root@server:~# adduser viva -shell /bin/false -home /var/www
Warning: The home dir /var/www you specified already exists.
Adding user `webadmin' ...
Adding new group `webadmin' (1001) ...
Adding new user `webadmin' (1001) with group `webadmin' ...
The home directory `/var/www' already exists.  Not copying from `/etc/skel'.
adduser: Warning: The home directory `/var/www' does not belong to the user you are currently creating.
Enter new UNIX password:
Retype new UNIX password:
passwd: password updated successfully
Changing the user information for webadmin
Enter the new value, or press ENTER for the default
        Full Name []: ISI
        Room Number []: ISI
        Work Phone []: ISI
        Home Phone []:
        Other []:
Is the information correct? [Y/n] y
root@server:~#