Pointer vs. variable, Objective-C

count refers to the VALUE of the variable. You don't want to assign the value of count to intptr, you want to assign the address of count. Thus the & operator is used.

If you do intptr = count, you'd be pointing to memory address 10 in this case, which is sure to be in system memory, not your application memory and you'd crash.

It is important to understand that pointers have actually a different data type.

A int variable will hold integer values.

A pointer variable will hold memory addresses.

So it is not right to assign an int variable to a pointer variable (as you suggested intptr = count;)

I believe using a typedef could help you better understand the difference.

Here's a small example:

#include <stdio.h>

typedef int* int_pointer;

int main() {

    int n; // integer
    int_pointer p; // pointer

    n = 5;

    p = &n; // p's value is now n's address

    *p = *p + 1; // add 1 to the value stored at the location that p points to
                 // and put that value back in the same location

    printf("n = %d\n", n);
    printf("*p = %d\n", *p);

    return 0;
}

This program will print

n = 6
*p = 6