#include <stdio.h>   /* printf         */
#include <string.h>  /* strcpy, strcat */
#include <windows.h> /* DLL stuff      */

/* conveniences for casting */
typedef void (*PRINTME)(const char *);
typedef int (*ADD)(int, int);

int main(void)
{
  const char *soname = "hello";   /* base name of a .dll or .so */
  const char *fname1 = "printme"; /* function to call (text)    */
  const char *fname2 = "add";     /* function to add (text)     */

  PRINTME printme; /* void printme(const char *) */
  ADD add;         /* int add(int, int)        */
  HANDLE lib;      /* library handle           */
  int result;     /* result of the addition   */

  char buffer[100]; /* used to build the filename */

    /* decorate the filename: hello ==> hello.dll */
  strcpy(buffer, soname);
  strcat(buffer, ".dll");

    /* load the shared library */
  lib = LoadLibrary(buffer);
  if (!lib)
  {
    printf("Unable to load DLL: %s\n", buffer);
    return -1;
  }

    /* get print function and call it */
  printme = (PRINTME)GetProcAddress(lib, fname1);
  if (!printme)
    printf("Function not found: %s\n", fname1);
  else
    printme("Print this!");

    /* get add funtion and call it */
  add = (ADD)GetProcAddress(lib, fname2);
  if (!add)
    printf("Function not found: %s\n", fname2);
  else
  {
    result = add(10, 20);
    printf("The sum is: %i\n", result);
  }

    /* library no longer needed */
  FreeLibrary(lib);

  return 0;
}

Hello from library: Print this!
The sum is: 30