DFSMShsm takes predetermined actions when it detects certain error conditions. You use the TRAP command to alter DFSMShsm's actions based on your installation’s needs. You cannot use TRAP to alter any error conditions for which DFSMShsm issues an abend or a shutdown. Instead, as the issuer of the TRAP command, you may request that DFSMShsm take one of the following actions in response to the specified error condition:

• Abnormally end the task when the error occurs. After the abnormal end, DFSMShsm produces an abnormal end dump (ABEND).
• Write the error in the command activity log (LOG).
• Remove a previous trap (OFF).
• Perform a snap dump (SNAP).

DFSMShsm automatically shuts down because of recurring trap conditions. For example, DFSMShsm automatically shuts down after 200 occurrences of the same error code in the same module under one of the following conditions:

• Automatic traps: 200 occurrences of the same error code in the same module with an option of ABEND or SNAP.
• TRAP command issued with the SNAP option: 200 occurrences of the same error code in the same module with an option of ABEND or SNAP.
• TRAP command issued with the ABEND option: 200 occurrences of the same error code in the same module with any option except FATAL.

Table 1 shows which ARCERP options can be altered by a TRAP option. In general:

• You can alter only the ARCERP options of LOG, DEBUG, and SNAP by a TRAP option.
• You cannot alter the ARCERP options of FATAL, ABEND, and ABEND/NODUMP by a TRAP option.