diff --git a/lib/libthr/thread/thr_suspend_np.c b/lib/libthr/thread/thr_suspend_np.c
index 7fa668ddfca..de957356c6e 100644
--- a/lib/libthr/thread/thr_suspend_np.c
+++ b/lib/libthr/thread/thr_suspend_np.c
@@ -43,7 +43,7 @@ int
 _pthread_suspend_np(pthread_t thread)
 {
 	/* XXXTHR */
-	return (-1);
+	return (ENOTSUP);
 }
 
 void