1<?xml version="1.0" encoding="UTF-8" standalone="no"?> 2<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 3<html xmlns="http://www.w3.org/1999/xhtml"> 4 <head> 5 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> 6 <title>DB_MPOOLFILE->get_fileid()</title> 7 <link rel="stylesheet" href="apiReference.css" type="text/css" /> 8 <meta name="generator" content="DocBook XSL Stylesheets V1.73.2" /> 9 <link rel="start" href="index.html" title="Berkeley DB C API Reference" /> 10 <link rel="up" href="memp.html" title="Chapter 8. The DB_MPOOLFILE Handle" /> 11 <link rel="prev" href="mempget_clear_len.html" title="DB_MPOOLFILE->get_clear_len()" /> 12 <link rel="next" href="mempget_flags.html" title="DB_MPOOLFILE->get_flags()" /> 13 </head> 14 <body> 15 <div class="navheader"> 16 <table width="100%" summary="Navigation header"> 17 <tr> 18 <th colspan="3" align="center">DB_MPOOLFILE->get_fileid()</th> 19 </tr> 20 <tr> 21 <td width="20%" align="left"><a accesskey="p" href="mempget_clear_len.html">Prev</a> </td> 22 <th width="60%" align="center">Chapter 8. 23 The DB_MPOOLFILE Handle 24 </th> 25 <td width="20%" align="right"> <a accesskey="n" href="mempget_flags.html">Next</a></td> 26 </tr> 27 </table> 28 <hr /> 29 </div> 30 <div class="sect1" lang="en" xml:lang="en"> 31 <div class="titlepage"> 32 <div> 33 <div> 34 <h2 class="title" style="clear: both"><a id="mempget_fileid"></a>DB_MPOOLFILE->get_fileid()</h2> 35 </div> 36 </div> 37 </div> 38 <pre class="programlisting">#include <db.h> 39 40int 41DB_MPOOLFILE->get_fileid(DB_MPOOLFILE *mpf, u_int8_t *fileid); </pre> 42 <p> 43 The <code class="methodname">DB_MPOOLFILE->get_fileid()</code> method copies the 44 file's identifier into the memory location referenced by <span class="bold"><strong>fileid</strong></span>. The fileid specifies a unique 45 identifier for the file, which is used so that the cache functions 46 (that is, the shared memory buffer pool functions) are able to 47 uniquely identify files. This is necessary for multiple processes 48 wanting to share a file to correctly identify the file in the 49 cache. 50 </p> 51 <p> 52 The <code class="methodname">DB_MPOOLFILE->get_fileid()</code> <span> 53 <span> 54 method returns a non-zero error value on failure and 0 on success. 55 </span> 56 57 </span> 58 </p> 59 <div class="sect2" lang="en" xml:lang="en"> 60 <div class="titlepage"> 61 <div> 62 <div> 63 <h3 class="title"><a id="id1690951"></a>Class</h3> 64 </div> 65 </div> 66 </div> 67 <p> 68 <a class="link" href="env.html" title="Chapter 5. The DB_ENV Handle">DB_ENV</a>, <a class="link" href="memp.html" title="Chapter 8. The DB_MPOOLFILE Handle">DB_MPOOLFILE</a> 69 </p> 70 </div> 71 <div class="sect2" lang="en" xml:lang="en"> 72 <div class="titlepage"> 73 <div> 74 <div> 75 <h3 class="title"><a id="id1690998"></a>See Also</h3> 76 </div> 77 </div> 78 </div> 79 <p> 80 <a class="xref" href="memp.html#memplist" title="Memory Pools and Related Methods">Memory Pools and Related Methods</a>, 81 <a class="xref" href="mempset_fileid.html" title="DB_MPOOLFILE->set_fileid()">DB_MPOOLFILE->set_fileid()</a> 82 </p> 83 </div> 84 </div> 85 <div class="navfooter"> 86 <hr /> 87 <table width="100%" summary="Navigation footer"> 88 <tr> 89 <td width="40%" align="left"><a accesskey="p" href="mempget_clear_len.html">Prev</a> </td> 90 <td width="20%" align="center"> 91 <a accesskey="u" href="memp.html">Up</a> 92 </td> 93 <td width="40%" align="right"> <a accesskey="n" href="mempget_flags.html">Next</a></td> 94 </tr> 95 <tr> 96 <td width="40%" align="left" valign="top">DB_MPOOLFILE->get_clear_len() </td> 97 <td width="20%" align="center"> 98 <a accesskey="h" href="index.html">Home</a> 99 </td> 100 <td width="40%" align="right" valign="top"> DB_MPOOLFILE->get_flags()</td> 101 </tr> 102 </table> 103 </div> 104 </body> 105</html> 106