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    <font size="7">Filesystem Library<br>
    Version 2</font>
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    <td><a href="../../../../index.htm">Boost Home</a>&nbsp;&nbsp;&nbsp;
    <a href="index.htm">Library Home</a>&nbsp; &nbsp; <a href="#tutorial">Tutorial</a>&nbsp; &nbsp; <a href="reference.html">
    Reference</a>&nbsp;&nbsp; <a href="faq.htm">FAQ</a></td>
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      <i><b>Contents</b></i></td>
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    <td width="100%" bgcolor="#E8F5FF">
    <a href="#Introduction">Introduction</a><br>
    <a href="#Using">Using the library</a><br>
    <a href="#tutorial">Two-minute tutorial</a><br>
    <a href="#Cautions">Cautions</a><br>
    <a href="#Examples">Example programs</a><br>
    <a href="#Implementation">Implementation</a><br>
    <a href="#Macros">Macros</a><br>
    <a href="#Deprecated-names">Deprecated names and features</a><br>
    <a href="#narrow-only">Using only narrow character paths</a><br>
    <a href="#Building">Building the object-library</a><br>
    &nbsp;&nbsp;&nbsp;&nbsp;<a href="#Cgywin">Notes for Cygwin users</a><br>
    <a href="#Acknowledgements">Acknowledgements</a><br>
    <a href="#Change-history">Change history</a></td>
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      <i><b>Other Documents</b></i></td>
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    <td width="100%" bgcolor="#E8F5FF">
    <a href="reference.html">Reference</a><br>
    <a href="design.htm">Library Design</a><br>
    <a href="faq.htm">FAQ</a><br>
    <a href="portability_guide.htm">Portability Guide</a><br>
    <a href="do-list.htm">Do-list</a>
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  <center>
  <table border="1" cellpadding="10" cellspacing="1" style="border-collapse: collapse" bordercolor="#111111">
    <tr>
      <td>
      <p align="center"><b>This is Version 2 of the Filesystem library.</b></p>
      <p align="center"><a href="../../v3/doc/index.htm">Version 3</a>, a major revision with many new and improved 
      features is also available, but breaks some existing code.</p>
      <p align="center">Version 2 is the default version for Boost release 1.44 
      only. Version 3 will become the default starting with release 1.45.</p>
      <p align="center">Existing code should be moved to version 3 as soon as 
      convenient. New code should be written for version 3.</p>
      <p align="center">Version 2 is deprecated, and will be removed from Boost 
      releases at the end of a transition period.</p>
      </td>
    </tr>
  </table>
  </center>
</div>

<h2><a name="Introduction">Introduction</a></h2>
<p>The Boost.Filesystem library provides portable facilities to query and 
manipulate paths, files, and directories.</p>

<p>The motivation for the library is the need to perform portable script-like operations from within C++ programs. The intent is not to 
compete with Python, Perl, or shell languages, but rather to provide portable filesystem 
operations when C++ is already the language of choice. The <a href="design.htm">
design</a> encourages, but does not require, safe and portable  usage.</p>

<p>Programs using the library are <b><i>portable</i></b>, both in the sense that 
the syntax of program code is portable, and the sense that the semantics or 
behavior of code is portable. The <a href="reference.html">generic path 
grammar</a> is another important aid to portability.</p>

<p>Usage is <i><b>safe</b></i> in the sense that errors cannot be ignored since most functions throw C++ 
exceptions when errors are detected. This is also convenient for users because 
it alleviates the&nbsp;need to explicitly check error 
return codes.</p>

<p>A proposal,
<a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2006/n1975.html">
N1975</a>, to include Boost.Filesystem in Technical Report 2 has been accepted 
by the C++ Standards Committee. The Boost.Filesystem library will stay in 
alignment with the TR2 Filesystem proposal as it works its way through the TR2 
process. Note, however, that namespaces and header granularity differs between 
Boost.Filesystem and the TR2 proposal.</p>

