Anyone know a utility that triggers an action ...?

"[email protected] [blat]" <[email protected]> 30 Nov 2017 02:58:06 +0000
Newsgroups gmane.mail.blat
Message-ID <[email protected]>
Need to monitor a folder and Run a batch file with blat once a file with certain name and/or extension is stored therein. 
 Any suggestions?