Freeing a memory object

When your program no longer needs the memory object, it uses IARV64 DETACH to free (delete) the memory object. You can free memory objects that are related to each other through the user token defined on the IARV64 GETSTOR service. Additionally, all programs can use the following parameters:

MATCH=SINGLE,MEMOBJSTART frees a specific memory object, as identified by its origin address.
MATCH=USERTOKEN, USERTKN frees a related set of memory objects by providing the user token specified when the memory objects were created.
COND=YES makes the request conditional, but only when you also pass a user token. IBM® recommends you use COND to avoid having the program abend because it asked to free a memory object that doesn't exist.

Three conditions to avoid when you try to free a memory object are:

Freeing a memory object that does not exist.
If you try to free a memory object that doesn't exist, the system abends your program.
Freeing a memory object that has I/O in progress.

If you specify the COND=YES parameter, you must also specify a user token. In the recovery routine that gets control at an abend, you can ignore the abend and leave the memory object in an unusable state.

As part of normal task termination, RTM frees the memory objects owned by the terminating task.