1<!--$Id: memp_set_pgcookie.so,v 10.17 2005/11/30 19:46:21 bostic Exp $-->
2<!--Copyright (c) 1997,2008 Oracle.  All rights reserved.-->
3<!--See the file LICENSE for redistribution information.-->
4<html>
5<head>
6<title>Berkeley DB: DbMpoolFile::set_pgcookie</title>
7<meta name="description" content="Berkeley DB: An embedded database programmatic toolkit.">
8<meta name="keywords" content="embedded,database,programmatic,toolkit,btree,hash,hashing,transaction,transactions,locking,logging,access method,access methods,Java,C,C++">
9</head>
10<body bgcolor=white>
11<table width="100%"><tr valign=top>
12<td>
13<b>DbMpoolFile::set_pgcookie</b>
14</td>
15<td align=right>
16<a href="../api_cxx/api_core.html"><img src="../images/api.gif" alt="API"></a>
17<a href="../ref/toc.html"><img src="../images/ref.gif" alt="Ref"></a></td>
18</tr></table>
19<hr size=1 noshade>
20<tt>
21<b><pre>
22#include &lt;db_cxx.h&gt;
23<p>
24int
25DbMpoolFile::set(DBT *pgcookie);
26<p>
27int
28DbMpoolFile::get_pgcookie(DBT *dbt);
29</pre></b>
30<hr size=1 noshade>
31<b>Description: DbMpoolFile::set_pgcookie</b>
32<p>The DbMpoolFile::set_pgcookie method specifies a byte string that is provided
33to the functions registered to do input or output processing of the
34file's pages as they are read from or written to, the backing filesystem
35store.  (See the <a href="../api_cxx/memp_register.html">DbEnv::memp_register</a> documentation for more
36information.)</p>
37<p>The DbMpoolFile::set_pgcookie method configures a file in the memory pool, not only
38operations performed using the specified <a href="../api_cxx/mempfile_class.html">DbMpoolFile</a> handle.</p>
39<p>The DbMpoolFile::set_pgcookie method may not be called after the <a href="../api_cxx/memp_fopen.html">DbMpoolFile::open</a> method is
40called.
41If the file is already open in the memory pool when
42<a href="../api_cxx/memp_fopen.html">DbMpoolFile::open</a> is called, the information specified to DbMpoolFile::set_pgcookie
43will replace the existing information.</p>
44<p>The DbMpoolFile::set_pgcookie method
45either returns a non-zero error value
46or throws an exception that encapsulates a non-zero error value on
47failure, and returns 0 on success.
48</p>
49<b>Parameters</b> <br>
50 <b>pgcookie</b><ul compact><li>The <b>pgcookie</b> parameter is a byte string provided to the
51functions registered to do input or output processing of the file's
52pages.</ul>
53<br>
54<hr size=1 noshade>
55<b>Description: DbMpoolFile::get_pgcookie</b>
56<p>The DbMpoolFile::get_pgcookie method returns the byte string.</p>
57<p>The DbMpoolFile::get_pgcookie method may be called at any time during the life of the
58application.</p>
59<p>The DbMpoolFile::get_pgcookie method
60either returns a non-zero error value
61or throws an exception that encapsulates a non-zero error value on
62failure, and returns 0 on success.
63</p>
64<b>Parameters</b> <br>
65 <b>dbt</b><ul compact><li>The DbMpoolFile::get_pgcookie method returns a reference to the
66byte string in <b>dbt</b>.</ul>
67<br>
68<hr size=1 noshade>
69<br><b>Class</b>
70<a href="../api_cxx/env_class.html">DbEnv</a>, <a href="../api_cxx/mempfile_class.html">DbMpoolFile</a>
71<br><b>See Also</b>
72<a href="../api_cxx/memp_list.html">Memory Pools and Related Methods</a>
73</tt>
74<table width="100%"><tr><td><br></td><td align=right>
75<a href="../api_cxx/api_core.html"><img src="../images/api.gif" alt="API"></a><a href="../ref/toc.html"><img src="../images/ref.gif" alt="Ref"></a>
76</td></tr></table>
77<p><font size=1>Copyright (c) 1996,2008 Oracle.  All rights reserved.</font>
78</body>
79</html>
80