[dmd-concurrency] Sending mesages to non-listening threads

[Andrei Alexandrescu]

Sean Kelly wrote:
> There are a bunch of things still missing from the current API that will need to be addressed at some point though, like linking threads (so one will be notified if the other exits), a Tid registery, and probably a bunch of other things I'm forgetting offhand.  These aren't necessary for a first cut, but they'll have to be added soon after.

Yah, please do mention everything you remember. I want to describe a 
reasonably complete API.

Andrei