php实现ping

<?php
// created by joe lumbroso 
// see some other good php3 scripts 
// goto http://www.dtheatre.com/scripts
echo &#39;<font color=\&#39;red\&#39;><blink><b>Pinging</b></blink></font><br>&#39;; 
＄to_ping = &#39;dtheatre.com&#39;; 
＄count = 3; 
＄psize = 65; 
echo &#39; Please be patient, this can take a few moments...\n<br><br>&#39;; 
flush();
while (1) { 
?> 
<pre class="brush:php;toolbar:false"> 
<? 
exec(&#39;ping -c ＄count -s ＄psize ＄to_ping&#39;, ＄list); 
for (＄i=0;＄i < count(＄list);＄i ) { 
print ＄list[＄i].&#39;\n&#39;; 
} 
?>