if serverDebugLog {
		fmt.Printf("%s < %d %s\n", sessionID, code, message)
	}
}

func startFTPServer(args []string) {
	var (
		port          int
		publicIP      string
		portRange     string
		tlsPrivateKey string
		tlsPublicCert string
		forceTLS      bool
	)

	var err error
	for _, arg := range args {
		tokens := strings.SplitN(arg, "=", 2)
		if len(tokens) != 2 {