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<h2 class="title" style="clear: both"><a id="rep_base_meth"></a>Base API Methods</h2>
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<p>Base API applications use the following
Berkeley DB methods.</p>
<div class="variablelist">
<dl>
<dt>
<span class="term">
<a href="../api_reference/C/reptransport.html" class="olink">DB_ENV->rep_set_transport()</a>
</span>
</dt>
<dd>
<p>
The <a href="../api_reference/C/reptransport.html" class="olink">DB_ENV->rep_set_transport()</a> method configures the replication system's
communications infrastructure.
</p>
</dd>
<dt>
<span class="term">
<a href="../api_reference/C/repstart.html" class="olink">DB_ENV->rep_start()</a>
</span>
</dt>
<dd>
<p>
The <a href="../api_reference/C/repstart.html" class="olink">DB_ENV->rep_start()</a> method configures (or reconfigures) an existing database
environment to be a replication master or client.
</p>
</dd>
<dt>
<span class="term">
<a href="../api_reference/C/repmessage.html" class="olink">DB_ENV->rep_process_message()</a>
</span>
</dt>
<dd>
<p>
The <a href="../api_reference/C/repmessage.html" class="olink">DB_ENV->rep_process_message()</a> method is used to process incoming messages
from other environments in the replication group. For clients,
it is responsible for accepting log records and updating the
local databases based on messages from the master. For both
the master and the clients, it is responsible for handling
administrative functions (for example, the protocol for dealing
with lost messages), and permitting new clients to join an
active replication group. This method should only be called
after the replication system's communications infrastructure
has been configured via <a href="../api_reference/C/reptransport.html" class="olink">DB_ENV->rep_set_transport()</a>.
</p>
</dd>
<dt>
<span class="term">
<a href="../api_reference/C/repelect.html" class="olink">DB_ENV->rep_elect()</a>
</span>
</dt>
<dd>
<p>
The <a href="../api_reference/C/repelect.html" class="olink">DB_ENV->rep_elect()</a> method causes the replication group to elect a
new master; it is called whenever contact with the master is
lost and the application wants the remaining sites to select a
new master.
</p>
</dd>
<dt>
<span class="term">
<a href="../api_reference/C/envevent_notify.html" class="olink">DB_ENV->set_event_notify()</a>
</span>
</dt>
<dd>
<p>
The <a href="../api_reference/C/envevent_notify.html" class="olink">DB_ENV->set_event_notify()</a> method is needed for applications to
discover important replication-related events, such as the
result of an election and appointment of a new master.
</p>
</dd>
<dt>
<span class="term">
<a href="../api_reference/C/reppriority.html" class="olink">DB_ENV->rep_set_priority()</a>
</span>
</dt>
<dd>
<p>
The <a href="../api_reference/C/reppriority.html" class="olink">DB_ENV->rep_set_priority()</a> method configures the local site's priority for
the purpose of elections.
</p>
</dd>
<dt>
<span class="term">
<a href="../api_reference/C/repset_timeout.html" class="olink">DB_ENV->rep_set_timeout()</a>
</span>
</dt>
<dd>
<p>
This method optionally configures various timeout values. Otherwise
default timeout values as specified in <a href="../api_reference/C/repset_timeout.html" class="olink">DB_ENV->rep_set_timeout()</a> are
used.
</p>
</dd>
<dt>
<span class="term">
<a href="../api_reference/C/repset_limit.html" class="olink">DB_ENV->rep_set_limit()</a>
</span>
</dt>
<dd>
<p>
The <a href="../api_reference/C/repset_limit.html" class="olink">DB_ENV->rep_set_limit()</a> method imposes an upper bound on the amount of
data that will be sent in response to a single call to
<a href="../api_reference/C/repmessage.html" class="olink">DB_ENV->rep_process_message()</a>. During client recovery, that is, when a replica
site is trying to synchronize with the master, clients may ask
the master for a large number of log records. If it is going
to harm an application for the master message loop to remain
busy for an extended period transmitting records to the
replica, then the application will want to use <a href="../api_reference/C/repset_limit.html" class="olink">DB_ENV->rep_set_limit()</a> to
limit the amount of data the master will send before
relinquishing control and accepting other messages.
</p>
</dd>
<dt>
<span class="term">
<a href="../api_reference/C/repset_request.html" class="olink">DB_ENV->rep_set_request()</a>
</span>
</dt>
<dd>
<p>
This method sets a threshold for the minimum and maximum time that
a client waits before requesting retransmission of a missing
message.
</p>
</dd>
</dl>
</div>
<p>In addition to the methods previously described, Base API applications
may also call the following methods, as needed:
<a href="../api_reference/C/repstat.html" class="olink">DB_ENV->rep_stat()</a>, <a href="../api_reference/C/repsync.html" class="olink">DB_ENV->rep_sync()</a> and <a href="../api_reference/C/repconfig.html" class="olink">DB_ENV->rep_set_config()</a>.</p>
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