[project @ 2005-04-25 13:25:08 by simonmar]

Only ftruncate() regular files.

diff --git a/GHC/Handle.hs b/GHC/Handle.hs
index f3008c4..49ab6dc 100644 (file)
--- a/GHC/Handle.hs
+++ b/GHC/Handle.hs
@@ -813,15 +813,21 @@ openFile' filepath mode binary =
              throwErrnoIfMinus1Retry "openFile"
                (c_open f (fromIntegral oflags) 0o666)
 
-    h <- openFd fd Nothing False filepath mode binary
+    fd_type <- fdType fd
+
+    h <- openFd fd (Just fd_type) False filepath mode binary
             `catchException` \e -> do c_close (fromIntegral fd); throw e
        -- NB. don't forget to close the FD if openFd fails, otherwise
        -- this FD leaks.
        -- ASSERT: if we just created the file, then openFd won't fail
        -- (so we don't need to worry about removing the newly created file
        --  in the event of an error).
+
 #ifndef mingw32_HOST_OS
-    if mode == WriteMode
+       -- we want to truncate() if this is an open in WriteMode, but only
+       -- if the target is a RegularFile.  ftruncate() fails on special files
+       -- like /dev/null.
+    if mode == WriteMode && fd_type == RegularFile
       then throwErrnoIf (/=0) "openFile" 
               (c_ftruncate (fromIntegral fd) 0)
       else return 0