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

This would be a kludge, but what about either an Emacs Lisp function or a ACL
function that periodically woke up and cleared out all but the last x lines of
the buffer?
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Roy M. Turner, Assistant Professor () E-mail: <umcs.maine.edu at rmt>               
Department of Computer Science     () WWW:    http://cdps.umcs.maine.edu/~rmt  
5752 Neville Hall                  () Phone:  (207)581-3909                    
University of Maine                () FAX:    (207)581-4977                    
Orono, ME 04469-5752               () I use Lisp because I know C, C++, Ada,...