User exception trace entries

The EXCEPTION option on the EXEC CICS ENTER TRACENUM command enables user programs to write a trace entry to the trace destinations, even when the main user trace flag is off. User exception trace entries are always written to the internal trace table (even if internal tracing is set off), but are written to other destinations only if they are active.

The user exception trace entries CICS® writes are identified by the character string *EXCU in any formatted trace output produced by CICS utility programs. For example, an application program exception trace entry generated by an EXEC CICS ENTER TRACENUM() EXCEPTION command appears in formatted trace output as:
USER *EXCU - APPLICATION-PROGRAM-EXCEPTION
If you use the exit programming interface (XPI) trace control function to write user trace entries, you can use the DATA1 block descriptor to indicate whether the entry is an exception trace entry. Enter the literal ‘USEREXC’ in the DATA1 field on the DFHTRPTX TRACE_PUT call to identify an exception trace entry. This is interpreted by the trace formatting utility program as follows:
USER *EXCU - USER-EXIT-PROGRAM-EXCEPTION

See The user exit programming interface (XPI) for programming information about XPI trace control function.