This DisplayString reports the last-modified timestamp of the file being scanned by the fscan agent. An admin compares it to the current time or to stime to detect whether the monitored file is still actively being written to, which matters for confirming that log-based alerting via the scanTable's pattern matches is actually watching live data. For example, an mtime that stops advancing while the scanmode indicates active monitoring would suggest the source application has stopped logging, not that activity has genuinely gone quiet.