<p>The Boost.Filesystem library provides several&nbsp; headers:</p>

<ul>
  <li>Header &lt;<a href="../../../boost/filesystem.hpp">boost/filesystem.hpp</a>&gt; provides class <i>
  basic_path, </i>a portable mechanism for representing
      <a href="#path">paths</a> in C++ programs. Typedefs <i>path</i> and <i>
  wpath</i> ease the most common usages of <i>basic_path</i>. Operational 
  functions provide useful query and maintenance operations on files and directories. 
  Class <i>basic_directory_iterator</i> with typdefs <i>
  directory_iterator</i> and <i>wdirectory_iterator</i> provide iteration over 
  the contents of directories. Convenience functions and classes combine lower-level functionality 
  in useful ways.<br>
&nbsp;</li>
  <li>Header &lt;<a href="../../../boost/filesystem/fstream.hpp">boost/filesystem<i>/</i>fstream.hpp</a>&gt; provides the same components as the C++ Standard 
  Library's <i>fstream</i> header, except 
      that files are identified by <i>basic_path</i> objects rather that <i>char *</i>'s.</li>
</ul>
<h2><a name="Using">Using</a> the library</h2>
<p>Boost.Filesystem is implemented as a separately compiled library, so before 
using it you must install it in a location that can be found by your linker. See
<a href="#Building">Building the object-library</a>. </p>
<p>The library's <a href="../example">example directory</a> contains very simple 
scripts for building the <a href="#Examples">example programs</a> on various 
platforms. You can use these scripts to see what's needed to compile and link 
your own programs.</p>
<h2>Two-minute <a name="tutorial">tutorial</a></h2>
<p>(A
<a href="http://beans.seartipy.com/2006/05/10/boost-filesystem-library-writing-portable-c-programs-to-acess-the-filesystem/">
more elaborate tutorial</a> is also available from Tabrez Iqbal.)</p>
<p>First some preliminaries:</p>
<blockquote>
  <pre>#include &quot;boost/filesystem.hpp&quot;   // includes all needed Boost.Filesystem declarations
#include &lt;iostream&gt;               // for std::cout
using boost::filesystem;          // for ease of tutorial presentation;
                                  //  a namespace alias is preferred practice in real code</pre>
</blockquote>
<p>A <a href="reference.html#Class-template-basic_path">class <i>path</i></a> object can be created:</p>
<blockquote>
  <pre>path my_path( &quot;some_dir/file.txt&quot; );</pre>
</blockquote>
<p>The string passed to the <i>path</i> constructor may be in a
<a href="reference.html#Pathname-formats">portable generic path format</a> or an 
implementation-defined native operating system format. Access functions 
make <i>my_path</i> contents available to the underlying operating system API in an operating system dependent format, 
such as <code>&quot;some_dir:file.txt&quot;</code>, <code>&quot;[some_dir]file.txt&quot;</code>,
<code>&quot;some_dir/file.txt&quot;</code>, or whatever is appropriate for the  
operating system. If class <i>wpath</i> is used instead of class <i>path</i>, 
translation between wide and narrow character paths is performed automatically 
if necessary for the operating system.</p>
<p>Class <i>path</i> has conversion constructors from <i>const char*</i> and <i>
const std:: string&amp;</i>, so that even though the Filesystem Library 
functions used in the following code snippet have <i>const path&amp;</i> formal 
parameters, the user can just 
code C-style strings as actual arguments:</p>
<blockquote>
  <pre>remove_all( &quot;foobar&quot; );
create_directory( &quot;foobar&quot; );
ofstream file( &quot;foobar/cheeze&quot; );
file &lt;&lt; &quot;tastes good!\n&quot;;
file.close();
if ( !exists( &quot;foobar/cheeze&quot; ) )
  std::cout &lt;&lt; &quot;Something is rotten in foobar\n&quot;;</pre>
</blockquote>
<p>To make class <i>path</i> objects easy to use in expressions, <i>operator/</i> 
appends paths:</p>
<blockquote>
  <pre>ifstream file1( arg_path / &quot;foo/bar&quot; );
ifstream file2( arg_path / &quot;foo&quot; / &quot;bar&quot; );</pre>
</blockquote>
<p>The expressions <i>arg_path / &quot;foo/bar&quot;</i> and <i>arg_path / &quot;foo&quot; 
/ &quot;bar&quot;</i> yield identical results.</p>
<p>Paths can include references to the current directory, using &quot;<code>.</code>&quot; 
notation, and the parent directory, using &quot;<code>..</code>&quot; 
notation.</p>
<p><a href="reference.html#Class-template-basic_directory_iterator">Class <i>basic_directory_iterator</i></a> 
is an important component of the library. It provides an input iterator over the 
contents of a directory, with the value type being class <i>basic_path</i>. 
Typedefs <i>directory_iterator</i> and <i>wdirectory_iterator</i> are provided 
to cover the most common use cases.</p>
<p>The following function, given a directory path and a file name, recursively 
searches the directory and its sub-directories for the file name, returning a 
bool, and if successful, the path to the file that was found.&nbsp; The code 
below is extracted from a real program, slightly modified for clarity:</p>
<blockquote>
  <pre>bool find_file( const path &amp; dir_path,         // in this directory,
                const std::string &amp; file_name, // search for this name,
                path &amp; path_found )            // placing path here if found
{
  if ( !exists( dir_path ) ) return false;
  directory_iterator end_itr; // default construction yields past-the-end
  for ( directory_iterator itr( dir_path );
