Programs declaring interrupt routines

If your program declares interrupt routines with ABNEXIT, HNDEXT, or their z/OS® equivalents read this section.

Remember that some interrupt routines are not automatically cleared by CMS at end of command. ABNEXIT is one of these. If you are in a debugging session and your program has declared an ABNEXIT routine, if you quit from IDF through PF3 before your program explicitly clears the exit routine, the exit routine remains in effect even when your program is no longer in memory. The next time you run a program or invoke IDF for another debugging session, a system abend is most likely, after which you need to re-IPL CMS.

It is safest if you re-IPL CMS after a debugging session where exit routines were tested. The results after IDF completes are unpredictable.