diff --git a/patches/gawk-3.1.8/posix/gawmisc.diff b/patches/gawk-3.1.8/posix/gawmisc.diff
index b6a5f22..a67e5ce 100755
--- a/patches/gawk-3.1.8/posix/gawmisc.diff
+++ b/patches/gawk-3.1.8/posix/gawmisc.diff
@@ -2,8 +2,10 @@
 --- gawk-3.1.8-patched/posix/gawkmisc.c  2017-06-08 23:54:41.644575800 +0200
 ***************
 *** 1,3 ****
---- 1,4 ----
+--- 1,6 ----
++ #ifdef __CYGWIN__
 + #include <io.h>
++ #endif
   /* gawkmisc.c --- miscellaneous gawk routines that are OS specific.
 
      Copyright (C) 1986, 1988, 1989, 1991 - 1998, 2001 - 2004 the Free Software Foundation, Inc.