diff --git a/src/include/options-generator.c b/src/include/options-generator.c
index 8f953343..8a4ad0b2 100644
--- a/src/include/options-generator.c
+++ b/src/include/options-generator.c
@@ -26,7 +26,9 @@
 #include <stdarg.h>
 #include <string.h>
 #include <ctype.h>
-#include <unistd.h>
+#if ! defined(_WIN32) || defined(__CYGWIN__)
+#  include <unistd.h>
+#endif
 #include <sys/stat.h>
 #include <errno.h>