Re: scanf "%%" and whitespace

["Clive D.W. Feather" <clive@xxxxxxxxx>]

Geoff Clare said:
> As far as I can see, the descriptions of scanf() in SUSv3 and C99
> require a %% in the format to consume any whitespace characters that
> precede a % in the input.

I agree it's what the C99 Standard requires.

> Is this intentional, or is it a defect in C99?

I can see arguments either way. On the one hand, %% was intended to be an
escape code for a single %. On the other hand, it's always been specified
as a conversion and not like a non-white-space character in the format.

My own inclination would be to rewrite C99 to make %% be an escape sequence
rather than a strangely-behaved conversion and have it not consume any
whitespace. But you'll have to go to WG14 for a formal decision.

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