Bug in "id"

[Serge Wroclawski]

Hello there :)

There's a bug in "id" version (as reported by --version):
id (GNU sh-utils) 1.16

This version's man page, info page and --help says:
  -G, --groups    print only the supplementary groups

Yet this behavior is not what I get.
I get the primary group when I use this option.

This is a bug, IMHO.

This behavoir exists on Red Hat Linux and Debian/GNU Linux (of various
versions of both).

Please fix or advise me what more info to give you.

- Serge Wroclawski