Fix process004 following the error improvements

tests/process004.hs

 module Main where
 
+import System.IO.Error
 import System.Process
 
-main = do
+main :: IO ()
+main = do test1 `catchIOError` \e -> putStrLn ("Exc: " ++ show e)
+          test2 `catchIOError` \e -> putStrLn ("Exc: " ++ show e)
+
+test1 :: IO ()
+test1 = do
   (_, _, _, commhand) <-
       runInteractiveProcess "true" [] (Just "/no/such/dir") Nothing
   exitCode <- waitForProcess commhand
   print exitCode
 
+test2 :: IO ()
+test2 = do
   commhand <- runProcess "true" [] (Just "/no/such/dir") Nothing
                 Nothing Nothing Nothing
   exitCode <- waitForProcess commhand
   print exitCode
+

tests/process004.stdout

-ExitFailure 126
-ExitFailure 126
+Exc: true: runInteractiveProcess: runInteractiveProcess: chdir: does not exist (No such file or directory)
+Exc: true: runProcess: runInteractiveProcess: chdir: does not exist (No such file or directory)