libraries/base/tests/IO/hReady002.hs


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-- test for bug #4078
import System.IO
import Control.Concurrent
import System.Exit

main = do
  m <- newEmptyMVar
  forkIO $ do threadDelay 500000; putMVar m Nothing
  forkIO $ do hReady stdin >>= putMVar m . Just
  takeMVar m >>= print