Check proxy before cURL - php

Question

I need to check whether the selected $proxy is active or not and do a loop until a working one in proxy.txt is found before using it in a cURL. How could I do that? Below is a given proxy function.
<?php
function proxies()
{
$proxylist = file("proxy.txt");
$randomproxy = rand(0, sizeof($proxylist) - 1);
$proxylist = $proxylist[$randomproxy];
$words = explode(':', $proxylist);
return $words;
}
$proxy = proxies();
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, 'url');
curl_setopt($ch, CURLOPT_PROXYTYPE, CURLPROXY_SOCKS5_HOSTNAME);
curl_setopt($ch, CURLOPT_PROXY, $proxy[0]);
curl_setopt($ch, CURLOPT_PROXYPORT, $proxy[1]);
curl_setopt($ch, CURLOPT_PROXYUSERPWD, "$username:$password");
....
?>
Thank you.

Answer 1

maybe you can ping, something like this
function proxies()
{
return file("proxy.txt");
}
foreach ($proxies() as $proxy) {
$item = explode(':', $proxy);
$waitTimeoutInSeconds = 1;
if ($fp = fsockopen($item[0], $item[1], $errCode, $errStr, $waitTimeoutInSeconds)){
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, 'url');
curl_setopt($ch, CURLOPT_PROXYTYPE, CURLPROXY_SOCKS5_HOSTNAME);
curl_setopt($ch, CURLOPT_PROXY, $proxy[0]);
curl_setopt($ch, CURLOPT_PROXYPORT, $proxy[1]);
curl_setopt($ch, CURLOPT_PROXYUSERPWD, "$username:$password");
break;
}
}
fclose($fp);