Data sets that are used for transient data queues can be
intrapartition or extrapartition. The transient data intrapartition
data set is a VSAM entry-sequenced data set (ESDS) that is used for
queuing messages and data within the CICS® region.
Transient data extrapartition data sets are sequential files, normally
on disk or tape; you can use the queue to send and receive data outside
the CICS region.
About this task
Messages or other data are addressed to a symbolic queue that you define as either intrapartition
or extrapartition using the CEDA transaction. The queues can be used as indirect destinations to
route messages or data to other queues. System messages that CICS produces are commonly sent to transient data queues, either intrapartition or
extrapartition.
Procedure
- Define all of the queues that CICS uses in your CICS region.
Although the omission of any of the queues does not cause a CICS failure, you lose important
information about your CICS region
if CICS cannot write its data
to the required queue.
- Use the sample definitions in group DFHDCTG to define
the required queues.
- Take a backup copy of the changes that you made to DFHDCTG.
When maintenance is applied, the DFHDCTG group might be refreshed,
overwriting your changes. Taking a backup avoids this problem.
- Define the intrapartition data set using job control statements.
- Define the extrapartition data sets using job control statements.
- To print CICS system
messages on a local printer as they occur, use the transient data
write-to-terminal sample program, DFH$TDWT.
This sample
program is supplied with the CICS in CICSTS56.CICS.SDFHLOAD
and the assembler source is in CICSTS56.CICS.SDFHSAMP.