fwatchd - A file watching daemon
fwatchd can be controlled using fwatchctl, which may instruct fwatchd to track files and perform some action based on inotify events on that file.
usermod -aG fwatch $USER
useradd -r -d / -c "File watching daemon" -s /usr/bin/nologin fwatch
systemctl enable fwatch
systemctl start fwatch
fwatchctl track /tmp/example
fwatchd --foreground
fwatchctl track /tmp/example --alias /usr/bin/echo --script /usr/bin/cat"
echo "test" >> /tmp/example
fwatchctl list