        itr != end_itr;
        ++itr )
  {
    if ( is_directory(itr-&gt;status()) )
    {
      if ( find_file( itr-&gt;path(), file_name, path_found ) ) return true;
    }
    else if ( itr-&gt;path().filename() == file_name ) // see below
    {
      path_found = itr-&gt;path();
      return true;
    }
  }
  return false;
}</pre>
</blockquote>
<p>The expression <i>itr-&gt;path().filename() == file_name</i>, in the line commented <i>// 
see below</i>, calls the <i>filename()</i> function on the <i>path</i> returned by 
calling the <i>path()</i> function of the <i>directory_entry </i>object pointed 
to by the iterator. <i>filename()</i> returns a string which is a copy of the 
last (closest to the leaf, farthest from the root) file or directory name in the
<i>path</i> object.</p>
<p>Notice that <i>find_file()</i> does not do explicit error checking, such as 
verifying that the <i>dir_path</i> argument really represents a directory.  
Boost.Filesystem  functions throw 
exceptions if they do not complete successfully, so there is enough implicit 
error checking that this application doesn't need to supply additional error 
checking code unless desired. Several Boost.Filesystem functions have non-throwing 
versions, to ease use cases where exceptions would not be appropriate.</p>
<blockquote>
<p><i>Note: </i>Recursive 
directory iteration was added  as a convenience function after the above tutorial code 
was written, so nowadays you 
don't have to actually code the recursion yourself.</p>
</blockquote>
<h2><a name="Cautions">Cautions</a></h2>
<p>After reading the tutorial you can dive right into  simple, 
script-like programs using the Filesystem Library! Before doing any serious 
work, however, there a few cautions to be aware of:</p>
<h4><b>Effects and Postconditions not guaranteed in the presence of race-conditions</b></h4>
<p>Filesystem function specifications follow the C++ Standard Library form, specifying behavior in terms of 
effects and postconditions. If 
a <a href="reference.html#Race-condition">race-condition</a> exists, a function's 
postconditions may no longer be true by the time the function returns to the 
caller.</p>
<blockquote>
<p><b><i>Explanation: </i></b>The state of files and directories is often
globally shared, and thus may be changed unexpectedly by other threads, 
processes, or even other computers having network access to the filesystem. As an 
example of the difficulties this can cause, note that the following asserts 
may fail:</p>
<blockquote>
<p><code>assert( exists( &quot;foo&quot; ) == exists( &quot;foo&quot; ) );&nbsp; // 
(1)<br>
<br>
remove_all( &quot;foo&quot; );<br>
assert( !exists( &quot;foo&quot; ) );&nbsp; // (2)<br>
<br>
assert( is_directory( &quot;foo&quot; ) == is_directory( &quot;foo&quot; ) ); // 
(3)</code></p>
</blockquote>
<p>(1) will fail if a non-existent &quot;foo&quot; comes into existence, or an 
existent &quot;foo&quot; is removed, between the first and second call to <i>exists()</i>. 
This could happen if, during the execution of the example code, another thread, 
process, or computer is also performing operations in the same directory.</p>
<p>(2) will fail if between the call to <i>remove_all()</i> and the call to
<i>exists()</i> a new file or directory named &quot;foo&quot; is created by another 
thread, process, or computer.</p>
<p>(3) will fail if another thread, process, or computer removes an 
existing file &quot;foo&quot; and then creates a directory named &quot;foo&quot;, between the 
example code's two calls to <i>is_directory()</i>.</p>
</blockquote>
<h4><b>May throw exceptions</b></h4>
<p>Unless otherwise specified, Boost.Filesystem functions throw <i>
<a href="reference.html#basic_filesystem_error-constructors">basic_filesystem_error</a></i> 
exceptions if they cannot successfully complete their operational 
specifications. Also, implementations may use C++ Standard Library functions, 
which may throw <i>std::bad_alloc</i>. These exceptions may be thrown even 
though the error condition leading to the exception is not explicitly specified 
in the function's &quot;Throws&quot; paragraph.</p>
<p>All exceptions thrown by the Filesystem 
Library are implemented by calling <a href="../../utility/throw_exception.html">
boost::throw_exception()</a>. Thus exact behavior may differ depending on 
BOOST_NO_EXCEPTIONS at the time the filesystem source files are compiled.</p>
<p>Non-throwing versions are provided of several functions that are often used 
in contexts where error codes may be the preferred way to report an error.</p>
<h2><a name="Examples">Example programs</a></h2>
<h3><a href="../example/simple_ls.cpp">simple_ls.cpp</a></h3>
<p>The example program <a href="../example/simple_ls.cpp">simple_ls.cpp</a> is 
given a path as a command line argument. Since the command line argument may be 
a relative path, the complete path is determined so that messages displayed 
can be more precise.</p>
<p>The program checks to see if the path exists; if not a message is printed.</p>
<p>If the path identifies a directory, the directory is iterated through, 
printing the name of the entries found, and an indication if they are 
directories. A count of directories and files is updated, and then printed after 
the iteration is complete.</p>
<p>If the path is for a file, a message indicating that is printed.</p>
<p>Try compiling and executing <a href="../example/simple_ls.cpp">simple_ls.cpp</a> 
