Making a ping command prompt in php

1

I am making a pinging script in php for a web server.


<html>
<head>
<title>Launch</title>
</head>
<body>
<form action='ping.php' method='post'>
ping address:<br>
<input type='text' name='address'><br><br>
Amount:<br>
<input type='text' name='amount'><br>
<br>
Packet Size (Max 65500):<br>
<input type='text' name='size'><br>
<input type='submit' name='submit' value='submit'><br>
</form>
</body>
</html>

<?php
//code for actual ping
if(isset($_POST['submit'])) 
//if submit has been pressed
{
 $address=$_POST['address'];
 $amount=$_POST['amount'];
 $size=$_POST['size'];
 //above is a security measure to make sure it pings the typed address
 exec("ping -n $amount -l $size -w 0 $address",$results);
 //the actual ping execution command
 //output thrown in $results
 $count=count($results);
 //counts number of rows $in results array
 for($i=0;$i<$count;$i++)
 {
   print "$results[$i]<br>";
 }
}
 //the loops print out all results of $results  //line by line ?>

The problem is that this will only print the results after all are sent. How do you make it act like command prompt and make it print one by one.

thanks!