refcount - "mostly" lock-free word-based atomic reference counting
refcount_h – core library header file.
refcount_libinit() – initialize the refcount library.
refcount_init(…) – initialize a refcount_t object.
refcount_state_load_depends(…) – load state pointer (basic thread-safety).
refcount_add_load_strong(…) – add and load reference (strong thread-safety).
refcount_sub_strong(…) – subtract reference (strong/basic thread-safety).
refcount_add_swap_weak(…) – add and swap reference (strong/basic thread-safety).
refcount_add_weak (…) – add reference (basic thread-safety).
http://appcore.home.comcast.net/
(portable lock-free data-structures)