<!--$Id: db_sync.so,v 10.35 2003/10/31 17:24:39 bostic Exp $--> <!--Copyright 1997-2003 by Sleepycat Software, Inc.--> <!--All rights reserved.--> <!--See the file LICENSE for redistribution information.--> <html> <head> <title>Berkeley DB: Db::sync</title> <meta name="description" content="Berkeley DB: An embedded database programmatic toolkit."> <meta name="keywords" content="embedded,database,programmatic,toolkit,b+tree,btree,hash,hashing,transaction,transactions,locking,logging,access method,access methods,Java,C,C++"> </head> <body bgcolor=white> <a name="2"><!--meow--></a> <table width="100%"><tr valign=top> <td> <h3>Db::sync</h3> </td> <td align=right> <a href="../../db42-devel-4.2.52/api_cxx/api_index.html"><img src="../../db42-4.2.52/images/api.gif" alt="API"></a> <a href="../../db42-devel-4.2.52/ref/toc.html"><img src="../../db42-4.2.52/images/ref.gif" alt="Ref"></a> </td></tr></table> <hr size=1 noshade> <tt> <h3><pre> #include <db_cxx.h> <p> int Db::sync(u_int32_t flags); </pre></h3> <hr size=1 noshade> <h3>Description: Db::sync</h3> <p>The Db::sync method flushes any cached information to disk.</p> <p>If the database is in memory only, the Db::sync method has no effect and will always succeed.</p> <p><b>It is important to understand that flushing cached information to disk only minimizes the window of opportunity for corrupted data.</b> Although unlikely, it is possible for database corruption to happen if a system or application crash occurs while writing data to the database. To ensure that database corruption never occurs, applications must either: use transactions and logging with automatic recovery; use logging and application-specific recovery; or edit a copy of the database, and once all applications using the database have successfully called <a href="../../db42-devel-4.2.52/api_cxx/db_close.html">Db::close</a>, atomically replace the original database with the updated copy.</p> <p>The Db::sync method either returns a non-zero error value or throws an exception that encapsulates a non-zero error value on failure, and returns 0 on success. </p> <h3>Parameters</h3> <p><dl compact> <p><dt><b>flags</b><dd> The <b>flags</b> parameter is currently unused, and must be set to 0. </dl> <h3>Errors</h3> <p>The Db::sync method may fail and throw <a href="../../db42-devel-4.2.52/api_cxx/except_class.html">DbException</a>, encapsulating one of the following non-zero errors, or return one of the following non-zero errors:</p> <p><dl compact> <p><dt>DB_REP_HANDLE_DEAD<dd>The database handle has been invalidated because a replication election unrolled a committed transaction. </dl> <p><dl compact> <p><dt>EINVAL<dd>An invalid flag value or parameter was specified. </dl> <hr size=1 noshade> <h3>Class</h3> <a href="../../db42-devel-4.2.52/api_cxx/db_class.html">Db</a> <h3>See Also</h3> <a href="../../db42-devel-4.2.52/api_cxx/db_list.html">Databases and Related Methods</a> </tt> <table width="100%"><tr><td><br></td><td align=right> <a href="../../db42-devel-4.2.52/api_cxx/api_index.html"><img src="../../db42-4.2.52/images/api.gif" alt="API"></a><a href="../../db42-devel-4.2.52/ref/toc.html"><img src="../../db42-4.2.52/images/ref.gif" alt="Ref"></a> </td></tr></table> <p><font size=1><a href="../../db42-devel-4.2.52/sleepycat/legal.html">Copyright (c) 1996-2003</a> <a href="http://www.sleepycat.com">Sleepycat Software, Inc.</a> - All rights reserved.</font> </body> </html>