Using the JRNAD Exit with Shared Resources

VSAM takes the JRNAD exit for the following reasons when the exit is associated with a data set whose ACB has MACRF=LSR or GSR:

A data or index control interval buffer has been modified and is about to be written.
A physical error occurred. VSAM takes the JRNAD exit first—your routine can direct VSAM to bypass the error and continue processing or to terminate the request that occasioned the error and proceed with error processing.
A control interval or a control area is about to be split for a key-sequenced data set or variable-length RRDS. Your routine can cancel the request for the split and leave VSAM. An example of using the JRNAD exit for this purpose is given in JRNAD Exit Routine to Journalize Transactions.

See JRNAD Exit Routine to Journalize Transactions for information describing the contents of the registers when VSAM exits to the JRNAD routine, and the fields in the parameter list pointed to by register 1.