Linux in a Nutshell, 6th Edition

Name

passwd

Synopsis

passwd [options] [user]

Create or change a password associated with a user name. Only the owner or a privileged user may change a password. Owners need not specify their user name. Users can change their own passwords. For all other operations, you must be root.

Options

-d, --delete

Delete the password for the user’s account.

-f, --force

Force the operation. Overrides -u.

-?, --help

Display a help message describing the options. See also --usage.

-i days, --inactive=days

Set the number of days after a password has expired before the account is disabled.

-k, --keep-tokens

Keep passwords (authentication tokens) that have not expired.

-l, --lock

Lock the user’s account.

-n days, --minimum=days

Set the minimum number of days that the password is valid.

-S, --status

Print the status of the user’s password.

--stdin

Read new passwords from standard input.

-u, --unlock

Unlock the user’s account

--usage

Display a brief usage message. See also --help.

-w days, --warning=days

Set the number of days of warning users will get before their password expires.

-x days, --maximum=days

Set the maximum number of days that the password is valid.