Ridiculous amount of work for OpenBSD.
diff --git a/src/libthread/FreeBSD.c b/src/libthread/FreeBSD.c
index e6ce09b..33fd311 100644
--- a/src/libthread/FreeBSD.c
+++ b/src/libthread/FreeBSD.c
@@ -41,3 +41,9 @@
 	return 0;
 }
 
+void
+_pthreadinit(void)
+{
+	__isthreaded = 1;
+	signal(SIGUSR2, sigusr2handler);
+}