> Exactly the problem.  We have an application that must run continuously
> for *months* while still displaying output to the buffer (thus we 
> can't completely turn off output), yet not eventually die because 
> a buffer fills up.

> - Dan

Try this (assuming you use the Franz ACL/Emacs interface):

(defvar max-acl-buffer-size 1000000
  "Maximal number of output bytes saved in the ACL buffer.")

(defadvice fi::subprocess-filter (before restrict-acl-buffer-size act pre com)
  "Restrict the buffer size of the ACL buffer to about `max-acl-buffer-size'."
  (let ((buffer (process-buffer (ad-get-arg 0))))
    (cond ((and buffer (eq buffer (get-buffer fi:common-lisp-buffer-name)))
           (save-excursion
             (set-buffer buffer)
             (if (> (point-max) max-acl-buffer-size)
                 (delete-region 
                  1 (- (point-max) 
                       (truncate (* 0.9 max-acl-buffer-size))))))))))

Enjoy,

Hans

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Hans Chalupsky                              USC Information Sciences Institute
<isi.edu at hans>                              4676 Admiralty Way
(310) 822-1511 Ext.745                      Marina del Rey, CA 90292
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