diff --git a/System/PosixFile.hsc b/System/PosixFile.hsc
--- a/System/PosixFile.hsc
+++ b/System/PosixFile.hsc
@@ -36,10 +36,7 @@
     }
 
 foreign import ccall "open"
-    c_open :: CString -> Flag -> IO CInt
-
-foreign import ccall "open"
-    c_open_mode :: CString -> Flag -> CInt -> IO CInt
+    c_open :: CString -> Flag -> CInt -> IO CInt
 
 foreign import ccall "read"
     c_read :: FD -> Ptr Word8 -> CInt -> IO CInt
@@ -54,14 +51,14 @@
 
 openRead :: FilePath -> IO FD
 openRead fp = do
-    h <- withCString fp $ \str -> c_open str oRdonly
+    h <- withCString fp $ \str -> c_open str oRdonly 438 -- == octal 666
     if h < 0
         then throwErrno $ "Could not open file: " ++ fp
         else return $ FD h
 
 openWrite :: FilePath -> IO FD
 openWrite fp = do
-    h <- withCString fp $ \str -> c_open_mode str (oWronly .|. oCreat) 438 -- == octal 666
+    h <- withCString fp $ \str -> c_open str (oWronly .|. oCreat) 438 -- == octal 666
     if h < 0
         then throwErrno $ "Could not open file: " ++ fp
         else return $ FD h
diff --git a/conduit.cabal b/conduit.cabal
--- a/conduit.cabal
+++ b/conduit.cabal
@@ -1,5 +1,5 @@
 Name:                conduit
-Version:             1.0.5
+Version:             1.0.5.1
 Synopsis:            Streaming data processing library.
 Description:
     @conduit@ is a solution to the streaming data problem, allowing for production, transformation, and consumption of streams of data in constant memory. It is an alternative to lazy I\/O which guarantees deterministic resource handling, and fits in the same general solution space as @enumerator@\/@iteratee@ and @pipes@. For a tutorial, please visit <https://haskell.fpcomplete.com/user/snoyberg/library-documentation/conduit-overview>.