Ive studied those links provided and they helped me sort out some of my issues, but im still not getting how to link the files together, without defining stuff multiple times..
i have a couple of structures containing my modifiable data, witch i want to modify from different functions.
Now, i moved my structures to a "struct.h" file, and split up my functions to their respecive header files (like "inputs.h", "outputs.h", "display.h" and so on.
But since i now have to write to "struct.h" from multiple separate header files, i now have to include the "struct.h" into each header file, else i get compile errors within that file.
But when i try to compile the main project, i get "this and that was was re-defined" and so on.
So im still not getting how to link the different files together and how to access data across files.
Could anyone care to enlighten me?