Return the number of fields and size (not yet) of a compound type.

def inq_compound(self, name):
        """
        Return the number of fields and size (not yet) of a compound type.
        """
        name = create_string_buffer(name)
        self.library.inq_compound.argtypes = [c_char_p, POINTER(c_int)]
        self.library.inq_compound.restype = None
        nfields = c_int()
        self.library.inq_compound(name, byref(nfields))
        return nfields.value