    boost::thread reader(simple_reading_thread(rw_mutex,finish_mutex,unblocked_mutex,unblocked_count));
    boost::thread::sleep(delay(1));
    CHECK_LOCKED_VALUE_EQUAL(unblocked_mutex,unblocked_count,1u);

    boost::system_time const start=boost::get_system_time();
    boost::system_time const timeout=start+boost::posix_time::milliseconds(500);
    boost::posix_time::milliseconds const timeout_resolution(50);
    bool timed_lock_succeeded=rw_mutex.timed_lock_shared(timeout);
    BOOST_CHECK(boost::get_system_time()<timeout);
    BOOST_CHECK(timed_lock_succeeded);
    if(timed_lock_succeeded)
    {
        rw_mutex.unlock_shared();
