Belay my last. As Roy pointed out, the bulk of the time was consumed on
umpteen printf() functions, so it is not surprising that there was little
difference in execution time between the two programs. It would be visible
if present only if the IO binding were replaced by bit setting in an array
or some other method that did not involve waiting in a queue (as I
originally suggested).

    Apologies if I misled you. It was not intentional.

Best Wishes,
Bill.

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