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<div class="title">Default Encoding under Microsoft Windows </div> </div>
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<div class="textblock"><p>All modern operating systems use Unicode.</p>
<ul>
<li>Unix operating system family use UTF-8 encoding by default.</li>
<li>Microsoft Windows had migrated to Wide/UTF-16 API. The narrow encodings had been deprecated and the native OS API became so called "Wide API"</li>
</ul>
<p>As a result of radically different approaches, it is very hard to write portable Unicode aware applications.</p>
<p>Boost Locale fully supports both narrow and wide API. The default character encoding is assumed to be UTF-8 on Windows.</p>
<p>So if the default operating system Locale is "English_USA.1252" the default locale for Boost.Locale on Windows would be "en_US.UTF-8".</p>
<p>When the created locale object is installed globally then any libraries that use <code>std::codecvt</code> for conversion between narrow API and the native wide API would handle UTF-8 correctly.</p>
<p>A good example of such library is Boost.Filesystem v3.</p>
<p>For example</p>
<div class="fragment"><pre class="fragment"><span class="preprocessor">#include <boost/locale.hpp></span>
<span class="preprocessor">#include <boost/filesystem/path.hpp></span>
<span class="preprocessor">#include <boost/filesystem/fstream.hpp></span>
<span class="keywordtype">int</span> main()
{
<span class="comment">// Create and install global locale</span>
std::locale::global(<a class="code" href="classboost_1_1locale_1_1generator.html" title="the major class used for locale generation">boost::locale::generator</a>().generate(<span class="stringliteral">""</span>));
<span class="comment">// Make boost.filesystem use it</span>
boost::filesystem::path::imbue(std::locale());
<span class="comment">// Now Works perfectly fine with UTF-8!</span>
boost::filesystem::ofstream hello(<span class="stringliteral">"שלום.txt"</span>);
}
</pre></div><p>However such behavior may break existing software that assumes that the current encoding is single byte encodings like code page 1252.</p>
<p><a class="el" href="classboost_1_1locale_1_1generator.html">boost::locale::generator</a> class has a property <a class="el" href="classboost_1_1locale_1_1generator.html#a9afb2b0791abbabd39c800e08d9c9717">use_ansi_encoding()</a> that allows to change the behavior to legacy one and select an ANSI code page as default system encoding.</p>
<p>So, when the current locale is "English_USA.1252" and the <code>use_ansi_encoding</code> is turned on then the default locale would be "en_US.windows-1252"</p>
<dl class="note"><dt><b>Note:</b></dt><dd><code>winapi</code> backend does not support ANSI encodings, thus UTF-8 encoding is always used for narrow characters. </dd></dl>
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© Copyright 2009-2012 Artyom Beilis, Distributed under the <a href="http://www.boost.org/LICENSE_1_0.txt">Boost Software License</a>, Version 1.0.
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