Index: trunk/src_plugins/export_bboard/bboard.c
===================================================================
--- trunk/src_plugins/export_bboard/bboard.c	(revision 21307)
+++ trunk/src_plugins/export_bboard/bboard.c	(revision 21308)
@@ -169,7 +169,7 @@
 
 static pcb_hid_attribute_t *bboard_get_export_options(int *n)
 {
-	if (PCB)
+	if ((PCB != NULL)  && (bboard_options[HA_bboardfile].default_val.str_value == NULL))
 		pcb_derive_default_filename(PCB->Filename, &bboard_options[HA_bboardfile], ".png");
 
 	bboard_options[HA_bgcolor].default_val.str_value = pcb_strdup("#FFFFFF");
Index: trunk/src_plugins/export_bom/bom.c
===================================================================
--- trunk/src_plugins/export_bom/bom.c	(revision 21307)
+++ trunk/src_plugins/export_bom/bom.c	(revision 21308)
@@ -66,7 +66,7 @@
 
 static pcb_hid_attribute_t *bom_get_export_options(int *n)
 {
-	if (PCB)
+	if ((PCB != NULL)  && (bom_options[HA_bomfile].default_val.str_value == NULL))
 		pcb_derive_default_filename(PCB->Filename, &bom_options[HA_bomfile], ".bom");
 
 	if (n)
Index: trunk/src_plugins/export_dsn/dsn.c
===================================================================
--- trunk/src_plugins/export_dsn/dsn.c	(revision 21307)
+++ trunk/src_plugins/export_dsn/dsn.c	(revision 21308)
@@ -108,9 +108,8 @@
 
 static pcb_hid_attribute_t *dsn_get_export_options(int *n)
 {
-	if (PCB) {
+	if ((PCB != NULL)  && (dsn_options[HA_dsnfile].default_val.str_value == NULL))
 		pcb_derive_default_filename(PCB->Filename, &dsn_options[HA_dsnfile], ".dsn");
-	}
 	if (n)
 		*n = NUM_OPTIONS;
 	return dsn_options;
Index: trunk/src_plugins/export_dxf/dxf.c
===================================================================
--- trunk/src_plugins/export_dxf/dxf.c	(revision 21307)
+++ trunk/src_plugins/export_dxf/dxf.c	(revision 21308)
@@ -205,7 +205,7 @@
 {
 	const char *suffix = ".dxf";
 
-	if (PCB)
+	if ((PCB != NULL)  && (dxf_attribute_list[HA_dxffile].default_val.str_value == NULL))
 		pcb_derive_default_filename(PCB->Filename, &dxf_attribute_list[HA_dxffile], suffix);
 
 	if (n)
Index: trunk/src_plugins/export_fidocadj/fidocadj.c
===================================================================
--- trunk/src_plugins/export_fidocadj/fidocadj.c	(revision 21307)
+++ trunk/src_plugins/export_fidocadj/fidocadj.c	(revision 21308)
@@ -89,7 +89,7 @@
 {
 	const char *suffix = ".fcd";
 
-	if (PCB)
+	if ((PCB != NULL)  && (fidocadj_attribute_list[HA_fidocadjfile].default_val.str_value == NULL))
 		pcb_derive_default_filename(PCB->Filename, &fidocadj_attribute_list[HA_fidocadjfile], suffix);
 
 	if (n)
Index: trunk/src_plugins/export_gcode/gcode.c
===================================================================
--- trunk/src_plugins/export_gcode/gcode.c	(revision 21307)
+++ trunk/src_plugins/export_gcode/gcode.c	(revision 21308)
@@ -247,9 +247,8 @@
 		last_unit_value = gcode_attribute_list[HA_unit].default_val.int_value;
 	}
 
-	if (PCB) {
+	if ((PCB != NULL)  && (gcode_attribute_list[HA_basename].default_val.str_value == NULL))
 		pcb_derive_default_filename(PCB->Filename, &gcode_attribute_list[HA_basename], ".gcode");
-	}
 	if (n) {
 		*n = NUM_OPTIONS;
 	}
Index: trunk/src_plugins/export_gerber/gerber.c
===================================================================
--- trunk/src_plugins/export_gerber/gerber.c	(revision 21307)
+++ trunk/src_plugins/export_gerber/gerber.c	(revision 21308)
@@ -365,7 +365,7 @@
 
 static pcb_hid_attribute_t *gerber_get_export_options(int *n)
 {
-	if (PCB)
+	if ((PCB != NULL)  && (gerber_options[HA_gerberfile].default_val.str_value == NULL))
 		pcb_derive_default_filename(PCB->Filename, &gerber_options[HA_gerberfile], "");
 
 	if (n)
Index: trunk/src_plugins/export_ipcd356/ipcd356.c
===================================================================
--- trunk/src_plugins/export_ipcd356/ipcd356.c	(revision 21307)
+++ trunk/src_plugins/export_ipcd356/ipcd356.c	(revision 21308)
@@ -414,7 +414,7 @@
 
 static pcb_hid_attribute_t *ipcd356_get_export_options(int *n)
 {
-	if (PCB != NULL)
+	if ((PCB != NULL) && (ipcd356_options[HA_ipcd356_filename].default_val.str_value == NULL))
 		pcb_derive_default_filename(PCB->Filename, &ipcd356_options[HA_ipcd356_filename], ".net");
 
 	if (n != NULL)
Index: trunk/src_plugins/export_openems/export_openems.c
===================================================================
--- trunk/src_plugins/export_openems/export_openems.c	(revision 21307)
+++ trunk/src_plugins/export_openems/export_openems.c	(revision 21308)
@@ -168,7 +168,7 @@
 	const char *suffix = ".m";
 	pcb_mesh_t *mesh = pcb_mesg_get(MESH_NAME);
 
