Memory help

[dAND3h]

Hi, well , I have a function which returns a pointer. Lets call it function 1.
So, inside another function(function 2) I call a 3rd function, using function1 as one of the paramaters. But the problem is, once that I pass the function2 into function 3 I don't want the allocated memory from function2 anymore. How to delete it?

So, like this:

pointer* function1()//returns a pointer
{

 return pointer;
}
void function2()//uses this pointer to call function 3
{

function3(*function1());
//I need to delete the pointer when it returns here, how do I do it?
//If I do delete[]function1(); will that run the function again and create //ANOTHER pointer and delete it, thus leaving the original pointer intact?

}
void function3(ref&)//uses the pointer to do stuff
{
//do stuff
//**Is it possible to delete a pointer using the reference?**//
}

I hope I explain nicely...

[quirkyusername]

Is it possible to delete a pointer using the reference?

No you can only delete that memory using the pointer

[Mathes]

im not sure if i get this right.
but why dont you save the pointer function1 gives you in a variable?

void function2()//uses this pointer to call function 3
{
    type *ptr = function1();
    function3(ptr);
    delete ptr; //or delete[] if the pointer memory was allocated with new[]
}

[dAND3h]

Will that not just make the new pointer, point to the same place as function1(), therefore the function1() pointer will still be hanging about?

[Mathes]

yeah, my solution above wasnt working as i thought it would. you were right there.
but you could try std::auto_ptr. it takes care of deleting the allocated memory for you.
if you want to use some STL stuff, auto_ptr does not work... (maybe you want to check out boost::shared_ptr, www.boost.org)

#include <iostream>
#include <memory>
using std::cin;
using std::cout;
using std::endl;

std::auto_ptr<char> function1()
{
	std::auto_ptr<char> ptr(new char);
	cout << &ptr << "- in function1" << endl;
	return ptr;
}

void function3(std::auto_ptr<char> &ptr)
{
	cout << &ptr << "- in function3" << endl;
}

void function2()
{
	std::auto_ptr<char> ptr(function1());
	cout << &ptr << "- in function2" << endl;
	function3(ptr);
	cout << &ptr << "- in function2" << endl;
}


int main(){
	function2();
	return 0;
}

if you run the program it will print the adress of each auto_ptr. always the same, and when function2 is left, the pointer will be deleted automaticly. (oh i hope im not mixing stuff up here... :-/ )