ILGINS (II)                  3/15/72                  ILGINS (II)

NAME            ilgins  --  catch illegal instruction trap

SYNOPSIS        sys ilgins; arg  / ilgins = 33.

DESCRIPTION     ilgins allows a program to catch illegal instruc-

                tion traps.  If arg is zero, the normal instruc-

                tion trap handling is done: the process is termi-

                nated and a core image is produced.  If arg is a

                location within the program, control is passed to

                arg when the trap occurs.

                This call is used to implement the floating point

                simulator, which catches and interprets 11/45

                floating point instructions.

                To return after catching the ilgins trap, execute

                the rti instruction.

SEE ALSO        PDP-11 manual


BUGS            --