code: def version
        v_ptr = ::FFI::MemoryPointer.new(:pointer, 1)
        r_ptr = ::FFI::MemoryPointer.new(:pointer, 1)
  
        RPM::C.headerNVR(ptr, nil, v_ptr, r_ptr)
        v = v_ptr.read_pointer.read_string
        r = r_ptr.read_pointer.read_string
        v_ptr.free
        r_ptr.free
        Version.new(v, r, self[:epoch])
      end
docs: TODO: signature
   @return [Version] Version for this package