title: string conversion with boost locale: different behaviour on windows and linux
body: <p>This is my sample code:</p>
  
  <pre><code>#pragma execution_character_set("utf-8")
  
  #include &lt;boost/locale.hpp&gt;
  #include &lt;boost/algorithm/string/case_conv.hpp&gt;
  #include &lt;iostream&gt;
  
  int main()
  {
      std::locale loc = boost::locale::generator().generate("");
      std::locale::global(loc);
  
  #ifdef MSVC
      std::cout &lt;&lt; boost::locale::conv::from_utf("grüßen vs ", "ISO8859-15");
      std::cout &lt;&lt; boost::locale::conv::from_utf(boost::locale::to_upper("grüßen"), "ISO8859-15") &lt;&lt; std::endl;
      std::cout &lt;&lt; boost::locale::conv::from_utf(boost::locale::fold_case("grüßen"), "ISO8859-15") &lt;&lt; std::endl;
      std::cout &lt;&lt; boost::locale::conv::from_utf(boost::locale::normalize("grüßen", boost::locale::norm_nfd), "ISO8859-15") &lt;&lt; std::endl;
  #else
      std::cout &lt;&lt; "grüßen vs ";
      std::cout &lt;&lt; boost::locale::to_upper("grüßen") &lt;&lt; std::endl;
      std::cout &lt;&lt; boost::locale::fold_case("grüßen") &lt;&lt; std::endl;
      std::cout &lt;&lt; boost::locale::normalize("grüßen", boost::locale::norm_nfd) &lt;&lt; std::endl;
  #endif
  
      return 0;
  }
  </code></pre>
  
  <p>Output on Windows 7 is:</p>
  
  <pre><code>grüßen vs GRÜßEN
  grüßen
  grußen
  </code></pre>
  
  <p>Output on Linux (openSuSE 12.3) is:</p>
  
  <pre><code>grüßen vs GRÜSSEN
  grüssen
  grüßen
  </code></pre>
  
  <p>On Linux the german letter 'ß' is converted to 'SS' as predicted, while this character remains unchanged on Windows.</p>
  
  <p>Question: why is this so? How can I correct the conversion?</p>
  
  <p>Some notes: Windows console codepage is set to 1252. In both cases locales are set to de_DE. I tried to replace the default locale setting in the listing above by "de_DE.UTF-8" - without any effect.
  On Windows this code is compiled with Visual Studio 2013, on Linux with GCC 4.7, c++11 enabled.</p>
  
  <p>Any suggestions are appreciated - thanks in advance for your support!</p>