multiple sketchfolders ?

Hello,

is there a way to set, which should be the sketchfolder during startup.
In other words, can i use different sketchfoldesr and start Arduino-IDE with the
sketchfolder path as argument or in startscript ?

Why do you want to do that? Sounds pretty useless to me...

But if you want to, you can change the preferences.txt file with a script or something.

You should be able to do this with --pref name=value or --preferences-file filename see Arduino/manpage.adoc at master · arduino/Arduino · GitHub for details.