mosquitto_pub:tldr:99601

mosquitto_pub: Read newline delimited data from `stdin` as a message and publish it to `sensors/temperature` topic.

${echo

$ ${echo data-txt} | mosquitto_pub -t ${sensors-temperature} -l

try on your machine

This command is used to publish data to a topic in the MQTT broker using the mosquitto_pub utility. Let's break down the command:

${echo data-txt}: This is a placeholder indicating that the output of the command echo data-txt will be used as the message to be published. Basically, it means that the message to be sent will be "data-txt".
|: This is the pipe operator that takes the output of the preceding command and passes it as input to the next command.
mosquitto_pub: This is the mosquitto_pub utility, a command-line tool provided by the MQTT broker service Mosquitto. It is used for publishing MQTT messages.
-t ${sensors-temperature}: This specifies the topic to which the message should be published. ${sensors-temperature} is another placeholder indicating that the value of the topic will be provided at runtime. It means that the topic name will be determined by the variable "sensors-temperature".
-l: This option instructs mosquitto_pub to read the message from standard input. Since we piped the output of the echo command, the message to be published will be the output of echo data-txt.

In summary, this command sends the message "data-txt" to the MQTT broker, publishing it to a topic determined by the value of the variable "sensors-temperature".

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.

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