[no subject]

[RG at MIT-AI (Richard Greenblatt)]

  System 19.4 has sequence breaks!  To turn them on, do (SI:SB-ON <mask>),
where <Mask> is a bitwise decoded number that controls which conditions can cause
a sequence break.
   The 1 bit enables the CALL key,
   The 2 bit enables all keyboard keys,
   The 4 bit causes a SB on the receipt of any CHAOSnet packet.

   A sequence break forces a call to the scheduler.  Due to its round robin
nature, the scheduler will examine all other processes before returnning to
the one which was running at the time of the sequence break.

   The CALL key will reset the current process if the selected window is a 
lisp-listener.  Otherwise, it will reset and select the TOP-WINDOW.
  <escape>B causes a break, ie, forces a call to the error handler.
You can do all the usual things, inspect the stack, etc, including
continuing via cntrl-C.
  It seems to work fairly well (ie hasnt dropped dead on me for quite a while).
I recommend (SI:SB-ON 2) unless you are actually having problems of CHAOSnet
connections dropping during long thinks, in which case, 6 might be worth a try.
  A warm boot turns off SBs, so you must turn them on again if desired.