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Hi.all
I will ask you a question again.An application created with Qt WidgetApplication can be executed with user privileges, but an error will occur if executed as root.
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qt.qpa.screen: QXcbConnection: Could not connect to display: 0
Could not connect to any X displayThis state becomes a problem when starting an application from rc.local.
Is there a solution?
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Hi @taku-s,
Does your program needs to be run as root? (which would be a very bad idea).
Otherwise start it with
su -c yourprog <user>
.Regards
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@taku-s
I may not know what I am talking about here. So take with a pinch of salt. But (a) I thought there are sometimes problems with running X Windows programs as root instead of logged in user, and (b) if you start an app fromrc.local
what is it doing looking for an X display anything, you cannot access/assume any X connection anything from there, it's not supposed to be for programs requiring UI interaction?
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Thank you, everyone.
As you said, it may not be a Qt issue.
The Debian 10 I use seems to have changed from Xorg to Wayland, so this is the problem?
I will try the startup method from the user.