This is Microsoft C Compiler used in Microsoft Visual C++ 6.0
With it you can manually compile most any program if you're serious about it,
modify the batch file to your needs.
There is a sample 'hello-world' app there so you can test the compiler, it compiles just fine simply run the batch script but make sure it has the path to the 'include' folder inside of the MSVC6Compiler folder specified CORRECTLY!