Re: Bug#249177: coreutils: chown is not POSIXLY_CORRECT even when the variable is set

[Paul Eggert]

>>   For the BSD -H/-L/-P options, which control file tree walking:
>>
>>     -P = --walk=physical
>>     -H = --walk=hybrid  (I have no idea what -H originally stood for.)
>>     -L = --walk=logical

As a minor point I'm now thinking that it might be clearer to make
these options operands of --recursive instead, e.g.,
--recursive=physical.  This is because -P/-H/-L makes no sense without
-R.


>> * Minor suggestion: "chown : file" should invoke chown with uid and
>>   gid both set to -1, so that the file ownership and group doesn't
>>   change but the setuid/setgid bits are cleared (and perhaps ACLs are
>>   removed).  This might be useful.
>
> POSIX seems to require owner[:group].
> Is it compliant to accept `:'?

Yes, as an upward-compatible extension.  GNU chown already accepts
":group" as an extension, for example.