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module Main where
import Control.Concurrent
import System.IO
import System.Process
main :: IO ()
main = do p <- foldl (>>=) (return stdin) (replicate 10 docat) >>= docat0
t <- myThreadId
-- timeout
forkIO $ do threadDelay 5000000; killThread t
waitForProcess p
putStrLn "end"
return ()
docat :: Handle -> IO Handle
docat hin = do
(_, Just hout, _, ph) <-
createProcess (proc "cat" []){ std_in = UseHandle hin,
std_out = CreatePipe }
return hout
docat0 :: Handle -> IO ProcessHandle
docat0 hin = do
(_,_,_,ph) <- createProcess (proc "cat" []){ std_in = UseHandle hin }
return ph
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