| Re: [paho-dev] Simultaneous sub/pub-instances |
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Thanks for the answer. Yeah, now I see that the callback function pointers are added to a command handler rather that to the main handle, as I first believed. I’ll try out that first thing Monday morning. //Daniel From: paho-dev-bounces@xxxxxxxxxxx [mailto:paho-dev-bounces@xxxxxxxxxxx]
On Behalf Of Nicholas O'Leary Hi Daniel, a single instance of the client can act as both publisher and subscriber; you do not need to separate them. I haven't touched the c client for a while, so can't point you at anything more specific, but hopefully that will point you in the right direction. Nick On 15 Aug 2014 22:16, "Daniel Rasmussen" <Daniel.Rasmussen@xxxxxxxxx> wrote: Hi Paho team, Thank you for a great MQTT library! I’m using the
org.eclipse.paho.mqtt.c library. In a project connecting existing devices to the Internet, I want a service (on the Internet) to be able to receive messages from devices, but the device must
also be able to publish messages to the service. This means that the device needs to run both a publisher and a subscriber instance. I’ve tried with the async API, running the two instances in two separate threads (eCos). It first seem very well, connecting success and subscribing and I’m able
both send and receive message through a mosquito broker. But sadly I’ve found that the API isn’t thread safe. The socket.c module holds a list of sockets (think is called
s), but this list is static and not protected so the list may be updated from one instance/thread while one other is accessing it.- A race condition causing the a zero pointer to be accessed. Am I abusing the library by threading two instances in simultaneously or am I just doing it wrong? I guess I could transfer to the sync API, but I thought that
the async API will perform better yield-wise. Thanks in advance. //Daniel ______________________________________________________________________________
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