1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28
|
module Network.Socket.Handle where
import qualified GHC.IO.Device (IODeviceType (Stream))
import GHC.IO.Handle.FD (fdToHandle')
import System.IO (BufferMode (..), Handle, IOMode (..), hSetBuffering)
import Network.Socket.Types
-- | Turns a Socket into an 'Handle'. By default, the new handle is
-- unbuffered. Use 'System.IO.hSetBuffering' to change the buffering.
--
-- Note that since a 'Handle' is automatically closed by a finalizer
-- when it is no longer referenced, you should avoid doing any more
-- operations on the 'Socket' after calling 'socketToHandle'. To
-- close the 'Socket' after 'socketToHandle', call 'System.IO.hClose'
-- on the 'Handle'.
--
-- Caveat 'Handle' is not recommended for network programming in
-- Haskell, e.g. merely performing 'hClose' on a TCP socket won't
-- cooperate with peer's 'gracefulClose', i.e. proper shutdown
-- sequence with appropriate handshakes specified by the protocol.
socketToHandle :: Socket -> IOMode -> IO Handle
socketToHandle s mode = invalidateSocket s err $ \oldfd -> do
h <- fdToHandle' oldfd (Just GHC.IO.Device.Stream) True (show s) mode True {-bin-}
hSetBuffering h NoBuffering
return h
where
err _ = ioError $ userError $ "socketToHandle: socket is no longer valid"
|