MAREN exits for reserving tapes

There are two different exits for the MAREN function “tape reservation”:

• the request exit allows the reservation request to be checked and rejected if necessary

• the return exit only allows evaluations, since the reservation has already taken place.

The following function names are possible when calling the exits for new reservations:

LAFUNKNM	Action involved
MARENFA2	Implicit reservation by specification of the archive number of a free tape in the ARCHIVE statements SAVE, EXPORT and POOL ADD=<tvsn>
MARENUCP	Reservation via the automatic free tape allocation facility of MARENs
RESERVE	MAREN statement RESERVE-FREE-VOLUME
RESERVE1	MARENADM statement RESERVE-FREE-VOLUME

Passing parameters

The following information is passed to the individual computer center exits:

Register 1	A(parameter area) The parameter area comprises a word containing the address of the catalog entry. The individual catalog entry fields can be addressed symbolically via the dummy section MARENA.
Register 13	A(save area) The save area provided by MAREN is 18 words long.
Register 14	A(return) For returning directly to MAREN.
Register 15	A(exit routine) Start address of the called exit routine.

All other registers are set to “binary zero”.