template <typename T> int attr_delete(int keyval);
template <typename T> int attr_get(int keyval, void* attr_value, int* flag);
template <typename T> int attr_put(int keyval, void* attr_value);
template <typename T> int attr_delete(int keyval);
template <typename T> int attr_get(int keyval, void* attr_value, int* flag);
template <typename T> int attr_put(int keyval, void* attr_value);