Alex Rivera | Logout

Is it wrong to use auto_ptr with new char[n]

Asked 2008-11-04T09:31:06.857
14

If I declare a temporary auto deleted character buffer using

std::auto_ptr<char> buffer(new char[n]);

then the buffer is automatically deleted when the buffer goes out of scope. I would assume that the buffer is deleted using delete.

However the buffer was created using new[], and so strictly speaking the buffer should be deleted using delete[].

What possibility is there that this mismatch might cause a memory leak?

c++ stl memory-leaks auto-ptr
Edit
Report

1 Answer

10

I would use a vector of char as the buffer.

std::vector<char>    buffer(size);

read(input,&buffer[0],size);

Basically you don't even want to call new if you don't need to.
A vector provides a run-time sized buffer that you can use just like an array (buffer).

The best part is that the vector cleans up after itself and the standard guarantees that all element in the vector will be in contigious storage. Perfect for a buffer.

Or more formaly the guarantee is:

(&buffer[0]) + size == (&buffer[size])
answered 2008-11-04T18:12:11.190

Your Answer