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6    <title>Release 4.6: Replication Events</title>
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36      <p>It is now guaranteed the <a href="../api_reference/C/envevent_notify.html#event_notify_DB_EVENT_REP_STARTUPDONE" class="olink">DB_EVENT_REP_STARTUPDONE</a> event will be
37presented to the application after the corresponding
38<a href="../api_reference/C/envevent_notify.html#event_notify_DB_EVENT_REP_NEWMASTER" class="olink">DB_EVENT_REP_NEWMASTER</a> event, even in the face of extreme
39thread-scheduling anomalies.  (In previous releases, if the thread
40processing the NEWMASTER message was starved, and STARTUPDONE occurred
41soon after, the order might have been reversed.)</p>
42      <p>In addition, the <a href="../api_reference/C/envevent_notify.html#event_notify_DB_EVENT_REP_NEWMASTER" class="olink">DB_EVENT_REP_NEWMASTER</a> event is now presented
43to all types of replication applications: users of either the
44Replication Framework or the Base Replication API.  In both cases, the
45<a href="../api_reference/C/envevent_notify.html#event_notify_DB_EVENT_REP_NEWMASTER" class="olink">DB_EVENT_REP_NEWMASTER</a> event always means that a site other than
46the local environment has become master.</p>
47      <p>The <span class="bold"><strong>envid</strong></span> parameter to <a href="../api_reference/C/repmessage.html" class="olink">DB_ENV-&gt;rep_process_message()</a> has been changed to
48be of type "int" rather than "int *", and the environment ID of a new
49master is presented to the application along with the
50<a href="../api_reference/C/envevent_notify.html#event_notify_DB_EVENT_REP_NEWMASTER" class="olink">DB_EVENT_REP_NEWMASTER</a> event.  Replication applications should
51be modified to use the <a href="../api_reference/C/envevent_notify.html#event_notify_DB_EVENT_REP_NEWMASTER" class="olink">DB_EVENT_REP_NEWMASTER</a> event to determine
52the ID of the new master.</p>
53      <p>The <span class="bold"><strong>envid</strong></span> parameter has been removed from the <a href="../api_reference/C/repelect.html" class="olink">DB_ENV-&gt;rep_elect()</a>
54method and a new event type has been added.  The
55<a href="../api_reference/C/envevent_notify.html#event_notify_DB_EVENT_REP_ELECTED" class="olink">DB_EVENT_REP_ELECTED</a> event is presented to the application at
56the site which wins an election.  In the Berkeley DB 4.6 release, the normal
57result of a successful election is either the
58<a href="../api_reference/C/envevent_notify.html#event_notify_DB_EVENT_REP_NEWMASTER" class="olink">DB_EVENT_REP_NEWMASTER</a> event (with the winner's environment ID),
59or the <a href="../api_reference/C/envevent_notify.html#event_notify_DB_EVENT_REP_ELECTED" class="olink">DB_EVENT_REP_ELECTED</a> event.  Only one of the two events
60will ever be delivered.</p>
61      <p>The DB_REP_NEWMASTER return code has been removed from the
62<a href="../api_reference/C/repmessage.html" class="olink">DB_ENV-&gt;rep_process_message()</a> method.  Replication applications should be modified to
63use the <a href="../api_reference/C/envevent_notify.html#event_notify_DB_EVENT_REP_NEWMASTER" class="olink">DB_EVENT_REP_NEWMASTER</a> and <a href="../api_reference/C/envevent_notify.html#event_notify_DB_EVENT_REP_ELECTED" class="olink">DB_EVENT_REP_ELECTED</a>
64events to determine the existence of a new master.</p>
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