Well, it's a hint (but then so is `nice`), so it doesn't have any strict postcondition. The meaning of the hint would be that the process won't make good use of

Well, it's a hint (but then so is `nice`), so it doesn't have any strict postcondition. The meaning of the hint would be that the process won't make good use of CPU cycles at present, and it would be preferable to yield to any other processes now, rather than being preempted later when it are busy.