]> Julianne Frances Haugh Creation, 1991 Thomas Kłoczko kloczek@pld.org.pl shadow-utils maintainer, 2000 - 2007 Nicolas François nicolas.francois@centraliens.net shadow-utils maintainer, 2007 - now groupmod 8 System Management Commands shadow-utils &SHADOW_UTILS_VERSION; groupmod modify a group definition on the system groupmod options GROUP The groupmod command modifies the definition of the specified GROUP by modifying the appropriate entry in the group database. The options which apply to the groupmod command are: -a, --append GID If group members are specified with -U, append them to the existing member list, rather than replacing it. -g, --gid GID The group ID of the given GROUP will be changed to GID. The value of GID must be a non-negative decimal integer. This value must be unique, unless the -o option is used. Users who use the group as primary group will be updated to keep the group as their primary group. Any files that have the old group ID and must continue to belong to GROUP, must have their group ID changed manually. No checks will be performed with regard to the GID_MIN, GID_MAX, SYS_GID_MIN, or SYS_GID_MAX from /etc/login.defs. -h, --help Display help message and exit. -n, --new-name NEW_GROUP The name of the group will be changed from GROUP to NEW_GROUP name. -o, --non-unique When used with the -g option, allow to change the group GID to a non-unique value. -p, --password PASSWORD The encrypted password, as returned by crypt3 . Note: This option is not recommended because the password (or encrypted password) will be visible by users listing the processes. You should make sure the password respects the system's password policy. -R, --root CHROOT_DIR Apply changes in the CHROOT_DIR directory and use the configuration files from the CHROOT_DIR directory. Only absolute paths are supported. -P, --prefix PREFIX_DIR Apply changes in the PREFIX_DIR directory and use the configuration files from the PREFIX_DIR directory. This option does not chroot and is intended for preparing a cross-compilation target. Some limitations: NIS and LDAP users/groups are not verified. PAM authentication is using the host files. No SELINUX support. -U, --users A list of usernames to add as members of the group. The default behavior (if the -g, -N, and -U options are not specified) is defined by the USERGROUPS_ENAB variable in /etc/login.defs. 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. /etc/login.defs Shadow password suite configuration. /etc/passwd User account information. The groupmod command exits with the following values: 0 E_SUCCESS: success 2 E_USAGE: invalid command syntax 3 E_BAD_ARG: invalid argument to option 4 E_GID_IN_USE: group id already in use 6 E_NOTFOUND: specified group doesn't exist 9 E_NAME_IN_USE: group name already in use 10 E_GRP_UPDATE: can't update group file 11 E_CLEANUP_SERVICE: can't setup cleanup service 12 E_PAM_USERNAME: can't determine your username for use with pam 13 E_PAM_ERROR: pam returned an error, see syslog facility id groupmod for the PAM error message chfn1 , chsh1 , passwd1 , gpasswd8 , groupadd8 , groupdel8 , login.defs5 , useradd8 , userdel8 , usermod8 .