[zeromq-dev] zmq_socket_monitor blocks port of REP/REQ TCP/IP in C

Pieter Hintjens ph at imatix.com
Sat Jan 18 08:20:43 CET 2014


You should not be using monitoring for this, as there are various
kinds of problem that won't show as disconnects. Instead, send
heartbeat messages when there's no other traffic, and use the lack of
traffic as a sign of trouble.

On Thu, Jan 16, 2014 at 4:59 PM, Björn Kuhlbrodt
<bjoern.kuhlbrodt at gpsolar.com> wrote:
> Hello
>
>
>
> I‘ trying to use zmq_socket_monitor to get notice when my TCP/IP socket is
> disconnected. I do not send much but the user would like to know when
> something goes offline asap.
>
> All works fine up to the point where I stop the socket and (maybe a while
> later) start a new one. Here’s what I got:
>
>
>
> Main thread:
>
> m_pZContext = zmq_ctx_new();
>
> Start comm. threads
>
> Stop comm.  Threads
>
> zmq_ctx_term (m_pZContext); //_always crashes!
>
>
>
>
>
> Comm threads (n):
>
> void* pZReceiveSocket = zmq_socket(m_pZContext, ZMQ_REP);
>
> int result = zmq_bind(pZReceiveSocket, connection);
>
> int rc = zmq_socket_monitor(pZReceiveSocket, monitor.c_str(),
> ZMQ_EVENT_ALL);
>
> Start monitor threads
>
> Do comm until stop signal
>
> Stop monitor threads
>
> int rc = zmq_unbind(pZReceiveSocket, connection);
>
> ASSERT(rc == 0);
>
> rc = zmq_close(pZReceiveSocket);
>
> ASSERT(rc == 0);
>
>
>
>
>
> Monitor threads (one per comm. Thread):
>
> rc = zmq_connect (m_MonitorSocket, monitor.c_str());
>
> handle events until stop signal
>
> rc = zmq_disconnect (m_MonitorSocket, monitor.c_str());
>
> ASSERT (rc == 0);
>
> int rc = zmq_close (m_MonitorSocket);
>
> ASSERT (rc == 0);
>
>
>
> All threads end gracefully, all sockets have a  low LINGER, but zmq_ctx_term
> always crashes deep in libzmq.
>
>
>
> If I don’t use zmq_ctx_term the next time I try to open I get address in
> use.
>
>
>
> Only way out: don’t use zmq_socket_monitor and all works fine. That’s too
> bad, tough as I’d really like to know asap when the connection is gone.
>
>
>
> Any Ideas? Need more Input?
>
>
>
> Best Regards
>
> Björn
>
>
>
>
>
>
>
>
>
>
>
>
>
> Dr. Björn Kuhlbrodt
>
> Senior Software Developer
>
> GP Inspect GmbH
>
>
>
> Tel: +49 89 750778 4729
>
> Fax: +49 89 750778 4710
>
> E-Mail: bjoern.kuhlbrodt at gpsolar.com
>
>
>
> GP Inspect GmbH | Hainbuchenring 9-11 | 82061 Neuried | Deutschland
>
> Geschäftsführer | Christian Probst, Dr. Eric Rüland, Enis Ersü, Martin
> Heinrich
>
> Amtsgericht München | HRB 173887
>
>
>
> A company of ISRA VISION Group
>
>
>
> ------------------------------------------------------------------------------------------------------
>
> This e-mail may contain material that is confidential, privileged and for
> the sole use of the intended recipient. Any review, reliance or
>
> distribution by others or forwarding without express permission is strictly
> prohibited. If you are not the intended recipient, please
>
> contact the sender and delete all copies. GP Inspect GmbH, ISRA VISION AG,
> its branches and subsidiaries herewith exclude
>
> any liability for third-party information recognizably contained in this
> email or its attachments. Third-party information does not
>
> necessarily reflect the opinion of GP Inspect GmbH or, ISRA VISION AG.
>
> ------------------------------------------------------------------------------------------------------
>
> WWW.GPSOLAR.COM
>
>
>
> WWW.ISRAVISION.COM
>
> ------------------------------------------------------------------------------------------------------
>
>
> _______________________________________________
> zeromq-dev mailing list
> zeromq-dev at lists.zeromq.org
> http://lists.zeromq.org/mailman/listinfo/zeromq-dev
>



More information about the zeromq-dev mailing list