struct ofpbuf *ofperr_encode_reply(enum ofperr, const struct ofp_header *);
struct ofpbuf *ofperr_encode_hello(enum ofperr, const struct ofperr_domain *,
const char *);
struct ofpbuf *ofperr_encode_reply(enum ofperr, const struct ofp_header *);
struct ofpbuf *ofperr_encode_hello(enum ofperr, const struct ofperr_domain *,
const char *);