A JRNAD exit routine can be provided to record transactions against
a data set, to keep track of changes in the RBAs of records, and to
monitor control interval splits. It is only available for VSAM shared
resource buffering. When using the JRNAD exit routine with compressed
data sets, all RBAs and data length values returned represent compressed
data. For shared resources, you can use a JRNAD exit routine to deny
a request for a control interval split. VSAM takes the JRNAD exit
each time one of the following occurs:
- The processing program issues a GET, PUT, or ERASE
- Data is shifted right or left in a control interval or is moved
to another control interval to accommodate a records being deleted,
inserted, shortened, or lengthened
- An I/O error occurs
- An I/O completion occurs
- A shared or nonshared request is received
- The buffer contents are to be changed.
Restriction: The JRNAD exit is not supported
by RLS.