How to find out the C type signature corresponding to a Haskell function type in FFI?

Marcin 'Qrczak' Kowalczyk qrczak at
Wed Mar 8 18:20:00 EST 2006

"Brian Hulley" <brianh at> writes:

> I've got a Haskell module with the following ffi import:
> foreign import ccall duma_init :: Int -> IO Int
> However my problem is that I've got no idea what the type signature
> for the corresponding C function should be,

HsInt duma_init(HsInt arg);

Or use int on the C side and CInt on the Haskell side.

fromIntegral can be used for converting integers in Haskell.

   __("<         Marcin Kowalczyk
   \__/       qrczak at

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