How Can I Delete Memory Created By New Without Using Delete Operator

Question

1.00/5 (2 votes)

See more:

C++

int *ptr;
ptr=new int a[20];

delete memory created to 20 integers without using delete

Posted 1-Oct-14 3:33am

Member 11123171

Add a Solution

Comments

Richard MacCutchan 1-Oct-14 9:37am

You can't. As I suggested in your other question, go and read your course notes.

Rob Grainger 1-Oct-14 11:58am

Of course you could use a smart pointer...

std::auto_ptr<int> a(new int[20]);

Which will automatically delete the memory when the variable 'a' goes out of scope. But really that's still calling delete[] under the covers.

Note - you need to use delete[] rather than delete to free an array.

2 solutions

Add a Solution

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

CubbiMew · Accepted Answer · 2014-10-01T16:53:00

You could use a number of ways to to do it without literally writing the delete operator in your program:

C++

#include <memory>
int main()
{
    int *ptr=new int[20];
    std::allocator<int>().deallocate(ptr, 20);
}

C++

#include <memory>
int main()
{
    int *ptr=new int[20];
    std::default_delete<int[]>()(ptr);
}

XML

#include <memory>
int main()
{
    int *ptr=new int[20];
    std::unique_ptr<int[]> p(ptr);
}

XML

#include <boost/smart_ptr.hpp>
int main()
{
    int *ptr=new int[20];
    boost::scoped_array<int> p(ptr);
}

etc.

All of these somewhere internally execute delete[] with a copy of your ptr as the argument which is what actually deallocates that memory.

KarstenK · Accepted Answer · 2014-10-01T05:59:00

the language C++ has some rules, for instance that memory which is allocated the new has to be freed with release.

You can:

1. overwrite the command new and delete with your own implementation
2. use other methods for memory managment like malloc and free.
3. allocate memory in scopes.
4. use some auto_ptr. (advanced technology)

But never ever ferget: be a good citizen and if you want to develop software you should stick to the rules.

How Can I Delete Memory Created By New Without Using Delete Operator

2 solutions

Solution 2

Solution 1

Add your solution here

Preview 0

How Can I Delete Memory Created By New Without Using Delete Operator

2 solutions

Solution 2

Solution 1

Add your solution here

Preview 0

Existing Members

...or Join us