[Toybox] add groups implementation to id.c

[Ivo van Poorten]

Hi,

Stilling getting familiar with the toybox infrastructure. Here's a
simple addition to begin with.

To discuss:

1. for 'groups username' FSF's groups prints the username and a colon
at the start of the line. The LSB does not specifically describes
that. Should we stay compatible with GNU coreutils or not?

2. FSF's groups accepts more than one username, which is not conform
the LSB's description, which states one optional user argument.

3. id is in posix/ and groups is from the LSB. If we decide to ignore
coreutils, groups could move to lsb/ and call id -Gn [user].

Regards,
Ivo
-------------- next part --------------
A non-text attachment was scrubbed...
Name: groups.diff
Type: text/x-patch
Size: 1512 bytes
Desc: not available
URL: <http://lists.landley.net/pipermail/toybox-landley.net/attachments/20130511/46d2479a/attachment-0006.bin>