as await-geteveryline!, except that it provides a second
argument to &rsquo;proc&rsquo;, namely an escape continuation which can be invoked
by &rsquo;proc&rsquo; to cause the procedure to return before end-of-file is
reached.  Behavior is identical to await-geteveryline! if the
continuation is not invoked.
</p>
<p>This procedure will start a read watch on &rsquo;port&rsquo; for lines of input.
It calls &rsquo;await&rsquo; while waiting for input and will apply &rsquo;proc&rsquo; to any
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