This directory of Linux commands is from Linux in a Nutshell, 5th Edition.
Click on any of the 687 commands below to get a description and list of available options. All links in the command summaries point to the online version of the book on Safari Bookshelf.
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passwd
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 any other operation, you must be root.
Options
Delete the password for the user's account.
Force the operation. Overrides -u.
Display a help message describing the options. See also --usage.
Set the number of days after a password has expired before the account is disabled.
Keep passwords (authentication tokens) that have not expired.
Lock the user's account.
Set the minimum number of days that the password is valid.
Print the status of the user's password.
Read new passwords from standard input.
Unlock the user's account
Display a brief usage message. See also --help.
Set the number of days of warning users will get before their password expires.
Set the maximum number of days that the password is valid.
