非套接字上的套接字操作，zmq 选项

Question

每当我尝试在 zmq 中设置套接字选项时，我都会得到 Socket operation on non-socket。

zmq::socket_t socket = new zmq::socket_t(*context,ZMQ_REP);
int64_t t = 1000;
socket->setsockopt(ZMQ_RCVTIMEO,&t,sizeof(t));
socket->bind("ipc:///tmp/zmqsocket");

谁能告诉我我做错了什么？

我正在使用带有 c++ 绑定的 ZeroMQ 4.0.4。

编辑：尝试在绑定之前/之后设置选项，没有任何改变。

Answer 1

您应该为 ZMQ_RCVTIMEO 选项使用正确的类型，它使用 int（不是 int64）。

来自 zmq 文档zmq-setsockopt

ZMQ_RCVTIMEO: Maximum time before a recv operation returns with EAGAIN

Sets the timeout for receive operation on the socket. If the value is 0, zmq_recv(3) will return immediately, with a EAGAIN error if there is no message to receive. If the value is -1, it will block until a message is available. For all other values, it will wait for a message for that amount of time before returning with an EAGAIN error.
Option value type   int
Option value unit   milliseconds
Default value   -1 (infinite)
Applicable socket types     all

那么下面的代码就可以工作了：

zmq::context_t context(1);
zmq::socket_t socket(context,ZMQ_REP);
int t = 1000;
socket.bind("ipc:///tmp/zmqsocket");
socket.setsockopt(ZMQ_RCVTIMEO,&t,sizeof(t));

Answer 2

记住 API v2.1 以来的经验法则

就 v2.1 而言，setsockopt() 联机帮助页警告 说：

     int zmq_setsockopt ( void       *socket,
                          int         option_name,
                          const void *option_value,
                          size_t      option_len
                          );
     Caution: All options,
              with the exception of ZMQ_SUBSCRIBE,    ZMQ_UNSUBSCRIBE,
                                    ZMQ_LINGER,       ZMQ_ROUTER_MANDATORY,
                                    ZMQ_PROBE_ROUTER, ZMQ_XPUB_VERBOSE,
                                    ZMQ_REQ_CORRELATE,
                                and ZMQ_REQ_RELAXED,
              only take effect for subsequent socket bind/connects.
              ^^^^                 ^^^^^^^^^^

渴望与已发布的 ZeroMQ API 兼容的代码应调用 .setsockopt() 来设置 ZMQ_RCVTIMEO 之前 转到 .connect() / .bind() p>