getArgs, -- :: IO [String]
getProgName, -- :: IO String
getEnv, -- :: String -> IO String
+#ifdef __GLASGOW_HASKELL__
withArgs,
withProgName,
+#endif
) where
import Prelude
-import System.IO ( bracket )
+#ifndef __NHC__
+import Control.Exception ( bracket )
+#endif
-#ifndef __HUGS__
+#ifdef __GLASGOW_HASKELL__
import Foreign
import Foreign.C
import Control.Monad
-#endif
-
-#ifdef __GLASGOW_HASKELL__
import GHC.IOBase
+#include "config.h"
#endif
#ifdef __HUGS__
import Hugs.System
#endif
+#ifdef __NHC__
+import System
+ ( getArgs
+ , getProgName
+ , getEnv
+ )
+#endif
+
-- ---------------------------------------------------------------------------
-- getArgs, getProgName, getEnv
--- Computation `getArgs' returns a list of the program's command
+-- | Computation 'getArgs' returns a list of the program's command
-- line arguments (not including the program name).
-#ifndef __HUGS__
+#ifdef __GLASGOW_HASKELL__
getArgs :: IO [String]
getArgs =
alloca $ \ p_argc ->
isPathSeparator _ = False
--- Computation `getEnv var' returns the value
--- of the environment variable {\em var}.
-
--- This computation may fail with
--- NoSuchThing: The environment variable does not exist.
+-- | Computation 'getEnv' @var@ returns the value
+-- of the environment variable @var@.
+--
+-- This computation may fail with:
+--
+-- * 'System.IO.Error.isDoesNotExistError' if the environment variable
+-- does not exist.
getEnv :: String -> IO String
getEnv name =
foreign import ccall unsafe "getenv"
c_getenv :: CString -> IO (Ptr CChar)
-#endif /* __HUGS__ */
{-|
@withArgs args act@ - while executing action @act@, have 'System.getArgs'
-return @args@.
+return @args@ (GHC only).
-}
+withArgs :: [String] -> IO a -> IO a
withArgs xs act = do
p <- System.Environment.getProgName
withArgv (p:xs) act
{-|
-@withProgName name act@ - while executing action @act@, have 'System.getProgName'return @name@.
+@withProgName name act@ - while executing action @act@,
+have 'System.getProgName' return @name@ (GHC only).
-}
+withProgName :: String -> IO a -> IO a
withProgName nm act = do
xs <- System.Environment.getArgs
withArgv (nm:xs) act
-- Worker routine which marshals and replaces an argv vector for
-- the duration of an action.
+withArgv :: [String] -> IO a -> IO a
withArgv new_args act = do
pName <- System.Environment.getProgName
existing_args <- System.Environment.getArgs
foreign import ccall unsafe "setProgArgv"
setArgsPrim :: Int -> Ptr CString -> IO ()
+#endif /* __GLASGOW_HASKELL__ */