Re: Better way of allocating a memory( auto_ptr vs new vs malloc)

From:

James Kanze <james.kanze@gmail.com>

Newsgroups:

comp.lang.c++

Date:

Mon, 8 Dec 2008 01:32:53 -0800 (PST)

Message-ID:

<de61a8f4-abe6-4e8c-b833-bc470f4981e5@j11g2000yqg.googlegroups.com>

On Dec 7, 3:46 pm, Ami <Amit.Bas...@gmail.com> wrote:

On Dec 7, 5:32 pm, Ami <Amit.Bas...@gmail.com> wrote:

This is what I have now .. to overcome the flaw of passing by
value ...

What's the "flaw" of passing by value? If your types have value
semantics, it's usually what you want.

Now I have
int main ()
   {
       auto_ptr<T>p = (new T()) ;
       func(p); // appending get() wont work in a function call
       p.release();
       return ( EXIT_SUCESS);
   }
   void func(const auto_ptr<T> &output)
   {
     output->do_Something();
   }

works just fine..
Can you please let me know if this is the best way of passing
auto_ptr by reference and avoiding any leaks ?

In general, I don't like passing references to auto_ptr. Either
the called function is going to take over ownership, and passing
the auto_ptr by value would seem to be indicated, or it's not,
and either derferencing the auto_ptr to pass by reference, or
calling get to pass by pointer, would seem more appropriate.

also why get() doesnt work in a function call func(p.get()) //
throws error

What is the signature of func? If func takes a T* (or a T
const*), then p.get() should work.

--
James Kanze (GABI Software) email:james.kanze@gmail.com
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