[mythtv-users] mythfrontend over vnc crashes

[Douglas Paul]

Hello,

On Mon, Mar 01, 2021 at 07:57:25AM -0600, Leo Butler via mythtv-users wrote:
> I upgraded my frontend and separate backend from ubuntu 18.04 to 20.04,
> then upgraded myth from the .29 mythbuntu ppa to .31 (all due to the
> pending changes involving the metadata grabbers).
> 
> The frontend and backend both work fine after the upgrade.
> 
> Before the upgrade, I was able to use vnc tunnelled over ssh to run
> mythfrontend on the backend, too (I do most editing this way). Here is
> the complete command to run the server:
> 
> [...]
> 
> The vncserver runs a fluxbox window manager.
> 
> After the upgrade, that no longer works even though mythfrontend works
> on the backend (under the gnome desktop). It looks like a Qt-related
> problem, but I am at a loss how to fix it.
> 
> Attached are stdout and stderr from
> 
> mythfrontend > m.log 2> m.err.txt
> 
> in a terminal inside the fluxbox-managed vnc session.

> [...]
> The X11 connection broke (error 4). Did the X11 server die?

If it is of any use, I run the frontend routinely from a VNC desktop
running Openbox. In my case, I am running TigerVNC not TightVNC. This is
running in a VM (with no GPU access) on a server, also with no GPU.

The frontend seems to run completely fine with software OpenGL.

I am also running 0.32-pre, which hasn't been updated in a bit, so I
don't know if something has been committed to both 0.31-fixes and
0.32-pre that could cause this problem, since I built, but I hope not. I
would have no way to get hardware OpenGL on this machine...

The error from X11 is EINTR, which means that the process should have
received some signal when communicating to the X server. You could see
which if you ran the frontend from a debugger.

However, because of the error here, you might be able to see something
else in the logs for VNC (usually in ~/.vnc/$DISPLAY.log). They might
point to the origin of the problem. Maybe there is some bug in that
particular VNC server.

-- 
Douglas Paul