Add optional netgroup.h include for NetBSD hosts.
diff --git a/access.c b/access.c
index 39a7752..f6d6e27 100644
--- a/access.c
+++ b/access.c
@@ -20,6 +20,9 @@
 
 #include "rsync.h"
 #include "ifuncs.h"
+#ifdef HAVE_NETGROUP_H
+#include <netgroup.h>
+#endif
 
 static int allow_forward_dns;