User exit parameter lists
When a task-related user exit is invoked, the CICS management module that
handles task-related user exits provides the exit with a parameter list. The address
of this parameter list is passed in register 1. The list contains the following
information:
vThe identity of the caller
vAddresses and sizes of any work areas that are available to the task-related user
exit program
vThe address of the register save area of the caller
vThe address of an EXEC interface block (EIB) that is for use by the task-related
user exit program during this invocation
vThe address of the identifier of the current unit of recovery
vThe address of the schedule flag word
vThe address of the kernel stack entry
vThe address of the APPC unit of work (UOW) identifier
vThe address of the user security block flag
vThe address of the user security block
vThe address of the resource manager qualifier name
vThe address of the resource manager’s “single-update” and “read-only” indicator
byte
vThe address of the caller’s AMODE indicator byte
vThe address of the application’s DATALOCand TASKDATAKEYindicator byte
vThe address of the performance block token
vThe address of a trace flag.
Toenable your exit program to access this parameter list, you must include in it the
macro:
DFHUEXIT TYPE=RM
The DFHUEXIT TYPE=RM macro causes the assembler to create the storage
definitions (DSECTs)DFHUEPAR and DFHUERTR. If you want your task-related
user exit to be able to format screens for EDF,you must include in it the macro:
DFHUEXIT TYPE=RM,DSECT=EDF
This causes the assembler to create the UEPEDFRM DSECT,which is described in
“CICS EDF build parameters” on page261. All of the user exit parameter lists are
summarized in Figure 7 on page 264.
The format and the purpose of these definitions are described below.

DFHUEPAR

DFHUEPAR gives you the following symbolic names for address parameters:
UEPEXN
Address of the function definition, which tells the task-related user exit
program why it is being called. See “DFHUERTR (the function definition)”
on page 257 for more details.
UEPGAA
Address of the global work area requested in the EXEC CICS ENABLE
the task-related user exit program
Chapter2. Task-related user exit programs 253