]> groupmems 8 System Management Commands groupmems administer members of a user's primary group groupmems -a user_name -d user_name -g group_name -l -p The groupmems command allows a user to administer his/her own group membership list without the requirement of superuser privileges. The groupmems utility is for systems that configure its users to be in their own name sake primary group (i.e., guest / guest). Only the superuser, as administrator, can use groupmems to alter the memberships of other groups. The options which apply to the groupmems command are: -a user_name Add a new user to the group membership list. If the /etc/gshadow file exist, and the group has no entry in the /etc/gshadow file, a new entry will be created. -d user_name Delete a user from the group membership list. If the /etc/gshadow file exist, the user will be removed from the list of members and administrators of the group. If the /etc/gshadow file exist, and the group has no entry in the /etc/gshadow file, a new entry will be created. -g group_name The superuser can specify which group membership list to modify. -l List the group membership list. -p Purge all users from the group membership list. If the /etc/gshadow file exist, and the group has no entry in the /etc/gshadow file, a new entry will be created. The groupmems executable should be in mode 2770 as user root and in group groups. The system administrator can add users to group groups to allow or disallow them using the groupmems utility to manage their own group membership list. $ groupadd -r groups $ chmod 2770 groupmems $ chown root.groups groupmems $ groupmems -g groups -a gk4 The following configuration variables in /etc/login.defs change the behavior of this tool: &MAX_MEMBERS_PER_GROUP; /etc/group Group account information. /etc/gshadow secure group account information chfn1 , chsh1 , passwd1 , groupadd8 , groupdel8 , useradd8 , userdel8 , usermod8 .