diff --git a/include/Makefile.am b/include/Makefile.am
index 4110360cbfa6d77514ffb73f82e7cabc3c67bbae..fa3636263be783043eb120a1eaf4f9994b9ab2ad 100644
--- a/include/Makefile.am
+++ b/include/Makefile.am
@@ -77,6 +77,7 @@ noinst_HEADERS = \
 	maestro/i_pool.h       \
 	maestro/i_mempool.h    \
 	maestro/i_khash.h      \
+	maestro/i_ketopt.h     \
 	maestro/i_hashing.h    \
 	maestro/i_misc.h
 
diff --git a/include/maestro/i_ketopt.h b/include/maestro/i_ketopt.h
index 166938b8311778941a0424916f59eed77a721f14..db8bae31e76c85e1aa0222ad040b1063a36aa694 100644
--- a/include/maestro/i_ketopt.h
+++ b/include/maestro/i_ketopt.h
@@ -1,10 +1,7 @@
-/* taken from https://github.com/attractivechaos/klib/blob/master/ketopt.h */
-
-/* This file is originally part of klib, which is licensed under the
- * X11/MIT licnense: */
-
+/* ketopt.h from https://github.com/attractivechaos/klib/blob/master/ketopt.h */
+/* This is version  cc7e69f, dated Wed Nov 18 17:27:49 CET 2020 */
 /* The MIT License
-   Copyright (c) 2008, 2009, 2011 by Attractive Chaos <attractor@live.co.uk>
+   Copyright (c) 2008, by Attractive Chaos <attractor@live.co.uk>
    Permission is hereby granted, free of charge, to any person obtaining
    a copy of this software and associated documentation files (the
    "Software"), to deal in the Software without restriction, including
@@ -23,9 +20,8 @@
    CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
    SOFTWARE.
 */
-   
-#ifndef I_KETOPT_H
-#define I_KETOPT_H
+#ifndef KETOPT_H
+#define KETOPT_H
 
 #include <string.h> /* for strchr() and strncmp() */