fay-0.12.0.0: src/System/Process/Extra.hs

-- | Extra process functions.

module System.Process.Extra where

import System.Exit
import System.Process

-- | Read everything from a process, either failure or both stderr and stdout.
readAllFromProcess :: FilePath -> [String] -> String -> IO (Either String (String,String))
readAllFromProcess program flags input = do
  (code,out,err) <- readProcessWithExitCode program flags input
  return $ case code of
    ExitFailure 127 -> Left ("cannot find executable " ++ program)
    ExitFailure _   -> Left err
    ExitSuccess     -> Right (err, out)