Yield function for schedulers

[Aidan63]

It seems like most OS' and event loops have yielding be a bit more involved than just "bounce through the scheduler", e.g.

Win32 (Sleep)

A value of zero causes the thread to relinquish the remainder of its time slice to any other thread that is ready to run. If there are no other threads ready to run, the function returns immediately, and the thread continues execution.

Linux (sched_yield)

If the calling thread is the only thread in the highest priority list at that time, it will continue to run after a call to sched_yield().

WxWidgets Event Loop (wxEventLoopBase::Yield(bool onlyIfNeeded = false))

Yields control to pending messages in the windowing system.

If someone was creating a custom scheduler and wanted functionality like this they could just treat scheduling with a time of zero as a yield, but maybe it makes sense to have a abstract yield function on the scheduler?

[Simn]

I doubt that this distinction is very relevant in user code. It might impact the scheduler I suppose, but then the question is if a zero delay should really behave differently than a yield. In fact, the Win32 part you paste suggests that it should be the same.

[Simn]

Closing this because unless something comes up, I really think we can treat schedule(0) as a yield for cases where it matters, in case we ever find such cases.