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module Aws.Network where
import Data.Maybe
import Control.Exception
import Network.BSD (getProtocolNumber)
import Network.Socket
import System.Timeout
-- Make a good guess if a host is reachable.
hostAvailable :: String -> IO Bool
hostAvailable h = do
sock <- getProtocolNumber "tcp" >>= socket AF_INET Stream
addr <- (addrAddress . head) `fmap` getAddrInfo (Just (defaultHints { addrFlags = [ AI_PASSIVE ] } )) (Just h) (Just "80")
case addr of
remote@(SockAddrInet _ _) -> do
v <- catch (timeout 100000 (connect sock remote) >>= return . isJust)
(\(_ :: SomeException) -> return False)
close sock
return v
_ -> return False
|
