Method on_connection_open

cpp/examples/simple_send.cpp:61–65

    }

    void on_connection_open(proton::connection& c) override {
        if (c.reconnected()) {
            sent = confirmed;   // Re-send unconfirmed messages after a reconnect
        }
    }

    void on_sendable(proton::sender &s) override {
        while (s.credit() && sent < total) {