+
+/* Flags used between the client and server */
+#define NBD_FLAG_HAS_FLAGS (1 << 0) /* Flags are there */
+#define NBD_FLAG_READ_ONLY (1 << 1) /* Device is read-only */
+
+#define NBD_DEFAULT_PORT "10809" /* Port on which named exports are
+ * served */
+
+/* Options that the client can select to the server */
+#define NBD_OPT_EXPORT_NAME (1 << 0) /* Client wants to select a named export (is followed by length and name of export) */