pfSense

<?php

class watchpath {

	function __construct($path, $interval) {

		$this->path = $path;

		$this->interval = $interval;

		$this->last = time();

	}

	function wait() {

		while(true) {

			sleep($this->interval);

			clearstatcache();

			if (FALSE == ($stat = stat($this->path))) {

				continue;

			}

			$ctime = $stat[10];

			if ($ctime <= $this->last) {

				continue;

			}

			$this->last = $ctime;

			break;

		}

	}

}	

function printfile($path)

{

	$lines = file($path);

	echo("\n*** " . $path . "@" . $ctime . " ***\n");

	foreach ($lines as $num => $line) {

		echo($line);

	}

}

$path = "/tmp/test.txt";

$seconds = 1;

printfile($path);

$watchdog = new watchpath($path, $seconds);

while(true) {

	$watchdog->wait();

	printfile($path);

}

?>