to see how it works on your system. Try various path arguments to see what 
happens.</p>
<h3><a href="../example/file_size.cpp">file_size.cpp</a></h3>
<p>This example program prints the file's size if it is a regular file.</p>
<h3>Other examples</h3>
<p>The programs used to generate the Boost regression test status tables use the 
Filesystem Library extensively.&nbsp; See:</p>
<ul>
  <li><a href="../../../tools/regression/src/process_jam_log.cpp">process_jam_log.cpp</a></li>
  <li><a href="../../../tools/regression/src/compiler_status.cpp">compiler_status.cpp</a></li>
</ul>
<p>Test programs are sometimes useful in understanding a library, as they 
illustrate what the developer expected to work and not work. See:</p>
<ul>
  <li><a href="../test/wide_test.cpp">wide_test.cpp</a></li>
  <li><a href="../test/path_test.cpp">path_test.cpp</a></li>
  <li><a href="../test/operations_test.cpp">operations_test.cpp</a></li>
  <li><a href="../test/fstream_test.cpp">fstream_test.cpp</a></li>
</ul>
<h2><a name="Implementation">Implementation</a></h2>
<p>The current implementation supports operating systems which provide 
either the POSIX or Windows API.</p>
<p>The library is in regular use on Apple  OS X, HP-UX, IBM AIX, Linux, 
Microsoft Windows, SGI IRIX, and Sun Solaris operating systems using a variety 
of compilers.</p>
<h2><a name="Macros">Macros</a></h2>
<p>Users may defined the following macros if desired. Sensible defaults are 
provided, so users can ignore these macros unless they have special needs.</p>
<table border="1" cellpadding="5" cellspacing="0" style="border-collapse: collapse" bordercolor="#111111">
  <tr>
    <td><b><i>Macro Name</i></b></td>
    <td><b><i>Default</i></b></td>
    <td><b><i>Effect if defined</i></b></td>
  </tr>
  <tr>
    <td valign="top"><code>BOOST_FILESYSTEM_DYN_LINK</code></td>
    <td valign="top">Defined if <code>BOOST_ALL_DYN_LINK</code> is defined, 
    otherwise not defined.</td>
    <td valign="top">Boost.System library is dynamically linked. If not defined, 
    static linking is assumed.</td>
  </tr>
  <tr>
    <td valign="top"><code>BOOST_FILESYSTEM_NO_LIB</code></td>
    <td valign="top">Defined if <code>BOOST_ALL_NO_LIB</code> is defined, 
    otherwise not defined.</td>
    <td valign="top">Boost.System library does not use the Boost auto-link 
    facility.</td>
  </tr>
  <tr>
    <td valign="top"><code>BOOST_FILESYSTEM_NARROW_ONLY</code></td>
    <td valign="top">Not defined.</td>
    <td valign="top">Removes features that require wchar_t support.</td>
  </tr>
  <tr>
    <td valign="top"><code>BOOST_FILESYSTEM_NO_DEPRECATED</code></td>
    <td valign="top">Not defined.</td>
    <td valign="top">Deprecated features are excluded.</td>
  </tr>
</table>
<h2><a name="Deprecated-names">Deprecated names</a> and features</h2>
<p style="font-size: 10pt">User-defined BOOST_POSIX_API and BOOST_WINDOWS_API 
macros are no longer supported.</p>
<p style="font-size: 10pt">As the library evolves over time, names sometimes 
change or features are removed. To ease transition, Boost.Filesystem deprecates 
the old names and features, but continues to provide them unless macro <code>
BOOST_FILESYSTEM_NO_DEPRECATED</code> is defined.</p>
<table border="1" cellpadding="5" cellspacing="1" style="border-collapse: collapse" bordercolor="#111111">
  <tr>
    <td style="font-size: 10pt">
    <b><i>Component</i></b></td>
    <td style="font-size: 10pt">
    <p style="font-size: 10pt"><b><i>Old name, now deprecated</i></b></td>
    <td style="font-size: 10pt">
    <p style="font-size: 10pt"><b><i>New name</i></b></td>
  </tr>
  <tr>
    <td style="font-size: 10pt" valign="top"><code>basic_path</code></td>
    <td style="font-size: 10pt"><code>leaf()</code></td>
    <td style="font-size: 10pt"><code>filename()</code></td>
  </tr>
  <tr>
    <td style="font-size: 10pt" valign="top"><code>basic_path</code></td>
    <td style="font-size: 10pt"><code>branch_path()</code></td>
    <td style="font-size: 10pt"><code>parent_path()</code></td>
  </tr>
  <tr>
    <td style="font-size: 10pt" valign="top"><code>basic_path</code></td>
    <td style="font-size: 10pt"><code>has_leaf()</code></td>
    <td style="font-size: 10pt"><code>has_filename()</code></td>
  </tr>
  <tr>
    <td style="font-size: 10pt" valign="top"><code>basic_path</code></td>
    <td style="font-size: 10pt"><code>has_branch_path()</code></td>
    <td style="font-size: 10pt"><code>has_parent_path()</code></td>
  </tr>
  <tr>
    <td style="font-size: 10pt" valign="top">
    <code>basic_path</code></td>
    <td style="font-size: 10pt">
    <p style="font-size: 10pt"><code>remove_leaf()</code></td>
    <td style="font-size: 10pt">
    <p style="font-size: 10pt"><code>remove_filename()</code></td>
  </tr>
  <tr>
    <td style="font-size: 10pt" valign="top">
    <code>basic_path</code></td>
    <td style="font-size: 10pt">
    <code>basic_path( const string_type &amp; str,<br>
&nbsp; name_check )</code></td>
    <td style="font-size: 10pt">
    <i><code>feature removed</code></i></td>
  </tr>
  <tr>
    <td style="font-size: 10pt" valign="top">
    <code>basic_path</code></td>
    <td style="font-size: 10pt">
    <code>basic_path( const string_type::value_type * s,<br>
&nbsp; name_check )</code></td>
    <td style="font-size: 10pt">
    <i><code>feature removed</code></i></td>
  </tr>
  <tr>
    <td style="font-size: 10pt" valign="top">
    <code>basic_path</code></td>
    <td style="font-size: 10pt">
    <code>native_file_string()</code></td>
