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Rules for Coding Exit Routines

Follow these rules when coding CA MIA exit routines:

• Exits for CA MIA and other product components are invoked using a standard parameter list, pointed to by register 1.
• Assume standard linkage and register saving conventions.
• Preserve all registers except 0, 1, and 15.
• Make the TPCEDLXT, TPCSRMXT, and TPCRECXT routines reentrant. Because these routines do not hold local or CMS locks, which enable them to issue SVCs, multiple allocation requests may be invoked in parallel.
• CA MIM moves the exit routines above the 16-megabyte line if the RMODE value for the routines is 31.
• Assemble and link the routines into the authorized load library that contains the CA MIM load modules. The sample member named ASMEXIT in the CAI.CBTDJCL data set contains JCL that you can use to assemble and link-edit exit routines.