public function convertToPOSIX($ezpLocale)
    {
        if (!isset($this->conversionMap[$ezpLocale])) {
            $this->logger->warning("Could not convert locale '$ezpLocale' to POSIX format. Please check your locale configuration in ezplatform.yml");

            return;
        }

        return $this->conversionMap[$ezpLocale];
    }