The main() function could be in any of the source files.

What I find puzzling is that these seem to be C files. I.e. files ending with .c are usually passed to the C compiler (e.g. gcc on Linux), usually they won't compile at all if they contain C++ code.

In any case have a look at the compile step output, the compiler calls are usually very explicit where the output file is.

Cheers,
_