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*                        Unary Indirection operator;  Binary Multiplication

 *ptr                    Indirection (used as unary operator)
 ptr                     any pointer type or expression

 exp1 * exp2             Multiplication (used as binary operator)
 exp1                    any int or float expression
 exp2                    any int or float expression


    The * operator has two different meanings, depending upon its
    context.

    As a binary operator, * performs multiplication.  The result depends
    upon the operators and follows the usual arithmetic conversions.
    Here are two examples:

           i = 6 * 7;           /* i == 42 */
           x = 3.4 * 5;         /* x == 17.0 */

    As a unary operator, * dereferences a pointer; in other words, *ptr
    refers to the element pointed to by ptr. The argument for * is any
    pointer type or expression; the resulting expression is equivalent to
    an object of the type that ptr points to. Example:  a = *myptr;

  ------------------------- Pointers to Functions -------------------------

    Perhaps one of the more confusing pointers is the function pointer,
    which points to a function rather than to a data object.  It is much
    easier to use than to describe, so here is an example that shows all
    the steps for declaring and using a pointer to a function:

           int func1();               /* Declares func1() and func2()   */
           int func2();               /*   as functions returning int   */

           int (*funcptr)();          /* Declares funcptr as a pointer  */
                                      /* to a function returning an int */
           if (x < 2)
               funcptr = func1;       /* funcptr points to func1()      */
           else                                  /* or */
               funcptr = func2;       /* funcptr points to func2()      */

           i = (*funcptr)(10,3);      /* Call func1() or func2()        */

    The first two statements declare that func1() and func2() are
    functions (not variables) that return ints.  The next statement is
    the important one: it declares a pointer--funcptr--to a function; the
    function that funcptr points to returns an int.

    The if statement assigns the address of either func1() or func2() to
    funcptr. (Note that the name of a function is equivalent to the
    address of that function; just as the name of an array is equivalent
    to the address of the array.)  Finally, the last line makes a call to
    one of those two functions, with `10' and `3' as arguments. A pointer
    to a function is especially useful when you want to pass functions as
    arguments of a function.