doc/html/boost_asio/reference/const_buffer.html

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  26 <div class="titlepage"><div><div><h3 class="title">
  27 <a name="boost_asio.reference.const_buffer"></a><a class="link" href="const_buffer.html" title="const_buffer">const_buffer</a>
  28 </h3></div></div></div>
  29 <p>
  30         Holds a buffer that cannot be modified.
  31       </p>
  32 <pre class="programlisting"><span class="keyword">class</span> <span class="identifier">const_buffer</span>
  33 </pre>
  34 <h5>
  35 <a name="boost_asio.reference.const_buffer.h0"></a>
  36         <span class="phrase"><a name="boost_asio.reference.const_buffer.member_functions"></a></span><a class="link" href="const_buffer.html#boost_asio.reference.const_buffer.member_functions">Member
  37         Functions</a>
  38       </h5>
  39 <div class="informaltable"><table class="table">
  40 <colgroup>
  41 <col>
  42 <col>
  43 </colgroup>
  44 <thead><tr>
  45 <th>
  46                 <p>
  47                   Name
  48                 </p>
  49               </th>
  50 <th>
  51                 <p>
  52                   Description
  53                 </p>
  54               </th>
  55 </tr></thead>
  56 <tbody><tr>
  57 <td>
  58                 <p>
  59                   <a class="link" href="const_buffer/const_buffer.html" title="const_buffer::const_buffer"><span class="bold"><strong>const_buffer</strong></span></a>
  60                 </p>
  61               </td>
  62 <td>
  63                 <p>
  64                   Construct an empty buffer.
  65                 </p>
  66                 <p>
  67                   Construct a buffer to represent a given memory range.
  68                 </p>
  69                 <p>
  70                   Construct a non-modifiable buffer from a modifiable one.
  71                 </p>
  72               </td>
  73 </tr></tbody>
  74 </table></div>
  75 <h5>
  76 <a name="boost_asio.reference.const_buffer.h1"></a>
  77         <span class="phrase"><a name="boost_asio.reference.const_buffer.related_functions"></a></span><a class="link" href="const_buffer.html#boost_asio.reference.const_buffer.related_functions">Related
  78         Functions</a>
  79       </h5>
  80 <div class="informaltable"><table class="table">
  81 <colgroup>
  82 <col>
  83 <col>
  84 </colgroup>
  85 <thead><tr>
  86 <th>
  87                 <p>
  88                   Name
  89                 </p>
  90               </th>
  91 <th>
  92                 <p>
  93                   Description
  94                 </p>
  95               </th>
  96 </tr></thead>
  97 <tbody><tr>
  98 <td>
  99                 <p>
 100                   <a class="link" href="const_buffer/operator_plus_.html" title="const_buffer::operator+"><span class="bold"><strong>operator+</strong></span></a>
 101                 </p>
 102               </td>
 103 <td>
 104                 <p>
 105                   Create a new non-modifiable buffer that is offset from the start
 106                   of another.
 107                 </p>
 108               </td>
 109 </tr></tbody>
 110 </table></div>
 111 <p>
 112         The <a class="link" href="const_buffer.html" title="const_buffer"><code class="computeroutput"><span class="identifier">const_buffer</span></code></a>
 113         class provides a safe representation of a buffer that cannot be modified.
 114         It does not own the underlying data, and so is cheap to copy or assign.
 115       </p>
 116 <h5>
 117 <a name="boost_asio.reference.const_buffer.h2"></a>
 118         <span class="phrase"><a name="boost_asio.reference.const_buffer.accessing_buffer_contents"></a></span><a class="link" href="const_buffer.html#boost_asio.reference.const_buffer.accessing_buffer_contents">Accessing
 119         Buffer Contents</a>
 120       </h5>
 121 <p>
 122         The contents of a buffer may be accessed using the <a class="link" href="buffer_size.html" title="buffer_size"><code class="computeroutput"><span class="identifier">buffer_size</span></code></a> and <a class="link" href="buffer_cast.html" title="buffer_cast"><code class="computeroutput"><span class="identifier">buffer_cast</span></code></a> functions:
 123       </p>
 124 <pre class="programlisting"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">asio</span><span class="special">::</span><span class="identifier">const_buffer</span> <span class="identifier">b1</span> <span class="special">=</span> <span class="special">...;</span>
 125 <span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">s1</span> <span class="special">=</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">asio</span><span class="special">::</span><span class="identifier">buffer_size</span><span class="special">(</span><span class="identifier">b1</span><span class="special">);</span>
 126 <span class="keyword">const</span> <span class="keyword">unsigned</span> <span class="keyword">char</span><span class="special">*</span> <span class="identifier">p1</span> <span class="special">=</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">asio</span><span class="special">::</span><span class="identifier">buffer_cast</span><span class="special">&lt;</span><span class="keyword">const</span> <span class="keyword">unsigned</span> <span class="keyword">char</span><span class="special">*&gt;(</span><span class="identifier">b1</span><span class="special">);</span>
 127 </pre>
 128 <p>
 129         The <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">asio</span><span class="special">::</span><span class="identifier">buffer_cast</span></code> function permits violations
 130         of type safety, so uses of it in application code should be carefully considered.
 131       </p>
 132 <h5>
 133 <a name="boost_asio.reference.const_buffer.h3"></a>
 134         <span class="phrase"><a name="boost_asio.reference.const_buffer.requirements"></a></span><a class="link" href="const_buffer.html#boost_asio.reference.const_buffer.requirements">Requirements</a>
 135       </h5>
 136 <p>
 137         <span class="emphasis"><em>Header: </em></span><code class="literal">boost/asio/buffer.hpp</code>
 138       </p>
 139 <p>
 140         <span class="emphasis"><em>Convenience header: </em></span><code class="literal">boost/asio.hpp</code>
 141       </p>
 142 </div>
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 145 <td align="right"><div class="copyright-footer">Copyright &#169; 2003-2014 Christopher M. Kohlhoff<p>
 146         Distributed under the Boost Software License, Version 1.0. (See accompanying
 147         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>)
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