gpasswd

Administer group passwords and membership

TLDR

Define group administrators

$ sudo gpasswd -A [user1,user2] [group]

Set the list of group members

$ sudo gpasswd -M [user1,user2] [group]

Create a password for the named group

$ gpasswd [group]

Add a user to the named group

$ gpasswd -a [user] [group]

Remove a user from the named group

$ gpasswd -d [user] [group]

gpasswd administers /etc/group and /etc/gshadow files. It is used to add and remove users from groups, set group administrators, and manage group passwords.Group administrators (set with -A) can add or remove members without root privileges, delegating group management to trusted users. Group passwords (rarely used) allow non-members to temporarily join a group using the newgrp command.

PARAMETERS

-a, --add USER

Add user to the group

-d, --delete USER

Remove user from the group

-A, --administrators USER,...

Set list of group administrators

-M, --members USER,...

Set list of group members (replaces existing)

-r, --remove-password

Remove group password

-R, --restrict

Restrict access to group (only members can use newgrp)

INSTALL

sudo apt install passwd

sudo pacman -S shadow

sudo apk add shadow

sudo zypper install shadow

nix profile install nixpkgs#shadow

CAVEATS

The -M option replaces all group members, not appends. Use -a and -d for incremental changes. Group password usage is discouraged in favor of proper membership management. Changes take effect on next login.

HISTORY

gpasswd is part of the shadow-utils package, which provides the shadow password suite for Unix systems. The shadow system was developed in the 1980s to improve password security by moving password hashes from the world-readable /etc/passwd to the restricted /etc/shadow file.

RESOURCES

Source code