id	summary	reporter	owner	description	type	status	milestone	component	version	severity	resolution	keywords	cc
4494	recursive_directory_iterator throws unexpectedly in the non-throw mode	ttan@…	Beman Dawes	"In boost::filesystem v3, while it’s possible to choose a no-throw version of recursive_directory_iterator by passing an boost::system::error_code object to its constructor, like this:
                                  boost::system::error_code m_ec;
                                  for ( recursive_directory_iterator itr(root, m_ec), end_itr; itr != end_itr; ++itr)

However, because in the implementation of the recursive_directory_iterator::increment(),  directory_iterator is always constructed with the throw version, it would cause exception throws during the for-loop while accessing folders like \System Volume Information on Windows: 
    void increment()
    { 
      BOOST_ASSERT(m_imp.get() && ""increment of end recursive_directory_iterator"");
      m_imp->increment(0);
      if (m_imp->m_stack.empty()) m_imp.reset(); // done, so make end iterator
}

Where m_imp is an object of recur_dir_itr_imp:
    void recur_dir_itr_imp::increment(system::error_code* ec)
    // ec == 0 means throw on error
{
…
}

As it’s not possible to catch this exception within the for-loop and continue the loop, it greatly limits the use of recursive_directory_iterator. 
With a rough check, V2 does not seem to have this problem. it's preferred that the directory_iterator to behave the same as recursive_directory_iterator in this case.
"	Feature Requests	assigned	Boost 1.44.0	filesystem	Boost Development Trunk	Problem		filesystem v3 throw