Re: How to set default screen brightness?

[Jesse Gibbons <jgibbons2357@gmail.com>]

On Sat, 15 Jun 2019 22:48:18 +0200
Tobias Geerinckx-Rice <me@tobias.gr> wrote:

> Jesse,
> 
> Jesse Gibbons wrote:
> > Thanks. I think I can add a service using the `light` tool.  
> 
> Yeah, I currently call it from my .xsession, which is horrible…
> A proper service would be most welcome.
> 
> > Administrators will likely prefer to install it on anything with 
> > a
> > display that runs on battery power, so I might contribute it in
> > gnu/services/pm.scm  
> 
> Ew.  We actually have that poorly-named file :-(
I agree the filename is cringeworthy. Unfortunatley it will be difficult
to change the file name now because it will break a lot of end-user OS
definitions and documentation.
> 
> > if nobody beats me to it.  
> 
> Go for it!
> 
> I still wonder whether it would be possible (and worth it) to do 
> this without external dependencies (i.e. basically reimplementing 
> ‘light’ in Scheme), so I won't be stepping directly on your toes 
> in the meantime.
It would be nice to script the commands in shepherd. All it needs to do
is read/write the value in the hardware either using syscalls or in a
virtual file it finds in /sys, and keep track of the value in a
designated location (something like /etc/light.d/backlight) when the
daemon is started/stopped, correct? The only potential problem I see is
it probably wouldn't work on a non-linux kernel like hurd or bsd; that
can be fixed when the need arises.
> Kind regards,
> 
> T G-R