--- scan/sane/bb_ledm.c.orig	Tue Jun 26 07:48:50 2012
+++ scan/sane/bb_ledm.c	Tue Jun 26 07:49:17 2012
@@ -16,6 +16,7 @@
 # include <string.h>
 # include <fcntl.h>
 # include <math.h>
+# include <unistd.h> /* usleep(3) */
 # include "sane.h"
 # include "saneopts.h"
 # include "hpmud.h"