TM resources: user names

The user name and the user ID are usually the same; however, user exits and descriptors can override the user name. The user is the user signed on to a dynamic terminal or parallel session subpool and has associated work and status. The user ID identifies a person signed on to a terminal for security authorization by a security product such as RACF®.

User name uniqueness

IMS enforces name uniqueness for user names to ensure data integrity for users. Users are defined to RM during user signon or ISC session initiation. If the user is already active, IMS rejects the signon or session initiation.

For ISC sessions, user name uniqueness can be ignored by using the DFSINTX0 user exit routine. See IMS Version 15.6 Exit Routines for more information about this exit routine.

User creation and deletion

When a user becomes active during user signon, IMS defines it to the RM. If the user is active on another system, signon is rejected. IMS also defines users to RM when recoverable commands affecting significant status are processed.

IMS deletes the user from RM when the user becomes inactive and no significant data exists. A user is deleted in three situations:

During user signoff
When a command deleting significant status is processed
During resource cleanup after an IMS failure and no significant status exits