On Sun, Sep 19, 2021 at 4:05 AM Ed Greshko <ed.gres...@greshko.com> wrote:
> Not a everyday systemd service writer.... > > I've written a user service file to start an app on login. It works well > for Xorg with Environment=DISPLAY=:0. > > But I've found that under Wayland the DISPLAY=:1 after a logout of Xorg > and login to a > Wayland session. > > What would be the proper way to get the DISPLAY environment varible use it > as opposed > to "hard" coding it? > The proper way is to have *the desktop environment* upload DISPLAY (and whatever else is relevant, such as XAUTHORITY or WAYLAND_DISPLAY or XDG_SESSION_TYPE) into systemd --user, so that it would be automatically available to your service *without *doing anything special. For example, gnome-session does this for GNOME (it calls systemd's UnsetAndSetEnvironment in gsm-util.c), and /etc/X11/xinit/xinitrc.d/50-systemd-user.sh handles the bare minimum for other Xorg-based desktops (when startx is used). If KDE integrates with systemd --user in any way (i.e. if it actually has a "plasma-core.target" that you mention), I'd really expect it to do the same before it tries to start its own targets, otherwise they would be kind of useless. -- Mantas Mikulėnas