# phpman > man > groupmems(8)

[GROUPMEMS(8)](https://www.chedong.com/phpMan.php/man/GROUPMEMS/8/markdown)                         System Management Commands                         [GROUPMEMS(8)](https://www.chedong.com/phpMan.php/man/GROUPMEMS/8/markdown)



## NAME
       groupmems - administer members of a user's primary group

## SYNOPSIS
       **groupmems** -a _user_name_ | -d _user_name_ | [-g _group_name_] | -l | -p

## DESCRIPTION
       The **groupmems** command allows a user to administer their 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.

## OPTIONS
       The options which apply to the **groupmems** command are:

### -a --add
           Add a 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 --delete
           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
           The superuser can specify which group membership list to modify.

### -h --help
           Display help message and exit.

### -l --list
           List the group membership list.

### -p --purge
           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.

### -R --root
           Apply changes in the _CHROOT_DIR_ directory and use the configuration files from the
           _CHROOT_DIR_ directory.

## SETUP
       The **groupmems** executable should be in mode 2710 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 2710 groupmems
                $ chown root.groups groupmems
                $ groupmems -g groups -a gk4


## CONFIGURATION
       The following configuration variables in /etc/login.defs change the behavior of this tool:

### MAX___MEMBERS___PER___GROUP (number)
           Maximum members per group entry. When the maximum is reached, a new group entry (line) is
           started in /etc/group (with the same name, same password, and same GID).

           The default value is 0, meaning that there are no limits in the number of members in a
           group.

           This feature (split group) permits to limit the length of lines in the group file. This
           is useful to make sure that lines for NIS groups are not larger than 1024 characters.

           If you need to enforce such limit, you can use 25.

           Note: split groups may not be supported by all tools (even in the Shadow toolsuite). You
           should not use this variable unless you really need it.

## FILES
       /etc/group
           Group account information.

       /etc/gshadow
           secure group account information

## SEE ALSO
       [**chfn**(1)](https://www.chedong.com/phpMan.php/man/chfn/1/markdown), [**chsh**(1)](https://www.chedong.com/phpMan.php/man/chsh/1/markdown), [**passwd**(1)](https://www.chedong.com/phpMan.php/man/passwd/1/markdown), [**groupadd**(8)](https://www.chedong.com/phpMan.php/man/groupadd/8/markdown), [**groupdel**(8)](https://www.chedong.com/phpMan.php/man/groupdel/8/markdown), [**useradd**(8)](https://www.chedong.com/phpMan.php/man/useradd/8/markdown), [**userdel**(8)](https://www.chedong.com/phpMan.php/man/userdel/8/markdown), [**usermod**(8)](https://www.chedong.com/phpMan.php/man/usermod/8/markdown).



shadow-utils 4.8.1                           02/06/2024                                 [GROUPMEMS(8)](https://www.chedong.com/phpMan.php/man/GROUPMEMS/8/markdown)