IBM SC33-1683-02 - Manual (Page 101)

UEPRSA
Address of the application’s register save area. This contains the
contents of the registers at the point when the program issued the
EXEC CICS command.
Return codes
UERCNORM
Continue processing.
UERCPURG
Task purged during XPI call.
XPI calls
All can be used.
EXEC interface program exits
Chapter 1. Global user exit programs 69