add fuse_invalidate() to library API
diff --git a/include/fuse.h b/include/fuse.h
index 726b681..845e645 100644
--- a/include/fuse.h
+++ b/include/fuse.h
@@ -171,6 +171,16 @@
  */
 struct fuse *fuse_get(void);
 
+/**
+ * Invalidate cached data of a file.
+ *
+ * Useful if the 'kernel_cache' mount option is given, since in that
+ * case the cache is not invalidated on file open.
+ *
+ * @return 0 on success or -errno on failure
+ */
+int fuse_invalidate(struct fuse *f, const char *path);
+
 /* ----------------------------------------------------------- *
  * More detailed API                                           *
  * ----------------------------------------------------------- */