diff --git a/programs/cmd/builtins.c b/programs/cmd/builtins.c
index 4c95b43c72d..cb7dfefbe1a 100644
--- a/programs/cmd/builtins.c
+++ b/programs/cmd/builtins.c
@@ -436,6 +436,7 @@ void WCMD_choice (const WCHAR * args) {
 static BOOL WCMD_AppendEOF(WCHAR *filename)
 {
     HANDLE h;
+    DWORD bytes_written;
 
     char eof = '\x1a';
 
@@ -448,7 +449,7 @@ static BOOL WCMD_AppendEOF(WCHAR *filename)
       return FALSE;
     } else {
       SetFilePointer (h, 0, NULL, FILE_END);
-      if (!WriteFile(h, &eof, 1, NULL, NULL)) {
+      if (!WriteFile(h, &eof, 1, &bytes_written, NULL)) {
         WINE_ERR("Failed to append EOF to %s (%d)\n", wine_dbgstr_w(filename), GetLastError());
         CloseHandle(h);
         return FALSE;