Ok... two things.

1) I suck at searching, because there is a TaskCondition. It seems a bit heavyhanded for me, though.
2) I could probably use yield() as the docs say:

Calling this function in short intervals is recommended if long CPU computations are carried out by a task. It can also be used in conjunction with Signals to implement cross-fiber events with no polling.

Are there any examples for this?

Thanks,
Drasha