$OpenBSD: patch-src_plugin_h,v 1.2 2014/10/27 09:07:07 landry Exp $
https://github.com/collectd/collectd/pull/779
missing include for pthread_t type
--- src/plugin.h.orig	Mon Sep 22 17:24:30 2014
+++ src/plugin.h	Mon Sep 22 17:26:33 2014
@@ -22,6 +22,7 @@
  *   Sebastian Harl <sh at tokkee.org>
  **/
 
+#include <pthread.h>
 #include "collectd.h"
 #include "configfile.h"
 #include "meta_data.h"
