_ (DEST_UNREACH_SENT, "destination unreachable response sent") \
_ (PACKET_TOO_BIG_SENT, "packet too big response sent") \
_ (TTL_EXPIRE_SENT, "hop limit exceeded response sent") \
_ (DEST_UNREACH_SENT, "destination unreachable response sent") \
_ (PACKET_TOO_BIG_SENT, "packet too big response sent") \
_ (TTL_EXPIRE_SENT, "hop limit exceeded response sent") \