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QtMqtt module installation and linking problem

  • Hi,

    I try to install and compile qmqtt from its git repo. It was worked. But somehow now its giving below error.

    It is compiling but when I run :

    dyld: Library not loaded: @rpath/QtMqtt.framework/Versions/5/QtMqtt
      Referenced from: /Users/opop/Projects/build-qtmqtt-GCC_Release-Release/examples/mqtt/subscriptions/
      Reason: image not found
    The program has unexpectedly finished.

    What am I missing ? I am working at Mac os X sierra.

    Sometime Qtcreator look very complex after java world :=


  • Lifetime Qt Champion


    Where did you clone the repository from ? There are several non-official mqtt modules that exists.

  • I cloned :

    it gives same error. I am at Mac Os X sierra.

    In ubuntu(vmware) its working

    Do need to compile and install something ?

  • I solved with add library path to pro file as :

    LIBS +=-L/usr/local/Cellar/qt/5.10.0_1/lib

    One more question:

    Is the qtmqtt is a good way to send binary data ie: 80K images which captured by camera (object detection)?

  • Lifetime Qt Champion

    To what do you want to send these binary data ?

  • Lifetime Qt Champion

    mqtt was designed for IOT devices to easy broadcast ( publish ) data to other nodes.
    So it would not be my first choice for large heavy binary data but we send 100 MB xml across a lan connection and it was ok fast but not realtime at all.
    Also, the focus is on many to many connections via the broker so if you do not need say one node send an image, many nodes must see it. Then the mqtt protocol might not have much to offer you besides easy setup and operation.

  • @SGaist We are capturing objects and want to send them to remote noSQL (ie mongo) db with meta data info.

    According to our past experience we faced problems with mongo to write data from distance (connection lost , network error etc) so we used rabbitMQ, amqp . and mqtt. they are very reliable to send data.

    So we want to send pure png data to remote mqtt: such as:

    data: time, text, id , png(binary)


  • Lifetime Qt Champion

    I just built the module using the official pre-built package and tested an example of the module and it works fine.

    What branche did you build ?

  • I started over and compiled / installed now working just fine

    Can we use qmqt from another thread ?

  • Lifetime Qt Champion

    I haven't tested that but I don't currently see anything that would forbid it.

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