Display wlan0 IP address on screen on reMarkable

1-monitor_wlan0_ip.sh

#!/usr/bin/env bash
# /home/root/monitor_wlan0_ip.sh
iface=wlan0

get_dbus_iface() {
    dbus-send --system --dest=fi.w1.wpa_supplicant1 --print-reply=literal \
        /fi/w1/wpa_supplicant1 \
        fi.w1.wpa_supplicant1.GetInterface \
        "string:$iface" \
    | sed 's/^ *//g'
}

get_interface_state() {
    dbus-send --system --dest=fi.w1.wpa_supplicant1 --print-reply=literal \
        "$(get_dbus_iface)" \
        org.freedesktop.DBus.Properties.Get \
        string:fi.w1.wpa_supplicant1.Interface string:State \
    | awk '{print $2}'
}

monitor_interface() {
    dbus-monitor --system "type=signal,sender='fi.w1.wpa_supplicant1',interface='fi.w1.wpa_supplicant1.Interface',member=PropertiesChanged" --profile
}

get_ip() {
    ip addr show "$iface" | awk '/inet /{print $2}' | cut -d'/' -f1
}

print_ip() {
    fbink --flash -x 30 -y 310 "$(printf " %-15s " "$1")" 2> /dev/null
}

last_ip=

monitor_interface | while read line; do
    if [[ $(get_interface_state) = "completed" ]]; then
        cur_ip="$(get_ip)"

        if [[ -z $cur_ip ]]; then
            print_ip "ip pending..."

            while [[ -z $cur_ip ]]; do
                cur_ip="$(get_ip)"
                sleep 1s
            done
        fi
    else
        cur_ip="wlan offline"
    fi

    if [[ $cur_ip != "$last_ip" ]]; then
        last_ip="$cur_ip"
        print_ip "$cur_ip"
    fi
done

2-monitor-wlan0-ip.service

# /etc/systemd/system/monitor-wlan0-ip.service
[Unit]
Description=Monitor and print wlan0 IP
After=home.mount xochitl.service rm2fb.service

[Service]
Environment=PATH=/opt/sbin:/opt/bin:/opt/usr/bin:/sbin:/bin:/usr/bin
WorkingDirectory=/home/root
ExecStartPre=/bin/sleep 30
ExecStart=/home/root/monitor_wlan0_ip.sh
Restart=on-failure

[Install]
WantedBy=multi-user.target