I saved the code as gpu.pl and ran it for some users: 
$ gpu.pl root
0
2
3
4
5
20
31
0

$ gpu.pl rvtol

$ id -Gn rvtol
user

[download]
With root, group 0 is reported twice. With rvtol, group user (30) isn't reported.

-- 
Regards, Ruud

In reply to Re^2: Fetching groups a user is in by druud
in thread Fetching groups a user is in by belg4mit

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