Pointing to functions : Function Pointer « Function « C Tutorial

1. C Tutorial
2. Function
3. Function Pointer

#include <stdio.h>

int sum(int x, int y)
{
  return x + y;
}


int product(int x, int y)
{
  return x * y;
}


int difference(int x, int y)
{
  return x - y;
}


int main(void)
{
  int a = 10;
  int b = 5; 
  int result = 0;
  int (*pfun)(int, int);              /* Function pointer declaration      */

  pfun = sum;             
  result = pfun(a, b);                /* Call sum() through pointer        */
  printf("\npfun = sum             result = %d", result);

  pfun = product;         
  result = pfun(a, b);                /* Call product() through pointer    */
  printf("\npfun = product         result = %d", result);

  pfun = difference;      
  result = pfun(a, b);                /* Call difference() through pointer */
  printf("\npfun = difference      result = %d\n", result);
  return 0;
}

pfun = sum             result = 15
     pfun = product         result = 50
     pfun = difference      result = 5