On Sat, 15 Jun 2019 19:41:13 +0200 Tobias Geerinckx-Rice <[email protected]> wrote:
> Jesse, > > Jesse Gibbons wrote: > > My Librem 13 laptop battery lasts much longer with a lower > > screen > > brightness. When it runs gnome on guix (and I haven't tried any > > other > > de) I have to turn down the brightness every time. This is not > > so with > > my other partition running PureOS. Is there a way to configure a > > default screen brightness in guix/gnome? > > Guix doesn't have a notion of ‘default’ screen brightness because > it doesn't know anything about brightness. > > My guess is that PureOS uses systemd; systemd provides a > backlight.service that reads the backlight brightness at shutdown, > stores it to disc, and writes that value back to the device at > next start-up. > > It would be a relatively trivial service to add, but that hasn't > been done yet :-) > > We do already provide a simple, script-friendly abstraction tool¹: > > $ guix install light > $ sudo light -S 50 # percentage > > It can even run setuid. > > Kind regards, > > T G-R > > [1]: As opposed to manually reading and writing `find /sys -path > *backlight*brightness*`. Thanks. I think I can add a service using the `light` tool. 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 if nobody beats me to it. -Jesse
