POSIX conformance document

[Bruno Haible <bruno@clisp.org>]

POSIX [1] specifies that conforming implementations shall come with a
"conformance document" that describes "implementation-defined" characteristics
[2]. Two such example conformance documents are [3], [4].

For Linux (or any Linux distro), I cannot find such a document on the web.

Is such a document only considered useful for business/marketing purposes?
Isn't there some value in it also for regular users and developers?

Will there be some effort to create such a document for the upcoming
POSIX.1-2024 standard, for Linux and the GNU libraries and tools?

I'm asking because I've collected the answers for all *gettext() functions
and the msgfmt and xgettext programs (that will be part of this new POSIX),
but I don't know where to best document them. Likely in the manual of
GNU libc and GNU gettext, right?

         Bruno

[1] https://en.wikipedia.org/wiki/POSIX
[2] https://pubs.opengroup.org/onlinepubs/9699919799.2018edition/basedefs/V1_chap02.html
[3] https://empyreal96.github.io/nt-info-depot/SourceLevel/base/subsys/posix/pcd.doc
[4] https://www.qnx.com/developers/docs/6.5.0SP1.update/com.qnx.doc.neutrino_prog/posix_conformance.html