Index: src_plugins/export_png/png.c
===================================================================
--- src_plugins/export_png/png.c	(revision 27875)
+++ src_plugins/export_png/png.c	(revision 27876)
@@ -759,7 +759,8 @@
 		pcb_hid_restore_layer_ons(save_ons);
 
 	png_foot();
-	fclose(f);
+	if (f != NULL)
+		fclose(f);
 
 	if (master_im != NULL) {
 		gdImageDestroy(master_im);