diff --git a/libc/stdio/vfscanf.cpp b/libc/stdio/vfscanf.cpp
index d05a3a6..dfd001d 100644
--- a/libc/stdio/vfscanf.cpp
+++ b/libc/stdio/vfscanf.cpp
@@ -102,7 +102,7 @@
   void* allocation = nullptr; // Allocated but unassigned result for %mc/%ms/%m[.
   size_t capacity = 0; // Number of char/wchar_t units allocated in `allocation`.
 
-  _SET_ORIENTATION(fp, -1);
+  _SET_ORIENTATION(fp, ORIENT_BYTES);
 
   nassigned = 0;
   nread = 0;