#!/bin/sh
set -eu

MODE="${1:-}"

case "$MODE" in
    640x480|800x600|1024x768) ;;
    *)
        echo "Usage: $0 {640x480|800x600|1024x768}" >&2
        exit 1
        ;;
esac

: "${DISPLAY:=:0}"
export DISPLAY

exec xrandr -s "$MODE"