I'm trying to setup my Xmonad to change the back-light intensity on my laptop.
However, to do so, I have to be able to write to the file /sys/class/backlight/intel_backlight/brightness, which requires the application performing the update to be sudoed (all other suggestions I have tried to use to change the back-light intensity seems to "simulate" it by reducing the brightness of the pixels rather than the back-light).
I've written the necessary code to perform this update and tested it using a sudoed ghci instance, however, when I add this to my Xmonad config, I get a permission denied error.
My question is, what are the usual methodologies for giving window managers extra permissions where required? (I'd ideally not want to change the permissions of this file)
I have this in in my sudoers configuration:
# /etc/sudoers.d/brightness-modALL ALL = (ALL) NOPASSWD: /usr/bin/tee /sys/class/backlight/intel_backlight/brightness
This allows you to execute, from user mode, commands like
echo 200 | sudo tee /sys/class/backlight/intel_backlight/brightness
Always use visudo to edit sudoers configuration stuff.