UNDER CONSTRUCTION
The cnd_wait() and cnd_timedwait() functions temporarily cede possession of a mutex so that other threads that may be requesting the mutex can proceed. These functions must always be called from code that is protected by locking a mutex. The waiting thread resumes execution only after it has been notified, generally as the result of the invocation of the cnd_signal() or cnd_broadcast() function invoked by another thread. The cnd_wait() function must be invoked from a loop that checks whether a condition predicate holds. A condition predicate is an expression constructed from the variables of a function that must be true for a thread to be allowed to continue execution. The thread pauses execution, via cnd_wait(), cnd_timedwait(), or some other mechanism, and is resumed later, presumably when the condition predicate is true and the thread is notified.
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