    <td style="font-size: 10pt">
    <code>file_string()</code></td>
  </tr>
  <tr>
    <td style="font-size: 10pt" valign="top">
    <code>basic_path</code></td>
    <td style="font-size: 10pt">
    <code>native_directory_string()</code></td>
    <td style="font-size: 10pt">
    <code>directory_string()</code></td>
  </tr>
  <tr>
    <td style="font-size: 10pt" valign="top">
    <code>basic_path</code></td>
    <td style="font-size: 10pt">
    <code>default_name_check_writable()</code></td>
    <td style="font-size: 10pt">
    <i><code>feature removed</code></i></td>
  </tr>
  <tr>
    <td style="font-size: 10pt" valign="top">
    <code>basic_path</code></td>
    <td style="font-size: 10pt">
    <code>default_name_check( name_check )</code></td>
    <td style="font-size: 10pt">
    <i><code>feature removed</code></i></td>
  </tr>
  <tr>
    <td style="font-size: 10pt" valign="top">
    <code>basic_path</code></td>
    <td style="font-size: 10pt">
    <code>default_name_check()</code></td>
    <td style="font-size: 10pt">
    <i><code>feature removed</code></i></td>
  </tr>
  <tr>
    <td style="font-size: 10pt" valign="top">
    <code>basic_path</code></td>
    <td style="font-size: 10pt">
    <code>canonize()</code></td>
    <td style="font-size: 10pt">
    <i><code>feature removed</code></i></td>
  </tr>
  <tr>
    <td style="font-size: 10pt" valign="top">
    <code>basic_path</code></td>
    <td style="font-size: 10pt">
    <code>normalize()</code></td>
    <td style="font-size: 10pt">
    <i><code>feature removed</code></i></td>
  </tr>
  <tr>
    <td style="font-size: 10pt" valign="top">
    <code>operations.hpp</code></td>
    <td style="font-size: 10pt">
    <code>is_regular( file_status f )</code></td>
    <td style="font-size: 10pt">
    <code>is_regular_file( file_status f )</code></td>
  </tr>
  <tr>
    <td style="font-size: 10pt" valign="top">
    <code>operations.hpp</code></td>
    <td style="font-size: 10pt">
    <code>symbolic_link_exists( const path &amp; ph )</code></td>
    <td style="font-size: 10pt">
    <i><code>feature removed</code></i></td>
  </tr>
  <tr>
    <td style="font-size: 10pt" valign="top">
    <code>basic_directory_status</code></td>
    <td style="font-size: 10pt">
    <code>filename()</code></td>
    <td style="font-size: 10pt">
    <i><code>feature removed, use path().filename() instead</code></i></td>
  </tr>
  <tr>
    <td style="font-size: 10pt" valign="top">
    <code>basic_directory_status</code></td>
    <td style="font-size: 10pt">
    <code>leaf()</code></td>
    <td style="font-size: 10pt">
    <i><code>feature removed, use path().filename() instead</code></i></td>
  </tr>
  <tr>
    <td style="font-size: 10pt" valign="top">
    <code>basic_directory_status</code></td>
    <td style="font-size: 10pt">
    <code>string()</code></td>
    <td style="font-size: 10pt">
    <i><code>feature removed, use path().string() instead</code></i></td>
  </tr>
</table>
<h2><a name="narrow-only">Restricting library to narrow character paths</a></h2>
<p>Compilers or standard libraries which do not support wide characters (wchar_t) 
or wide character strings (std::wstring) are detected automatically, and cause 
the library to compile code that is restricted to narrow character paths 
(boost::filesystem::path). Users can force this restriction by defining the 
macro BOOST_FILESYSTEM_NARROW_ONLY. That may be useful for dealing with legacy 
compilers or operating systems.</p>
<h2><a name="Building">Building</a> the object-library</h2>
<p>The object-library will  be built automatically if you are using the Boost 
build system. See
<a href="../../../more/getting_started.html">Getting Started</a>. It can also be 
built manually using a <a href="../build/Jamfile.v2">Jamfile</a> 
supplied in directory libs/filesystem/build, or the user can construct an IDE 
project or make file which includes the object-library source files.</p>
<p>The object-library source files are 
supplied in directory <a href="../src">libs/filesystem/src</a>. These source files implement the 
library for POSIX or Windows compatible operating systems; no implementation is 
supplied for other operating systems. Note that many operating systems not 
normally thought of as POSIX  systems, such as mainframe legacy 
operating systems or embedded operating systems, support POSIX compatible file 
systems which will work with the Filesystem Library.</p>
<p>The object-library can be built for static or dynamic (shared/dll) linking. 
This is controlled by the BOOST_ALL_DYN_LINK or BOOST_FILESYSTEM_DYN_LINK 
macros. See the <a href="http://www.boost.org/development/separate_compilation.html">Separate 
Compilation</a> page for a description of the techniques used.</p>
<h3>Note for <a name="Cgywin">Cygwin</a> users</h3>
<p>The library's implementation code treats <a href="http://www.cygwin.com/">Cygwin</a> 
as a Windows platform, and thus uses the Windows API.</p>
<h2><a name="Acknowledgements">Acknowledgements</a></h2>
<p>The Filesystem Library was designed and implemented by Beman Dawes. The 
original <i>directory_iterator</i> and <i>filesystem_error</i> classes were 
based on prior work from Dietmar Kuehl, as modified by Jan Langer. Thomas Witt 
was a particular help in later stages of initial development. Peter Dimov and 
Rob Stewart made many useful suggestions and comments over a long period of 
time. Howard Hinnant helped with internationalization issues.</p>

