.. index:: single: monitoring
.. _monitoring/0:

.. rst-class:: right

**protocol**

``monitoring``
==============

Event handlers protocol. The handlers are automatically called by the runtime for messages sent using the ``::/2`` control construct from objects or categories compiled with the ``events`` flag set to ``allow``.

| **Availability:** 
|    ``built_in``

| **Author:** Paulo Moura
| **Version:** 1:2:0
| **Date:** 2018-11-29

| **Compilation flags:**
|    ``static, built_in``


| **Dependencies:**
|   (none)


| **Remarks:**
|    (none)

| **Inherited public predicates:**
|    (none)

.. contents::
   :local:
   :backlinks: top

Public predicates
-----------------

.. index:: before/3
.. _monitoring/0::before/3:

``before/3``
^^^^^^^^^^^^

Event handler for ``before`` events. A ``before`` event handler may prevent a method from being looked up or called by failing.

| **Compilation flags:**
|    ``static``

| **Template:**
|    ``before(Object,Message,Sender)``
| **Mode and number of proofs:**
|    ``before(?term,?term,?term)`` - ``zero_or_more``


------------

.. index:: after/3
.. _monitoring/0::after/3:

``after/3``
^^^^^^^^^^^

Event handler for ``after`` events. An ``after`` event handler may prevent a method from succeeding by failing.

| **Compilation flags:**
|    ``static``

| **Template:**
|    ``after(Object,Message,Sender)``
| **Mode and number of proofs:**
|    ``after(?term,?term,?term)`` - ``zero_or_more``


------------

Protected predicates
--------------------

(none)

Private predicates
------------------

(none)

Operators
---------

(none)

