11/3/71                                            SYS BREAK (II)





NAME            break  --  set program break



SYNOPSIS        sys     break; addr     / break = 17.



DESCRIPTION     break sets the system's idea of the highest loca-

                tion used by the program to addr.  Locations

                greater than addr and below the stack pointer are

                not swapped and are thus liable to unexpected

                modification.



                If the argument is 0 or higher than the stack

                pointer the entire 4K word user core area is

                swapped.



                When a program begins execution via exec the

                break is set at the highest location defined by

                the program and data storage areas.  Ordinarily,

                therefore, only programs with growing data areas

                need to use break.



FILES           --



SEE ALSO        exec



DIAGNOSTICS     none; strange addresses cause the break to be set

                to include all of core.



BUGS            --



OWNER           ken, dmr