[Tigervnc-devel] Lost keyboard events after starting DBUS

[Adam Tkac]

On Tue, Apr 21, 2009 at 12:05:30PM +0200, Peter Åstrand wrote:
>> After executing:
>>
>> eval `dbus-launch --sh-syntax --exit-with-session`
>>
>> in a xterm window, then keyboard events are occasionally lost. If you 
>> type, say, 1234567890, you will actually end up with something like 
>> 12356890. It's
>
> The problem is actually not limited to Xvnc, I've been able to reproduce  
> it on a wide range of Xservers and platforms:
>
> TigerVNC, X.Org 1.5.3: fails
> xorg-x11-server-Xvfb-1.6.1-6.fc11.x86_64: fails
> xorg-x11-server-Xvfb-1.5.3-15.fc10.i386: fails
> xorg-x11-server-Xvfb-1.5.2-6.fc9.x86_64: fails (many events lost)
> xorg-x11-server-Xorg-1.6.0-16.fc11.x86_64: fails
> xorg-x11-server-Xorg-1.5.2-6.fc9.x86_64: fails
> xorg-x11-server-Xorg-1.3.0.0-47.fc8: fails
>
> In the Xvfb case, I was simulating keypresses using XSendEvent. If you  
> want to try this yourself, it's quite simple:
>
> 1. Login on the console, or unset XAUTHORITY.
>
> 2. xinit -- :47
>
> 3. eval `dbus-launch --sh-syntax --exit-with-session`
>
> 4. Start typing,
>
> It seems like the rate of lost keys is basically one per second: By 
> typing one character per second, the problem is most easily triggered.
>
> Using Wireshark, I've seen that all KeyPress events are actually 
> delivered to the application. It happens with both xterm and 
> gnome-terminal, both with bash and csh. I guess what's left is either:
>
> 1) A bug that's present in both xterm and gnome-terminal (seems unlikely)
>
> or
>
> 2) Some kind of bug in libX11

Good catch. Could you report bug to X bugzilla, please? I guess that
core input processing in server itself is broken.

Regards, Adam

-- 
Adam Tkac, Red Hat, Inc.