[Interest] "Dynamic session lookup supported but failed"

[Thiago Macieira]

On Friday 15 May 2015 20:57:31 René J.V. Bertin wrote:
> On Friday May 15 2015 10:19:00 Thiago Macieira wrote:
> > This means you used QtDBus, which tried to connect to the bus daemon,
> > which
> > was compiled with support for launchd but the .plist file wasn't loaded
> > into launchd.
> 
> I don't use it, not explicitly at least. Does Assistant use QtDBus, for
> instance?

Nothing in cross-platform Qt should be using it directly. The only thing that 
uses QtDBus directly is the XCB platform plugin (for the D-Bus menu and app 
indicators).

Put a breakpoint in dbus_bus_get and dbus_bus_get_private and see where they 
got called from.

> > But since Qt doesn't ship with the daemon, the D-Bus libraries or the
> > .plist file, the problem here is that your system *does* have them but
> > didn't configure
>
> This isn't (entirely) true. I indeed have DBus installed, and also running
> on my "console" session, so that for instance KMail (which I'm typing in
> right now) works.

How did you start the daemon for that session?

> > them. Why do you have the D-Bus library somewhere that QtDBus could find
> > it but didn't configure it properly?
> 
> The exact same way a similar situation can arise on Linux: logging in
> remotely over SSH without starting a dedicated session DBus and starting an
> application to display remotely using the xcb plugin. On Linux you'll also
> get an error when you don't have a launched that session DBus, but only
> when the application actually tries to connect to it. You don't get that
> error with Assistant for instance.

Correct, it will complain that it can't autostart because you've got no X 
connection. If you did (ssh -X), then it would autostart without complaining.

This is expected behaviour.

-- 
Thiago Macieira - thiago.macieira (AT) intel.com
  Software Architect - Intel Open Source Technology Center