<p>Key <a href="design.htm#Requirements">design requirements</a> and
<a href="design.htm#Realities">design realities</a> were developed during 
extensive discussions on the Boost mailing list, followed by comments on the 
initial implementation. Numerous helpful comments were then received during the 
Formal Review.<p>Participants included 
Aaron Brashears,
Alan Bellingham,
Aleksey Gurtovoy,
Alex Rosenberg,
Alisdair Meredith,
Andy Glew,
Anthony Williams,
Baptiste Lepilleur, 
Beman Dawes,
Bill Kempf,
Bill Seymour, 
Carl Daniel,
Chris Little,
Chuck Allison,
Craig Henderson, 
Dan Nuffer,
Dan'l Miller,
Daniel Frey, 
Darin Adler, 
David Abrahams,
David Held, 
Davlet Panech,
Dietmar Kuehl,
Douglas Gregor, 
Dylan Nicholson,
Ed Brey, 
Eric Jensen,
Eric Woodruff,
Fedder Skovgaard,
Gary Powell,
Gennaro Prota,
Geoff Leyland, 
George Heintzelman, 
Giovanni Bajo,
Glen Knowles,
Hillel Sims,
Howard Hinnant,
Jaap Suter,
James Dennett, 
Jan Langer, 
Jani Kajala, 
Jason Stewart, 
Jeff Garland,
Jens Maurer,
Jesse Jones,
Jim Hyslop,
Joel de Guzman,
Joel Young,
John Levon, 
John Maddock,
John Williston,
Jonathan Caves,
Jonathan Biggar,
Jurko,
Justus Schwartz,
Keith Burton, 
Ken Hagen,
Kostya Altukhov, 
Mark Rodgers,
Martin Schuerch, 
Matt Austern,
Matthias Troyer, 
Mattias Flodin, 
Michiel Salters,
Mickael Pointier,
Misha Bergal,
Neal Becker,
Noel Yap,
Parksie,
Patrick Hartling, Pavel Vozenilek,
Pete Becker, 
Peter Dimov,
Rainer Deyke,
Rene Rivera,
Rob Lievaart,
Rob Stewart,
Ron Garcia,
Ross Smith,
Sashan,
Steve Robbins, 
Thomas Witt, 
Tom Harris, 
Toon Knapen,
Victor Wagner,
Vincent Finn,
Vladimir Prus, and
Yitzhak Sapir
 
