Comment 154 for bug 1197395

Is there an upstream bug report ? If not, I suggest this could be a better place to discuss this issue. Or perhaps not.

I think, as many others in this thread, that the solution we came to is a half solution only. Not setting XDG_RUNTIME_DIR at all when using 'su -l' breaks many things, and not just graphical applications. I'm one of those people that things running graphical applications using su is a bad idea.

There is a reason behind the distinction between 'su' and 'su --login'. The latter is supposed to recreate a complete login environment. I think it then should also register a session within logind and of course provide a XDG_RUNTIME_DIR.

I came across this issue trying to use 'systemctl --user' over 'su' to activate a (pulseaudio) systemd unit for a ad-hoc user. This command appears in a deployment shell script and I had to set XDG_RUNTIME_DIR manually in a non portable way. I do not like it.

This is to say that the problem is not just with graphical application, but to anything that happens to use XDG_RUNTIME_DIR. And it seems that more and more console applications should use this.

Perhaps using 'su' for that is wrong and we should have another command that runs the exact same pam modules than login.