g unbuffered
output ports (say by using the open-file or fdopen procedure with the
&rsquo;0&rsquo; mode option or the R6RS open-file-output-port procedure with a
buffer-mode of none, or by calling setvbuf).
</p>
<p>Because this procedure takes a &rsquo;resume&rsquo; argument derived from the
a-sync procedure, it must (like the a-sync procedure) in practice be
called in the same thread as that in which the default glib main loop
runs.
</p>
<p>This procedure should not throw an exception unless memory is
exha