which
supplies the &rsquo;await&rsquo; and &rsquo;resume&rsquo; arguments).  The &rsquo;loop&rsquo; argument is
optional: this procedure operates on the event loop passed in as an
argument, or if none is passed (or #f is passed), on the default event
loop.
</p>
<p>Calling this procedure is equivalent to calling await-timeout! with a
&rsquo;proc&rsquo; argument comprising a lambda expression that does nothing.
</p>
<p>This procedure must (like the a-sync procedure) be called in the same
thread as that in whi