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
curl mqtt://
Send the value '75' to the "home/bedroom/dimmer" subject hosted by the server:
curl -d 75 mqtt://

What does curl deliver as a response to a subscribe

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
Last modified 11mo ago