gistfile1.lhs

-- | Register a timeout in the given number of milliseconds.
registerTimeout :: EventManager -> Int -> TimeoutCallback -> IO TimeoutKey
registerTimeout mgr ms cb = do
  key <- newUnique (emUniqueSource mgr)
  now <- getCurrentTime
  let expTime = fromIntegral ms / 1000.0 + now
  _ <- atomicModifyIORef (emTimeouts mgr) $ \q ->
       let q' = Q.insert key expTime cb q in (q', q')
  wakeManager mgr
  return $! TK key