On 27/05/2022 14:50, Jens Gustedt wrote:

> AFAIR is `ENOTSUP` only in POSIX but not in C? If so, this would need to
> be added to the clause for `errno`.

The proposed normative wording changes in the next revision of my paper
do include adding ENOTSUP. I just didn't paste that in my email for brevity.

I also didn't paste all the newly added permutations of letters to
section 7.21.5.3.3, which has become quite long now. The next release of
POSIX, incidentally, considerably loosens the permitted ordering of
letters for fopen. It saves having to spell out all the combinations in
the specification.

Niall