-	if (PCB)
+	if ((PCB != NULL)  && (openems_attribute_list[HA_openemsfile].default_val.str_value == NULL))
 		pcb_derive_default_filename(PCB->Filename, &openems_attribute_list[HA_openemsfile], suffix);
 
 	if (mesh != NULL) {
Index: trunk/src_plugins/export_openscad/export_openscad.c
===================================================================
--- trunk/src_plugins/export_openscad/export_openscad.c	(revision 21307)
+++ trunk/src_plugins/export_openscad/export_openscad.c	(revision 21308)
@@ -132,7 +132,7 @@
 {
 	const char *suffix = ".scad";
 
-	if (PCB)
+	if ((PCB != NULL)  && (openscad_attribute_list[HA_openscadfile].default_val.str_value == NULL))
 		pcb_derive_default_filename(PCB->Filename, &openscad_attribute_list[HA_openscadfile], suffix);
 
 	if (n)
Index: trunk/src_plugins/export_png/png.c
===================================================================
--- trunk/src_plugins/export_png/png.c	(revision 21307)
+++ trunk/src_plugins/export_png/png.c	(revision 21308)
@@ -490,7 +490,7 @@
 {
 	const char *suffix = get_file_suffix();
 
-	if (PCB)
+	if ((PCB != NULL)  && (png_attribute_list[HA_pngfile].default_val.str_value == NULL))
 		pcb_derive_default_filename(PCB->Filename, &png_attribute_list[HA_pngfile], suffix);
 
 	if (n)
Index: trunk/src_plugins/export_ps/eps.c
===================================================================
--- trunk/src_plugins/export_ps/eps.c	(revision 21307)
+++ trunk/src_plugins/export_ps/eps.c	(revision 21308)
@@ -148,7 +148,7 @@
 
 static pcb_hid_attribute_t *eps_get_export_options(int *n)
 {
-	if (PCB)
+	if ((PCB != NULL)  && (eps_attribute_list[HA_psfile].default_val.str_value == NULL))
 		pcb_derive_default_filename(PCB->Filename, &eps_attribute_list[HA_psfile], ".eps");
 
 	if (n)
Index: trunk/src_plugins/export_ps/ps.c
===================================================================
--- trunk/src_plugins/export_ps/ps.c	(revision 21307)
+++ trunk/src_plugins/export_ps/ps.c	(revision 21308)
@@ -438,7 +438,7 @@
 
 static pcb_hid_attribute_t *ps_get_export_options(int *n)
 {
-	if (PCB)
+	if ((PCB != NULL) && (ps_attribute_list[HA_psfile].default_val.str_value == NULL))
 		pcb_derive_default_filename(PCB->Filename, &ps_attribute_list[HA_psfile], ".ps");
 
 	if (n)
Index: trunk/src_plugins/export_stat/stat.c
===================================================================
--- trunk/src_plugins/export_stat/stat.c	(revision 21307)
+++ trunk/src_plugins/export_stat/stat.c	(revision 21308)
@@ -113,7 +113,7 @@
 {
 	const char *suffix = ".stat.lht";
 
-	if (PCB)
+	if ((PCB != NULL)  && (stat_attribute_list[HA_statfile].default_val.str_value == NULL))
 		pcb_derive_default_filename(PCB->Filename, &stat_attribute_list[HA_statfile], suffix);
 
 	if (n)
Index: trunk/src_plugins/export_svg/svg.c
===================================================================
--- trunk/src_plugins/export_svg/svg.c	(revision 21307)
+++ trunk/src_plugins/export_svg/svg.c	(revision 21308)
@@ -199,7 +199,7 @@
 {
 	const char *suffix = ".svg";
 
-	if (PCB)
+	if ((PCB != NULL)  && (svg_attribute_list[HA_svgfile].default_val.str_value == NULL))
 		pcb_derive_default_filename(PCB->Filename, &svg_attribute_list[HA_svgfile], suffix);
 
 	if (n)
Index: trunk/src_plugins/export_test/export_test.c
===================================================================
--- trunk/src_plugins/export_test/export_test.c	(revision 21307)
+++ trunk/src_plugins/export_test/export_test.c	(revision 21308)
@@ -43,9 +43,8 @@
 
 static pcb_hid_attribute_t *export_test_get_export_options(int *n)
 {
-	if (PCB) {
+	if ((PCB != NULL)  && (export_test_options[HA_export_testfile].default_val.str_value == NULL))
 		pcb_derive_default_filename(PCB->Filename, &export_test_options[HA_export_testfile], ".export_test");
-	}
 
 	if (n)
 		*n = NUM_OPTIONS;
Index: trunk/src_plugins/export_xy/xy.c
===================================================================
--- trunk/src_plugins/export_xy/xy.c	(revision 21307)
+++ trunk/src_plugins/export_xy/xy.c	(revision 21308)
@@ -141,7 +141,7 @@
 			xy_options[HA_unit].default_val.int_value = get_unit_struct("mil")->index;
 		last_unit_value = xy_options[HA_unit].default_val.int_value;
 	}
-	if (PCB)
+	if ((PCB != NULL)  && (xy_options[HA_xyfile].default_val.str_value == NULL))
 		pcb_derive_default_filename(PCB->Filename, &xy_options[HA_xyfile], ".xy");
 
 	if (n)