Toggles external monitors on/off.

multihead

#!/bin/bash
# multihead.sh - Toggles external monitors on/off.
#
# Copyright (C) 2021 Daniel Rudolf (<https://www.daniel-rudolf.de>)
# License: The MIT License <http://opensource.org/licenses/MIT>
#
# SPDX-License-Identifier: MIT

APP_NAME="$(basename "${BASH_SOURCE[0]}")"

ACTION="toggle"
while [ $# -gt 0 ]; do
    case "$1" in
        "--on")
            ACTION="on"
            ;;

        "--off")
            ACTION="off"
            ;;

        "--toggle")
            ACTION="toggle"
            ;;

        "--help")
            echo "Usage:"
            echo "    $APP_NAME [--toggle|--on|--off]"
            exit 0
            ;;

        *)
            echo "$APP_NAME: Invalid option: $1" >&2
            exit 1
            ;;
    esac
    shift
done

CARD="card1"
INTERNAL="eDP-1"
EXTERNALS=()
EXTERNALS_ACTIVE=()

for DIR in /sys/class/drm/"$CARD"-*; do
    SOURCE="$(basename "$DIR")"
    SOURCE="${SOURCE:${#CARD}+1}"

    if [ "$SOURCE" == "$INTERNAL" ]; then
        continue
    fi

    EXTERNALS+=( "$SOURCE" )
    if [ "$(cat "$DIR/status")" == "connected" ]; then
        EXTERNALS_ACTIVE+=( "$SOURCE" )
    fi
done

if [ "$ACTION" == "toggle" ]; then
    if [ ${#EXTERNALS_ACTIVE[@]} -gt 0 ]; then
        ACTION="off"
    else
        ACTION="on"
    fi
fi

if [ "$ACTION" == "off" ]; then
    for SOURCE in "${EXTERNALS_ACTIVE[@]}"; do
        echo "Turning off $SOURCE..."
        echo off > "/sys/class/drm/$CARD-$SOURCE/status"
    done
else
    for SOURCE in "${EXTERNALS[@]}"; do
        echo -n "Probing $SOURCE... "
        echo detect > "/sys/class/drm/$CARD-$SOURCE/status"
        cat "/sys/class/drm/$CARD-$SOURCE/status"
    done
fi

multihead-128x128.png

multihead-32x32.png

multihead-48x48.png

multihead-64x64.png

multihead-96x96.png

multihead.desktop

[Desktop Entry]
Version=1.0
Terminal=false
Icon=multihead
Type=Application
Categories=System;Settings;HardwareSettings;
Exec=sudo multihead
Name=Toggle External Monitors
Name[de]=Externe Bildschirme umschalten
Comment=Toggle external monitors on/off
Comment[de]=Schalte externe Bildschirme an/aus
Keywords=Panel;Projector;xrandr;Screen;