GLMOD: Change global protect key macro

All records in the GL1 or GL3 areas reside in an area of real main storage with a protection key different from that in the program status word (PSW) for application programs. Before an application program can modify any field in these areas, the GLMOD macro must be issued. GLMOD changes the protection key in the PSW of the application program to match the key of the format-1 global area or sets on storage protection override. Storage protection override allows the application program to access storage that has a storage protection key of 9.

The following example shows how to change the protection key in an area of real storage:

|...+....1....+....2....+....3....+....4....+....5....+....6....+....7...
LABEL    GLOBZ REGR=R1
.
.
.
LABEL    GLMOD GLOBAL1     Change to the format-1 global area storage
                           protection key. ‘GLOBAL1’ is the
                           default and need not be coded.