Re: Improve getopt error strings?

[Paul Eggert]

Thanks for the suggestion. That part of Gnulib is maintained by glibc, 
so bug reports should be sent there.

POSIX mildly suggests the wordings of the first two strings you mention, 
here:

https://pubs.opengroup.org/onlinepubs/9799919799/utilities/getopts.html#tag_20_53_18

Although the wordings are not required, the hint in the POSIX rationale 
is that some downstream programs might wrongly expect them.