X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=GHC%2FHandle.hs;h=52bf8cde99e4de0877b07139144ee74ea924c067;hb=b674b3cdb447d2265dccc4e3c343c9625f464a33;hp=0e9b3be0a957ede3b356cbc61c4d17495525406e;hpb=956ef5fcd15bee4981eec3e666891b3f63c8b345;p=haskell-directory.git

diff --git a/GHC/Handle.hs b/GHC/Handle.hs
index 0e9b3be..52bf8cd 100644
--- a/GHC/Handle.hs
+++ b/GHC/Handle.hs
@@ -924,16 +924,21 @@ openFd fd mb_fd_type is_socket filepath mode binary = do
 				   "file is locked" Nothing)
 #endif
 	   mkFileHandle fd is_socket filepath ha_type binary
-	 -- Stream or RawDevice
-	Stream    -> mkIt ha_type
-	RawDevice -> mkIt ha_type
+
+	Stream
+	   -- only *Streams* can be DuplexHandles.  Other read/write
+	   -- Handles must share a buffer.
+	   | ReadWriteHandle <- ha_type -> 
+		mkDuplexHandle fd is_socket filepath binary
+	   | otherwise ->
+		mkFileHandle   fd is_socket filepath ha_type binary
+
+	RawDevice -> 
+		mkFileHandle fd is_socket filepath ha_type binary
+
 	_ ->
 	  ioException (IOError Nothing UnsupportedOperation "openFd"
 			           "unknown file type" Nothing) 
-     where
-      mkIt ht
-       | isReadWriteHandleType ht = mkDuplexHandle fd is_socket filepath binary
-       | otherwise                = mkFileHandle   fd is_socket filepath ht binary
 
 fdToHandle :: FD -> IO Handle
 fdToHandle fd = do