[Bug 321176] Re: [Jaunty] alarm-clock causes screen to freeze

[Gustavo Carneiro]

Here's how I think you can reproduce the problem.  Just write a program
(C or Python, doesn't matter) that:

 1. Creates a toplevel window (make it a fullscreen window for increased effect)
 2. calls gdk_pointer_grab on that window
 3. never calls gdk_pointer_ungrab

>From that moment on, the program captures the pointer (and as side
effect also the keyboard).  Consequently, the clueless user thinks that
"X is frozen", when in actual fact is just "poorly written app grabs the
pointer and never ungrabs it".

This is *NOT* a PyGTK bug.  This is *NOT* a Gtk+ bug.  This is *NOT* a
Xorg bug.

Every programmer that ever needed to write code to grab the mouse
pointer will occasionally temporarily write code that grabs the pointer
but forgets to ungrab it.  I have been there myself.  But the X session
is not completely frozen.  You can recover by pressing <Ctrl><Alt>F1,
login in a linux console, and manually kill the offending program.  Then
you can go back to the X11 console (normally <Alt>F7), and everything is
back to normal.

And by the way, I am tired of receiving these messages about a non-pygtk
bug just because I am watching pygtk bugs in general.  If someone knows
of a way for me to opt out, please let me know.  Thanks!

-- 
[Jaunty] alarm-clock causes screen to freeze
https://bugs.launchpad.net/bugs/321176
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