diff --git a/libc/private/resolv_cache.h b/libc/private/resolv_cache.h
index 2a54453..1dcc53f 100644
--- a/libc/private/resolv_cache.h
+++ b/libc/private/resolv_cache.h
@@ -95,4 +95,10 @@
                    const void*           answer,
                    int                   answerlen );
 
+/* Notify the cache a request failed */
+extern void
+_resolv_cache_query_failed( struct resolv_cache* cache,
+                   const void* query,
+                   int         querylen);
+
 #endif /* _RESOLV_CACHE_H_ */