1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>mutable_buffer</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="../reference.html" title="Reference"> 9<link rel="prev" href="multiple_exceptions/what.html" title="multiple_exceptions::what"> 10<link rel="next" href="mutable_buffer/data.html" title="mutable_buffer::data"> 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="multiple_exceptions/what.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../reference.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="mutable_buffer/data.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a> 24</div> 25<div class="section"> 26<div class="titlepage"><div><div><h3 class="title"> 27<a name="boost_asio.reference.mutable_buffer"></a><a class="link" href="mutable_buffer.html" title="mutable_buffer">mutable_buffer</a> 28</h3></div></div></div> 29<p> 30 Holds a buffer that can be modified. 31 </p> 32<pre class="programlisting">class mutable_buffer 33</pre> 34<h5> 35<a name="boost_asio.reference.mutable_buffer.h0"></a> 36 <span class="phrase"><a name="boost_asio.reference.mutable_buffer.member_functions"></a></span><a class="link" href="mutable_buffer.html#boost_asio.reference.mutable_buffer.member_functions">Member Functions</a> 37 </h5> 38<div class="informaltable"><table class="table"> 39<colgroup> 40<col> 41<col> 42</colgroup> 43<thead><tr> 44<th> 45 <p> 46 Name 47 </p> 48 </th> 49<th> 50 <p> 51 Description 52 </p> 53 </th> 54</tr></thead> 55<tbody> 56<tr> 57<td> 58 <p> 59 <a class="link" href="mutable_buffer/data.html" title="mutable_buffer::data"><span class="bold"><strong>data</strong></span></a> 60 </p> 61 </td> 62<td> 63 <p> 64 Get a pointer to the beginning of the memory range. 65 </p> 66 </td> 67</tr> 68<tr> 69<td> 70 <p> 71 <a class="link" href="mutable_buffer/mutable_buffer.html" title="mutable_buffer::mutable_buffer"><span class="bold"><strong>mutable_buffer</strong></span></a> <span class="silver">[constructor]</span> 72 </p> 73 </td> 74<td> 75 <p> 76 Construct an empty buffer. <br> <span class="silver"> —</span><br> Construct a buffer to 77 represent a given memory range. 78 </p> 79 </td> 80</tr> 81<tr> 82<td> 83 <p> 84 <a class="link" href="mutable_buffer/operator_plus__eq_.html" title="mutable_buffer::operator+="><span class="bold"><strong>operator+=</strong></span></a> 85 </p> 86 </td> 87<td> 88 <p> 89 Move the start of the buffer by the specified number of bytes. 90 </p> 91 </td> 92</tr> 93<tr> 94<td> 95 <p> 96 <a class="link" href="mutable_buffer/size.html" title="mutable_buffer::size"><span class="bold"><strong>size</strong></span></a> 97 </p> 98 </td> 99<td> 100 <p> 101 Get the size of the memory range. 102 </p> 103 </td> 104</tr> 105</tbody> 106</table></div> 107<h5> 108<a name="boost_asio.reference.mutable_buffer.h1"></a> 109 <span class="phrase"><a name="boost_asio.reference.mutable_buffer.related_functions"></a></span><a class="link" href="mutable_buffer.html#boost_asio.reference.mutable_buffer.related_functions">Related Functions</a> 110 </h5> 111<div class="informaltable"><table class="table"> 112<colgroup> 113<col> 114<col> 115</colgroup> 116<thead><tr> 117<th> 118 <p> 119 Name 120 </p> 121 </th> 122<th> 123 <p> 124 Description 125 </p> 126 </th> 127</tr></thead> 128<tbody><tr> 129<td> 130 <p> 131 <a class="link" href="mutable_buffer/operator_plus_.html" title="mutable_buffer::operator+"><span class="bold"><strong>operator+</strong></span></a> 132 </p> 133 </td> 134<td> 135 <p> 136 Create a new modifiable buffer that is offset from the start of 137 another. 138 </p> 139 </td> 140</tr></tbody> 141</table></div> 142<p> 143 The <a class="link" href="mutable_buffer.html" title="mutable_buffer"><code class="computeroutput">mutable_buffer</code></a> 144 class provides a safe representation of a buffer that can be modified. It 145 does not own the underlying data, and so is cheap to copy or assign. 146 </p> 147<h5> 148<a name="boost_asio.reference.mutable_buffer.h2"></a> 149 <span class="phrase"><a name="boost_asio.reference.mutable_buffer.accessing_buffer_contents"></a></span><a class="link" href="mutable_buffer.html#boost_asio.reference.mutable_buffer.accessing_buffer_contents">Accessing 150 Buffer Contents</a> 151 </h5> 152<p> 153 The contents of a buffer may be accessed using the <code class="computeroutput">data()</code> and 154 <code class="computeroutput">size()</code> member functions: 155 </p> 156<pre class="programlisting">boost::asio::mutable_buffer b1 = ...; 157std::size_t s1 = b1.size(); 158unsigned char* p1 = static_cast<unsigned char*>(b1.data()); 159</pre> 160<p> 161 The <code class="computeroutput">data()</code> member function permits violations of type safety, 162 so uses of it in application code should be carefully considered. 163 </p> 164<h5> 165<a name="boost_asio.reference.mutable_buffer.h3"></a> 166 <span class="phrase"><a name="boost_asio.reference.mutable_buffer.requirements"></a></span><a class="link" href="mutable_buffer.html#boost_asio.reference.mutable_buffer.requirements">Requirements</a> 167 </h5> 168<p> 169 <span class="emphasis"><em>Header: </em></span><code class="literal">boost/asio/buffer.hpp</code> 170 </p> 171<p> 172 <span class="emphasis"><em>Convenience header: </em></span><code class="literal">boost/asio.hpp</code> 173 </p> 174</div> 175<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 176<td align="left"></td> 177<td align="right"><div class="copyright-footer">Copyright © 2003-2020 Christopher M. 178 Kohlhoff<p> 179 Distributed under the Boost Software License, Version 1.0. (See accompanying 180 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>) 181 </p> 182</div></td> 183</tr></table> 184<hr> 185<div class="spirit-nav"> 186<a accesskey="p" href="multiple_exceptions/what.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../reference.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="mutable_buffer/data.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a> 187</div> 188</body> 189</html> 190
