Hi Guys!

Did anybody came across a shell-way to alter the backlight intensity usally controlled with the F8 and F9 keys ?

I did take a look at the xmodmap and identified the XF86KbdBrightnessUp/Down event. But i don't have enough insight into xserver architecture to know where the event is handled. Does anybody have a hint ?

cheers,
Julian

You could "cheat" and use xdotool to fake a keypress.

edit: Wait a sec... are you trying to adjust screen brightness without x running? xdotool will certainly only apply if you're running x.

I'm sort of necrobumping here but I was trying to figure this out too and I've found that you can do it by writing a numeric value to /sys/class/backlight/pwm-backlight/brightness (keep in mind the max value set in the max_brightness file in the same folder).

I created two simple Bash scripts for raising and lowering the brightness via this file. I then bound the brightness keys to call those scripts when I press them (in dwm). The downside to this is that you have to change permissions on that brightness file to be writable by your normal user. Can anyone think of a safer option than that?

Edit: nevermind this solution, use mchack's solution below!

The file permissions don't survive a reboot. To make the changes permanent, add the following line to your /etc/rc.local:


*edit*: permissions should be 666, not 777 (no need to execute the file)

I wrote a trivial C program to handle brightness from the shell:

http://hack.org/mc/hacks/bright.c

It works without X as well.

Note, though, that you that it needs to be setuid root.