Caller parameter lists

In addition to the DSECTs DFHUEPAR and DFHUERTR, the inclusion of DFHUEXIT TYPE=RM in the task-related user exit program provides some field definitions that are specific to the caller of the task-related user exit. The calling program's parameter list is normally addressed by R1 in the calling program's RSA. This RSA is addressed by field UEPHMSA of DFHUEPAR. These parameters are described in this section.

Application program parameters

If the caller is an application program, the format and addressing of its parameter list are decided locally.

CICS SPI parameters

If you enable your task-related exit program with the SPI option of the EXEC CICS ENABLE PROGRAM command, the exit program can be started when you use the EXEC CICS INQUIRE EXITPROGRAM command or on which the CONNECTST or QUALIFIER option is specified.

Use the INQUIRE EXITPROGRAM command to query whether the exit program is connected to its resource manager, and its entryname qualifier. For information about the INQUIRE EXITPROGRAM command, see INQUIRE EXITPROGRAM.

The CICS® SPI parameter list contains two entries:

Parameter 1

The address of a 1- byte output field, which your task-related exit program uses to indicate whether it is connected to its external resource manager. The equated return code values are as follows:

UERTCONN: (X'80') The exit is connected to its resource manager.
UERTNCONN: (X'40') The exit is not connected to its resource manager.

Parameter 2

The address of an 8- character output field, in which your task-related exit program returns the qualifier of the external resource manager, if known. See the UEPRMQUA parameter in DFHUEPAR for more information about qualifier names.

CICS switch application environment parameters

There are no explicit parameters when CICS calls a task-related user exit for a switch application environment call.

Before CICS stops using an open TCB, the TRUE is run on this TCB and the TRUE must release any resources associated with this TCB. The CICS transaction may continue and the TRUE may be called again on a different open TCB, and may then associate its resources with this new open TCB.

For example, a TRUE enabled as CONCURRENCY(REQUIRED) API(CICSAPI) and called from a CICS Java™ application will run on a T8 open TCB. When the Java application completes, if the TRUE has expressed interest in switch_application_environment events, the TRUE is called to release its resources from the T8 open TCB. For a subsequent end of task syncpoint, the TRUE will be invoked on an L8 TCB and can associate its resources with the L8 TCB to execute its syncpoint processing