<p>A lengthy discussion on the C++ committee's library reflector illuminated the &quot;illusion 
of portability&quot; problem, particularly in postings by PJ Plauger and Pete Becker.</p>

<p>Walter Landry provided much help illuminating symbolic link use cases for 
version 1.31.0.</p>

<h3>Version 1.34 (<a href="i18n.html">i18n</a>) acknowledgements</h3>

<p>So many people have contributed comments and bug reports that it isn't any 
longer possible to acknowledge them individually. That said, Peter Dimov and Rob 
Stewart need to be specially thanked for their many constructive criticisms and 
suggestions. Terence 
Wilson and Chris Frey contributed timing programs which helped illuminate 
performance issues.</p>

<h2><a name="Change-history">Change history</a></h2>

<h3>Version 1.37.0</h3>

<ul>
  <li>Doc fixes: Update release history, add tables of macros and deprecated 
  names.</li>
  <li>Bug fix: convenience.hpp didn't fully apply BOOST_FILESYSTEM_NO_DEPRECATED 
  to name changes.</li>
  <li>Bug fix: Ticket #1972 'remove' fixes.</li>
  <li>Bug fix: Restore deprecated basic_directory_entry names inadvertently 
  removed.</li>
  <li>Bug fix: Provide deprecated functions has_branch_path and has_leaf, 
  inadvertently omitted from 1.36.0</li>
  <li>Add workarounds for Codegear/Borland C++ Builder 2009.</li>
</ul>

<h3>Version 1.36.0 - August 14th, 2008</h3>

<ul>
  <li>Added stem(), extension(), and replace_extension() member functions to 
  basic_path, based on the basename(), extension(), and change_extension() 
  functions from convenience.hpp.</li>
  <li>Changed path.hpp function names:<ul>
    <li>leaf() -&gt; filename().</li>
    <li>has_leaf() -&gt; has_filename().</li>
    <li>branch_path() -&gt; parent_path().</li>
    <li>has_branch_path() -&gt; has_parent_path().</li>
    <li>remove_leaf() -&gt; remove_filename().</li>
  </ul>
  </li>
  <li>Changed operations.hpp function names:<ul>
    <li>is_regular() -&gt; is_regular_file().</li>
  </ul>
  </li>
  <li>Bug fix: Add path.cpp #include &lt;cwchar&gt;</li>
  <li>Cleared path.hpp gcc shadow warnings.</li>
</ul>

<h3>Version 1.35.0 - March 29th, 2008</h3>

<ul>
  <li>Diagnostics moved to the separate <a href="../../system/doc/index.html">
  Boost.System</a> library.</li>
  <li>current_path() function added to set the current directory path.</li>
  <li>Test coverage extended.</li>
  <li>A few minor implementation fixes.</li>
</ul>

