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import System.IO
import Control.Exception
import qualified GHC.IO.Device as IODevice
import GHC.IO.Handle
import GHC.IO.Handle.Internals
import GHC.IO.Handle.Types
import System.Posix.Internals
main = do
h <- openFile "hClose002.tmp" WriteMode
-- close the FD without telling the IO library:
naughtyClose h
-- first hClose will raise an exception, but close the
-- Handle anyway:
showPossibleException (hClose h)
-- second hClose should success (Handle is already closed)
showPossibleException (hClose h)
-- this should succeed (checking that the lock on the file has
-- been released:
h <- openFile "hClose002.tmp" ReadMode
showPossibleException (hClose h)
showPossibleException (hClose h)
showPossibleException :: IO () -> IO ()
showPossibleException f = do e <- try f
print (e :: Either SomeException ())
naughtyClose h =
withHandle_ "naughtyClose" h $ \ Handle__{haDevice=dev} -> do
IODevice.close dev
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