template <class Rep, class Period> void sleep_for (const chrono::duration<Rep,Period>& rel_time);
Sleep for time span
Blocks execution of the calling thread during the span of time specified by rel_time.
The execution of the current thread is stopped until at least rel_time has passed from now. Other threads continue their execution.
The time span after which the calling thread shall resume its execution.
Note that multi-threading management operations may cause certain delays beyond this. duration is an object that represents a specific relative time.