Debian doesn't create /var/run/utmp anymore.
The command "who" can't work longer.
USERS=`who -q | tail -n 1 | sed 's/[a-z #]*=//'`
Replacement of the line above with the line below does the job for me.
USERS=`loginctl list-users | tail -n 1 | cut -c 1`
Greetings, Andreas
