Discussion:
"QXcbClipboard::setMimeData: Cannot set X11 selection owner"
(too old to reply)
René J.V. Bertin
2018-03-07 11:21:45 UTC
Permalink
Raw Message
Hi,

Apologies if I've asked this before: any idea what could cause this error message?

QXcbClipboard::setMimeData: Cannot set X11 selection owner

I'm seeing this sporadically in applications connected to an XQuartz X11 server that has been running for a certain time. It always seem to affect all the applications that are currently connected, but doesn't persist after an application restart (= I don't have to restart the server).

Hoping for some insight(s); I'm pretty certain that the issue is caused by something odd in XQuartz but cannot ignore the fact that it affects only Qt applications (GTk-based applications are not affected).

Thanks,
René
Thiago Macieira
2018-03-07 14:52:32 UTC
Permalink
Raw Message
Post by René J.V. Bertin
QXcbClipboard::setMimeData: Cannot set X11 selection owner
I'm seeing this sporadically in applications connected to an XQuartz X11
server that has been running for a certain time. It always seem to affect
all the applications that are currently connected, but doesn't persist
after an application restart (= I don't have to restart the server).
Hoping for some insight(s); I'm pretty certain that the issue is caused by
something odd in XQuartz but cannot ignore the fact that it affects only Qt
applications (GTk-based applications are not affected).
Obviously no GTK application is going to print something about
"QXcbClipboard". Can you see any other symptom besides the warning?
--
Thiago Macieira - thiago.macieira (AT) intel.com
Software Architect - Intel Open Source Technology Center
René J. V. Bertin
2018-03-07 15:36:43 UTC
Permalink
Raw Message
Post by Thiago Macieira
Obviously no GTK application is going to print something about
"QXcbClipboard".
Yeah, DOH :) I don't have the GTk sources on my system currently but it's likely
that somewhere there will be a call to xcb_set_selection_owner() in there too,
no? That's where the error message I see comes from: the call fails (doesn't
have the expected effect).
Post by Thiago Macieira
Can you see any other symptom besides the warning?
Sadly, yes. Copying to the clipboard no longer works in affected applications.
Instead I get that error message.

Fortunately this doesn't happen often, but that's also annoying for debugging.
I'm now dumping the immediately relevant variables when the error does occur,
and also use xcb_set_selection_owner_checked() and xcb_request_check() in hope
that will tell us what really goes wrong.

R.
Thiago Macieira
2018-03-07 18:53:23 UTC
Permalink
Raw Message
Post by René J. V. Bertin
Post by Thiago Macieira
Obviously no GTK application is going to print something about
"QXcbClipboard".
Yeah, DOH :) I don't have the GTk sources on my system currently but it's
likely that somewhere there will be a call to xcb_set_selection_owner() in
there too, no? That's where the error message I see comes from: the call
fails (doesn't have the expected effect).
Yes, it's likely. That doesn't mean GTK prints something as a result of that.
Post by René J. V. Bertin
Post by Thiago Macieira
Can you see any other symptom besides the warning?
Sadly, yes. Copying to the clipboard no longer works in affected
applications. Instead I get that error message.
And this symptom doesn't happen with GTK?
Post by René J. V. Bertin
Fortunately this doesn't happen often, but that's also annoying for
debugging. I'm now dumping the immediately relevant variables when the
error does occur, and also use xcb_set_selection_owner_checked() and
xcb_request_check() in hope that will tell us what really goes wrong.
--
Thiago Macieira - thiago.macieira (AT) intel.com
Software Architect - Intel Open Source Technology Center
René J. V. Bertin
2018-03-07 21:32:24 UTC
Permalink
Raw Message
Post by Thiago Macieira
Yes, it's likely. That doesn't mean GTK prints something as a result of that.
No, but I don't care about the error message in itself.
Post by Thiago Macieira
And this symptom doesn't happen with GTK?
And no, which is what I meant when I said that those applications aren't
affected (I use a minimal XCFE desktop, so always have a couple of GTk-based
applications running).

R.

Loading...