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Using Communication Words in Exit Routines

CA MIM exit routines use words that serve as communication pointers during processing. A communication word is a CA‑defined word of memory that CA MIM sets during an initialization and then passes unchanged for all subsequent calls of an exit routine. The routines use two types of communication words:

• A routine-specific communication word is one that is unique to a particular routine. The routine initializes this word during its initialization call.

  When a routine is reloaded, the prior value of its communication word is made available for the reinitialization call. Reloading enables the routine to either reuse the previous data area or release it from storage. The routine is responsible for maintaining any previously allocated storage.

• A global communication word is a common value that is set by the MIMINIXT exit routine and passed to all routines.

  The MIMINIXT exit routine is called once when CA MIM initializes, before any other exit routine is initialized. You can use the MIMINIXT routine to acquire and initialize a global exit communication area. For a description of the MIMINIXT exit routine, see MIMINXT Exit Routine.