Re: [Boost-users] [smart_ptr]intrusive_ptr suggestion

Subject: Re: [Boost-users] [smart_ptr]intrusive_ptr suggestion
From: gast128 (gast128_at_[hidden])
Date: 2010-08-12 10:56:32

Andrew Holden <aholden <at> charteroaksystems.com> writes:

> 
> On August 11, 2010 5:35 PM, gast128 wrote:
> > <snip>
> > 
> >> Perhaps you should initialize the reference count to zero in the 
> >> constructor of IFoo, instead of initializing it to 1.
> >> 
> >> In Christ,
> >> Steven Watanabe
> >
> > Yes but I think it is more natural that the ref count starts at 1 for a 
ref counted object. Thats at least the
> COM protocol
> 
> It's a slightly different situation. COM is designed for manual reference 
counting. It assumes that each
> raw pointer, including the one returned from the constructor, counts as a 
reference.  For boost intrusive
> pointers, the count is the number of intrusive pointers referencing the 
object.  Until you assign the
> object to one, that count is zero.

Not sure if this adresses my problem. intrusive_ptr is used in situations 
where the object or some other mechanism keeps tracking of its lifetime. 
intrusive_ptr only guarantees to call 'intrusive_ptr_add_ref' 
and 'intrusive_ptr_release' on construction and destruction of the 
intrusive_ptr.  The most used scenario is probably objects which are ref 
counted. The count doesn't need to be the number of intrusive_ptr's on the 
object; it can be larger than that.

Objects which start with a ref count of 1 get the previously described 
problem. Afaik is that also the most used scenario. Objects with reference 
count of 0 shouldnt be alive.