1 files changed, 55 insertions, 0 deletions
diff --git a/libraries/base/System/Cmd.hsc b/libraries/base/System/Cmd.hsc
new file mode 100644
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+++ b/libraries/base/System/Cmd.hsc
@@ -0,0 +1,55 @@
+-----------------------------------------------------------------------------
+-- 
+-- Module      :  System.Cmd
+-- Copyright   :  (c) The University of Glasgow 2001
+-- License     :  BSD-style (see the file libraries/core/LICENSE)
+-- 
+-- Maintainer  :  libraries@haskell.org
+-- Stability   :  provisional
+-- Portability :  portable
+--
+-- $Id: Cmd.hsc,v 1.1 2001/06/28 14:15:04 simonmar Exp $
+--
+-- Executing a command.
+--
+-----------------------------------------------------------------------------
+
+module System.Cmd
+    ( system        -- :: String -> IO ExitCode
+    ) where
+
+import Prelude
+
+import System.Exit
+import Foreign.C
+
+#ifdef __GLASGOW_HASKELL__
+import GHC.IOBase
+#endif
+
+#include "HsCore.h"
+
+-- ---------------------------------------------------------------------------
+-- system
+
+-- Computation `system cmd' returns the exit code
+-- produced when the operating system processes the command `cmd'.
+
+-- This computation may fail with
+--   PermissionDenied 
+--	The process has insufficient privileges to perform the operation.
+--   ResourceExhausted
+--      Insufficient resources are available to perform the operation.  
+--   UnsupportedOperation
+--	The implementation does not support system calls.
+
+system :: String -> IO ExitCode
+system "" = ioException (IOError Nothing InvalidArgument "system" "null command" Nothing)
+system cmd =
+  withUnsafeCString cmd $ \s -> do
+    status <- throwErrnoIfMinus1 "system" (primSystem s)
+    case status of
+        0  -> return ExitSuccess
+        n  -> return (ExitFailure n)
+
+foreign import ccall "systemCmd" unsafe primSystem :: UnsafeCString -> IO Int