Make it possible to inject environment variables into openrc from outside.

[amano-kenji]

Some OpenRC user services need access to WAYLAND_DISPLAY, DISPLAY, and SWAYSOCK environment variables.

Because sway is started outside openrc, openrc doesn't have these environment variables.

dinit let me inject environment variables from within sway. Thus, sway can inject environment variables into dinit and then start graphical runlevel of dinit.

[navi-desu]

you can already do that with rc_env_allow in rc.conf, then it'll be picked up from the environment that called openrc or rc-service.

#782 will improve on that, with rc-update env ... to control the envdir. until then, rc_env_allow is what i use for WAYLAND_DISPLAY and such

[amano-kenji]

If sway executes openrc --user graphical, graphical runlevel receives environment variables specified in rc_env_allow?

[navi-desu]

yea