diff --git a/src/base/assets_manager.c b/src/base/assets_manager.c
index ed613c8a1..cf4ae9ce7 100644
--- a/src/base/assets_manager.c
+++ b/src/base/assets_manager.c
@@ -1,4 +1,4 @@
-/**
+/**
  * File:   assets_manager.h
  * Author: AWTK Develop Team
  * Brief:  asset manager
@@ -27,6 +27,9 @@
 #include "base/system_info.h"
 #include "base/assets_manager.h"
 
+#define ASSETS_DIR "assets"
+#define THEME_DEFAULT "default"
+
 static ret_t asset_info_unref(asset_info_t* info);
 
 static int asset_cache_cmp_type(const void* a, const void* b) {
@@ -128,9 +131,6 @@ static asset_info_t* load_asset(uint16_t type, uint16_t subtype, const char* pat
 }
 #endif /*WITH_SDL*/
 
-#define ASSETS_DIR "assets"
-#define THEME_DEFAULT "default"
-
 static ret_t build_path(assets_manager_t* am, char* path, uint32_t size, bool_t ratio_sensitive,
                         const char* subpath, const char* name, const char* extname) {
   const char* res_root = assets_manager_get_res_root(am);
diff --git a/src/tkc/ostream.c b/src/tkc/ostream.c
index a8a7cbf95..e6370b6df 100644
--- a/src/tkc/ostream.c
+++ b/src/tkc/ostream.c
@@ -1,4 +1,4 @@
-/**
+/**
  * File:   tk_ostream.h
  * Author: AWTK Develop Team
  * Brief:  output stream interface
@@ -83,5 +83,5 @@ ret_t tk_ostream_flush(tk_ostream_t* stream) {
 }
 
 ret_t tk_ostream_write_byte(tk_ostream_t* stream, uint8_t byte) {
-  return tk_ostream_write_len(stream, &byte, 1, 1000);
+  return tk_ostream_write_len(stream, &byte, 1, 1000) == 1 ? RET_OK : RET_FAIL;
 }