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<erlref>
  <header>
    <copyright>
      <year>2004</year><year>2016</year>
      <holder>Ericsson AB. All Rights Reserved.</holder>
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      Licensed under the Apache License, Version 2.0 (the "License");
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    <title>snmpa_notification_filter</title>
    <prepared></prepared>
    <responsible></responsible>
    <docno></docno>
    <approved></approved>
    <checked></checked>
    <date></date>
    <rev></rev>
    <file>snmpa_notification_filter.xml</file>
  </header>
  <module>snmpa_notification_filter</module>
  <modulesummary>Behaviour module for the SNMP agent notification filters.</modulesummary>
  <description>
    <p>This module defines the behaviour of the agent notification
      filters. A <c>snmpa_notification_filter</c> compliant module 
      must export the following functions: </p>
    <list type="bulleted">
      <item>
        <p>handle_notification/2</p>
      </item>
    </list>
    <p>The semantics of them and their exact signatures are explained
      below. </p>
    <p>The purpose of notification filters is to allow for modification
      and/or suppression of a notification.</p>
    <p>A misbehaving filter will be removed.</p>
  </description>
  <funcs>
    <func>
      <name>handle_notification(Notif, Data) -> Reply</name>
      <fsummary>Handle a notification</fsummary>
      <type>
        <v>Reply = send | {send, NewNotif} | dont_send</v>
        <v>Notif =  NewNotif = notification() | trap()</v>
        <v>Data  = term()</v>
      </type>
      <desc>
        <p>Handle a notification to be sent. The filter can either
          accept the notification as is, return <c>send</c>, modify
          the notification, return <c>{send, NewNotif}</c> or
          suppress the notification, return <c>dont_send</c>.</p>
        <p><c>Data</c> is supplied at filter registration time,
          see <seealso marker="snmpa#register_notification_filter">register_notification_filter</seealso>.
          </p>
      </desc>
    </func>
  </funcs>
  
</erlref>

