Benefits of pointers?

Question

I recently developed an interest in C programming so I got myself a book (K&R) and started studying.

Coming from a University course in Java (basics), pointers a

Answer 1

Your highlighted rule is very wise. It will keep you out of trouble but sooner or later you have to learn pointers.

So why do we want to use pointers?

Say I opened a textfile and read it into a giant string. I can't pass you the giant string by value because it's too big to fit on the stack (say 10mb). So I tell you where the string is and say "Go look over there at my string".

An array is a pointer ( well almost ).

int[] and int* are subtly different but interchangeable for the most part.

int[] i = new int[5]; // garbage data
int* j = new int[5]   // more garbage data but does the same thing
std::cout << i[3] == i + 3 * sizeof(int); // different syntax for the same thing

A more advanced use of pointers that's extremely useful is the use of function pointers. In C and C++ functions aren't first class data types, but pointers are. So you can pass a pointer to a function that you want called and they can do so.

Hopefully that helps but more than likely will be confusing.