IBM SC33-1683-02 - Manual (Page 78)

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: the new
contents are used when the DL/I request is processed.
However, it should be noted that IOAREAs can be in a
program’s static storage and, in this case, should not be
overwritten.
For UEPCSHIP requests, UEPIOA is always zero.
UEPPSBNX
Address of PSB existence flag byte:
UEPPSB1
A PSB exists.
UEPPSBNM
Address of an area containing the 8-character PSB name.
The contents of the area can be overwritten by the exit, for
all types of request including UEPCSHIP; the new contents
are used when the DL/I request is processed.
UEPSYSDX
Address of the SYSID existence flag byte:
UEPSYS1
A SYSID exists.
UEPSYSID
Address of an area containing the 4-character SYSID name.
The contents of the area can be overwritten by the exit, for
all types of request including UEPCSHIP; the new contents
are used when the DL/I request is processed.
Return codes
UERCNORM
Continue processing
UERCBYP
Bypass DL/I request and return
UERCPURG
Task purged during XPI call.
XPI calls
All can be used.
DL/I interface program exits
46 CICS TS for OS/390: CICS Customization Guide