Why is my pointer not null after free?

Question

void getFree(void *ptr)
{
    if(ptr != NULL)
    {
        free(ptr);
        ptr = NULL;
    }
    return;
}
int main()
{
char *a;
a=malloc(10);
getFree(a);
if(a==         


        

Answer 1

The question has already been answered but if it helps, I can explain it graphically.

You are doing this --> the pointer is copied by value to your function so it points to the array

but instead you want this -->point to the original pointer

As Merlyn Morgan-Graham already said, the way to solve it is to add operators * and &.