How to Use Arrays of Function Pointers

http://www.newty.de/fpt/fpt.html#defi




//-------------------------------------------------------------------------
// 2.8 How to Use Arrays of Function Pointers

// C ----------------------------------------------------------------------

// type-definition: 'pt2Function' now can be used as type
typedef int (*pt2Function)(float, char, char);

// illustrate how to work with an array of function pointers
void Array_Of_Function_Pointers()
{
printf("\nExecuting 'Array_Of_Function_Pointers'\n");

// define arrays and ini each element to NULL, and are arrays
// with 10 pointers to functions which return an int and take a float and two char

// first way using the typedef
pt2Function funcArr1[10] = {NULL};

// 2nd way directly defining the array
int (*funcArr2[10])(float, char, char) = {NULL};


// assign the function's address - 'DoIt' and 'DoMore' are suitable functions
// like defined above in 2.1-4
funcArr1[0] = funcArr2[1] = &DoIt;
funcArr1[1] = funcArr2[0] = &DoMore;

/* more assignments */

// calling a function using an index to address the function pointer
printf("%d\n", funcArr1[1](12, 'a', 'b')); // short form
printf("%d\n", (*funcArr1[0])(12, 'a', 'b')); // "correct" way of calling
printf("%d\n", (*funcArr2[1])(56, 'a', 'b'));
printf("%d\n", (*funcArr2[0])(34, 'a', 'b'));
}