added zlibWrapper - zstd wrapper for zlib
diff --git a/programs/util.h b/programs/util.h
index 7627341..d791a2c 100644
--- a/programs/util.h
+++ b/programs/util.h
@@ -281,7 +281,7 @@
         return 0;
     }
  
-    while (entry = readdir(dir)) {
+    while ((entry = readdir(dir)) != NULL) {
         if (strcmp (entry->d_name, "..") == 0 ||
             strcmp (entry->d_name, ".") == 0) continue;
         pathLength = snprintf(path, PATH_MAX, "%s/%s", dirName, entry->d_name);