<h3>Version 1.34.1 - July 24th, 2007</h3>

<h3><a href="i18n.html">Version 1.34.0</a> - May 12th, 2007</h3>

<ul>
  <li><a href="i18n.html#Internationalization">Internationalization</a>, provided by 
  class templates <i>basic_path</i>, <i>basic_filesystem_error</i>, and <i>
  basic_directory_iterator</i>.</li>
  <li><a href="i18n.html#Simplification">Simplification</a> of the path interface, 
  including elimination of distinction between native and generic formats, 
  and separation of name checking functionality from general path functionality.</li>
  <li><a href="i18n.html#Rationalization">Rationalization</a> of predicate 
  function design, including the addition of several new functions.</li>
  <li><a href="i18n.html#Preservation">Preservation</a> of existing user code whenever 
  possible. Deprecated features (<i>symbolic_link_exists()</i>, etc.) remain 
  available for legacy code.</li>
  <li>Clearer specification, by reference to [<a href="design.htm#POSIX-01">POSIX-01</a>], 
  the ISO/IEEE Single Unix Standard, with provisions for Windows and other 
  operating systems.</li>
  <li>New functions <a href="reference.html#Status-functions">status</a>,
  <a href="reference.html#Status-functions">symlink_status</a>,
  <a href="reference.html#Predicate-functions">is_file</a>,
  <a href="reference.html#Predicate-functions">is_symlink</a>,
  <a href="reference.html#Operations-functions">create_hard_link</a>, 
  <a href="reference.html#Operations-functions">create_symlink</a>, path member and non-member swap, path inserter, path 
  extractor, additional path relational and &quot;/&quot; operator overloads, additional 
  path member template functions taking iterator arguments.</li>
  <li><a href="i18n.html#More_efficient">More efficient operations</a> when iterating over directories.</li>
  <li>Separation within the implementation of the distinction between the native 
  operating system path syntax and API. This is important for CYGWIN users 
  because it allows them to build for either the Windows or POSIX API's.</li>
  <li>Numerous small implementation fixes.</li>
</ul>

<h3>Version 1.33.0 - August 11th, 2005</h3>

<ul>
  <li>Some small implementation fixes.</li>
</ul>

<h3>Version 1.32.0 - November 19th, 2004</h3>

<ul>
  <li><a href="reference.html#Attribute-functions">file_size()</a> function added.</li>
  <li>Class path <a href="reference.html#basic_path-non-member-functions">relational operators</a> added.</li>
  <li><a href="reference.html#Predicate-functions">equivalent()</a> function added.</li>
  <li><a href="reference.html#Operations-functions">create_directory()</a> no longer 
  throws if the directory already exists. A bool is returned, indicating that 
  the directory did not preexist. Similar changes made to
  <a href="reference.html#Convenience-functions">create_directories()</a>.</li>
  <li><a href="#Cgywin">Docs added</a> for users wishing Cygwin/POSIX behavior 
  on Windows.</li>
  <li>For POSIX, Large File Support (LSF) is enabled if available, such as on 
  Linux.</li>
  <li><a href="reference.html#initial_path">current_path()</a> and
  <a href="reference.html#initial_path">initial_path()</a> on POSIX now handle 
  very long paths correctly.</li>
</ul>

<h3>Version 1.31.0 - January 26th, 2004</h3>

<ul>
  <li>The object library can now be <a href="#Building">built</a> for either 
  static or dynamic (shared/dll) linking. </li>
  <li>Several added functions, including improved checking for directory and 
  file name portability. See <a href="portability_guide.htm#name_check­_functions">
  Name check functions</a>.</li>
  <li>Separation of canonical form and normalized form and a new path member 
  function normalize(). This changes behavior, 
  in that canonical form is now different, but eliminates a subtle
  <a href="design.htm#symbolic-link-use-case">bug</a> when symbolic links to 
  directories are present.</li>
</ul>

<h3>&nbsp;<br>
Version 1.30.0 - March 19th, 2003</h3>
<ul>
  <li>Initial official Boost version.</li>
</ul>

<hr>
<p>Revised
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->21 June, 2010<!--webbot bot="Timestamp" endspan i-checksum="19840" --></p>

<p>&copy; Copyright Beman Dawes, 2002-2005</p>
<p> Use, modification, and distribution are subject to the Boost Software 
License, Version 1.0. See <a href="http://www.boost.org/LICENSE_1_0.txt">
www.boost.org/LICENSE_1_0.txt</a></p>

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