I had another folder named acpi_video0
in this location /sys/class/backlight/
I added following command at the end but before exit 0
in gksu gedit /etc/rc.local
file:
echo 0 > /sys/class/backlight/intel_backlight/brightness
echo 0 > /sys/class/backlight/acpi_video0/brightness
It worked for me. And now I want to get current brightness and save it into a file to restore it at next restart.
How to functionality last adjusted brightness load after next reboot?
Step 1: Check brightness levels
Set your brightness to maximum and check current level by below command:
cat /sys/class/backlight/acpi_video0/max_brightness
(my laptop max brightness is 100 :)
Now set your brightness to minimum and check current level by evoking next command:
cat /sys/class/backlight/acpi_video0/brightness
(my laptop min brightness level is 0 :)
Step 2: Create a file to store your current brightness:
sudo touch /etc/init.d/prev_brightness
sudo chmod o+w /etc/init.d/prev_brightness
Step 3: Create a script that stores your current brightness(the save_screen_brightness
file) when shutting down into the file prev_brightness
that you created in the previous step:
sudo touch /etc/init.d/save_current_brightness
sudo chmod +x /etc/init.d/save_screen_brightness
Open the save_screen_brightness
file with your favorite editor app:
gksu gedit /etc/init.d/save_screen_brightness
And put this script into it:
#!/bin/sh
cat /sys/class/backlight/acpi_video0/brightness > /etc/init.d/prev_brightness
Save it and go to next step ;)
Step 4: Make the script run every time we shutdown or reboot the computer:
sudo ln -s /etc/init.d/save_current_brightness /etc/rc0.d/K99save_screen_brightness
## Shuttingdown ^^
sudo ln -s /etc/init.d/save_current_brightness /etc/rc6.d/K99save_screen_brightness
## Rebooting ^^
Step 5: Load the value we stored when starting the computer:
Add the following line at the end and before exit 0
into your /etc/rc.local
file:
cat /etc/init.d/prev_brightness > /sys/class/backlight/acpi_video0/brightness
That's it ;)
Thanks to @Hevilath's answer and @user207402's answer and also @AiPdimi's answer