diff --git a/test/input.output/file.streams/fstreams/filebuf.virtuals/underflow_utf8.dat b/test/input.output/file.streams/fstreams/filebuf.virtuals/underflow_utf8.dat
index 01ad2f9a..ee7063e1 100644
--- a/test/input.output/file.streams/fstreams/filebuf.virtuals/underflow_utf8.dat
+++ b/test/input.output/file.streams/fstreams/filebuf.virtuals/underflow_utf8.dat
@@ -1 +1 @@
-   
\ No newline at end of file
+乑乒乓
\ No newline at end of file