如何将数据从protobuf-embedded- C传输到谷歌protobuf c++ /Java库?

I am using protobuf-embedded-c on a small system to transfer different data from the it to a PC. The problem is, that if I use the embedded library on both ends everything works. If i use the google C++ on the PC it doesn't work anymore. I think i traced the problem to the embedded library having length prefixes in every message, but i cannot seem to do this in a good way on the C++ library. Here is the test application which i used to debug this: on a small syste