Thank you for your answers. I appreciate that very much. Its a bit funny but i don't use c in this context.
The problem I have is that it didn't work with the flag -d: release. I have now tried something out and found out the following: When I create the stream from the previously opened file, these errors occur in the release build, but when I create a new stream from filepath, the program works fine broken: stream = newFileStream(FILE) ... stream.setPosition(blabla) Run working solutiuon: stream = newFileStream(filename) ... stream.setPosition(blabla) Run I'm not sure, maybe I still have a worm somewhere, but when I open the stream from the path it seems to work. It is still strange that it does not work with the stream from the FILE