Infinite serial listener in Haskell.

Serial.hs

import Control.Monad (forever)
import Control.Concurrent (forkIO, killThread)
import qualified Data.ByteString.Char8 as B
import System.Hardware.Serialport
    (openSerial, recv, closeSerial, defaultSerialSettings)

port = "COM1" -- Windows
--port = "/dev/ttyUSB0" -- Unix

main = do
    putStrLn "Press ENTER to exit."
    s <- openSerial port defaultSerialSettings
    t <- forkIO $ forever $ do
        recv s 1 >>= B.putStr
    _ <- getLine
    killThread t
    closeSerial s