Node-red has a very useful node for monitoring files as they are being written into.
It basically runs
tail -f on a specified file and based on a configurable expression for splitting the output (typically a newline) will emit an item for each of them to be processed further downstream.
This can be useful for automating services that have no direct integrations by monitoring their log files for example.
I tried duplicating this behavior by executing the tail command using an execute node but since the node will not terminate if you specify the follow parameter on tail (to keep the tail active) nothing is processed downstream.