foo.hs

import           Data.Char (ord)
import           Data.Conduit ((.|))
import qualified Data.Conduit as C
import qualified Data.Conduit.Combinators as C
import qualified Data.ByteString.Char8 as B

main = C.runConduit
     $ C.stdin
    .| C.concatMap B.words
    .| C.concatMap transform
    .| C.unlinesAscii
    .| C.stdout
  where transform = map (B.pack . show . ord) . B.unpack

run

[mmyrseth@set:~]$ echo -n "foo\nbar\nbaz" | runghc foo.hs
102
111
111
92
110
98
97
114
92
110
98
97
122