a datum from a sender running on the same event loop as
the receiver, via one or more meeting objects &rsquo;m0 m1 ...&rsquo;.  If no
sender is waiting to pass the datum, this procedure waits until a
sender calls meeting-send on one of the meeting objects to provide the
datum.  If a sender is already waiting, this procedure returns
immediately with the datum supplied.
</p>
<p>The &rsquo;loop&rsquo; argument is optional.  If not supplied, or #f is passed,
this procedure will use the default event loop.  It i