3rdparty/boost_1_81_0/doc/html/signals2/faq.html

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<a name="signals2.faq"></a>Frequently Asked Questions</h2></div></div></div>
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<dt>1. <a href="faq.html#id-1.3.35.8.2.1">Don't noncopyable signal semantics mean that a class
        with a signal member will be noncopyable as well?</a>
</dt>
<dt>2. <a href="faq.html#id-1.3.35.8.2.2">Is Boost.Signals2 thread-safe?</a>
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<a name="id-1.3.35.8.2.1"></a><a name="id-1.3.35.8.2.1.1"></a><p><b>1.</b></p>
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<td align="left" valign="top"><p>Don't noncopyable signal semantics mean that a class
        with a signal member will be noncopyable as well?</p></td>
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<td align="left" valign="top"><p>No. The compiler will not be able to generate a copy
        constructor or copy assignment operator for your class if it
        has a signal as a member, but you are free to write your own
        copy constructor and/or copy assignment operator. Just don't
        try to copy the signal.</p></td>
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<a name="id-1.3.35.8.2.2"></a><a name="id-1.3.35.8.2.2.1"></a><p><b>2.</b></p>
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<td align="left" valign="top"><p>Is Boost.Signals2 thread-safe?</p></td>
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<p>
          Yes, as long as the Mutex template parameter is not set to
          a fake mutex type like <code class="computeroutput"><a class="link" href="../boost/signals2/dummy_mutex.html" title="Class dummy_mutex">boost::signals2::dummy_mutex</a></code>.
          Also, if your slots depend on objects which may be destroyed concurrently
          with signal invocation, you will need to use automatic connection management.
          That is, the objects will need to be owned by
          <code class="computeroutput"><a class="link" href="../boost/shared_ptr.html" title="Class template shared_ptr">shared_ptr</a></code> and passed to the slot's
          <code class="computeroutput"><a class="link" href="../boost/signals2/slot.html#id-1_3_35_6_12_5_1_1_17_1-bb">track</a></code>() method before the slot is connected.
          The <code class="computeroutput"><a class="link" href="../boost/signals2/trackable.html" title="Class trackable">signals2::trackable</a></code> scheme of automatic connection management
          is NOT thread-safe, and is only provided to ease porting of single-threaded
          code from Boost.Signals to Boost.Signals2.
        </p>
<p>See the documentation section on <a class="link" href="thread-safety.html" title="Thread-Safety">thread-safety</a>
          for more information.
        </p>
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<td align="left"><p><small>Last revised: June 12, 2007 at 14:01:23 -0400</small></p></td>
<td align="right"><div class="copyright-footer">Copyright © 2001-2004 Douglas Gregor<br>Copyright © 2007-2009 Frank Mori Hess<p>Distributed under the Boost
    Software License, Version 1.0. (See accompanying file
    <code class="filename">LICENSE_1_0.txt</code> or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)</p>
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