pause
PAUSE
command or operation. Enters an interactive pause. The user is
prompted for instructions, as at toplevel, but with a prompt that
includes the name of the procedure in which PAUSE was invoked.
Local variables of that procedure are available during the pause.
PAUSE outputs if the pause is ended by a CONTINUE with an input.
If the variable ERRACT exists, and an error condition occurs, the
contents of that variable are run as an instructionlist. Typically
ERRACT is given the value [PAUSE] so that an interactive pause will
be entered in the event of an error. This allows the user to check
values of local variables at the time of the error.
Typing the system quit character (alt-S for wxWidgets; otherwise
normally control-\ for Unix, control-W for DOS, or command-comma for
Mac) will also enter a pause.