 received (without the terminating &rsquo;\n&rsquo;
character).  &rsquo;proc&rsquo; should be a procedure taking two arguments, a
string as the first argument containing the line of text read, and an
escape continuation as its second.
</p>
<p>The event loop will not be blocked by this procedure even if only
individual characters or part characters are available at any one time
(although if &rsquo;port&rsquo; references a socket, it should be non-blocking for
this to be guaranteed).  It is intended to be cal