IBM SC33-1683-02 - Manual (Page 136)

Return codes
UERCNORM
Continue processing.
UERCPURG
Task purged during XPI call.
XPI calls
All can be used.
API and SPI calls
All can be used.
Notes:
1. Take care when issuing recursive commands not to cause a loop. For example,
it is your responsibility to avoid entering a loop when a file control request is
issued from the XFCSREQC exit. Use of the recursion counter UEPRECUR is
recommended.
2. Exit programs that issue EXEC CICS commands must first address the EIB.
See “Using CICS services” on page 5.
3. Exit programs that issue EXEC CICS commands, and that use the DFHEIENT
macro, should use the DFHEIRET macro to set a return code and return to
CICS. See “Returning values to CICS” on page 10.
file control file state program exits
104 CICS TS for OS/390: CICS Customization Guide