Bruce Momjian <pgman@candle.pha.pa.us> writes:
> Tom, did you implement this functionality in *printf?
> The size may be given as zero to find out how many characters are
> needed; in this case, the str argument is ignored. Sprintf() and
> vsprintf() effectively assume an infinite size.
Where do you read that? The SUS says the opposite:
If the value of n is zero on a call to snprintf(), an unspecifiedvalue less than 1 is returned.
and that's what our code implements.
regards, tom lane