On Friday May 15 2015 13:30:54 Thiago Macieira wrote: > > But that is the platform plugin used on Linux, and yet it doesn't complain > > when I start, say, Assistant without a session DBus? > > By "without a session", do you mean in SSH without -X? Why would you want to > run a graphical application without a graphical server?
I said "without a session DBUS". That's not the same thing. That just means that no dbus daemon was started to serve the current session. And again, you can SSH in without -X and then set DISPLAY to the direct address of your screen, just like one did in the telnet days. As long as DISPLAY is set to a valid X server, graphical applications will run. > libqxcb.dylib`DBusConnection::DBusConnection(this=0x0000000104b0d330, > parent=<unavailable>) + 131 at dbusconnection.cpp:61 > > You're using XCB. It expects X behaviour. Yes, I am. But X and DBus are 2 separate things. If it were "X behaviour" to have a session DBus when starting an application, I should see the error under Linux too when there is no session DBus. > > What is "it" here? > > I was wrong. It would have complained if you had no X. > > The problem here is that you *do* have X, so it didn't complain because it > found the session bus. Again, what is "it"? And once more, there is no session bus to be found in the context I'm talking about ... > No, X11 autostart is a feature I introduced some time in 2006 in D-Bus. > Probably version 0.62 or 0.90. In the Qt interface to DBus I presume? The dbus-daemon process that provides the actual DBus cannot start itself after all... What I don't understand then is why KDE4 and KF5 applications (from Ubuntu 14.04) complain about a missing dbus when I launch them over ssh, and tell me to do `eval dbus-launch` by hand. > OS X autostart was introduced a year or two later, by one of the early KDE-on- > Mac maintainers. > > > Either way, DBus on OS X doesn't look at X connections, to my knowledge. > > Correct. > > The mismatch here is that your D-Bus is looking at the Aqua connection, while > your Qt is looking at the X connection. You're seeing the problem because X > is > working but Aqua isn't, under your SSH connection. Hmmm, so what you're saying is that QtDBus tries to create a DBus session, and then prints an error message that suggests it only tried to find an existing session? And that I don't get the error when I launch the same application under SSH on a Linux box because a DBus session is created silently and successfully (and aborted when I stop the application)? > > Other people haven't noticed this problem because they either get both > successful or both failing. Actually, I think very few people have tried to use the xcb plugin on OS X, and Qt4 hasn't built for X11 on OS X since quite a few (minor) versions (MacPorts says 4.4.3 but I think Fink has a somewhat later version). > If the display connection isn't working, then you > won't see the D-Bus error anyway. With Aqua, with X it's another matter. The (remote) terminal is independent from the display connection. Which makes me realise: when I mention ssh connections/sessions, I mean that I type `slogin [-X] host` or `ssh -Xf host command` in a terminal. Not something involving a remote graphical login screen taking over my whole local X server ... R. _______________________________________________ Interest mailing list [email protected] http://lists.qt-project.org/mailman/listinfo/interest
