Forrest logo
back to the mosquitto_pub tool

mosquitto_pub:tldr:19819

mosquitto_pub: Send the contents of a file (`data.txt`), by reading from `stdin` and send the entire input as a message and publish it to `sensors/temperature` topic.
$ mosquitto_pub -t ${sensors-temperature} -s < ${data-txt}
try on your machine

The given command is used to publish a message to a MQTT broker topic using the mosquitto_pub command-line utility. Here is a breakdown of the individual components:

  • mosquitto_pub: It is the command-line utility for publishing messages to an MQTT broker.
  • -t ${sensors-temperature}: This flag specifies the topic where the message will be published. ${sensors-temperature} likely refers to a variable or an environment variable containing the topic name. It will be replaced with the actual topic before executing the command.
  • -s: This flag tells mosquitto_pub to read the message payload from standard input.
  • < ${data-txt}: It redirects the content of the data.txt file as the message payload for publishing. ${data-txt} is another variable referring to a file name containing the message payload.

In summary, the command publishes the content of the data.txt file as a message payload to a topic named in ${sensors-temperature} using the mosquitto_pub utility.

This explanation was created by an AI. In most cases those are correct. But please always be careful and never run a command you are not sure if it is safe.
back to the mosquitto_pub tool