Left readFile001.out: openFile: resource busy (file is locked)
-- !!! readFile test

import System.IO
import System.IO.Error

source   = "readFile001.hs"
filename = "readFile001.out"

main = do
  s <- readFile source
  h <- openFile filename WriteMode
  hPutStrLn h s
  hClose h
  s <- readFile filename

  -- This open should fail, because the readFile hasn't been forced
  -- and the file is therefore still locked.
  tryIOError (openFile filename WriteMode) >>= print

  putStrLn s

  -- should be able to open it for writing now, because we've forced the
  -- whole file.
  h <- openFile filename WriteMode

  print h


{handle: readFile001.out}