Need a systemd unit example that checks /etc/fstab for modification and sends a text message

[Tony Rodriguez <unixpro1970@xxxxxxxxx>]

From my understanding, it is frowned by systemd developers to 
"automatically" reload systemd via "systemctl daemon-reload" when 
/etc/fstab is modified.  Guessing this is why such functionality hasn't 
already been incorporated into systemd.  However, I would like to send a 
simple text message. Instructing users to manually invoke "systemctl  
deamon-reload" after modifying /etc/fstab via dmesg command or inside 
/var/log/messages.

Unsure how to do so inside a systemd UNIT.  Will someone please provide 
an example how to do so?

Thanks