IBM SC33-1683-02 - Manual (Page 80)

UEPIOAX
Address of I/O area existence flag byte:
UEPIOA1
I/O area exists.
For UEPCSHIP requests, the I/O area existence flag is
always off.
UEPIOA
Address of I/O area. This is the application’s IOAREA, or
DFHEDP’s IOAREA in the case of EXEC DLI. The contents
of the IOAREA can be overwritten in the exit and are
returned to the application program in the new form.
However, it should be noted that the application’s IOAREA
could be in the program’s static storage and, in this case,
should not be overwritten.
For UEPCSHIP requests, UEPIOA is always zero.
UEPUIBX
Address of UIB existence flag byte:
UEPUIB1
a UIB exists.
UEPUIB
Address of the UIB, which is mapped by DFHUIB in module
DFHDBCOP. The contents of the UIB can be overwritten in
the exit for all types of request, including UEPCSHIP. The
new contents are returned to the application or to the region
that function shipped the request.
Return codes
UERCNORM
Continue processing.
UERCPURG
Task purged during XPI call.
XPI calls
All can be used.
DL/I interface program exits
48 CICS TS for OS/390: CICS Customization Guide