better WM_DELETE_WINDOW protocol handler in case of multiple windows

src/paste.c

@@ -338,7 +338,7 @@ void merge_file(int selection_load, const char ext[])
     if(selection_load==0)
     {
      if(!strcmp(ext,"")) {
-       my_snprintf(tmp, S(tmp), "load_file_dialog {Merge file} {.sch.sym} INITIALLOADDIR", ext);
+       my_snprintf(tmp, S(tmp), "load_file_dialog {Merge file} {.sch.sym} INITIALLOADDIR");
        tcleval(tmp);
        if(!strcmp(tclresult(),"")) return;
        my_strncpy(name, (char *)tclresult(), S(name));

src/xinit.c

@@ -1213,7 +1213,7 @@ static void destroy_window(int *window_count, const char *win_path)
   savectx = xctx;
   if(*window_count) {
     int close = 0;
-    dbg(1, "new_schematic() destroy {%s}\n", win_path);
+    dbg(0, "new_schematic() destroy {%s}\n", win_path);
     if(xctx->modified && has_x) {
       tcleval("tk_messageBox -type okcancel  -parent [xschem get topwindow] -message \""
               "[get_cell [xschem get schname] 0]"

src/xschem.tcl

@@ -4607,14 +4607,19 @@ proc build_widgets { {topwin {} } } {
   #wm maxsize . 1600 1200
   if { $rootwin == {.}} {
     wm protocol $rootwin WM_DELETE_WINDOW {
-      if { [xschem get current_win_path] eq {.drw} } {
-        xschem exit
-      } else {
-        xschem new_schematic destroy [xschem get current_win_path] {}
-      }
+       set old  [xschem get current_win_path]
+       save_ctx $old
+       restore_ctx .drw
+       housekeeping_ctx
+       xschem new_schematic switch_win .drw
+       xschem exit
+       # did not exit ... switch back 
+       restore_ctx $old
+       housekeeping_ctx
+       xschem new_schematic switch_win $old
     }
   } else {
-    wm protocol $topwin WM_DELETE_WINDOW "xschem new_schematic destroy $topwin.drw {}"
+    wm protocol $rootwin WM_DELETE_WINDOW "xschem new_schematic destroy $topwin.drw {}"
   }
 
   frame $topwin.statusbar