SlightPHP\SMTP::StartTLS PHP 메소드

    public function StartTLS()
    {
        $this->error = null;
        # to avoid confusion
        if (!$this->connected()) {
            $this->error = array("error" => "Called StartTLS() without being connected");
            return false;
        }
        fputs($this->smtp_conn, "STARTTLS" . $extra . $this->CRLF);
        $rply = $this->get_lines();
        $code = substr($rply, 0, 3);
        if ($this->do_debug >= 2) {
            echo "SMTP -> FROM SERVER:" . $this->CRLF . $rply;
        }
        if ($code != 220) {
            $this->error = array("error" => "STARTTLS not accepted from server", "smtp_code" => $code, "smtp_msg" => substr($rply, 4));
            if ($this->do_debug >= 1) {
                echo "SMTP -> ERROR: " . $this->error["error"] . ": " . $rply . $this->CRLF;
            }
            return false;
        }
        //Begin encrypted connection
        if (!stream_socket_enable_crypto($this->smtp_conn, true, STREAM_CRYPTO_METHOD_TLS_CLIENT)) {
            return false;
        }
        return true;
    }