$NetBSD: patch-aj,v 1.2 2021/11/23 14:28:34 ryoon Exp $

--- libgphoto2_port/serial/unix.c.orig	2021-01-31 09:15:29.000000000 +0000
+++ libgphoto2_port/serial/unix.c
@@ -38,6 +38,9 @@
 
 #include <stdlib.h>
 #include <stdio.h>
+#ifdef __NetBSD__
+#define _NETBSD_SOURCE
+#endif
 #ifdef HAVE_FCNTL_H
 #include <fcntl.h>
 #endif