Hello, Suppose I have a C struct like typedef { int a; int *b; } Foo; typedef Foo *fooptr; and all worker functions which are all basically int foofun (fooptr , fooptr, fooptr) where the first one is a out argument and the other two are in arguments and the return value is (almost) irrelevant. Now before I can pass arguments I have to initialize them and this is done with void init(fooptr ) function and all values have to be cleared which is done with void clear(fooptr ). I tried to import this to haskell like this. data Foo = Foo type FFptr = ForeignPtr Foo and because I would like to have a nice interface without manually worrying about allocation and freeing up I tried something like this: foreign import ccall "&clear" clear :: FunPtr (Ptr Foo -> IO ()) foreign import ccall "init" init :: Ptr Foo -> IO () foreign import ccall "foofun" foofun_ :: Ptr Foo -> Ptr Foo -> Ptr Foo -> IO Int foofun :: FFptr -> FFptr -> FFptr foofun f1 f2 = unsafePerformIO f where f = withForeignPtr f1 (p1 -> withForeignPtr f2 (p2 -> do p3 <- malloc init p3 r <- foofun_ p3 p1 p2 newForeignPtr clear p3 Now should that work or do I have to do some more reading on ffi and if so, would anyone recommend some material because this is all I could come up with. PS: An example of a haskell binding like this would be even more useful, if anyone knows of such.