Echo server/client haskell

client.hs

module Main (main) where

import Control.Monad (forever, unless)
import qualified Data.ByteString.Char8 as C
import Network.Socket
import Network.Run.TCP (runTCPClient)
import Network.Socket.ByteString (recv, sendAll)
import System.IO (hFlush, stdout)

main :: IO ()
main =
  runTCPClient "127.0.0.1" "8686" $ \s -> forever $ do
    putStr "> "
    hFlush stdout
    line <- C.getLine
    sendAll s line
    msg <- recv s 1024
    C.putStrLn msg

server.hs

module Main (main) where

import Control.Monad (forever, unless)
import qualified Data.ByteString as S
import Network.Socket
import Network.Run.TCP (runTCPServer)
import Network.Socket.ByteString (recv, sendAll)

main :: IO ()
main =
  runTCPServer Nothing "8686" (forever . talk)
  where
    talk s = do
      msg <- recv s 1024
      unless (S.null msg) $
        sendAll s msg