Function mpi::ffi::OMPI_C_MPI_WIN_DUP_FN

pub unsafe extern fn OMPI_C_MPI_WIN_DUP_FN(window: MPI_Win,
                                           win_keyval: c_int,
                                           extra_state: *mut c_void,
                                           attribute_val_in: *mut c_void,
                                           attribute_val_out: *mut c_void,
                                           flag: *mut c_int)
                                           -> c_int