Hi Matt,
This is very nice indeed! :-)
I got a small client working, but I found the unpacking of values in the
message callback function a bit cumbersome. I now have:
(define (pointer->struct-mosquitto_message pointer)
(let* ((size (ctype-size struct-mosquitto_message))
(bvec (pointer->bytevector pointer size)))
(Xcdata-ref bvec 0 struct-mosquitto_message))) ;The only way I
found that worked! :)
(define (receive-message mosq obj message)
(let* ((message (pointer->struct-mosquitto_message message))
(payload (cdata-ref message 'payload))
(size (cdata-ref message 'payloadlen))
(payload (pointer->string payload size)))
(display payload)
(newline)))
Is there some more convenient/right way to do that?
Best regards,
Mikael
On Thu, Oct 31, 2024 at 1:02 PM Matt Wette <[email protected]> wrote:
> On 10/31/24 1:48 AM, Ricardo G. Herdt wrote:
> > Hi,
> >
> > never did it myself, but you can create some bindings to libmosquitto
> > for your usecase. There are bindings for chicken, one can take some
> > inspiration from there: http://wiki.call-cc.org/eggref/5/mosquitto#api
> >
> > Regards,
> >
> > Ricardo
> >
> > Am 31.10.2024 03:24 schrieb Alan Wedel:
> >> I have been working on a controller that uses a microcontroller to
> >> read some sensors and publish their data to a mqtt broker. I would
> >> like to have a guile program subscribe to the mqtt broker and log the
> >> sensor readings to a file. Is there anyone using guile with mqtt like
> >> this? If so, how are you doing it?
> >
>
> Here is a dot-ffi file for mosquitto using nyacc:
>
> (define-ffi-module (ffi mosquitto)
> #:pkg-config "libmosquitto"
> #:include '("mosquitto.h"))
>
>
> I just uploaded nyacc-2.01.2, needed to compile above.
>
> refs:
> https://savannah.nongnu.org/projects/nyacc
> https://www.nongnu.org/nyacc/nyacc-fh-ug.html
>
> Matt
>
>
>
>
>
>
