Re: adding environment variables to /etc/config.scm

["Ludovic Courtès" <ludo@gnu.org>]

Hello Jonathan,

"Jonathan Lane" <jon@dorsal.tk> skribis:

> I have a laptop with Intel graphics and I need to set the environment
> variable "COGL_ATLAS_DEFAULT_BLIT_MODE=framebuffer" to fix GPU 
> corruption issues as described here:
>
> https://wiki.archlinux.org/index.php/Intel_graphics#Troubleshooting
> https://bugs.freedesktop.org/show_bug.cgi?id=88584
>
> Unfortunately, it's supposed to go in /etc/environment, and that file
> gets clobbered every time I reboot or run `guix system reconfigure`.

Indeed, on Guix System one is not supposed to modify config files in
place.

Instead, you declare every aspect of your system config in your
‘operating-system’ declaration, and then run ‘reconfigure’ so that it’s
in effect.

To add environment variables to /etc/environment, you would “extend”
‘session-environment-service-type’, like so:

  (simple-service 'cogl-variable session-environment-service-type
                  '(("COGL_ATLAS_DEFAULT_BLIT_MODE" . "framebuffer")))

The expression above provides a service that you can add to the list in
the ‘services’ field of your ‘operating-system’ declaration.

HTH!

Ludo’.