PHPMailer\PHPMailer\POP3::sendString PHP Method

    protected function sendString($string)
    {
        if ($this->pop_conn) {
            if ($this->do_debug >= 2) {
                //Show client messages when debug >= 2
                echo "Client -> Server: {$string}";
            }
            return fwrite($this->pop_conn, $string, strlen($string));
        }
        return 0;
    }