noop comparator for qsort

From: Trent Buck (NOSPAMfubarbaz_at_bigpond.com)
Date: 11/14/04 

Date: Sun, 14 Nov 2004 08:15:15 GMT

The fourth argument is a comparator that returns `an integer less than,
equal to, or greater than zero' depending on the ordering of its
arguments.

If I don't care about the order and simply want qsort() to run as
quickly as possible, how should the comparator be defined?

If qsort were stable, the following would be best:

        int
        compare (void *x, void *y)
        {
          return 0;
        }

...is this still true for a possibly non-stable qsort()?

-trent

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