usermod

 


USERMOD(8)                                             USERMOD(8)



NAME
       usermod - Modify a user account

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

DESCRIPTION
       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  dis­
              abled.   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 feature.
              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  particu­
              lar, the user's home directory name should probably
              be changed to reflect the new login name.

       -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  automati­
              cally.   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.

       -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.

CAVEATS
       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  manu­
       ally.   You must make any changes involving NIS on the NIS
       server.

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

SEE ALSO
       chfn(1),  chsh(1),  crypt(3),  groupadd(8),   groupdel(8),
       groupmod(8), passwd(1), useradd(8), userdel(8)

AUTHOR
       Julianne Frances Haugh (jfh@austin.ibm.com)



                                                       USERMOD(8)