-----------------------------------------------------------------------------
---
+-- |
-- Module : System.Environment
-- Copyright : (c) The University of Glasgow 2001
--- License : BSD-style (see the file libraries/core/LICENSE)
+-- License : BSD-style (see the file libraries/base/LICENSE)
--
-- Maintainer : libraries@haskell.org
-- Stability : provisional
-- Portability : portable
--
--- $Id: Environment.hs,v 1.4 2002/01/02 14:40:11 simonmar Exp $
---
-- Miscellaneous information about the system environment.
--
-----------------------------------------------------------------------------
module System.Environment
(
- , getArgs -- :: IO [String]
+ getArgs -- :: IO [String]
, getProgName -- :: IO String
, getEnv -- :: String -> IO String
) where
peekArray (p - 1) (advancePtr argv 1) >>= mapM peekCString
-foreign import "getProgArgv" unsafe
+foreign import ccall unsafe "getProgArgv"
getProgArgv :: Ptr CInt -> Ptr (Ptr CString) -> IO ()
--- Computation `getProgName' returns the name of the program
--- as it was invoked.
+{-|
+Computation 'getProgName' returns the name of the program as it was
+invoked.
+However, this is hard-to-impossible to implement on some non-Unix
+OSes, so instead, for maximum portability, we just return the leafname
+of the program as invoked. Even then there are some differences
+between platforms: on Windows, for example, a program invoked as foo
+is probably really @FOO.EXE@, and that is what 'getProgName' will return.
+-}
getProgName :: IO String
getProgName =
alloca $ \ p_argc ->
else ioException (IOError Nothing NoSuchThing "getEnv"
"no environment variable" (Just name))
-foreign import ccall "getenv" unsafe
+foreign import ccall unsafe "getenv"
c_getenv :: CString -> IO (Ptr CChar)