user to bring it to an end at the right time by calling
g-source-remove in the waitable procedure on the id tag returned by
this procedure.  Any port for the file descriptor &rsquo;fd&rsquo; is not
referenced for garbage collection purposes - it must remain valid
while the read watch is active.  This procedure is mainly intended as
something from which higher-level asynchronous file operations can be
constructed, such as the await-glib-getline procedure.
</p>
<p>File watches in guile-gnome are implemented u