The assembler user exit, when invoked for initialization, might return a list of abend codes that are to be percolated by Language Environment. The list of abend codes is contained in the CEEAUE_A_AB_CODES field of the assembler user exit interface. For more information, see CEEBXITA assembler user exit interface.

On non-CICS systems, this list is contained in the CEEAUE_A_AB_CODES field of the assembler user exit interface. (See CEEBXITA assembler user exit interface.) Both system abends and user abends can be specified in this list. The abend percolation list specified in the assembler user exit applies to all threads in the enclave.

When TRAP(ON) is in effect, and the abend code is in the CEEAUE_A_AB_CODES list, Language Environment percolates the abend. Normal Language Environment condition handling is never invoked to handle these abends. This feature is useful when you do not want Language Environment condition handling to intervene for certain abends, such as when IMS™ issues a user abend code 777.

When TRAP(OFF) is specified and there is a program interrupt, the user exit for termination is not driven.