My own RUBOUT

[kddlab!atr-la.atr.co.jp!myers@uunet.UU.NET (John K. Myers)]

I'm implementing a simple real-time interactor on top of (1) a Listener,
and (2) my own graphics window (a la MacWrite) on the Symbolics.  I need 
a Rubout.  The obvious method is to print a #\backspace and then do
(send window :clear-char).  Clear-char does not seem to do anything--
why not?  Other solutions, such as :clear-rest-of-line, mess with the
graphics in the graphics window.  Why doesn't clear-char work?  
Is there an easy way to get backspace to linewrap on a Listener,
without having to record pixel locations of the previous line and
do cursor controls?  [I'm using (read-char-no-hang) for input, and
format for output.]
   Thanks,
     John Myers~~