It is written in LabVIEW (notice the .vi extension). You can see the source code of it by double clicking on it on the block diagram. This will open the front panel. You can then look at the block diagram for it.
LabVIEW code cannot be converted into C/C++. Why do you need to convert it to C?
I have a real-time embedded controller running on VME that I programmed via Vxworks. I need a C code version to run on-line system identification. Do you have any suggestion?
There is no way to convert LabVIEW code to C. What do you mean by running an on-line system identification? What hardware do you need it on?