Which method reliably resets the alert flag between batch steps in COBOL?

Question

COBOL programs often centralize NOTIFY calls in a single paragraph and control emission with a flag variable. The language specification, however, does not define how that flag should be cleared after each batch step, leaving the reset behavior implementation‑specific.

Because NOTIFY output can be buffered differently in batch versus interactive runs, an uncleared flag may cause duplicate or missed alerts, especially on legacy compilers that treat condition‑numbers inconsistently.

What flag‑reset strategy works consistently across both execution modes? Does any compiler provide a built‑in mechanism for automatic flag clearing? Are there documented patterns that avoid manual flag management altogether?

Tasadduq Burney · Answer

Use an explicit MOVE 0 to the flag (or SET condition-name to FALSE) at the end of the alert paragraph before the next batch step. This ensures the flag is cleared consistently whether the program runs interactively or as part of a batch job.

Confirmed facts:

Define the alert flag in working‑storage (e.g., 01 ALERT-FLAG PIC X VALUE '0').
After the NOTIFY paragraph, execute MOVE 0 TO ALERT-FLAG.
If each batch step is a separate program, pass the flag value via JCL PARM, a common file, or other external storage; otherwise keep the same program active.
Verify by running a minimal program that sets the flag, performs the alert, resets it, and repeats the alert in both batch JCL and interactive modes.
Ask: Does each batch step invoke a separate COBOL program or continue execution within the same run unit?

Which method reliably resets the alert flag between batch steps in COBOL?

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