Programming Considerations

The following programming considerations apply to the batch override exit:

The name of this exit must be IGW8PNRU.
The exit must be loadable from any system that might do peer recovery for another system.
The IGW8PNRU module is loaded by DFSMStvs and, therefore, must reside in LINKLIB or LPALIB. If the load fails, DFSMStvs issues a message.
If it does not find the batch override exit, DFSMStvs shunts any UR with a pending backout for a data set that was accessed through PERMITNONRLSUPDATE.
If your installation needs to fix a code error or enhance the function of the exit, you need to restart DFSMStvs to enable the new exit.
The exit can issue SVC instructions.

DFSMStvs establishes an ESTAE recovery environment before calling the exit to protect the RLS address space from failures in the exit. If the exit fails or an attempt to invoke it fails, the UR is shunted. A dump is taken, and the exit is disabled until the next DFSMStvs restart, but the server is not recycled. If the exit abnormally ended, it might result in a dump with a title like this:

DUMP  TITLE=COMPID=?????,CSECT=????????+FFFF,DATE=????????,MAINT
          ID=????????,ABND=0C4,RC=00000000,RSN=00000004

If this happens, investigate why the exit abended.

Recommendation: It is possible for this exit to perform other processing, but IBM strongly recommends that the exit not attempt to update any recoverable resources.

When your IGW8PNRU routine completes processing, return to your main program as described in Return to a Main Program.