How to add System user that not be shown in lightdm login screen window or User Accounts? - Ask Ubuntu

i want create user no login, no home , not shown in lightdm login screen window or user accounts tool. others users in /etc/passwd: sshd, syslog, avahi...

i've tried command line:

useradd -r -u 1001 -m -g 1001 media 

but still can see user in user accounts tool:

thanks in advance!!

note: question has been claimed duplicated don't think so. main difference want create kind of user never shown in lightdm login screen window neither user accounts tool. user not have defined $home different thing.

use command:

$ sudo adduser --no-create-home --disabled-login --shell /bin/false --system --uid 1001 media $ sudo addgroup --gid 1001 media 

when running test, using man pages arguments, -gid in adduser command suppose create group specified name , supplied number. however, in functionality has apparently changed without docs being updated. on test, specifying --gid fails error: adduser: gid 1001 not exist. dropped --gid create new number when creating user, , added second command create group new user.

update:

edit file userid in /var/lib/accountsservices/users dir include these lines:

in case run this:

$ sudo nano /var/lib/accountsservices/users/media 

then ensure include these 2 lines:

(if user has logged on file should automatically created. if user hasn't logged on, won't exist. can manually create commandline above.)

 [user] systemaccount=true 

now either reboot or restart lightdm services (depending on ubuntu version):

(to avoid logging out can restart lightdm ctrl+alt+f2. run command below console.)

$ sudo service lightdm restart 

or (ubuntu 16.04 , higher)

$ sudo systemctl restart lightdm 

note:
default, userid below 500 automatically hidden.

some information in update can found in /etc/lightdm/users.conf file.