Re: [dev] [dwm] Focus bug in 5.6 when using unclutter

On Mon, Aug 03, 2009 at 09:56:40AM +0100, Anselm R Garbe wrote:
> Hi Eivind,
>
> thanks for your investigation. I looked through the code and
> remembered that unfocus() sets the input focus to the root window in
> order that clients are notified with FocusOut (in terminals this has
> the effect that the cursor turns into unfocused state).
>
> So in general there is nothing wrong with setting the input focus to
> the root window during unfocus() -- that's also usual practice in
> other WM implementations. I suspect there is a side-effect with
> unclutter though, haven't looked at its code, but it surely must do
> some nasty trick to void the cursor, which might have some side-effect
> if it receives FocusIn on the root window, which is why I propose to
> look at unclutter next, since I bet the real fix is on that side... ;)
>
> But let's see.
>
> Kind regards,
> Anselm
>
>
> 2009/8/3 Eivind Uggedal <eivind_AT_uggedal.com>:
> > After updating from 5.5 to 5.6 I encountered a bug relating to unclutter[1].
> > Steps to reproduse:
> >
> > 1. Start dwm 5.6 with default config and unclutter with default params.
> > 2. Open more than one window in the active tag.
> > 3. Wait until unclutter hides the cursor.
> > 4. Switch to a window not focused by the previously visible cursor using the
> > keyboard.
> > 5. The window border will start flickering (looking like it gets unfocused
> > and focused rapidly in succession).
> > 6. The cursor will also start to flicker.
> > 7. Using the keboard to focus the window the cursor was focusing when
> > visible will stop the flickering. Moving the cursor (so that unclutter
> > displays it again) will also stop the flicker until unclutter hides it
> > again.
> >
> > This bug was introduced in changeset 1418 37e3b2a40f6f [2]. The problem is
> > that XSetInputFocus is called through the unfocus() function from focus().
> > As I'm not familiar with Xlib I'm not sure how to fix this bug, but I've
> > been able to pinpoint the erroneous code and disable the XSetInputFocus call
> > when unfocus() is called from focus().
> >
> > I've attached a patch against changeset 1477 aefd753cfe9b which does exactly
> > this. Note that this was made just to highlight which code path triggers the
> > described behavior and is not meant as a patch for fixing the bug.
> >
> > [1]: http://www.ibiblio.org/pub/X11/contrib/utilities/unclutter-8.README
> > [2]: http://code.suckless.org/hg/dwm/rev/37e3b2a40f6f
> >
> > --
> > Cheers,
> > Eivind Uggedal
> >
>

Have you looked at the man page for unclutter? There is an option
(-noevents or some such thing) that makes unclutter not send any X11
signals. This should fix your bug.
Received on Mon Aug 03 2009 - 14:13:28 UTC