Sorry but al the documentation is in English, it make no sense to translate this.
see:
http://www.steves-internet-guide.com/mqtt-works/
Assume: 192.168.178.xx =MQTT-broker (service), xx can be 01, 02 or an other device with a MQTT broker
On 192.168.178.02 (and all the other system which have subscribe)
/usr/bin/mosquitto_sub.exe" -h 192.168.178.xx -t # -v -d
oder
/usr/bin/mosquitto_sub.exe" -h 192.168.178.xx -t test/topic -v -d
On 192.168.178.01
/usr/bin/mosquitto_pub -h 192.168.178.xx -t test/topic -m helloWorld -d
The 192.168.178.02 (and all the other system which have subscribe to that topic) will receive the message
helloWorld
Note: you don't publish to an certain client, only to the MQTT-broker.
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In Python:
Subscribe to a topic and will receive the payloads for that topic:
http://www.steves-internet-guide.com/su ... tt-client/
Publish a topic with payload:
http://www.steves-internet-guide.com/pu ... tt-client/
In C++:
Subscribe and publish:
https://stackoverflow.com/questions/317 ... qtt-client
https://github.com/eclipse/paho.mqtt.cpp