[project @ 2002-09-02 11:20:50 by ross]
[packages/old-time.git] / System / Exit.hs
1 -----------------------------------------------------------------------------
2 -- |
3 -- Module : System.Exit
4 -- Copyright : (c) The University of Glasgow 2001
5 -- License : BSD-style (see the file libraries/base/LICENSE)
6 --
7 -- Maintainer : libraries@haskell.org
8 -- Stability : provisional
9 -- Portability : portable
10 --
11 -- Exiting the program.
12 --
13 -----------------------------------------------------------------------------
14
15 module System.Exit
16 (
17 ExitCode(ExitSuccess,ExitFailure)
18 , exitWith -- :: ExitCode -> IO a
19 , exitFailure -- :: IO a
20 ) where
21
22 import Prelude
23
24 #ifdef __GLASGOW_HASKELL__
25 import GHC.IOBase
26 #endif
27
28 #ifdef __HUGS__
29 import Hugs.System
30 #endif
31
32 -- ---------------------------------------------------------------------------
33 -- exitWith
34
35 -- `exitWith code' terminates the program, returning `code' to the
36 -- program's caller. Before it terminates, any open or semi-closed
37 -- handles are first closed.
38
39 #ifdef __GLASGOW_HASKELL__
40 exitWith :: ExitCode -> IO a
41 exitWith ExitSuccess = throw (ExitException ExitSuccess)
42 exitWith code@(ExitFailure n)
43 | n == 0 = ioException (IOError Nothing InvalidArgument "exitWith" "ExitFailure 0" Nothing)
44 | otherwise = throw (ExitException code)
45 #endif /* __GLASGOW_HASKELL__ */
46
47 exitFailure :: IO a
48 exitFailure = exitWith (ExitFailure 1)