If one thread owns a
timed_mutex object, attempts by another thread
to acquire ownership of that object will fail (for
try_lock()) or block
(for
lock(),
try_lock_for(), and
try_lock_until()) until
the owning thread has released ownership with a call to
unlock() or the
call to
try_lock_for() or
try_lock_until() times out (having
failed to obtain ownership)
.