Changing the Value of Pointers Passed as Arguments

Introduction

Our goal is to change the value of a pointer passed as an argument to a function. To be clear, we don’t want to change the variable that the pointers point to (with the dereference operator). We want to change the pointer itself and make it point somewhere else.

As a starting point, we’ll write a function called setToNULL, which receives an int pointer and sets it to NULL.

First attempt

Well, if we want to set a pointer to NULL, we usually do:

pointer = NULL;

Therefore, let’s try the same thing, but in a function. We’ll create a pointer, assign it a valid memory address, and then call a function to try to set it to NULL.