int nl_sock_send(struct nl_sock *, const struct ofpbuf *, bool wait);
int nl_sock_sendv(struct nl_sock *sock, const struct iovec iov[], size_t n_iov,
bool wait);
int nl_sock_send(struct nl_sock *, const struct ofpbuf *, bool wait);
int nl_sock_sendv(struct nl_sock *sock, const struct iovec iov[], size_t n_iov,
bool wait);