[Nbd] Question re reference server implementation

[Alex Bligh <alex@...872...>]

I note the reference server implementation has a mainloop() (not threaded)
which appears never to be called.

I'm guessing this is because mainloop_threaded() was added and it
needs clearing up; or perhaps it's there for some other reason
(e.g. restoring functionality to platforms without g_threadpool
support?). In any case, if we add new features, are we meant to
add them to mainloop() as well, and if so how does it get tested?

-- 
Alex Bligh