Multithread proxy checker

<?php
set_time_limit(0);
/***********************************************
* Multithreaded Proxy Checker
* Coded by Miyachung
* Janissaries.Org
* Miyachung@hotmail.com
------------------------------------------------
* Demonstration -> http://www.youtube.com/watch?v=4icPZHv3W9g
* Type list like IP:PORT in a file
***********************************************/

/*-----------------------------------------------------------------------*/
    echo "\n[+]Enter your proxy list: ";
    $proxy_list = fgets(STDIN);
    $proxy_list = str_replace("\r\n","",$proxy_list);
    $proxy_list = trim($proxy_list);

    echo "[+]Enter number of thread: ";
    $thread = fgets(STDIN);
    $thread = str_replace("\r\n","",$thread);
    $thread = trim($thread);
    echo "[+]Enter timeout sec: ";
    $timeout = fgets(STDIN);
    $timeout = str_replace("\r\n","",$timeout);
    $timeout = trim($timeout);
    echo "[+]Checking proxies\n";
    echo "-------------------------------------------------------\n";
    $open_file    =    file($proxy_list);
    $open_file  =    preg_replace("#\r\n#si","",$open_file);


    checker($open_file,$thread);
/*-----------------------------------------------------------------------*/
function checker($ips,$thread)
{
    global $timeout;

    $multi    = curl_multi_init();
    $ips    = array_chunk($ips,$thread);
    $total    = 0;
    $time1  = time();
        foreach($ips as $ip)
        {
            for($i=0;$i<=count($ip)-1;$i++)
            {
            $curl[$i] = curl_init();
            curl_setopt($curl[$i],CURLOPT_RETURNTRANSFER,1);
            curl_setopt($curl[$i],CURLOPT_URL,"http://www.google.com.tr");
            curl_setopt($curl[$i],CURLOPT_PROXY,$ip[$i]);
            curl_setopt($curl[$i],CURLOPT_TIMEOUT,$timeout);
            curl_multi_add_handle($multi,$curl[$i]);
            }

            do
            {
            curl_multi_exec($multi,$active);
            usleep(11);
            }while( $active > 0 );

            foreach($curl as $cid => $cend)
            {
                $con[$cid] = curl_multi_getcontent($cend);
                curl_multi_remove_handle($multi,$cend);
                if(preg_match('#calendar\?tab=wc#si',$con[$cid]))
                {
                    $total++;
                    echo "[~]Proxy works -> ".$ip[$cid]."\n";
                    save_file("works.txt",$ip[$cid]);
                }
            }
        }
    $time2 = time();
    echo "\n[+]Total working proxies: $total,checking completed\n";
    echo "[+]Elapsed time -> ".($time2-$time1)." seconds\n";
    echo "[+]Coded by miyachung || Janissaries.Org\n";
    echo "-------------------------------------------------------\n";
}

function save_file($file,$content)
{
    $open = fopen($file,'ab');
    fwrite($open,$content."\r\n");
    fclose($open);
}

?>