KDE4 apps don't launch

[Ian Wadham]

On 29/07/2011, at 3:19 AM, Doug McComber wrote:
> I've installed Digikam and consequently KDE4.  However no KDE apps
> will launch.  They all exhibit the same symptom (bouncing in the dock
> for a while and not responding).

Lucky you.  I am having trouble getting Digikam to build, but have put
the problem on the back-burner for now.

I have just succeeded in getting a SVN checkout of KDE Games trunk
working, outside Macports, but setting various paths and env variables
to use a combination of my own source-code and build setup with KDE
and Qt libraries from Macports.  I am a KDE Games developer and wanted
to see how the latest versions would go on the Mac.

At first I noticed the bouncing in the dock and "not responding" behaviour
and was Force Quitting apps and trying various things, such as running
"open" on the command-line and even "/Applications/KDE4/x.app/Contents/MacOS/x"
(i.e. direct use of the executable of "x.app").  After a few tries, the apps
started to run and now they always run, whatever method I use.

I think this was because KDE games (and maybe also Digikam) do a fair bit
of graphics loading, rendering and caching before they start for the first time
on a platform and were getting more of that done each time I tried.  Mac OS X
apparently does not like such things and after a while flags the app as "not
responding".  Am I correct in this assumption?

> I've followed everything about KDE4 and Mac that I can find.   While
> googling I found this older post from the list:
> 
>     There's a bug in the way KDE4 is handled currently; I don't know what
>     the correct fix is, but my current hack involves some launchd actions
>     that create the necessary directories and symlinks thereto in
>     ~/Library/Preferences/KDE.
> 
>         ln -s /var/tmp/kdecache-$USER $HOME/Library/Preferences/KDE/cache-$HOST
>         ln -s $TMPDIR/ksocket-$USER $HOME/Library/Preferences/KDE/socket-$HOST
>         ln -s $TMPDIR/kde-$USER $HOME/Library/Preferences/KDE/tmp-$HOST
> 
> 
> I have the first symlink.  The second and third  (ksocket and kde)
> were there but were linked to non-existent directories.  Using find
> from the terminal I couldn't find a ksocket-* or kde-* directory
> anywhere.
> 
> What part of KDE should I possibly re-build via Macports to fix this?

Brandon has already replied to this.  The initial barriers to getting KDE apps to
run appear to be:

 - Getting the links to sockets and temp dirs correct (on a Linux system, KDE does
    that automagically),
 - Getting dbus to run (also automagical on Linux),
 - Getting kdeinit4 to run (some KDE apps seem to require it, others not).

I would like to find out more about the KDE desktop eco-system, how best to fake it
on Mac OS X and how much of it really needs to be faked.  As a KDE developer,
the innards of the desktop have been mystifying me for years, ever since the advent
of KDE 4.  I will try to get some pointers on a KDE developers' mailing list.

I also need to find out more about how Mac OS X starts up applications and would
appreciate some pointers, hints or links from this list.  I am new to the Mac.  For example,
where do stdout and stderr go when you do "open x.app" in a Terminal?

I believe it would be worthwhile to build up a complete picture of how KDE apps
should run in a Mac OS X environment and then enshrine that in the Macports
Wiki or HowTo's, if not in Macports itself.

There really are some excellent apps in KDE, such as KMyMoney, Digikam and
the KDE Edu suite, not to mention KDE Games ... :-) ... and IMHO it would be well
worth making sure these become easier to get running from Macports.

All the best, Ian W.