function isSiteAvailible($url){

    // Check, if a valid url is provided

    if(!filter_var($url, FILTER_VALIDATE_URL)){

        return false;

    }

​

    // Initialize cURL

    $curlInit = curl_init($url);

    // Set options

    curl_setopt($curlInit,CURLOPT_CONNECTTIMEOUT,10);

    curl_setopt($curlInit,CURLOPT_HEADER,true);

    curl_setopt($curlInit,CURLOPT_NOBODY,true);

    curl_setopt($curlInit,CURLOPT_RETURNTRANSFER,true);

​

    // Get response

    $response = curl_exec($curlInit);

    // Close a cURL session

    curl_close($curlInit);

​

    return $response?true:false;

}