<?php
function is_site_down($site, $timeout = 10)
{
	if(!filter_var($site, FILTER_VALIDATE_URL))
	{
		return TRUE;
	}
	$curl = curl_init($site);
	curl_setopt($curl,CURLOPT_CONNECTTIMEOUT, $timeout);
	curl_setopt($curl,CURLOPT_HEADER, TRUE);
	curl_setopt($curl,CURLOPT_NOBODY, TRUE);
	curl_setopt($curl,CURLOPT_RETURNTRANSFER, TRUE);
	$response = curl_exec($curl);
	curl_close($curl);
	if ($response)
	{
		return FALSE;
	}
	return TRUE;
}

if (is_site_down('http://www.example.com'))
{
	echo 'Site is down, yo.';
}
else
{
	echo 'Site is up, bruh!';
}
?>