xbacklight -20 doesn't work

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1

Is it please possible to make it work in icewm ?

2

You first need to verify it will work on your system.

Start with the MAN pages as usual, note the " -get" option to list supported functions.
https://www.x.org/releases/X11R7.5/doc/man/man1/xbacklight.1.html

The ArchWiki is another good source for up to date info.
Note that it describes several issues which means xbacklight won’t work.
But also note that this ArchWiki article also describes many alternatives which might work on various systems.
https://wiki.archlinux.org/index.php/backlight#xbacklight

TSU

3

-get outputs nothing.

I can set brightness by

echo 0 > /sys/class/backlight/acpi_video1/brightnes

(the higher value the higher brightness is set)

4

Hi
Can you check the output from the following;


journalctl -b | grep backlight

Depending on the gpu in use, sometimes there are two competing backlight services, one needs to be disabled and masked…

5

Hi


journalctl -b | grep backlight
Jan 11 06:49:52 linux systemd[1]: Created slice system-systemd\x2dbacklight.slice.
Jan 11 06:49:52 linux systemd[1]: Starting Load/Save Screen Backlight Brightness of backlight:acpi_video1...
Jan 11 06:49:52 linux systemd[1]: Started Load/Save Screen Backlight Brightness of backlight:acpi_video1.
Jan 11 06:50:00 linux systemd[1]: Starting Load/Save Screen Backlight Brightness of backlight:acpi_video0...
Jan 11 06:50:00 linux systemd[1]: Started Load/Save Screen Backlight Brightness of backlight:acpi_video0.
6

Hi
See you have two running… does this system have dual gpus?

7

yes it does

8

You’re modifying your backlight but not using the xbacklight utilities.

Go to the ArchWiki link I provided and then search the page for

/sys/class/backlight

Believe you’ll have everything you need to understand what’s happening, adjust settings as desired, and configure a permanent/persistent setting.

TSU

9

xbacklight only works with Intel.

so it can’t work in my case

10

Xbacklight might not work for you,
But the ArchWiki describes how you can modify your backlight using other means.

TSU

11

Thank you. Command I’ve posted earlier https://forums.opensuse.org/showthread.php/548755-xbacklight-20-doesn-t-work?p=2996038#post2996038 is working fine and I’m satisfied with it. I don’t need to find another solution if it doesn’t have any hidden disadvantages/problems.