process main {
    getargs() args;
    value(args) args;

    num_different(args.length, "2") bad_args;
    If (bad_args) {
        println("bad arguments");
        exit("1");
    };

    args->get("0") addr_ip;
    args->get("1") addr_port;

    sys.connect({"tcp", {"ipv4", addr_ip, addr_port}}) socket;
    If (socket.is_error) {
        println("connection error!");
        exit("1");
    };

    println("connected");

    socket->write("This echo client is implemented in NCD!\n\n");

    backtrack_point() recv_point;

    socket->read() data;
    If (data.not_eof) {
        socket->write(data);
        recv_point->go();
    };

    println("server disconnected");

    exit("0");
}