[isabelle-dev] Problems with Fedora

[Makarius]

On Wed, 11 Sep 2013, Makarius wrote:

> On Fri, 6 Sep 2013, Christian Sternagel wrote:
>
>> My exact Fedora version is Fedora 19 64-bit with GNOME 3.8.2.
>
> I have made a few attempts to install that somewhat rough Linux distribution, 
> either virtually or physically, but did not get very far. One virtual 
> installation did not work after Virtualbox guest extensions were installed, 
> another physical install did not work due to Fedora not liking my UEFI 
> laptop. I will try again, maybe with some older machine.

Trying on that older machine I had first wrecked my Ubuntu 12.04 LTS, but 
it is now back at Xubuntu 13.04.  Trying harder on the UEFI laptop again, 
I actually managed: Fedora 19 running smoothly on 4 core i7 and 
accelerated Intel graphics.

And I've also managed to reproduce the keyboard focus loss once or twice, 
but it is hard to get it again after the machine has "warmed up". It seems 
that the application simply fails to get more keyboard input, 
independently of the complex Swing GUI component focus scheme (popups 
etc.).


Doing some web search while trying, I've found suspicious problem reports 
like this:

   iBus breaks keyboard input for java apps -- Feb 21, 2012
   http://code.google.com/p/ibus/issues/detail?id=1417

It seems that the environment variable XMODIFIERS controls such input 
methods. On my Xununtu it is unset, but on Fedora it refers to ibus.


So if you still get the keyboard focus loss reliably, you can try the 
following in $ISABELLE_HOME_USERS/etc/settings:

   unset XMODIFIERS

or

   XMODIFIERS=""

If that improves the situation, I could make this a factory default of 
Isabelle/jEdit on Linux.  We will see during several weeks of testing of 
release candidates if it works for most users, or causes other problems.


 	Makarius