From kde-bugs-dist  Sat Jun 26 20:24:10 1999
From: Ken Harris <harris () axon ! rutgers ! edu>
Date: Sat, 26 Jun 1999 20:24:10 +0000
To: kde-bugs-dist
Subject: Bug#1475: Mod2Mask bit of XButtonEvent->state gets stuck on.
X-MARC-Message: https://marc.info/?l=kde-bugs-dist&m=93050912702573

Package: KWM
Version: KDE 1.1.1
Severity: Medium

Hi,

I'm reporting a bug I have found running certain X applications under
KDE 1.1.1 on Red Hat Linux.  My guess is that the problem is down to the
window manager KWM.

An example program that exhibits this problem is XGobi, whose source
code is freely downloadable from
http://www.research.att.com/areas/stat/xgobi.

The problem is this:  Sometimes the application runs fine.  But
sometimes, certain buttons stop responding to mouse clicks.  To
reproduce this using XGobi, go to the "Grand Tour" screen (by pressing
'g') and try clicking the
"varaible selector" buttons to the right of the screen.  This sometimes
works.  However, after a certain amount of time running KDE, the buttons
no longer respond.  The only way to get them to respond again is to log
out and start another KDE session.

Using a debugger I managed to trace the problem.  The problem is that
when the event handler routine for the button is called, the Mod2Mask
bit of the state field of the XButtonEvent structure passed to the
routine is set on - so the state field has the value 16.  The program is
looking for mouse clicks with no shift or control, so it tests for
state==0 - and misses the clicks.

I am not sure what causes this bit to get stuck on - in fact I'm not
sure what Mod 2 represents.  But whatever causes it, I can't get it to
go away without restarting KDE.

Best regards,

Ken Harris.