Add a Unix user account.
This command should be run by a user allowed to execute `sudo adduser` without being required to input a password. Somthing like the following entry in a sudoers file should work:- my_user ALL = NOPASSWD: /usr/sbin/adduser
username: Create a user with this user name.
--check: Do not actually make any changes, but report whether or not a change would be made.