$NetBSD: patch-libs_vfork_wscript,v 1.1 2016/06/20 08:17:43 kamil Exp $

There are problems with C++11 heavy code on NetBSD when building against
_POSIX_SOURCE and _XOPEN_SOURCE. Fix it by using _NETBSD_SOURCE.

--- libs/vfork/wscript.orig	2016-02-19 01:28:56.000000000 +0000
+++ libs/vfork/wscript
@@ -25,4 +25,5 @@ def build(bld):
     obj.defines = [
             '_POSIX_SOURCE',
             '_XOPEN_SOURCE=500',
+            '_NETBSD_SOURCE',
     ]