"do ... while ((NULL + 1) - 1);" -- valid C?

[Doug Gwyn]

In article <10691 at smoke.BRL.MIL> gwyn at brl.arpa (Doug Gwyn) writes:
>strchr() does not return a preprocessor macro; it returns a null macro

That was supposed to say:

strchr() does not return a preprocessor macro; it returns a null pointer ...

Our stupid news system software wouldn't let me cancel the article so
that I could send a corrected version.  I hope that this slip-up didn't
cause anybody too much confusion.

strchr(/*...*/)+1 is WRONG when strchr() returns a null pointer.