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Screen Brightness

I had no luck with a screen brightness step of 1, in acpi handler. Adding these clauses to works better.

       actual_bl=`cat $bl_dev/actual_brightness`
       # Lower brightness has no effect until it is lowered enough to change actual_brightness.
       # Brightness less than 10 causes problems when increasing!
       while [ $actual_bl -gt 10 -a $actual_bl == `cat $bl_dev/actual_brightness` ]
           echo $((`cat $bl_dev/brightness` - 1)) > $bl_dev/brightness
       actual_bl=`cat $bl_dev/actual_brightness`
       # Change in brightness has no effect until it is changed enough to change actual_brightness.
       while [ $actual_bl -lt 100 -a $actual_bl == `cat $bl_dev/actual_brightness` ]
           echo $((`cat $bl_dev/brightness` + 1)) > $bl_dev/brightness

Dave Cohen (talk) 12:34, 4 July 2013 (UTC)

This is a mess, it should be cleaned up before adding it to the article (e.g use $( ) instead of `, input redirection not cat, avoid [, etc). -- Alad (talk) 14:34, 4 June 2015 (UTC)

Hi! I think it can be useful if we put a banner on top of this page to warn users that logind already implements some acpid features. Eventually we can highlight which of these features are already implemented, and a link to the systemd wiki page. Nierro (talk) 17:40, 3 August 2013 (UTC)

The Power Management page (a section from systemd was recently moved there) links to this page correctly, but you are right - some note to read Power Management#Power management with systemd first would be useful. But I'd still keep the old examples using pm-suspend etc. until pm-utils is finally deprecated. -- Lahwaacz (talk) 17:51, 3 August 2013 (UTC)
The fact is that pm-utils, being no more a dep of upower, is really unlikely to be installed. While every user should have systemd and "systemctl suspend". So I find it better to use systemctl instead of pm. For the banner, i think it should be added. Nierro (talk) 18:29, 3 August 2013 (UTC)
It seems i'm jumping forward when upower 0.9.21 hit extra...i'm using testing so i didn't notice. By the way systemctl suspend is equivalent to pm-suspend, and i guess upower 0.9.21 will hit extra in a few days. Nierro (talk) 18:31, 3 August 2013 (UTC)
Alright, but this doesn't make much sense - why not use the logind mechanism you talked about? I'd delete that example too, there's already one example on button/lid close. -- Lahwaacz (talk) 18:51, 3 August 2013 (UTC)
Damn sorry, you're right obviously. I must be really tired. Thank you for pointing that out! Nierro (talk) 18:54, 3 August 2013 (UTC)
Is there more to discuss here? Other things I could think of is check if systemd-logind is running like Debian does [1], or perhaps mention systemd-inhibit. But I doubt either is worth documenting. -- Alad (talk) 14:30, 4 June 2015 (UTC)
Closing, added a note with [2]. Further discussion in #Force_suspend_when_lid_is_closed -- Alad (talk) 08:34, 7 February 2022 (UTC)

Minor addition to Introduction

I'm troubleshooting a laptop specific acpi module. The command `dmesg | grep [module]` reports the module is loaded. Subsequently, I assumed the ACPID package was also installed and loaded. I think a little bit of explanation here would go a long way to warn about this gap.

[add info: Why a module could be loaded, but not the ACPID package/Why the package might be inactive]
[maybe a test, then continue with the existing intro]
Install the acpid package.
Start and/or enable acpid.service.
# systemctl start acpid.service
Verify the service is loaded:
# systemctl status acpid.service

Xtian (talk) 17:31, 29 October 2017 (UTC)

The ACPI modules come with the kernel (i.e. the linux package), not with the acpid package. So why the acpid package might be missing: simply because you haven't installed it yet. I'm sorry but that's a basic thing to know about your system, I don't see why it should be included on this page when it's not anywhere else on the wiki. Also note that the acpid package is not necessary to make the ACPI module(s) more functional - it is just one way to connect events to actions, there are multiple alternatives. -- Lahwaacz (talk) 20:09, 29 October 2017 (UTC)
I don't follow this logic. The wiki is very informative, and instructs users in many basic things to know about their systems. If your objection is about style--for example--Why add more explanation, when a simple one liner will do? I get that objection. I figured out that I skipped over this line, and I fixed it. But for my taste, I like those wiki pages which instruct readers to test first and then choose an action. But if your objection is writing more instruction gives the appearance this is the only way, then more explanation is needed, not less. I'm not the person to write that. I simply like the explicit test style I find in many of these wiki pages better than a more terse style. Xtian (talk) 01:31, 30 October 2017 (UTC)
I think the information you want is already listed in ACPI modules which is link in first sentence. Maybe you miss that link. --Fengchao (talk) 04:39, 30 October 2017 (UTC)

Volume control with Enlightenment


I just installed acpid and when I read about the volume control in "Tips and Tricks", I figured I could instead configure the key bindings in Enlightenment to trigger the volume control events... and it sure worked just fine.

I am wondering if it would be worth it to mention here, that in Enlightenment (and possibly other desktop window managers) the volumen events can be configured in the key bindings once acpid is installed.

Personally, I prefer it that way, since I configure a whole bunch of key bindings in Enlightenment anyway, and prefer to do as much as possible in one place.

—This unsigned comment is by Drtebi (talk) 02:39, 25 March 2018‎. Please sign your posts with ~~~~!

If you bound XF86AudioRaiseVolume etc. in your desktop environment, then you most likely don't need acpid at all. Note that the Extra keyboard keys page is linked at the top of the acpid page. -- Lahwaacz (talk) 08:45, 25 March 2018 (UTC)

Connect keys to ACPI Events with .*

"event=video/brightnessdown" didn't work for me until I appended ".*" like in the alternative configuration example. Maybe one could add this to the page? Nesuma (talk) 16:24, 1 October 2018 (UTC)