useradd [-c comment] [-d home_dir]
[-e expire_date] [-f inactive_time]
[-g initial_group] [-G group[,...]]
[-m [-k skeleton_dir]] [-p passwd] [-r]
[-s shell] [-u uid [ -o]] login
useradd -D [-g default_group] [-b default_home]
[-f default_inactive] [-e default_expire_date]
[-s default_shell] |
When invoked without the -D option, the useradd command creates a new user account using the values specified on the command line and the default values from the system. The new user account will be entered into the system files as needed, the home directory will be created, and initial files copied, depending on the command line options.
When invoked with the -D option, useradd will either display the current default values, or update the default values from the command line. If no options are specified, useradd displays the current default values.
The new user's password file comment field.
The new user will be created using home_dir as the value for the user's login directory. The default is to append the login name to default_home and use that as the login directory name.
The date on which the user account will be disabled. The date is specified in the YYYY-MM-DD.
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.
The group name or number of the user's initial login group. The group name must exist. A group number must refer to an already existing group. The default group number is 1.
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. The default is for the user to belong only to the initial group.
The user's home directory will be created if it does not exist. The files contained in skeleton_dir will be copied to the home directory if the -k option is used, otherwise the files contained in /etc/skel will be used instead. Any directories contained in skeleton_dir or /etc/skel will be created in the user's home directory as well. The -k option is only valid in conjunction with the -m option. The default is to not create the directory and to not copy any files.
The encrypted password, as returned by crypt(3). The default is to disable the account.
This flag is used to create a system account. That is, a user with a UID in the range reserved for system account users. If there is not a UID free in the reserved range the command will fail.
The name of the user's login shell. The default is to leave this field blank, which causes the system to select the default login shell.
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. The default is the smallest ID value greater than 499 which is not yet used.
The initial path prefix for a new user's home directory. The user's name will be affixed to the end of default_home to create the new directory name if the -d option is not used when creating a new account.
The date on which the user account is disabled.
The number of days after a password has expired before the account will be disabled.
The group name or ID for a new user's initial group. The named group must exist, and a numerical group ID must have an existing entry.
The name of the new user's login shell. The named program will be used for all future new user accounts.
The new user's password file comment field.