fix typo
diff --git a/include/thread.h b/include/thread.h
index aa405af..330f150 100644
--- a/include/thread.h
+++ b/include/thread.h
@@ -120,7 +120,7 @@
 #define	alt		chanalt
 #define	nbrecv	channbrecv
 #define	nbrecvp	channbrecvp
-#define	nvrecvul	channbrecvul
+#define	nbrecvul	channbrecvul
 #define	nbsend	channbsend
 #define	nbsendp	channbsendp
 #define	nbsendul	channbsendul