Insane_DNS/libraries/asio-1.28.1/doc/asio/reference/buffer_cast.html

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<div class="titlepage"><div><div><h3 class="title">
<a name="asio.reference.buffer_cast"></a><a class="link" href="buffer_cast.html" title="buffer_cast">buffer_cast</a>
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<p>
<a class="indexterm" name="asio.indexterm.buffer_cast"></a>
</p>
<p>
(Deprecated: Use the <code class="computeroutput"><span class="identifier">data</span><span class="special">()</span></code> member function.) The <code class="computeroutput"><span class="identifier">asio</span><span class="special">::</span><span class="identifier">buffer_cast</span></code>
function is used to obtain a pointer to the underlying memory region associated
with a buffer.
</p>
<p>
Cast a non-modifiable buffer to a specified pointer to POD type.
</p>
<pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span>
<span class="keyword">typename</span> <span class="identifier">PointerToPodType</span><span class="special">&gt;</span>
<span class="identifier">PointerToPodType</span> <a class="link" href="buffer_cast/overload1.html" title="buffer_cast (1 of 2 overloads)">buffer_cast</a><span class="special">(</span>
<span class="keyword">const</span> <span class="identifier">mutable_buffer</span> <span class="special">&amp;</span> <span class="identifier">b</span><span class="special">);</span>
<span class="emphasis"><em>» <a class="link" href="buffer_cast/overload1.html" title="buffer_cast (1 of 2 overloads)">more...</a></em></span>
<span class="keyword">template</span><span class="special">&lt;</span>
<span class="keyword">typename</span> <span class="identifier">PointerToPodType</span><span class="special">&gt;</span>
<span class="identifier">PointerToPodType</span> <a class="link" href="buffer_cast/overload2.html" title="buffer_cast (2 of 2 overloads)">buffer_cast</a><span class="special">(</span>
<span class="keyword">const</span> <span class="identifier">const_buffer</span> <span class="special">&amp;</span> <span class="identifier">b</span><span class="special">);</span>
<span class="emphasis"><em>» <a class="link" href="buffer_cast/overload2.html" title="buffer_cast (2 of 2 overloads)">more...</a></em></span>
</pre>
<h5>
<a name="asio.reference.buffer_cast.h0"></a>
<span><a name="asio.reference.buffer_cast.examples_"></a></span><a class="link" href="buffer_cast.html#asio.reference.buffer_cast.examples_">Examples:</a>
</h5>
<p>
To access the memory of a non-modifiable buffer, use:
</p>
<pre class="programlisting"><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>
<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">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>
</pre>
<p>
To access the memory of a modifiable buffer, use:
</p>
<pre class="programlisting"><span class="identifier">asio</span><span class="special">::</span><span class="identifier">mutable_buffer</span> <span class="identifier">b2</span> <span class="special">=</span> <span class="special">...;</span>
<span class="keyword">unsigned</span> <span class="keyword">char</span><span class="special">*</span> <span class="identifier">p2</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">unsigned</span> <span class="keyword">char</span><span class="special">*&gt;(</span><span class="identifier">b2</span><span class="special">);</span>
</pre>
<p>
The <code class="computeroutput"><span class="identifier">asio</span><span class="special">::</span><span class="identifier">buffer_cast</span></code> function permits violations
of type safety, so uses of it in application code should be carefully considered.
</p>
<h5>
<a name="asio.reference.buffer_cast.h1"></a>
<span><a name="asio.reference.buffer_cast.requirements"></a></span><a class="link" href="buffer_cast.html#asio.reference.buffer_cast.requirements">Requirements</a>
</h5>
<p>
<span class="emphasis"><em>Header: </em></span><code class="literal">asio/buffer.hpp</code>
</p>
<p>
<span class="emphasis"><em>Convenience header: </em></span><code class="literal">asio.hpp</code>
</p>
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<div class="copyright-footer">Copyright © 2003-2023 Christopher M. Kohlhoff<p>
Distributed under the Boost Software License, Version 1.0. (See accompanying
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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