secretbox_encrypt example

if (!is_resource($ifp)) {
            throw new SodiumException('Could not open input file for reading');
        }

        /** @var resource $ofp */
        $ofp = fopen($outputFile, 'wb');
        if (!is_resource($ofp)) {
            fclose($ifp);
            throw new SodiumException('Could not open output file for writing');
        }

        $res = self::secretbox_encrypt($ifp, $ofp, $size, $nonce, $key);
        fclose($ifp);
        fclose($ofp);
        return $res;
    }
    /** * Seal a file (rather than a string). Uses less memory than * ParagonIE_Sodium_Compat::crypto_secretbox_open(), but produces * the same result. * * Warning: Does not protect against TOCTOU attacks. You should * just load the file into memory and use crypto_secretbox_open() if * you are worried about those. * * @param string $inputFile * @param string $outputFile * @param string $nonce * @param string $key * @return bool * @throws SodiumException * @throws TypeError */