Multiple release detection

When a RELFC macro (or equivalent C function) is processed, the z/TPF system retrieves the record and files it with a RELFC record ID (X'FC38') and diagnostic data. When a subsequent RELFC macro is issued for the same pool address and the record is retrieved again, the record ID is checked for the RELFC record ID. If the RELFC record ID is there, the record is considered to be a multiple release and the release is not performed. If the record does not have the RELFC record ID, it is filed with record ID X'FC38' and the release is performed normally.

Multiple release detection (MRD) can be processed for all RELFC macros or relfc or tpf_relfc_ext functions, or it can be restricted based on processor, record ID, and pool type. Use the ZGFSP MRD command to tailor MRD processing to fit your environment.