gpointer hook_data);
+/**
+ * Function to register a hook function for a viewer be completely redrawn.
+ *
+ * @param tab viewer's tab
+ * @param hook hook function of the viewer.
+ * @param hook_data hook data associated with the hook function.
+ */
+
+void lttvwindow_register_redraw_notify(Tab *tab,
+ LttvHook hook, gpointer hook_data);
+
+/**
+ * Function to unregister a hook function for a viewer be completely redrawn.
+ *
+ * @param tab viewer's tab
+ * @param hook hook function of the viewer.
+ * @param hook_data hook data associated with the hook function.
+ */
+
+void lttvwindow_unregister_redraw_notify(Tab *tab,
+ LttvHook hook, gpointer hook_data);
+
+
+/**
+ * Function to register a hook function for a viewer to re-do the events
+ * requests for the needed interval.
+ *
+ * This action is typically done after a "stop".
+ *
+ * The typical hook will remove all current requests for the viewer
+ * and make requests for missing information.
+ *
+ * @param tab viewer's tab
+ * @param hook hook function of the viewer.
+ * @param hook_data hook data associated with the hook function.
+ */
+
+void lttvwindow_register_continue_notify(Tab *tab,
+ LttvHook hook, gpointer hook_data);
+
+
+/**
+ * Function to unregister a hook function for a viewer to re-do the events
+ * requests for the needed interval.
+ *
+ * @param tab viewer's tab
+ * @param hook hook function of the viewer.
+ * @param hook_data hook data associated with the hook function.
+ */
+
+void lttvwindow_unregister_continue_notify(Tab *tab,
+ LttvHook hook, gpointer hook_data);
+
+
/**
* Function to register a hook function for a viewer to set/update its
* filter.