1<html> 2 3<head> 4<meta name="GENERATOR" content="Microsoft FrontPage 5.0"> 5<meta name="ProgId" content="FrontPage.Editor.Document"> 6<meta http-equiv="Content-Type" content="text/html; charset=utf-8"> 7<title>Filesystem V3 Intro</title> 8<link href="styles.css" rel="stylesheet"> 9 10<body> 11 12<table border="0" cellpadding="5" cellspacing="0" style="border-collapse: collapse" bordercolor="#111111"> 13 <tr> 14 <td width="277"> 15<a href="../../../index.htm"> 16<img src="../../../boost.png" alt="boost.png (6897 bytes)" align="middle" width="300" height="86" border="0"></a></td> 17 <td align="middle"> 18 <font size="7">Filesystem 19 Version 3<br> 20 Introduction</font></td> 21 </tr> 22</table> 23 24<table border="0" cellpadding="5" cellspacing="0" style="border-collapse: collapse" 25 bordercolor="#111111" bgcolor="#D7EEFF" width="100%"> 26 <tr> 27 <td><a href="index.htm">Home</a> 28 <a href="tutorial.html">Tutorial</a> 29 <a href="reference.html">Reference</a> 30 <a href="faq.htm">FAQ</a> 31 <a href="release_history.html">Releases</a> 32 <a href="portability_guide.htm">Portability</a> 33 <a href="v3.html">V3 Intro</a> 34 <a href="v3_design.html">V3 Design</a> 35 <a href="deprecated.html">Deprecated</a> 36 <a href="issue_reporting.html">Bug Reports </a> 37 </td> 38</table> 39 40<h1>Boost Filesystem Version 3</h1> 41 42<p>Version 3 is a major revision of the Boost Filesystem library. Important 43changes include:</p> 44 45<ul> 46 <li>A single class <code>path</code> handles all aspects of 47 internationalization, replacing the previous template and its <code>path</code> 48 and <code>wpath</code> instantiations. Character types <code>char</code>, 49 <code>wchar_t</code>, <code>char16_t</code>, and <code>char32_t</code> are 50 supported. This is a major simplification of the path abstraction, 51 particularly for functions that take path arguments.<br> 52 </li> 53 <li>New <code>class path</code> members include:<br> 54 <ul> 55 <li><code><a href="reference.html#path-has_stem">has_stem</a>()</code></li> 56 <li><code><a href="reference.html#path-has_extension">has_extension</a>()</code></li> 57 <li><code><a href="reference.html#path-is_absolute">is_absolute</a>()</code>. This renames <code>is_complete()</code>, which 58 is now deprecated.</li> 59 <li><code><a href="reference.html#path-is_relative">is_relative</a>()</code></li> 60 <li><code><a href="reference.html#path-make_preferred">make_preferred</a>()<br> 61 </code></li> 62</ul> 63 64 </li> 65 <li>New or improved operations functions include:<br> 66 <ul> 67 <li><code><a href="reference.html#absolute">absolute</a>()</code>. This replaces the operations function <code> 68 complete()</code>, which is now deprecated. Semantics are now provided for a 69 Windows corner case where the <code>base</code> argument was not an absolute 70 path. Previously this resulted in an exception being thrown.</li> 71 <li><code><a href="reference.html#create_symlink">create_symlink</a>()</code> now supported on both POSIX and Windows.</li> 72 <li><code><a href="reference.html#read_symlink">read_symlink</a>()</code> function added. Supported on both POSIX and 73 Windows. Used to read the contents of a symlink itself.</li> 74 <li><code><a href="reference.html#resize_file">resize_file</a>()</code> function added. Supported on both POSIX and 75 Windows. Used to shrink or grow a regular file.</li> 76 <li><code><a href="reference.html#unique_path">unique_path</a>()</code> function added. Supported on both POSIX and 77 Windows. Used to generate a secure temporary pathname.<br> 78 </li> 79 </ul> 80 </li> 81 <li>Support for error reporting via <code>error_code</code> is now uniform 82 throughout the operations functions.<br> 83 </li> 84 <li>Documentation has been reworked, including re-writes of major portions.<br> 85 </li> 86 <li>A new <a href="tutorial.html">Tutorial</a> provides a hopefully much 87 gentler and more complete introduction for new users. Current users might want 88 to review the <a href="tutorial.html">three sections related to class path</a>.</li> 89</ul> 90 91<h2>Deprecated names and other features</h2> 92 93<p>See the <a href="deprecated.html">Deprecated Features page</a> for transition 94aids that allow much existing code to compile without change using Version 3.</p> 95 96<h2>Breaking changes</h2> 97 98<p>To ease the transition, Versions 2 and 3 will both be included in the next 99several Boost releases. Version 2 will be the default version for one release 100cycle, and then Version 3 will become the default version.</p> 101<h3>Class <code>path</code></h3> 102<ul> 103 <li>Class template <code>basic_path</code> and its specializations are 104 replaced by a single <code>class path</code>. Thus any code, such as 105 overloaded functions, that depends on <code>path</code> and <code>wpath</code> 106 being two distinct types will fail to compile and must be restructured. 107 Restructuring may be as simple as removing one of the overloads, but also 108 might require more complex redesign.<br> 109 </li> 110 <li>Certain functions now return <code>path</code> objects rather than <code> 111 string or wstring</code> objects:<ul> 112 <li><code>root_name()</code></li> 113 <li><code>root_directory()</code></li> 114 <li><code>filename()</code></li> 115 <li><code>stem()</code></li> 116 <li><code>extension()</code></li> 117 </ul> 118 <p>Not all uses will fail; if the function is being called in a context that 119 accepts a <code>path</code>, all is well. If the result is being used in a 120 context requiring a <code>std::string</code> or <code>std::wstring</code>, 121 then <code>.string()</code> or <code>.wstring()</code> respectively must be 122 appended to the function call.<br> 123 </li> 124 <li> <code>path::iterator::value_type</code> and <code> 125 path::const_iterator::value_type</code> is <code>path</code> rather than <code> 126 basic_string</code>.</li> 127</ul> 128<h3>Compiler support</h3> 129<ul> 130 <li>Compilers and standard libraries that do not fully support wide characters 131 and wide character strings (<code>std::wstring</code>) are no longer 132 supported.<br> 133 </li> 134 <li>Cygwin versions prior to 1.7 are no longer supported because they lack 135 wide string support. Cygwin now compiles only for the Windows API and path 136 syntax.<br> 137 </li> 138 <li>MinGW versions not supporting wide strings are no longer supported.<br> 139 </li> 140 <li>Microsoft VC++ 7.1 and earlier are no longer supported.</li> 141</ul> 142 143<hr> 144<p>© Copyright Beman Dawes, 2009</p> 145<p>Distributed under the Boost Software License, Version 1.0. See 146<a href="http://www.boost.org/LICENSE_1_0.txt">www.boost.org/LICENSE_1_0.txt</a></p> 147<p>Revised 148<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B %Y" startspan -->29 December 2014<!--webbot bot="Timestamp" endspan i-checksum="39176" --></p> 149 150</body> 151 152</html> 153
