gtk_toolbar_insert (GTK_TOOLBAR (toolbar), item,-1); item =gtk_tool_button_new(gtk_image_new_from_icon_name ("gtk-quit", GTK_ICON_SIZE_SMALL_TOOLBAR),NULL); gtk_tool_item_set_tooltip_markup (item,"This is a demo button with a 'quit' icon"); gtk_actionable_set_action_name (...