Switch to SpeakEasy.net DSL

The Modular Manual Browser

Home Page
Manual: (Debian-3.1)
Apropos / Subsearch:
optional field

USERMOD(8)                  System Manager's Manual                 USERMOD(8)

       usermod - Modify a user account

       usermod [-c comment] [-d home_dir [-m]]
               [-e expire_date] [-f inactive_days]
               [-g initial_group] [-G group [,...]]
               [-l login_name] [-p passwd]
               [-s shell] [-u uid [-o]] [-L|-U] login

       The  usermod  command  modifies the system account files to reflect the
       changes that are specified on the  command  line.   The  options  which
       apply to the usermod command are:

       -c comment
              The  new value of the user's password file comment field.  It is
              normally modified using the chfn(1) utility.

       -d home_dir
              The user's new login directory.  If the -m option is  given  the
              contents  of the current home directory will be moved to the new
              home directory, which is created if it does not already exist.

       -e expire_date
              The date on which the user account will be disabled.   The  date
              is specified in the format YYYY-MM-DD.

       -f inactive_days
              The number of days after a password expires until the account is
              permanently disabled.  A value of 0 disables the account as soon
              as the password has expired, and a value of -1 disables the fea-
              ture.  The default value is -1.

       -g initial_group
              The group name or number of the user's new initial login  group.
              The  group  name  must  exist.   A group number must refer to an
              already existing group.  The default group number is 1.

       -G group,[...]
              A list of supplementary groups which the user is also  a  member
              of.   Each  group is separated from the next by a comma, with no
              intervening whitespace.  The groups  are  subject  to  the  same
              restrictions as the group given with the -g option.  If the user
              is currently a member of a group which is not listed,  the  user
              will be removed from the group

       -l login_name
              The  name  of the user will be changed from login to login_name.
              Nothing else is changed.  In particular, the user's home  direc-
              tory  name  should  probably be changed to reflect the new login

       -o     When used with the -r option, this option allows to  change  the
              user ID to a non-unique value.

       -p passwd
              The encrypted password, as returned by crypt(3).

       -s shell
              The  name  of the user's new login shell.  Setting this field to
              blank causes the system to select the default login shell.

       -u uid The numerical value of  the  user's  ID.   This  value  must  be
              unique,  unless  the  -o option is used.  The value must be non-
              negative.  Values between 0 and 99 are  typically  reserved  for
              system  accounts.   Any  files which the user owns and which are
              located in the directory tree rooted at the user's  home  direc-
              tory  will  have  the file user ID changed automatically.  Files
              outside of the user's home directory must be altered manually.

       -L     Lock a user's password.   This  puts  a  '!'  in  front  of  the
              encrypted  password,  effectively  disabling  the password.  You
              can't use this option with -p or -U.

       -o     Allows changing the user ID to a non-unique value when used with
              -u option.

       -U     Unlock  a user's password.  This removes the '!' in front of the
              encrypted password.  You can't use this option with -p or -L.

       usermod will not allow you to change the name of a user who  is  logged
       in.   You  must  make  certain that the named user is not executing any
       processes when this command is being executed if the  user's  numerical
       user  ID  is  being  changed.  You must change the owner of any crontab
       files manually.  You must change the owner of  any  at  jobs  manually.
       You must make any changes involving NIS on the NIS server.

       /etc/passwd - user account information
       /etc/shadow - secure user account information
       /etc/group - group information

       chfn(1), chsh(1), passwd(1), crypt(3), groupadd(8), groupdel(8), group-
       mod(8), useradd(8), userdel(8)

       Julianne Frances Haugh (jockgrrlATix.com)