usermod(1M) UNIX System V(Essential Utilities) usermod(1M)
NAME
usermod - modify a user's login information on the system
SYNOPSIS
/usr/sbin/usermod [-u uid [-o] [-g group] [-G group[,group...]] [-d dir [-m]]
[-s shell] [-c comment] [-l new_logname] [-f inactive] [-e expire] login
DESCRIPTION
The usermod command modifies a user's login definition on the system. It
changes the definition of the specified login and makes the appropriate
login-related system file and file system changes.
The system file entries created with this command have a limit of 512
characters per line. Specifying long arguments to several options may
exceed this limit.
The following options are available:
-u uid New UID for the user. It must be a non-negative decimal
integer below MAXUID as defined in <param.h>.
-o This option allows the specified UID to be duplicated (non-
unique).
-g group An existing group's integer ID or character-string name. It
redefines the user's primary group membership.
-G group An existing group's integer "ID" "," or character string
name. It redefines the user's supplementary group
membership. Duplicates between group with the -g and -G
options are ignored. No more than NGROUPSUMAX groups may be
specified as defined in <param.h>.
-d dir The new home directory of the user. It defaults to
base_dir/login, where base_dir is the base directory for new
login home directories, and login is the new login.
-m Move the user's home directory to the new directory specified
with the -d option. If the directory already exists, it must
have permissions read/write/execute by group, where group is
the user's primary group.
-s shell Full pathname of the program that is used as the user's shell
on login. The value of shell must be a valid executable
file.
-c comment Any text string. It is generally a short description of the
login, and is currently used as the field for the user's full
name. This information is stored in the user's /etc/passwd
entry.
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usermod(1M) UNIX System V(Essential Utilities) usermod(1M)
-l new_logname
A string of printable characters that specifies the new login
name for the user. It may not contain a colon (:) or a
newline (\n).
-e expire The date on which a login can no longer be used; after this
date, no user will be able to access this login. (This
option is useful for creating temporary logins.) You may
type the value of the argument expire (which is a date) in
any format
you like (except a Julian date). For example, you may enter
10/6/90 or October 6, 1990. A value of "" defeats the status
of the expired date.
-f inactive The maximum number of days allowed between uses of a login ID
before that login ID is declared valid. Normal values are
positive integers. A value of -1 defeats the status.
login A string of printable characters that specifies the existing
login name of the user. It must exist and may not contain a
colon (:), or a newline (\n).
FILES
/etc/passwd, /etc/shadow, /etc/group
SEE ALSO
groupadd(1M), groupdel(1M), groupmod(1M), logins(1M), passwd(1),
passwd(1M), useradd(1M), userdel(1M), users(1).
DIAGNOSTICS
The usermod command exits with one of the following values:
0 The command was executed successfully.
2 The command syntax was invalid. A usage message for the usermod
command is displayed.
3 An invalid argument was provided to an option.
4 The uid given with the -u option is already in use.
6 The login to be modified does not exist or group does not exist.
8 The login to be modified is in use.
9 The new_logname is already in use.
10 Cannot update the /etc/group file. Other update requests will be
implemented.
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usermod(1M) UNIX System V(Essential Utilities) usermod(1M)
11 Insufficient space to move the home directory (-m option). Other
update requests will be implemented.
12 Unable to complete the move of the home directory to the new home
directory.
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