id confusion

[Bauke Jan Douma]

Hi,

I wonder if, in the following session, the responses as given by 'id'
are correct and as intended (not regarding the numbers -- 1001 and the
others are correct), and if they wash with the manpage, specifically the
invocations with -gG, -ugG and -r.

To me it would seen g and G are mutually exclusive. But then what is
meant by the comment for option '-r' in the manpage?
A bit confusing, as are the nonzero-exit responses. And why doesn't id -r
succeed?

bjd

here's the session:


address@hidden:~$ id --version
id (GNU coreutils) 6.10
Copyright (C) 2008 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

Written by Arnold Robbins and David MacKenzie.

address@hidden:~$ id
uid=1001(piglet) gid=1001(piglet) groups=4(adm),20(dialout),21(fax),24(cdrom),
25(floppy),26(tape),29(audio),30(dip),44(video),46(plugdev),105(scanner),
107(fuse),1001(piglet)

address@hidden:~$ id -g
1001

address@hidden:~$ id -G
1001 4 20 21 24 25 26 29 30 44 46 105 107

address@hidden:~$ id -gG
id: cannot print "only" of more than one choice

address@hidden:~$ id -ugG
id: cannot print "only" of more than one choice

address@hidden:~$ id -r
id: cannot print only names or real IDs in default format


from the manpage:

       -r, --real
              print the real ID instead of the effective ID, with -ugG