Watch a file for changes

I'd like to watch one specific file within a folder on a server (connected via AFP, but not always connected) and be made aware of when the file stops modifying for more than 10 minutes (or so).
I have a log file that writes to itself - when it finally finishes, it stops writing.
I'd like to be alerted when it's finished.
The filename is always the same.
The contents vary, but at the end, I DO have a consistent message that is output, that I could use to fall back on if modification time doesn't work.
Any suggestions?
Thanks
I have a log file that writes to itself - when it finally finishes, it stops writing.
I'd like to be alerted when it's finished.
The filename is always the same.
The contents vary, but at the end, I DO have a consistent message that is output, that I could use to fall back on if modification time doesn't work.
Any suggestions?
Thanks