I have a program that reads a multimeter (thermometer) and logs the data to a text (tab delimited) file. I am looking for some way to follow the trends in the log file in something close to real time. If I had Excel on this computer, it would be easy. I would "Import External Data -> From Text -> Text import wizard -> Tell Excel to refresh the table every minute -> Insert chart based on the data table". Without Excel, though, I don't see an easy way to get the same effect, and was wondering if anyone here is aware of something.

I thought about using LibreOffice Calc for this, but Calc's "import data" command only seems to work for html or xml type files.
I found some information that suggests that Notepad++ can continuously (every 3 s) update a text file that it has open. Notepad++ doesn't have any charting abilities, though.

It's probably a long shot, but I thought I would ask this community if anyone here has any ideas.