A plain GET subscribes to the topic and prints all published messages. Doing a POST publishes the post data to the topic and exits.
Subscribe to the temperature in the home/bedroom
subject published by
example.com:
curl mqtt://example.com/home/bedroom/temp
Send the value 75
to the home/bedroom/dimmer
subject hosted by the
example.com server:
curl -d 75 mqtt://example.com/home/bedroom/dimmer
It outputs two bytes topic length (MSB | LSB), the topic followed by the payload.
Remaining limitations in curl's MQTT support as of September 2022:
- Only QoS level 0 is implemented for publish
- No way to set retain flag for publish
- No TLS (mqtts) support