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    <p>As Steve said, you basically want shared_ptr for the construction/destruction part. If you can't use boost, then I'd recommend copying the appropriate code from the boost headers (I believe the license allows this), or whatever other workaround you need to circumvent your dumb corporate policies. The other advantage of this approach is that when you can adopt TR1 or C++0x, you won't need do rewrite/maintain any custom implementation, you can just use the [then] built-in library code.</p> <p>As for the thread safety (which Steve didn't address), I find it's almost always a good idea to use synchronization primitives rather than trying to get it right yourself with custom locking. I'd suggest using a CRITICAL_SECTION, and then adding some timing code to make sure the total lock/unlock time is negligible. Doing a lot of lock/unlock operations is fine, as long as there's not too much contention, and you won't have to debug obscure threaded access issues.</p> <p>That's my advice, anyway, FWIW.</p> <p>Edit: I should add that once you're effectively using boost, you'll probably want to keep a weak_ptr in the MyObject class, so you can check if the extended object still exists on the "get" function without holding a reference to it. This will allow your "ref counted destruction" when no external caller is still using the instance. So, your "get" function looks like:</p> <pre><code>shared_ptr&lt; MyExtendedObject &gt; MyObject::GetExtentedObject(){ RIIALock lock( my_CCriticalSection_instance ); shared_ptr&lt; MyExtendedObject &gt; spObject = my_weak_ptr.lock(); if (spObject) { return spObject; } shared_ptr&lt; MyExtendedObject &gt; spObject = make_shared&lt; MyExtendedObject &gt;(); my_weak_ptr = spObject; return spObject; } </code></pre> <p>... and you don't need a release function, cause that part is done automatically through shared_ptr's reference counting. Hope that's clear.</p> <p>See: <a href="https://stackoverflow.com/questions/2160334/boost-weak-ptrs-in-a-multi-threaded-program-to-implement-a-resource-pool">Boost weak_ptr&#39;s in a multi-threaded program to implement a resource pool</a> for more info on weak_ptr and threading safety.</p>
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    1. POThread-safe lazy get and release
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    1. COThanks for your answer! But as I said I'm still waiting for a solution with shared_ptr that totally meets my needs. And for your information my lock unlock mechanism is implemented through critical sections.
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    2. COOk so for your EDIT, it should work and I had in the early stages a solution that was close to this: You still have a full lock for each GetExtentedObject call. My final intend was to fully get rid of locks when just the ref count is updated.
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    3. COI'd want to see this proven with timing output/etc. before I didn't use it. You're free to try to optimize it further and/or try to roll your own lock-free style implementation (which, as I said, I would not recommend), but if your locking time is non-negligible compared to your object initialization and other operations, perhaps you have other design problems.
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