<?PHP

$filename = "main.txt";    
$fp = fopen($filename, "r");//open file in read mode   
$contents = fread($fp, filesize($filename));//read file
$filecounter =1;
$cnt=0;
$myfile = "file".$filecounter.".txt";
$fp = fopen($myfile, 'a');
$phonenumbers = explode(",",$contents);
//echo $phonenumbers;
//var_dump($contents);
//var_dump($phonenumbers);
foreach ($phonenumbers as $phonenumber){
    fwrite($fp,$phonenumber."\n");
    $cnt++;
    if($cnt >999){  
        $filecounter++;
        $myfile = "file".$filecounter.".txt";
        $fp = fopen($myfile, 'a');
        $cnt=0;
    }
}


echo "Done";
exit();

?>