A text file monitor would be an APM feature. What exactly do you mean? Do want to search the contents of a text file and alert based on the presence or absence of certain text? Or what?
Yes I would need to be able to search the file for given line(s) of text or the absence of text. I am trying to get Cirrus to alert on a process that stops running on out CISCO routers. The Cirrus job writes the output of the command script to a file. A logfile monitor could then look for key words and grab out text to send in an alert. But my cirrus need is just what is top on my list currently. There are far more uses.
You could use a script to do this in APM today.