main :: IO ()
main = do
  args <- getArgs
  case args of
    ["-r", f] -> capture f True
    [f]       -> capture f False 
    _         -> do name <- getProgName
                    putStrLn $ "Usage: " ++ name ++ " [-r] "
                                         ++ "<dump.pcap>"
main :: IO ()
main = do
  args <- getArgs
  case args of
    ["-r", f] -> capture f True
    [f]       -> capture f False 
    _         -> do name <- getProgName
                    putStrLn $ "Usage: " ++ name ++ " [-r] "
                                         ++ "<dump.pcap>"
main = do
  args <- getArgs
  case args of
    ["-r", f] -> capture f True
    [f]       -> capture f False 
    _         -> do name <- getProgName
                    putStrLn $ "Usage: " ++ name ++ " [-r] "
                                         ++ "<dump.pcap>"