Method do_send

net/kernel_socket.cpp:495–498

    uint32_t m_num_calls = 0;

    ssize_t do_send(int sockfd, const void* buf, size_t count, int flags, Timeout timeout) override {
        struct iovec iov{const_cast<void*>(buf), count};
        return do_sendmsg(sockfd, tmp_msg_hdr(&iov, 1), flags, timeout);
    }

    ssize_t do_sendmsg(int sockfd, const struct msghdr* message, int flags, Timeout timeout) override {
        ssize_t n = photon::net::sendmsg(sockfd, message, flags | ZEROCOPY_FLAG, timeout);