Morning,
Den 2025-12-09 kl. 03:49, skrev Robert Elz:
Date: Mon, 8 Dec 2025 20:45:00 +0100
From: Anders Magnusson<[email protected]>
Message-ID:<[email protected]>
| I just stumbled over something which may be a bug in scanf()...?
| This example is in C99 7.19.6.2 clause 20.
Yes, but nowhere there does it say what the result should be in the
case that you give, and I think you're arriving at an incorrect
conclusion.
Sorry, but I think that is very clear? The input scanning should stop
whenever something unwanted is read.
And as you noticed in the followup mail; this was an example from the
standard which was what I was referring to :-)
Also, as you note it should accept whatever strtod() do, _but_: C99 note
242 (C23 note 348) says:
"fscanf pushes back at most one input character onto the input stream.
Therefore, some sequences
that are acceptable to strtod, strtol, etc., are unacceptable to fscanf.".
which is what should happen here (and the reason "100ergs" should fail
for %f in *scanf()).
When reading the 'r' the scanning for %f fails and it returns. As the
standard says...?
-- Ragge
