A mutex object facilitates protection against data races and allows safe synchronization of
data between execution agents (
[thread.req.lockable])
.An execution agent
owns a mutex from the time it successfully calls one of the
lock functions until it calls unlock
.Mutexes can be either recursive or non-recursive, and can
grant simultaneous ownership to one or many execution agents
.Both
recursive and non-recursive mutexes are supplied
.