<?xml version="1.0" encoding="UTF-8" standalone="no"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> <title>DB_ENV->rep_process_message()</title> <link rel="stylesheet" href="apiReference.css" type="text/css" /> <meta name="generator" content="DocBook XSL Stylesheets V1.73.2" /> <link rel="start" href="index.html" title="Berkeley DB C API Reference" /> <link rel="up" href="rep.html" title="Chapter 10. Replication Methods" /> <link rel="prev" href="repget_timeout.html" title="DB_ENV->rep_get_timeout()" /> <link rel="next" href="repclockskew.html" title="DB_ENV->rep_set_clockskew()" /> </head> <body> <div class="navheader"> <table width="100%" summary="Navigation header"> <tr> <th colspan="3" align="center">DB_ENV->rep_process_message()</th> </tr> <tr> <td width="20%" align="left"><a accesskey="p" href="repget_timeout.html">Prev</a> </td> <th width="60%" align="center">Chapter 10. Replication Methods </th> <td width="20%" align="right"> <a accesskey="n" href="repclockskew.html">Next</a></td> </tr> </table> <hr /> </div> <div class="sect1" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h2 class="title" style="clear: both"><a id="repmessage"></a>DB_ENV->rep_process_message()</h2> </div> </div> </div> <pre class="programlisting">#include <db.h> int DB_ENV->rep_process_message(DB_ENV *env, DBT *control, DBT *rec, int envid, DB_LSN *ret_lsnp) </pre> <p> The <code class="methodname">DB_ENV->rep_process_message()</code> method processes an incoming replication message sent by a member of the replication group to the local database environment. </p> <p> The <code class="methodname">DB_ENV->rep_process_message()</code> method is not called by most replication applications. It should only be called by Base API applications implementing their own network transport layer, explicitly holding replication group elections and handling replication messages outside of the Replication Manager framework. </p> <p> For implementation reasons, all incoming replication messages must be processed using the same <a class="link" href="env.html" title="Chapter 5. The DB_ENV Handle">DB_ENV</a> handle. It is not required that a single thread of control process all messages, only that all threads of control processing messages use the same handle. </p> <p> Before calling this method, the enclosing database environment must already have been opened by calling the <a class="xref" href="envopen.html" title="DB_ENV->open()">DB_ENV->open()</a> method and must already have been configured to send replication messages by calling the <a class="xref" href="reptransport.html" title="DB_ENV->rep_set_transport()">DB_ENV->rep_set_transport()</a> method. </p> <p> The <code class="methodname">DB_ENV->rep_process_message()</code> method has additional return values: </p> <div class="itemizedlist"> <ul type="disc"> <li> <p><a id="repmsg_DB_REP_DUPMASTER"></a> <span class="bold"><strong>DB_REP_DUPMASTER</strong></span> </p> <p> The <code class="methodname">DB_ENV->rep_process_message()</code> method will return <code class="literal">DB_REP_DUPMASTER</code> if the replication group has more than one master. The application should reconfigure itself as a client by calling the <a class="xref" href="repstart.html" title="DB_ENV->rep_start()">DB_ENV->rep_start()</a> method, and then call for an election by calling <a class="xref" href="repelect.html" title="DB_ENV->rep_elect()">DB_ENV->rep_elect()</a>. </p> </li> <li> <p><a id="repmsg_DB_REP_HOLDELECTION"></a> <span class="bold"><strong>DB_REP_HOLDELECTION</strong></span> </p> <p> The <code class="methodname">DB_ENV->rep_process_message()</code> method will return <code class="literal">DB_REP_HOLDELECTION</code> if an election is needed. The application should call for an election by calling <a class="xref" href="repelect.html" title="DB_ENV->rep_elect()">DB_ENV->rep_elect()</a>. </p> </li> <li> <p><a id="repmsg_DB_REP_IGNORE"></a> <span class="bold"><strong>DB_REP_IGNORE</strong></span> </p> <p> The <code class="methodname">DB_ENV->rep_process_message()</code> method will return <code class="literal">DB_REP_IGNORE</code> if this message cannot be processed. This is an indication that this message is irrelevant to the current replication state (for example, an old message from a previous generation arrives and is processed late). </p> </li> <li> <p><a id="repmsg_DB_REP_ISPERM"></a> <span class="bold"><strong>DB_REP_ISPERM</strong></span> </p> <p> The <code class="methodname">DB_ENV->rep_process_message()</code> method will return <code class="literal">DB_REP_ISPERM</code> if processing this message results in the processing of records that are permanent. The maximum LSN of the permanent records stored is returned. </p> </li> <li> <p><a id="repmsg_DB_REP_JOIN_FAILURE"></a> <span class="bold"><strong>DB_REP_JOIN_FAILURE</strong></span> </p> <p> The <code class="methodname">DB_ENV->rep_process_message()</code> method will return <code class="literal">DB_REP_JOIN_FAILURE</code> if a new master has been chosen but the client is unable to synchronize with the new master (possibly because the client has been configured with the <a class="link" href="repconfig.html#config_DB_REP_CONF_NOAUTOINIT">DB_REP_CONF_NOAUTOINIT</a> flag to turn off automatic internal initialization). </p> </li> <li> <p><a id="repmsg_DB_REP_NEWSITE"></a> <span class="bold"><strong>DB_REP_NEWSITE</strong></span> </p> <p> The <code class="methodname">DB_ENV->rep_process_message()</code> method will return <code class="literal">DB_REP_NEWSITE</code> if the system received contact information from a new environment. The <span class="bold"><strong>rec</strong></span> parameter