Boost C++ Libraries

...one of the most highly regarded and expertly designed C++ library projects in the world. Herb Sutter and Andrei Alexandrescu, C++ Coding Standards

libs/filesystem/example/tut3.cpp

//  filesystem tut3.cpp  ---------------------------------------------------------------//

//  Copyright Beman Dawes 2009

//  Distributed under the Boost Software License, Version 1.0.
//  See http://www.boost.org/LICENSE_1_0.txt

//  Library home page: http://www.boost.org/libs/filesystem

#include <iostream>
#include <iterator>
#include <algorithm>
#include <boost/filesystem.hpp>
using namespace std;
using namespace boost::filesystem;

int main(int argc, char* argv[])
{
  if (argc < 2)
  {
    cout << "Usage: tut3 path\n";
    return 1;
  }

  path p (argv[1]);   // p reads clearer than argv[1] in the following code

  try
  {
    if (exists(p))    // does p actually exist?
    {
      if (is_regular_file(p))        // is p a regular file?
        cout << p << " size is " << file_size(p) << '\n';

      else if (is_directory(p))      // is p a directory?
      {
        cout << p << " is a directory containing:\n";

        copy(directory_iterator(p), directory_iterator(),  // directory_iterator::value_type
          ostream_iterator<directory_entry>(cout, "\n"));  // is directory_entry, which is
                                                           // converted to a path by the
                                                           // path stream inserter
      }
      else
        cout << p << " exists, but is neither a regular file nor a directory\n";
    }
    else
      cout << p << " does not exist\n";
  }

  catch (const filesystem_error& ex)
  {
    cout << ex.what() << '\n';
  }

  return 0;
}