How to implement thread safe reference counting in C++

c++ multithreading atomic reference-counting
Fabian picture Fabian · Sep 18, 2008 · Viewed 16.5k times · Source

How do you implement an efficient and thread safe reference counting system on X86 CPUs in the C++ programming language?

I always run into the problem that the critical operations not atomic, and the available X86 Interlock operations are not sufficient for implementing the ref counting system.

The following article covers this topic, but requires special CPU instructions:

http://www.ddj.com/architect/184401888

Answer

Michael Burr picture Michael Burr · Sep 18, 2008

Nowadays, you can use the Boost/TR1 shared_ptr<> smart pointer to keep your reference counted references.

Works great; no fuss, no muss. The shared_ptr<> class takes care of all the locking needed on the refcount.

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