diff --git a/iscan-free/sanei/sanei_pio.c b/iscan-free/sanei/sanei_pio.c
index a2073be..a800e05 100644
--- a/sanei/sanei_pio.c
+++ b/sanei/sanei_pio.c
@@ -73,7 +73,7 @@
 #elif HAVE_SYS_HW_H
 # include <sys/hw.h>
 #elif defined(__i386__)  && defined (__GNUC__)
-
+#include <sys/types.h>
 static __inline__ void
 outb (u_char value, u_long port)
 {