#define PathToLibrary "D:\\NativeLibrary.dll"

#include "windows.h"
#define symLoad GetProcAddress
#include <stdlib.h>
#include <stdio.h>

int callSumFunc(char* path, char* funcName, int a, int b);

int main()
{
    if (!access(PathToLibrary, 0))
        printf("File Present");
    else
        printf("File not Found");

    // Sum two integers
    int sum = callSumFunc(PathToLibrary, "add", 2, 8);
    printf("The sum is %d \n", sum);
}

int callSumFunc(char* path, char* funcName, int firstInt, int secondInt)
{

    // Call sum function defined in C# shared library
    HINSTANCE handle = LoadLibrary(PathToLibrary);
    DWORD ErrorCode = GetLastError();

    typedef int (*myFunc)();

    myFunc MyImport = (int)symLoad(handle, funcName);

    int result = MyImport(firstInt, secondInt);

    // CoreRT libraries do not support unloading
    // See https://github.com/dotnet/corert/issues/7887
    return result;
}