Permanently adjust screen brightness in Ubuntu / Linux Mint

This details a fix to reset the screen brightness in Ubuntu / Linux Mint during each boot.

This idea will work only if you have a file named brightness in the folder /sys/class/backlight/acpi_video0 and the hack is relevant for the Ubuntu (version < 12.04) where they had a bug in which the brightness is too high during each restart.

To know your systems current brightness level.

cat /sys/class/backlight/acpi_video0/brightness

Change brightness by changing the value

echo 0 > /sys/class/backlight/acpi_video0/brightness

To permanently set the brightness you can use the rc.loacal script file to change brightness which is executed at each reboot

sudo gedit /etc/rc.local

add the following line above “exit 0” seen at the bottom of the document

echo 0 > /sys/class/backlight/acpi_video0/brightness

restart your system after saving the file.