XFCLDEL global user exit

XFCLDEL is invoked when backing out a unit of work that performed a write operation to a VSAM ESDS, or a BDAM data set.

XFCBOVER global user exit

XFCBOVER is invoked whenever CICS is about to decide not to backout an uncommitted update, because the record could have been updated by a non-RLS batch program.

This situation can occur after a batch program has opened a data set, even though it has retained locks, by overriding the RLS data set protection.

XFCBOUT global user exit

XFCBOUT is invoked when CICS is about to backout a file update.

Coding transaction backout exits

You have access to all CICS services, except terminal control services, during exit execution.

About this task

However, consider the following restrictions:

vThe exit programs must be written in assembler code.

vThey must be quasi-reentrant. They may use the exit programming interface (XPI) and issue EXEC CICS commands.

vIf an exit program acquires an area as a result of a file control request, it is the responsibility of the exit to release that area.

vAn exit must not attempt to make any file control requests to a file referring to a VSAM data set opened in non-RLS mode with a string number of 1, unless no action is specified for that file during the initialization exit.

vTask-chained storage acquired in an exit should be released by the exit as soon as its contents are no longer needed.

vIf an exit is not used, the default actions are taken.

vWe strongly recommend that emergency restart global user exits do not change any recoverable resource. If you do try to use temporary storage, transient data, or file control, these resource managers may also be in a state of recovery. Access to these services will, therefore, at best cause serialization of the recovery tasks and, at worst, cause a deadlock.

162CICS TS for z/OS 4.1: Recovery and Restart Guide

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IBM SC34-7012-01 manual Xfcldel global user exit, Xfcbover global user exit, Xfcbout global user exit