Exit XXDTO
Exit XXDTO is invoked by an alternate CICS® when it performs takeover under the following conditions:
- The active and alternate CICS systems are in different z/OS® images, perhaps in different processors.
- The active CICS was connected to, or trying to connect to, a DBCTL subsystem. (This does not include disconnecting from one DBCTL and reconnecting to another.)
- The takeover was not initiated by the XXDFB exit, or the takeover was initiated by XXDFB but the active system reestablished a DBCTL connection before takeover occurred and XXDTO was driven for a new DBCTL takeover decision.
Exit-specific parameters
- UEPDBXR
- Address of CICS XRF information for use with DBCTL. The CICS XRF information can be mapped using the DSECT DFHDXUEP.
Return codes
- UERCNOAC
- Take no action.
- UERCSWCH
- Switch to the alternate DBCTL.
- UERCABNO
- Abend CICS without a dump.
- UERCABDU
- Abend CICS with a dump.
The return code UERCNORM is not available for use at this exit point.
XPI calls
The following commands must not be used:
- INQUIRE_MONITORING_DATA
- MONITOR
- TRANSACTION_DUMP
- WRITE_JOURNAL_DATA.
API and SPI calls
None can be used.