The User Address Space Exit (TDPUAX) is available only in the z/OS environment.
It is called in the address space of the application when an application initiates a request to the database.
The exit can accept, reject, “validate,” or modify the logon string of the caller.
The exit can be activated using the TDP ENABLE UAX command, either as part of TDP startup in TDPPARM, or anytime thereafter. It can be deactivated anytime using the TDP DISABLE UAX command.
If the TDPUAX module is replaced, the new version can be used by first deactivating the old version using the TDP DISABLE UAX command then activating the new version using the TDP ENABLE UAX command. Between the two commands, TDPUAX is not being used.