exit-to-system

["Curtis A. Scott" <cscott@bfly-vax.bbn.com>]

Now I know you don't think multiple threads of control are a good
thing, but QUIT has a fairly natural interpretation in the Multilisp-style
world.  It might mean "This computation has done the side-effects it
needed to do, so abandon it".  This implies a return to
the operating system (if there is one) if there are no other threads 
of control (since the work done by the REP loop has been declared
finished), or to reclamation of the task resources if the system as a whole
still has a goal.  This is also a natural interpretation on a multitasking
lisp machine.  Thus the concept is clear and not particularly 
machine-dependent.

--Curtis