I'm currently migrating to openbox without gnome session. In unity i can use the vendor keys to set the screen brightness, but in openbox I'm on my own. /sys/class/backlight/acpi_video0/brightness works fine, the problem is that I need sudo to set the brightness and that wouldn't work with keyboard mappings. xbacklight -get/set doesn't do or output anything. I don't really want to use xrandr --brightness. Are there any other options or a way to fix the problems with xbacklight or acpi_video0 ?