From: Julian Ospald <hasufell@gentoo.org>
Date: Mon Jul 30 07:49:46 UTC 2012
Subject: gcc-4.7

https://bugs.gentoo.org/show_bug.cgi?id=428574

--- src/freedoko.cpp
+++ src/freedoko.cpp
@@ -37,6 +37,7 @@
 
 #include "constants.h"
 #include <time.h>
+#include <unistd.h>
 #ifdef WINDOWS
 // for 'mkdir'
 #include <io.h>