/usr/include/boost/interprocess/sync/ is in libboost1.46-dev 1.46.1-7ubuntu3.
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/usr/include/boost/interprocess/sync/emulation/
/usr/include/boost/interprocess/sync/emulation/interprocess_barrier.hpp
/usr/include/boost/interprocess/sync/emulation/interprocess_condition.hpp
/usr/include/boost/interprocess/sync/emulation/interprocess_semaphore.hpp
/usr/include/boost/interprocess/sync/emulation/mutex.hpp
/usr/include/boost/interprocess/sync/emulation/named_creation_functor.hpp
/usr/include/boost/interprocess/sync/emulation/recursive_mutex.hpp
/usr/include/boost/interprocess/sync/file_lock.hpp
/usr/include/boost/interprocess/sync/interprocess_barrier.hpp
/usr/include/boost/interprocess/sync/interprocess_condition.hpp
/usr/include/boost/interprocess/sync/interprocess_mutex.hpp
/usr/include/boost/interprocess/sync/interprocess_recursive_mutex.hpp
/usr/include/boost/interprocess/sync/interprocess_semaphore.hpp
/usr/include/boost/interprocess/sync/interprocess_upgradable_mutex.hpp
/usr/include/boost/interprocess/sync/lock_options.hpp
/usr/include/boost/interprocess/sync/mutex_family.hpp
/usr/include/boost/interprocess/sync/named_condition.hpp
/usr/include/boost/interprocess/sync/named_mutex.hpp
/usr/include/boost/interprocess/sync/named_recursive_mutex.hpp
/usr/include/boost/interprocess/sync/named_semaphore.hpp
/usr/include/boost/interprocess/sync/named_upgradable_mutex.hpp
/usr/include/boost/interprocess/sync/null_mutex.hpp
/usr/include/boost/interprocess/sync/posix/
/usr/include/boost/interprocess/sync/posix/interprocess_barrier.hpp
/usr/include/boost/interprocess/sync/posix/interprocess_condition.hpp
/usr/include/boost/interprocess/sync/posix/interprocess_mutex.hpp
/usr/include/boost/interprocess/sync/posix/interprocess_recursive_mutex.hpp
/usr/include/boost/interprocess/sync/posix/interprocess_semaphore.hpp
/usr/include/boost/interprocess/sync/posix/pthread_helpers.hpp
/usr/include/boost/interprocess/sync/posix/ptime_to_timespec.hpp
/usr/include/boost/interprocess/sync/posix/semaphore_wrapper.hpp
/usr/include/boost/interprocess/sync/scoped_lock.hpp
/usr/include/boost/interprocess/sync/sharable_lock.hpp
/usr/include/boost/interprocess/sync/upgradable_lock.hpp
/usr/include/boost/interprocess/sync/xsi/
/usr/include/boost/interprocess/sync/xsi/advanced_xsi_semaphore.hpp
/usr/include/boost/interprocess/sync/xsi/simple_xsi_semaphore.hpp
/usr/include/boost/interprocess/sync/xsi/xsi_named_mutex.hpp