As a followup, using the function keys for brightness (in my case: fn+Alt+F5 or F6) seems to be remembered. So, at least for me, there is a workaround.
ON the same computer, xbacklight was working well with Knoppix 7.4 and 7.6.
It is not working for Knoppix 7.7.1. The command:
returns:Code:xbacklight -get
Code:No outputs have backlight property
As a followup, using the function keys for brightness (in my case: fn+Alt+F5 or F6) seems to be remembered. So, at least for me, there is a workaround.
The "No outputs have backlight property" error is apparently because xbacklight does not choose the right directory in /sys/class/backlight. Running:
shows that directory is named intel_backlight.Code:ls /sys/class/backlight
We should then be able to specify the directory by setting the Backlight option of the device in xorg.conf, configuring the section "Device" as follows:
Code:/etc/X11/xorg.conf Section "Device" Identifier "Card0" Driver "intel" Option "Backlight" "intel_backlight" EndSection
Last edited by philo; 11-03-2016 at 08:20 PM.
Actually only these 2 lines need to be inserted:
Should also have mentioned the link for the solution to that issue:Code:Driver "intel" Option "Backlight" "intel_backlight"
https://wiki.archlinux.org/index.php...ght#xbacklight
Last edited by philo; 11-13-2016 at 03:09 PM.

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