glx: add a line of Emacs helping variables
diff --git a/src/glx/x11/glxcmds.c b/src/glx/x11/glxcmds.c
index cac39a5..72ab489 100644
--- a/src/glx/x11/glxcmds.c
+++ b/src/glx/x11/glxcmds.c
@@ -1,3 +1,4 @@
+/* -*- mode: c; tab-width: 3; indent-tabs-mode: nil; c-basic-offset: 3; coding: utf-8-unix -*- */
 /*
  * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008)
  * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved.