$NetBSD: patch-ah,v 1.8 2009/08/21 09:29:28 kefren Exp $
--- mono/metadata/gc.c.orig	2009-08-17 17:16:08.000000000 +0300
+++ mono/metadata/gc.c	2009-08-17 17:16:30.000000000 +0300
@@ -31,7 +31,7 @@
  * has the header and functions, but they don't work at all): in other cases
  * we fall back to the io-layer slightly slower and signal-unsafe Event.
  */
-#ifdef __linux__
+#if defined __linux__ || defined __NetBSD__
 #define USE_POSIX_SEM 1
 #endif
 #endif
