[project @ 2001-05-31 10:03:35 by simonmar]

- don't put a TTY into RAW mode if the handle is an output-only handle (so
  if you set stdout to NoBuffering and leave stdin as it is, you don't
  lose TTY processing on stdin).

- some cleanups.

diff --git a/ghc/lib/std/PrelHandle.hsc b/ghc/lib/std/PrelHandle.hsc
index ce13119..0452fc1 100644 (file)
--- a/ghc/lib/std/PrelHandle.hsc
+++ b/ghc/lib/std/PrelHandle.hsc
@@ -4,7 +4,7 @@
 #undef DEBUG
 
 -- -----------------------------------------------------------------------------
--- $Id: PrelHandle.hsc,v 1.6 2001/05/30 16:39:22 sewardj Exp $
+-- $Id: PrelHandle.hsc,v 1.7 2001/05/31 10:03:35 simonmar Exp $
 --
 -- (c) The University of Glasgow, 1994-2001
 --
@@ -266,6 +266,12 @@ ioe_notSeekable = ioException
    (IOError Nothing IllegalOperation ""
        "handle is not seekable" Nothing)
 
+ioe_bufsiz :: Int -> IO a
+ioe_bufsiz n = ioException 
+   (IOError Nothing InvalidArgument "hSetBuffering"
+       ("illegal buffer size " ++ showsPrec 9 n []) Nothing)
+                               -- 9 => should be parens'ified.
+
 -- -----------------------------------------------------------------------------
 -- Handle Finalizers
 
@@ -864,22 +870,16 @@ hSetBuffering handle mode =
          -- for input terminals we need to put the terminal into
          -- cooked or raw mode depending on the type of buffering.
          is_tty <- fdIsTTY (haFD handle_)
-         when is_tty $
+         when (is_tty && isReadableHandleType (haType handle_)) $
                case mode of
                  NoBuffering -> setCooked (haFD handle_) False
                  _           -> setCooked (haFD handle_) True
-               
+
          -- throw away spare buffers, they might be the wrong size
          writeIORef (haBuffers handle_) BufferListNil
 
          return (handle_{ haBufferMode = mode })
 
-ioe_bufsiz n
-  = ioException (IOError Nothing InvalidArgument "hSetBuffering"
-                       ("illegal buffer size " ++ showsPrec 9 n [])
-                               -- 9 => should be parens'ified.
-                       Nothing)
-
 -- -----------------------------------------------------------------------------
 -- hFlush
 
@@ -1049,12 +1049,7 @@ hIsReadable handle =
     case haType handle_ of 
       ClosedHandle        -> ioe_closedHandle
       SemiClosedHandle            -> ioe_closedHandle
-      htype               -> return (isReadable htype)
-  where
-    isReadable ReadHandle         = True
-    isReadable (ReadSideHandle _) = True
-    isReadable ReadWriteHandle    = True
-    isReadable _                 = False
+      htype               -> return (isReadableHandleType htype)
 
 hIsWritable :: Handle -> IO Bool
 hIsWritable (DuplexHandle _ _) = return False
@@ -1063,12 +1058,7 @@ hIsWritable handle =
     case haType handle_ of 
       ClosedHandle        -> ioe_closedHandle
       SemiClosedHandle            -> ioe_closedHandle
-      htype               -> return (isWritable htype)
-  where
-    isWritable AppendHandle    = True
-    isWritable WriteHandle     = True
-    isWritable ReadWriteHandle = True
-    isWritable _              = False
+      htype               -> return (isWritableHandleType htype)
 
 -- Querying how a handle buffers its data:
 

diff --git a/ghc/lib/std/PrelIOBase.lhs b/ghc/lib/std/PrelIOBase.lhs
index 351f271..148ae00 100644 (file)
--- a/ghc/lib/std/PrelIOBase.lhs
+++ b/ghc/lib/std/PrelIOBase.lhs
@@ -1,5 +1,5 @@
 % ------------------------------------------------------------------------------
-% $Id: PrelIOBase.lhs,v 1.40 2001/05/22 19:25:49 qrczak Exp $
+% $Id: PrelIOBase.lhs,v 1.41 2001/05/31 10:03:35 simonmar Exp $
 % 
 % (c) The University of Glasgow, 1994-2001
 %
@@ -236,6 +236,16 @@ data HandleType
  | ReadWriteHandle
  | ReadSideHandle  !(MVar Handle__)    -- read side of a duplex handle
 
+isReadableHandleType ReadHandle         = True
+isReadableHandleType ReadWriteHandle    = True
+isReadableHandleType (ReadSideHandle _) = True
+isReadableHandleType _                 = False
+
+isWritableHandleType AppendHandle    = True
+isWritableHandleType WriteHandle     = True
+isWritableHandleType ReadWriteHandle = True
+isWritableHandleType _              = False
+
 -- File names are specified using @FilePath@, a OS-dependent
 -- string that (hopefully, I guess) maps to an accessible file/object.