contains the opaque data specified in the <span class="bold"><strong>cdata</strong></span> parameter to the <a class="xref" href="repstart.html" title="DB_ENV->rep_start()">DB_ENV->rep_start()</a>. The application should take whatever action is needed to establish a communication channel with this new environment. </p> </li> <li> <p><a id="repmsg_DB_REP_NOTPERM"></a> <span class="bold"><strong>DB_REP_NOTPERM</strong></span> </p> <p> The <code class="methodname">DB_ENV->rep_process_message()</code> method will return <code class="literal">DB_REP_NOTPERM</code> if a message carrying a <a class="link" href="reptransport.html#transport_DB_REP_PERMANENT">DB_REP_PERMANENT</a> flag was processed successfully, but was not written to disk. The LSN of this record is returned. The application should take whatever action is deemed necessary to retain its recoverability characteristics. </p> </li> </ul> </div> <p> Unless otherwise specified, the <code class="methodname">DB_ENV->rep_process_message()</code> <span> <span> method returns a non-zero error value on failure and 0 on success. </span> </span> </p> <div class="sect2" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h3 class="title"><a id="id1697517"></a>Parameters</h3> </div> </div> </div> <div class="sect3" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h4 class="title"><a id="id1697852"></a>control</h4> </div> </div> </div> <p> The <span class="bold"><strong>control</strong></span> parameter should reference a copy of the <span class="bold"><strong>control</strong></span> parameter specified by Berkeley DB on the sending environment. See the <a class="xref" href="reptransport.html" title="DB_ENV->rep_set_transport()">DB_ENV->rep_set_transport()</a> method for more information. </p> </div> <div class="sect3" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h4 class="title"><a id="id1697937"></a>envid</h4> </div> </div> </div> <p> The <span class="bold"><strong>envid</strong></span> parameter should contain the local identifier that corresponds to the environment that sent the message to be processed (see <a href="../../programmer_reference/rep_id.html" class="olink">Replication environment IDs</a> for more information). </p> </div> <div class="sect3" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h4 class="title"><a id="id1697870"></a>rec</h4> </div> </div> </div> <p> The <span class="bold"><strong>rec</strong></span> parameter should reference a copy of the <span class="bold"><strong>rec</strong></span> parameter specified by Berkeley DB on the sending environment. See the <a class="xref" href="reptransport.html" title="DB_ENV->rep_set_transport()">DB_ENV->rep_set_transport()</a> method for more information. </p> </div> <div class="sect3" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h4 class="title"><a id="id1697681"></a>ret_lsnp</h4> </div> </div> </div> <p> If <code class="methodname">DB_ENV->rep_process_message()</code> method returns <code class="literal">DB_REP_NOTPERM</code> then the <span class="bold"><strong>ret_lsnp</strong></span> parameter will contain the log sequence number of this permanent log message that could not be written to disk. If <code class="methodname">DB_ENV->rep_process_message()</code> method returns <code class="literal">DB_REP_ISPERM</code> then the <span class="bold"><strong>ret_lsnp</strong></span> parameter will contain largest log sequence number of the permanent records that are now written to disk as a result of processing this message. In all other cases the value of <span class="bold"><strong>ret_lsnp</strong></span> is undefined. </p> </div> </div> <div class="sect2" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h3 class="title"><a id="id1697758"></a>Errors</h3> </div> </div> </div> <p> The <code class="methodname">DB_ENV->rep_process_message()</code> <span> <span> method may fail and return one of the following non-zero errors: </span> </span> </p> <div class="sect3" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h4 class="title"><a id="id1697279"></a>EINVAL</h4> </div> </div> </div> <p> If the database environment was not already configured to communicate with a replication group by a call to <a class="xref" href="reptransport.html" title="DB_ENV->rep_set_transport()">DB_ENV->rep_set_transport()</a>; if the database environment was not already opened; if this method is called from a Replication Manager application; or if an invalid flag value or parameter was specified. </p> </div> </div> <div class="sect2" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h3 class="title"><a id="id1697674"></a>Class</h3> </div> </div> </div> <p> <a class="link" href="env.html" title="Chapter 5. The DB_ENV Handle">DB_ENV</a> </p> </div> <div class="sect2" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h3 class="title"><a id="id1697492"></a>See Also</h3> </div> </div> </div> <p> <a class="xref" href="rep.html#replist" title="Replication and Related Methods">Replication and Related Methods</a> </p> </div> </div> <div class="navfooter"> <hr /> <table width="100%" summary="Navigation footer"> <tr> <td width="40%" align="left"><a accesskey="p" href="repget_timeout.html">Prev</a> </td> <td width="20%" align="center"> <a accesskey="u" href="rep.html">Up</a> </td> <td width="40%" align="right"> <a accesskey="n" href="repclockskew.html">Next</a></td> </tr> <tr> <td width="40%" align="left" valign="top">DB_ENV->rep_get_timeout() </td> <td width="20%" align="center"> <a accesskey="h" href="index.html">Home</a> </td> <td width="40%" align="right" valign="top"> DB_ENV->rep_set_clockskew()</td> </tr> </table> </div> </body> </html>