To assist in the diagnosis of faults in a CICS® system, the trace domain passes information to the exit in a parameter list addressed by register 1. A DSECT (DFHTRADS) is supplied for this list, which contains the addresses of:
The DSECT also contains EQU statements for use in setting the return-action flag byte.
The exit can look at data from the current trace entry to determine whether or not the problem under investigation has appeared. It can also look at the TCA of the current task, and the CSA. The DSECTs for these areas are included in the skeleton source.
The CSA address is zero for invocations of DFHTRAP early in initialization, before the CSA is acquired.