libdb/docs/api_reference/CXX/envset_tmp_dir.html
2011-09-13 13:44:24 -04:00

257 lines
9.9 KiB
HTML
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

<?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>DbEnv::set_tmp_dir()</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="env.html" title="Chapter 5.  The DbEnv Handle" />
<link rel="prev" href="envset_timeout.html" title="DbEnv::set_timeout()" />
<link rel="next" href="envset_verbose.html" title="DbEnv::set_verbose()" />
</head>
<body>
<div xmlns="" class="navheader">
<div class="libver">
<p>Library Version 11.2.5.2</p>
</div>
<table width="100%" summary="Navigation header">
<tr>
<th colspan="3" align="center">DbEnv::set_tmp_dir()</th>
</tr>
<tr>
<td width="20%" align="left"><a accesskey="p" href="envset_timeout.html">Prev</a> </td>
<th width="60%" align="center">Chapter 5. 
The DbEnv Handle
</th>
<td width="20%" align="right"> <a accesskey="n" href="envset_verbose.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="envset_tmp_dir"></a>DbEnv::set_tmp_dir()</h2>
</div>
</div>
</div>
<pre class="programlisting">#include &lt;db_cxx.h&gt;
int
DbEnv::set_tmp_dir(const char *dir); </pre>
<p>
Specify the path of a directory to be used as the location of
temporary files. The files created to back in-memory access method
databases will be created relative to this path. These temporary
files can be quite large, depending on the size of the database.
</p>
<p>
If no directories are specified, the following alternatives are
checked in the specified order. The first existing directory path is
used for all temporary files.
</p>
<div class="orderedlist">
<ol type="1">
<li>
<p>
The value of the environment variable <span class="bold"><strong>TMPDIR</strong></span>.
</p>
</li>
<li>
<p>
The value of the environment variable <span class="bold"><strong>TEMP</strong></span>.
</p>
</li>
<li>
<p>
The value of the environment variable <span class="bold"><strong>TMP</strong></span>.
</p>
</li>
<li>
<p>
The value of the environment variable <span class="bold"><strong>TempFolder</strong></span>.
</p>
</li>
<li>
<p>
The value returned by the <span class="bold"><strong>GetTempPath</strong></span> interface.
</p>
</li>
<li>
<p>
The directory <span class="bold"><strong>/var/tmp</strong></span>.
</p>
</li>
<li>
<p>
The directory <span class="bold"><strong>/usr/tmp</strong></span>.
</p>
</li>
<li>
<p>
The directory <span class="bold"><strong>/temp</strong></span>.
</p>
</li>
<li>
<p>
The directory <span class="bold"><strong>/tmp</strong></span>.
</p>
</li>
<li>
<p>
The directory <span class="bold"><strong>C:/temp</strong></span>.
</p>
</li>
<li>
<p>
The directory <span class="bold"><strong>C:/tmp</strong></span>.
</p>
</li>
</ol>
</div>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<h3 class="title">Note</h3>
<p>
Environment variables are only checked if one of the
<a class="link" href="envopen.html#envopen_DB_USE_ENVIRON">DB_USE_ENVIRON</a> or
<a class="link" href="envopen.html#envopen_DB_USE_ENVIRON_ROOT">DB_USE_ENVIRON_ROOT</a>
flags were specified.
</p>
</div>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<h3 class="title">Note</h3>
<p>
The GetTempPath interface is only checked on Win/32 platforms.
</p>
</div>
<p>
The database environment's temporary file directory may also be
configured using the environment's <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file. The syntax
of the entry in that file is a single line with the string
"set_tmp_dir", one or more whitespace characters, and the
directory name. Because the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file is read when the
database environment is opened, it will silently overrule
configuration done before that time.
</p>
<p>
The <code class="methodname">DbEnv::set_tmp_dir()</code> method configures operations performed
using the specified <a class="link" href="env.html" title="Chapter 5.  The DbEnv Handle">DbEnv</a> handle, not all
operations performed on the underlying database environment.
</p>
<p>
The <code class="methodname">DbEnv::set_tmp_dir()</code> <span>
<span>
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.
</span>
</span>
</p>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="id3628149"></a>Parameters</h3>
</div>
</div>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id3627324"></a>dir</h4>
</div>
</div>
</div>
<p>
The <span class="bold"><strong>dir</strong></span> parameter is the directory to
be used to store temporary files.
</p>
<p>
When using a Unicode build on Windows (the default), the this argument will be interpreted
as a UTF-8 string, which is equivalent to ASCII for Latin characters.
</p>
</div>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="id3628194"></a>Errors</h3>
</div>
</div>
</div>
<p>
The <code class="methodname">DbEnv::set_tmp_dir()</code> <span>
<span>
method may fail and throw a <a class="link" href="dbexception.html" title="Chapter 6. The DbException Class">DbException</a>
exception, encapsulating one of the following non-zero errors, or 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="id3628283"></a>EINVAL</h4>
</div>
</div>
</div>
<p>
If the method was called after <a class="xref" href="envopen.html" title="DbEnv::open()">DbEnv::open()</a>
was called; 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="id3628021"></a>Class</h3>
</div>
</div>
</div>
<p>
<a class="link" href="env.html" title="Chapter 5.  The DbEnv Handle">DbEnv</a>
</p>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="id3627892"></a>See Also</h3>
</div>
</div>
</div>
<p>
<a class="xref" href="env.html#envlist" title="Database Environments and Related Methods">Database Environments 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="envset_timeout.html">Prev</a> </td>
<td width="20%" align="center">
<a accesskey="u" href="env.html">Up</a>
</td>
<td width="40%" align="right"> <a accesskey="n" href="envset_verbose.html">Next</a></td>
</tr>
<tr>
<td width="40%" align="left" valign="top">DbEnv::set_timeout() </td>
<td width="20%" align="center">
<a accesskey="h" href="index.html">Home</a>
</td>
<td width="40%" align="right" valign="top"> DbEnv::set_verbose()</td>
</tr>
</table>
</div>
</body>
</html>