boost/doc/html/boost_asio/reference/SignalHandler.html
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<div class="titlepage"><div><div><h3 class="title">
<a name="boost_asio.reference.SignalHandler"></a><a class="link" href="SignalHandler.html" title="Signal handler requirements">Signal handler requirements</a>
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<p>
A signal handler must meet the requirements for a <a class="link" href="Handler.html" title="Handlers">handler</a>.
A value <code class="computeroutput">h</code> of a signal handler class should work correctly in
the expression <code class="computeroutput">h(ec, n)</code>, where <code class="computeroutput">ec</code> is an lvalue
of type <code class="computeroutput">const error_code</code> and <code class="computeroutput">n</code> is an lvalue of
type <code class="computeroutput">const int</code>.
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<h5>
<a name="boost_asio.reference.SignalHandler.h0"></a>
<span class="phrase"><a name="boost_asio.reference.SignalHandler.examples"></a></span><a class="link" href="SignalHandler.html#boost_asio.reference.SignalHandler.examples">Examples</a>
</h5>
<p>
A free function as a signal handler:
</p>
<pre class="programlisting">void signal_handler(
const boost::system::error_code&amp; ec,
int signal_number)
{
...
}
</pre>
<p>
A signal handler function object:
</p>
<pre class="programlisting">struct signal_handler
{
...
void operator()(
const boost::system::error_code&amp; ec,
int signal_number)
{
...
}
...
};
</pre>
<p>
A lambda as a signal handler:
</p>
<pre class="programlisting">my_signal_set.async_wait(
[](const boost::system::error_code&amp; ec,
int signal_number)
{
...
});
</pre>
<p>
A non-static class member function adapted to a signal handler using <code class="computeroutput">std::bind()</code>:
</p>
<pre class="programlisting">void my_class::signal_handler(
const boost::system::error_code&amp; ec,
int signal_number)
{
...
}
...
my_signal_set.async_wait(
std::bind(&amp;my_class::signal_handler,
this, std::placeholders::_1,
std::placeholders::_2));
</pre>
<p>
A non-static class member function adapted to a signal handler using <code class="computeroutput">boost::bind()</code>:
</p>
<pre class="programlisting">void my_class::signal_handler(
const boost::system::error_code&amp; ec,
int signal_number)
{
...
}
...
my_signal_set.async_wait(
boost::bind(&amp;my_class::signal_handler,
this, boost::asio::placeholders::error,
boost::asio::placeholders::signal_number));
</pre>
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<td align="right"><div class="copyright-footer">Copyright © 2003-2021 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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