PS. From now on, messages on this forum will be cross-posted to the Kojo-User or Kojo-Dev google group.

Thanks for your concrete answers.

You're welcome.
So, things look under control now?

Good to know about your plans!

I will use the english version of Kojo during the first weeks in the first programming course in our media informatics program for teaching imperative programming.
Besides that we will use the german Kojo variant on 13th of june for short kids programming courses during the Berlin "Long Night of Sciences".

as from monday I will teach a full student group of 48 persons using Kojo.

What kind of class will this be? Computer science? Software engineering? Kojo visual programming stuff?

1) For what do we need the ~/.kojo/lite/libk directory?

Any jar in that directory will be on the classpath for scripts run within Kojo. So if you want to play with a third-party lib in Kojo, you can put its jar in the libk directory. By default the libk directory is empty.

2) As we don't have a ~ directory on Windows, is it taken from the environment variable
USERPROFILE (Windows user home directory) or the Java system property -Duser.home?

def homeDir = System.getProperty("user.home")

3) Would it work to collect the files from ${user.home}\.kojo\lite\libk by the same batch
script?

Yeah, that should work fine.

4) If so should I collect only .jar files from this directory?

Yes.

BTW: Where should I report issues? Here or on https://code.google.com/p/kojo/issues/list

Google code is getting phased out. Please report issues here:
https://bitbucket.org/lalit_pant/kojo/issues

1) For what do we need the ~/.kojo/lite/libk directory?

2) As we don't have a ~ directory on Windows, is it taken from the environment variable USERPROFILE (Windows user home directory) or the Java system property -Duser.home?
This is important as on our installation we have a separate area for each user, to which points only -Duser.home.

3) Would it work to collect the files from ${user.home}\.kojo\lite\libk by the same batch script?

4) If so should I collect only .jar files from this directory?

BTW: Where should I report issues? Here or on https://code.google.com/p/kojo/issues/list

Thanks again,
Christoph

Indeed, net.kogics.kojo.lite.DesktopMain actively works to disallow multiple instances. You can use net.kogics.kojo.lite.Main. That should work fine, other than a couple of limitations (the environment variable KOJO_CLASSPATH and the jars in the ~/.kojo/lite/libk directory will not be on the Kojo instance's classpath). You can ignore the connection exception.

Let me know if you run into any problems with this approach.

/L

C:\Program Files (x86)\Kojo2\lib>java -cp ;AppleJavaExtensions.jar;autocomplete.jar;docking-frames-common.jar;docking-frames-core.jar;geogebra.jar;geogebra_algo
s.jar;geogebra_cas.jar;geogebra_export.jar;geogebra_gui.jar;geogebra_javascript.
jar;geogebra_main.jar;geogebra_properties.jar;group-panel.jar;h2.jar;httpunit.ja
r;image-filters.jar;jdi.jar;jfugue.jar;jl1.0.1.jar;jlatexmath.jar;js-1.6R5.jar;j
ssc.jar;jtidy-4aug2000r7-dev.jar;jts.jar;kojo2.jar;piccolo2d-core.jar;piccolo2d-
extras.jar;rithica.jar;rstaui.jar;rsyntaxtextarea.jar;scala-actors.jar;scala-com
piler.jar;scala-library.jar;scala-parser-combinators.jar;scala-reflect.jar;scala
-swing.jar;scala-xml.jar;scalariform.jar;table-layout.jar net.kogics.kojo.lite.D
esktopMain
[INFO] Running > first Kojo instance with args: []
[INFO] Connecting (via RMI) with args: [] to already running Kojo instance
[INFO] Kojo Launcher Done.

Is there perhaps a command line option for Kojo to avoid connecting to an already running instance?
In our lab all students have their own account, but as they are running on the same server there could be a port conflict.

we have a Windows Terminal Server at Beuth University of Applied Sciences. Students log into it from client computers.
Only the first one starting Kojo by the Start menu succeeds. For all subsequent trials we only see a second-lasting hourglass, which diappears without a message. After exiting the first Kojo instance, another instance can be started.
As we do not know this behavior from other Java applications we suppose the little kojo.exe to be guilty.
In the Kojo2\bin directory there is a shell script for starting Kojo. It collects all .jar files from Kojo2/lib.
Do you have an equivalent script as Windows batch file for trying a workaround?
Or how could we diagnose, why only the first Kojo instance can start?

Thank you very much,
Christoph