   error = NULL;   n = gtk_recent_manager_purge_items (manager, &error);   g_assert (error == NULL);    recent_data = g_slice_new0 (GtkRecentData);   recent_data->mime_type = (char *)"text/plain";   recent_data->app_name = (char *)"testrecentchooser";   recent_data->app_exec = (char *)"testrecentchooser %u";   