Managing system-managed tape library volumes: EDGLCSUX

DFSMSrmm uses the OAM installation exits CBRUXCUA, CBRUXEJC, CBRUXENT, and CBRUXVNL as described in Table 1 to manage the tape volumes defined in system-managed tape libraries. DFSMSrmm supplies Assembler source code for these installation exits, which is installed on your system as modules CBRUXCUA, CBRUXEJC, CBRUXENT, and CBRUXVNL. The sample CBRUXEJC, CBRUXENT, and CBRUXVNL exits show how to call the DFSMSrmm API. The use of the API is optional and must be enabled by the customer. The customer must also write code to process the results of the call to the API. The sample code shows how to list the volume being processed by OAM using the DFSMSrmm API. You can modify the source code to include your own function or merge with another product's supplied code.

DFSMSrmm uses EDGLCSUX to support these functions:

Tracking TCDB changes by updating the DFSMSrmm control data set.
Updating the CBRUXxxx parameter list based on DFSMSrmm information.
Partitioning a library.
Handling volume-not-in-library conditions.
Controlling the purging of TCDB volume entries at eject time.

You can use the DFSMSrmm EDGRMMxx OPTION SMSTAPE operand to control the support that DFSMSrmm provides. Refer to Defining system options: OPTION for information about the SMSTAPE operand. See DFSMSrmm mapping macros for mapping macros you can use with the installation exits.

Table 1. OAM installation exits
Exit	Description
CBRUXCUA	The CBRUXCUA exit controls the return to scratch status and updates the DFSMSrmm control data set with information from the TCDB.
CBRUXEJC	The CBRUXEJC exit controls the ejection of a cartridge from a library and updates information in the DFSMSrmm control data set. You can run this exit in parallel with another copy of the exit. See Setting up parallel processing for more information.
CBRUXENT	The CBRUXENT exit controls the entry of a cartridge into a library, updates information in the DFSMSrmm control data set, and updates DFSMSrmm information in the TCDB. You can run this exit in parallel with another copy of the exit. See Setting up parallel processing for more information.
CBRUXVNL	The CBRUXVNL exit retrieves information from the DFSMSrmm control data set when a volume that is not in a tape library is needed for processing to continue.

The OAM exits that DFSMSrmm supplies call EDGLCSUX, the DFSMSrmm program that supports the OAM interface. EDGLCSUX is a callable program interface to DFSMSrmm that you can use only from the OAM installation exits.

If you do not have a license for DFSMSrmm, the DFSMSrmm OAM exits set a return code of 16, telling OAM to never call the exit again. For information on licensing, see Enabling DFSMSrmm. If you are licensed for DFSMSrmm, and you have performed some of the installation steps, but have not added EDGSSSI to the IEFSSNxx member of parmlib, or have not started the DFSMSrmm procedure, DFSMSrmm sets return code zero, allowing all OAM requests to be accepted. Once you have performed the installation steps, but do not start the DFSMSrmm subsystem, the OAM exits set a return code 8 and fail all requests.