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<div class="titlepage"><div><div><h3 class="title">
<a name="boost_asio.reference.IoObjectService"></a><a class="link" href="IoObjectService.html" title="I/O object service requirements">I/O object service
requirements</a>
</h3></div></div></div>
<p>
An I/O object service must meet the requirements for a <a class="link" href="Service.html" title="Service requirements">service</a>,
as well as the requirements listed below.
</p>
<p>
In the table below, <code class="computeroutput"><span class="identifier">X</span></code> denotes
an I/O object service class, <code class="computeroutput"><span class="identifier">a</span></code>
and <code class="computeroutput"><span class="identifier">ao</span></code> denote values of type
<code class="computeroutput"><span class="identifier">X</span></code>, <code class="computeroutput"><span class="identifier">b</span></code>
and <code class="computeroutput"><span class="identifier">c</span></code> denote values of type
<code class="computeroutput"><span class="identifier">X</span><span class="special">::</span><span class="identifier">implementation_type</span></code>, and <code class="computeroutput"><span class="identifier">u</span></code> denotes an identifier.
</p>
<div class="table">
<a name="boost_asio.reference.IoObjectService.t0"></a><p class="title"><b>Table 17. IoObjectService requirements</b></p>
<div class="table-contents"><table class="table" summary="IoObjectService requirements">
<colgroup>
<col>
<col>
<col>
</colgroup>
<thead><tr>
<th>
<p>
expression
</p>
</th>
<th>
<p>
return type
</p>
</th>
<th>
<p>
assertion/note<br> pre/post-condition
</p>
</th>
</tr></thead>
<tbody>
<tr>
<td>
<p>
<code class="computeroutput"><span class="identifier">X</span><span class="special">::</span><span class="identifier">implementation_type</span></code>
</p>
</td>
<td>
</td>
<td>
</td>
</tr>
<tr>
<td>
<p>
<code class="computeroutput"><span class="identifier">X</span><span class="special">::</span><span class="identifier">implementation_type</span> <span class="identifier">u</span><span class="special">;</span></code>
</p>
</td>
<td>
</td>
<td>
<p>
note: <code class="computeroutput"><span class="identifier">X</span><span class="special">::</span><span class="identifier">implementation_type</span></code> has a public
default constructor and destructor.
</p>
</td>
</tr>
<tr>
<td>
<p>
</p>
<pre class="programlisting"><span class="identifier">a</span><span class="special">.</span><span class="identifier">construct</span><span class="special">(</span><span class="identifier">b</span><span class="special">);</span>
</pre>
<p>
</p>
</td>
<td>
</td>
<td>
</td>
</tr>
<tr>
<td>
<p>
</p>
<pre class="programlisting"><span class="identifier">a</span><span class="special">.</span><span class="identifier">destroy</span><span class="special">(</span><span class="identifier">b</span><span class="special">);</span>
</pre>
<p>
</p>
</td>
<td>
</td>
<td>
<p>
note: <code class="computeroutput"><span class="identifier">destroy</span><span class="special">()</span></code>
will only be called on a value that has previously been initialised
with <code class="computeroutput"><span class="identifier">construct</span><span class="special">()</span></code> or <code class="computeroutput"><span class="identifier">move_construct</span><span class="special">()</span></code>.
</p>
</td>
</tr>
<tr>
<td>
<p>
</p>
<pre class="programlisting"><span class="identifier">a</span><span class="special">.</span><span class="identifier">move_construct</span><span class="special">(</span><span class="identifier">b</span><span class="special">,</span> <span class="identifier">c</span><span class="special">);</span>
</pre>
<p>
</p>
</td>
<td>
</td>
<td>
<p>
note: only required for I/O objects that support movability.
</p>
</td>
</tr>
<tr>
<td>
<p>
</p>
<pre class="programlisting"><span class="identifier">a</span><span class="special">.</span><span class="identifier">move_assign</span><span class="special">(</span><span class="identifier">b</span><span class="special">,</span> <span class="identifier">ao</span><span class="special">,</span> <span class="identifier">c</span><span class="special">);</span>
</pre>
<p>
</p>
</td>
<td>
</td>
<td>
<p>
note: only required for I/O objects that support movability.
</p>
</td>
</tr>
</tbody>
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<td align="right"><div class="copyright-footer">Copyright © 2003-2015 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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