LDP_PORT
connecting_su.sin.sin_port = htons(LDP_PORT);
connecting_su.sin6.sin6_port = htons(LDP_PORT);
su.sin.sin_port = htons(LDP_PORT);
su.sin6.sin6_port = htons(LDP_PORT);
sa.sin_port = htons(LDP_PORT);
sadest.sin_port = htons(LDP_PORT);
sadest6.sin6_port = htons(LDP_PORT);