s, failure, or exception) is sent
back to the message queue of the object containing the call
(<a class="reference internal" href="../../glossary.html#term-this"><span class="xref std std-term">this</span></a>).</p>
<p>The <code class="docutils literal notranslate"><span class="pre">threaded_once/2</span></code> variant returns a threaded call identifier tag that
can be used with the <a class="reference internal" href="threaded_exit_1_2.html#predicates-threaded-exit-1-2"><span class="std std-ref">threaded_e