 76 the buffer sizes indicates the maximum number of bytes to write to 77 the stream. 78 </p></dd> 79<dt><span class="term">completion_condition</span></dt> 80<dd> 81<p> 82 The function object to be called to determine whether the write operation 83 is complete. The signature of the function object must be: 84</p> 85<pre class="programlisting">std::size_t completion_condition( 86 // Result of latest write_some operation. 87 const boost::system::error_code& error, 88 89 // Number of bytes transferred so far. 90 std::size_t bytes_transferred 91); 92</pre> 93<p> 94 A return value of 0 indicates that the write operation is complete. 95 A non-zero return value indicates the maximum number of bytes to 96 be written on the next call to the stream's write_some function. 97 </p> 98</dd> 99<dt><span class="term">ec</span></dt> 100<dd><p> 101 Set to indicate what error occurred, if any. 102 </p></dd> 103</dl> 104</div> 105<h6> 106<a name="boost_asio.reference.write.overload4.h1"></a> 107 <span class="phrase"><a name="boost_asio.reference.write.overload4.return_value"></a></span><a class="link" href="overload4.html#boost_asio.reference.write.overload4.return_value">Return 108 Value</a> 109 </h6> 110<p> 111 The number of bytes written. If an error occurs, returns the total number 112 of bytes successfully transferred prior to the error. 113 </p> 114</div> 115<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 116<td align="left"></td> 117<td align="right"><div class="copyright-footer">Copyright © 2003-2020 Christopher M. 118 Kohlhoff<p> 119 Distributed under the Boost Software License, Version 1.0. (See accompanying 120 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>) 121 </p> 122</div></td> 123</tr></table> 124<hr> 125<div class="spirit-nav"> 126<a accesskey="p" href="overload3.html"><img src="../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../write.html"><img src="../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../../boost_asio.html"><img src="../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="overload5.html"><img src="../../../../../doc/src/images/next.png" alt="Next"></a> 127</div> 128</body> 129</html> 130
