[Interest] Run Qt Widget program with minimal Xorg installation on Linux

[René J.V. Bertin]

On Friday January 09 2015 22:12:22 ruslan wrote:
> In my case I installed VNC server just for control purposes. In
> standalone mode the Qt program should work on remote server without VNC,
> just with Xorg server.
> 
> I have same OS (Debian 7) om my works machine with same Xorg server and
> same Qt version. And there everything works well of course. So I can't
> understand what I miss on my VPS in comparisson with my works machine.
> Ok, I use there KDE as WM and on VPS it's Blackbox.

The WM is not the culprit: it's trying to do its job. If I understand correctly what you're saying your problem really lies with the use of VNC; either the server or the client don't support the sort of displaying technology your programme is trying to use.
Why not login to your VM over ssh, and try a remote X11 connection by setting the DISPLAY variable to the one you're using on your work machine? Launching the troublesome Qt application from a terminal like that might give you some more insight in what's happening - or if things work then you know that the VNC software is indeed the culprit.

Cheers,
R.