Index: Python-3.1.2/Python/dup2.c
===================================================================
--- Python-3.1.2.orig/Python/dup2.c	2010-06-23 00:47:41.396000927 +0100
+++ Python-3.1.2/Python/dup2.c	2010-06-23 00:47:57.825182597 +0100
@@ -11,6 +11,7 @@
  * Return fd2 if all went well; return BADEXIT otherwise.
  */
 
+#include <unistd.h>
 #include <fcntl.h>
 
 #define BADEXIT -1