diff --git a/extras/libmemif/src/libmemif.h b/extras/libmemif/src/libmemif.h
index da48edd..3fc0648 100644
--- a/extras/libmemif/src/libmemif.h
+++ b/extras/libmemif/src/libmemif.h
@@ -73,6 +73,7 @@
   MEMIF_ERR_DISCONNECTED,	/*!< peer interface disconnected */
   MEMIF_ERR_UNKNOWN_MSG,	/*!< unknown message type */
   MEMIF_ERR_POLL_CANCEL,	/*!< memif_poll_event() was cancelled */
+  MEMIF_ERR_MAX_RING,		/*!< too large ring size */
 } memif_err_t;
 
 /**