(defun quit (&optional code)
;; This group from "clocc-port/ext.lisp"
#+allegro (excl:exit code)
#+clisp (#+lisp=cl ext:quit #-lisp=cl lisp:quit code)
#+cmu (ext:quit code)
#+cormanlisp (win32:exitprocess code)
#+gcl (lisp:bye code) ; XXX Or is it LISP::QUIT?
#+lispworks (lw:quit :status code)
#+lucid (lcl:quit code)
#+sbcl (sb-ext:exit :code code)
;; This group from Maxima
#+kcl (lisp::bye) ; XXX Does this take an arg?
#+scl (ext:quit code) ; XXX Pretty sure this *does*.
#+(or openmcl mcl) (ccl::quit)
#+abcl (cl-user::quit)
#+ecl (si:quit)
;; This group from <hebi...@math.uni.wroc.pl>
#+poplog (poplog::bye) ; XXX Does this take an arg?
#-(or allegro clisp cmu cormanlisp gcl lispworks lucid sbc
kcl scl openmcl mcl abcl ecl)
(error 'not-implemented :proc (list 'quit code)))
Taken from Rob Warnock's post "How to programmatically exit?"
compatibility layers