ass allows Signals2 to remain
      a header-only library.  You may still choose to use <code class="computeroutput">boost::mutex</code>
      if you wish, by specifying it as the <code class="computeroutput">Mutex</code> template type for your signals.
    </p>
<p>
      The <code class="computeroutput"><a class="link" href="../boost/signals2/dummy_mutex.html" title="Class dummy_mutex">boost::signals2::dummy_mutex</a></code> class is provided to allow
      performance sensitive single-threaded application