[project @ 2002-10-14 14:54:16 by simonmar]

[ghc-hetmet.git] / ghc / compiler / ghci / InteractiveUI.hs

diff --git a/ghc/compiler/ghci/InteractiveUI.hs b/ghc/compiler/ghci/InteractiveUI.hs
index 8660650..686e17b 100644 (file)
--- a/ghc/compiler/ghci/InteractiveUI.hs
+++ b/ghc/compiler/ghci/InteractiveUI.hs
@@ -1,6 +1,6 @@
 {-# OPTIONS -#include "Linker.h" -#include "SchedAPI.h" #-}
 -----------------------------------------------------------------------------
--- $Id: InteractiveUI.hs,v 1.134 2002/09/13 15:02:32 simonpj Exp $
+-- $Id: InteractiveUI.hs,v 1.135 2002/10/14 14:54:16 simonmar Exp $
 --
 -- GHC Interactive User Interface
 --
@@ -74,6 +74,8 @@ import Foreign                ( nullPtr )
 import Foreign.C.String        ( CString, peekCString, withCString )
 import Data.IORef      ( IORef, newIORef, readIORef, writeIORef )
 
+import GHC.Posix       ( setNonBlockingFD )
+
 -----------------------------------------------------------------------------
 
 ghciWelcomeMsg = "\ 
@@ -319,7 +321,10 @@ readlineLoop = do
    cmstate <- getCmState
    (mod,imports) <- io (cmGetContext cmstate)
    io yield
-   l <- io (readline (mkPrompt mod imports))
+   l <- io (readline (mkPrompt mod imports)
+               `finally` setNonBlockingFD 0)
+               -- readline sometimes puts stdin into blocking mode,
+               -- so we need to put it back for the IO library
    case l of
        Nothing -> return ()
        Just l  ->