c2hsC->Haskell comes with a marshalling library, called C2HS, which needs
to be explicitly imported into Haskell binding modules. The library contains
functions that users might use explicitly, but also functions that
C->Haskell will generate for some classes of bindings. The library takes
the form of a single Haskell module, whose c2hs places in the same
directory as the generated binding whenever it is given the
--copy-library (or -l) option.
c2hs