Duet IDisplay alternative for linux using X11vnc, for android best client is AndroidVNC

second-display.sh

#!/bin/bash
x=1920        # X size of second display 
y=1080        # Y size of second display
X_DISPLAY=eDP1  # Your screen, found it whith xrandr
POSITION=left #right


add_modeline() {
        local modeline name
        modeline="$(gtf "$2" "$3" "$4" | sed -n 's/.*Modeline "\([^" ]\+\)" \(.*\)/\1 \2/p')"
        name="$(echo "${modeline}" | sed 's/\([^ ]\+\) .*/\1/')"
        if [ -z "${modeline}" -o -z "${name}" ] ; then
                echo "Error! modeline='${modeline}' name='${name}'"
                exit 1
        fi
        xrandr --delmode "$1" "${name}"
        xrandr --rmmode "${name}"
        xrandr --newmode ${modeline}
        xrandr --addmode "$1" "${name}"
}

if [ $1 == stop ]
        then
                xrandr --output VIRTUAL1 --off
                killall x11vnc
                sudo iptables -D INPUT -p tcp --dport 5900 -j ACCEPT
fi
if [ $1 == start ]
        then
                add_modeline VIRTUAL1 $x $y 60
                sleep 5
                add_modeline VIRTUAL1 1920 1080 60
                sleep 5
                xrandr --output VIRTUAL1 --mode ${x}x${y}_60.00 --${POSITION}-of eDP1
                sleep 5
                x11vnc -clip ${x}x${y}+0+0 -forever  &> /dev/null &
#               x11vnc -clip xinerama1 -forever > /dev/null &
                sudo iptables -I INPUT 1 -p tcp --dport 5900 -j ACCEPT
                ip a | grep inet | cut -d " " -f 6  | grep '192.\|10.'
fi