QUIT

        [SIC\]QUIT [ALL]

    When typed after a pause, QUIT aborts the execution of  the  interrupted
    level. QUIT returns an error to the previous level to signal this anoma-
    lous end. The previous level is then also interrupted to  allow  a  com-
    plete  error  recovery. Note that this behaviour depends on the ON ERROR
    command. QUIT can also be used to abort FOR-NEXT loop compilation.

    If argument ALL is present, all nested procedures are aborted,  and  SIC
    goes back to base level.

    In interactive sessions, QUIT should be used instead of BREAK and RETURN
    because it allows extra decision at run time. QUIT used as the error re-
    covery command is equivalent to RETURN ERROR.