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       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


       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)

       -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-

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


       /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), groupmod(8), useradd(8), userdel(8)


       Julianne Frances Haugh (jockgrrl@ix.netcom.com)




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