useradd(1M) SYSTEM ADMINISTRATION COMMANDS useradd(1M)
NAME
useradd - administer a new user login on the system
SYNOPSIS
useradd [-u uid [-o] [-g group] [-G group[,group...]] [-d dir] [-s shell]
[-c comment] [-m [-k skel_dir]] [-f inactive] [-e expire] login
useradd -D [-g group] [-b base_dir] [-f inactive] [-e expire]
DESCRIPTION
Invoking useradd without the -D option adds a new user entry
to the /etc/passwd and /etc/shadow files. It also creates
supplementary group memberships for the user (-G option) and
creates the home directory (-m option) for the user if
requested. The new login remains locked until the
passwd(1M) command is executed. Invoking useradd -D with no
additional options displays the default values for group,
base_dir, shel_dir, shell, inactive, and expire. The values
for group, base_dir, inactive, expire, and shell are used
for invocations without the -D option. Invoking useradd -D
with -g, -b, -f, or -e (or any combination of these) sets
the default values for the respective fields. [As
installed, the default group is other (group ID of 1) and
the default value of base_dir is /home]. Subsequent invoca-
tions of useradd without the -D option use these arguments.
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
The UID of the new user. This UID must be a non-
negative decimal integer below MAXUID as defined in
<param.h>. The UID defaults to the next available
(unique) number above the highest number currently
assigned. For example, if UIDs 100, 105, and 200 are
assigned, the next default UID number will be 201.
(UIDs from 0-99 are reserved.)
-o This option allows a UID to be duplicated (non-unique).
-g group
An existing group's integer ID or character-string
name. Without the -D option, it defines the new user's
primary group membership and defaults to the default
group. You can reset this default value by invoking
useradd -D -g group.
-G group
An existing group's integer ID or character-string
name. It defines the new user's supplementary group
membership. Duplicates between group with the -g and
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useradd(1M) SYSTEM ADMINISTRATION COMMANDS useradd(1M)
-G options are ignored. No more than NGROUPSMAX
groups may be specified.
-d dir
The home directory of the new 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.
-s shell
Full pathname of the program used as the user's shell
on login. It defaults to an empty field causing the
system to use /sbin/sh as the default. 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.
-m Create the new user's home directory if it doesn't
already exist. If the directory already exists, it
must have read, write, and execute permissions by
group, where group is the user's primary group.
-k skel_dir
A directory that contains skeleton information (such as
.profile) that can be copied into a new user's home
directory. This directory must exist. The system pro-
vides a ``skel'' directory (/etc/skel) that can be used
for this purpose.
-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 8, 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. Nor-
mal 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).
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useradd(1M) SYSTEM ADMINISTRATION COMMANDS useradd(1M)
login
A string of printable characters that specifies the new
login name of the user. It may not contain a colon (:)
or a newline (\n).
-b base_dir
The default base directory for the system. If -d dir
is not specified. base_dir is concatenated with the
user's login to define the home directory. If the -m
option is not used, basedir must exist.
FILES
/etc/passwd, /etc/shadow, /etc/group, /etc/skel
SEE ALSO
groupadd(1M), groupdel(1M), groupmod(1M), logins(1M),
passwd(1), passwd(1M), userdel(1M), usermod(1M), users(1).
DIAGNOSTICS
The useradd command exits with one of the following values:
0 The command was executed successfully.
2 The command line syntax was invalid. A usage message
for the useradd command is displayed.
3 An invalid argument was provided with an option.
4 The uid specified with the -u option is already in use.
6 The group specified with the -g option does not exist.
9 The specified login is not unique.
10 Cannot update /etc/group. The login was added to the
/etc/passwd file but not to the /etc/group file.
12 Unable to create the home directory (with the -m
option) or unable to complete the copy of skel_dir to
the home directory.
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