diff --git a/rel/files/emqttd_ctl b/rel/files/emqttd_ctl
index 8a65bd6d3..4292b893e 100755
--- a/rel/files/emqttd_ctl
+++ b/rel/files/emqttd_ctl
@@ -1,4 +1,6 @@
 #!/bin/sh
+# -*- tab-width:4;indent-tabs-mode:nil -*-
+# ex: ts=4 sw=4 et
 
 # /bin/sh on Solaris is not a POSIX compatible shell, but /usr/bin/ksh is.
 if [ `uname -s` = 'SunOS' -a "${POSIX_SHELL}" != "true" ]; then