Shell Programming and Scripting

username="ONE"
(
# Find all secondary groups for $username
groups -g "${username}" | tr " " "\n" | while read group_name
do
        # Find primary group of all members of each $group_name
        listusers -g "${group_name}" | awk '{print $1}'|while read member
        do
                # Look up $member in /etc/passwd and output username and group
                awk -F: '{if ($1 == member) {print $1,$4; exit}}' member=$member /etc/passwd
        done
done
# Eliminate duplicates
) | sort | uniq | while read username2 group_no2
do
        # Convert primary group number into group name
        group_name2="`awk -F: '{if ($3 == group) {print $1; exit}}' group=$group_no2 /etc/group`"
        echo "${username2} ${group_no2} ${group_name2}" > fic_results_tmp.log
done

groups

>> fic_results_tmp.log