Multi Domain Checker

<?php
ob_start();
header("content-type: text/html; charset=utf-8");
/*
Çoklu Domain Sorgulama Scripti
Multi Domain Checker SCRIPT
Kodlayan Ahmet Burak DEMIRKOPARAN
### http://ahmtbrk.com ###
*/
set_time_limit(0);
?>
<form action="" method="post">
<textarea name="siteler" rows="20" cols="30"></textarea><br>
<input type="submit" value="Çoklu Sorgula">
</form>
<?php
if($_POST){
$sitelerial = $_POST["siteler"];
$siteler = explode("\n",$sitelerial);
foreach($siteler as $site){
$ch = curl_init();
curl_setopt($ch,CURLOPT_URL,"http://checkdomain.com/cgi-bin/checkdomain.pl?domain=".$site);
curl_setopt($ch,CURLOPT_USERAGENT,"Mozilla/5.0 (Windows NT 5.1; rv:10.0) Gecko/20100101 Firefox/10.0");
curl_setopt($ch,CURLOPT_REFERER,"http://checkdomain.com");
curl_setopt($ch,CURLOPT_FOLLOWLOCATION,TRUE);
curl_setopt($ch,CURLOPT_RETURNTRANSFER,true);
$kaynak = curl_exec($ch);
curl_close($ch);
if(strstr($kaynak,'has already been registered')==true){
    echo "<b>".$site."</b> -> <font color=red>Dolu</font><br>";
}else if(strstr($kaynak,'is still available')==true){
    echo "<b>".$site."</b> -> <font color=green>Boşta</font><br>";
}else{
    echo "<b>".$site."</b> -> invalid domain name<br>";
}
}
}
?>