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std::auto_ptr in c++

Automatic Pointer [deprecated]
Note: This class template is deprecated as of C++11 and completely removed in c++ 17. unique_ptr is a new facility with a similar functionality, but with improved security (no fake copy assignments), added features (deleters) and support for arrays.


auto_ptr objects have the uniqueness of taking ownership of the pointers allotted to them: An auto_ptr object that has ownership over one element is in charge of destroying the element it points to and to deallocate the memory allocated to it when itself is destroyed. The destructor does this by invoking operator delete automatically.

Hence, no two auto_ptr objects should own the same element, since together would try to destruct them at some point. When an assignment operation takes place between two auto_ptr objects, ownership is transferred, which means that the object losing ownership is set to no longer point to the element (it is set to the null pointer).




#include
void memory_leak() 
{
std::auto_ptr ptrClassA_1(new ClassA);
        std::auto_ptr ptrClassA_2 = ptrClassA_1; // ownership gets tranfered from ptrClassA_1 to ptrClassA_2
...
}

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