Index: Plug.tmpasm
===================================================================
--- Plug.tmpasm	(revision 35234)
+++ Plug.tmpasm	(revision 35235)
@@ -6,6 +6,7 @@
 	$(PLUGDIR)/io_dsn/read.o
 	$(PLUGDIR)/io_dsn/write.o
 	$(PLUGDIR)/io_dsn/ses.o
+	$(PLUGDIR)/io_dsn/export.o
 @]
 
 switch /local/pcb/io_dsn/controls
Index: export.c
===================================================================
--- export.c	(nonexistent)
+++ export.c	(revision 35235)
@@ -0,0 +1,122 @@
+/*
+ *                            COPYRIGHT
+ *
+ *  pcb-rnd, interactive printed circuit board design
+ *
+ *  dsn IO plugin - file format write
+ *  pcb-rnd Copyright (C) 2021 Tibor 'Igor2' Palinkas
+ *  (Supported by NLnet NGI0 PET Fund in 2021)
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ *  Contact:
+ *    Project page: http://repo.hu/projects/pcb-rnd
+ *    lead developer: http://repo.hu/projects/pcb-rnd/contact.html
+ *    mailing list: pcb-rnd (at) list.repo.hu (send "subscribe")
+ */
+
+#include "config.h"
+#include <librnd/core/plugins.h>
+#include <librnd/core/hid_init.h>
+#include <librnd/core/hid_nogui.h>
+#include <librnd/core/hid_attrib.h>
+#include <librnd/core/safe_fs.h>
+
+#include "board.h"
+#include "hid_cam.h"
+#include "plug_io.h"
+
+#include "write.h"
+
+
+static const char *dsn_cookie = "dsn importer/ses";
+
+static rnd_hid_t dsn_hid;
+
+static const rnd_export_opt_t dsn_options[] = {
+	{"dsnfile", "SPECCTRA DSN file",
+	 RND_HATT_STRING, 0, 0, {0, 0, 0}, 0},
+#define HA_dsnfile 0
+};
+
+#define NUM_OPTIONS (sizeof(dsn_options)/sizeof(dsn_options[0]))
+
+static rnd_hid_attr_val_t dsn_values[NUM_OPTIONS];
+
+static const char *dsn_filename;
+
+static const rnd_export_opt_t *dsn_get_export_options(rnd_hid_t *hid, int *n)
+{
+	const char *val = dsn_values[HA_dsnfile].str;
+	if ((PCB != NULL) && ((val == NULL) || (*val == '\0')))
+		pcb_derive_default_filename(PCB->hidlib.filename, &dsn_values[HA_dsnfile], ".dsn");
+	if (n)
+		*n = NUM_OPTIONS;
+	return dsn_options;
+}
+
+static void dsn_do_export(rnd_hid_t *hid, rnd_hid_attr_val_t *options)
+{
+	FILE *f;
+
+	if (!options) {
+		dsn_get_export_options(hid, 0);
+		options = dsn_values;
+	}
+	dsn_filename = options[HA_dsnfile].str;
+	if (!dsn_filename)
+		dsn_filename = "pcb-rnd-out.dsn";
+
+	f = rnd_fopen(&PCB->hidlib, dsn_filename, "w");
+	if (f == NULL) {
+		rnd_message(RND_MSG_ERROR, "dsn export: can not open '%s' for write\n", dsn_filename);
+		return;
+	}
+	io_dsn_write_pcb(NULL, f, NULL, dsn_filename, 0);
+	fclose(f);
+}
+
+static int dsn_parse_arguments(rnd_hid_t *hid, int *argc, char ***argv)
+{
+	return rnd_hid_parse_command_line(argc, argv);
+}
+
+
+void pcb_dsn_export_uninit(void)
+{
+	rnd_export_remove_opts_by_cookie(dsn_cookie);
+	rnd_hid_remove_hid(&dsn_hid);
+}
+
+void pcb_dsn_export_init(void)
+{
+	memset(&dsn_hid, 0, sizeof(rnd_hid_t));
+	rnd_hid_nogui_init(&dsn_hid);
+
+	dsn_hid.struct_size = sizeof(rnd_hid_t);
+	dsn_hid.name = "dsn";
+	dsn_hid.description = "Exports DSN format";
+	dsn_hid.exporter = 1;
+	dsn_hid.get_export_options = dsn_get_export_options;
+	dsn_hid.do_export = dsn_do_export;
+	dsn_hid.parse_arguments = dsn_parse_arguments;
+	dsn_hid.argument_array = dsn_values;
+
+	rnd_hid_register_hid(&dsn_hid);
+	rnd_hid_load_defaults(&dsn_hid, dsn_options, NUM_OPTIONS);
+
+	rnd_export_register_opts2(&dsn_hid, dsn_options, sizeof(dsn_options) / sizeof(dsn_options[0]), dsn_cookie, 0);
+}
+
Index: io_dsn.c
===================================================================
--- io_dsn.c	(revision 35234)
+++ io_dsn.c	(revision 35235)
@@ -42,6 +42,8 @@
 
 void pcb_dsn_ses_uninit(void);
 void pcb_dsn_ses_init(void);
+void pcb_dsn_export_uninit(void);
+void pcb_dsn_export_init(void);
 
 
 static const char *dsn_cookie = "dsn IO";
@@ -67,6 +69,7 @@
 void pplg_uninit_io_dsn(void)
 {
 	pcb_dsn_ses_uninit();
+	pcb_dsn_export_uninit();
 	RND_HOOK_UNREGISTER(pcb_plug_io_t, pcb_plug_io_chain, &io_dsn);
 }
 
@@ -94,6 +97,7 @@
 	RND_HOOK_REGISTER(pcb_plug_io_t, pcb_plug_io_chain, &io_dsn);
 
 	pcb_dsn_ses_init();
+	pcb_dsn_export_init();
 
 	return 0;
 }