{-# LANGUAGE OverloadedStrings #-} import Control.Applicative import Control.Monad import Data.Monoid import Data.String import System.IO import System.Exit import System.Environment import System.ZMQ4.Monadic import qualified Data.ByteString.UTF8 as SB main :: IO () main = do args <- getArgs when (length args /= 2) $ do hPutStrLn stderr "usage: prompt