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    <p>Interestingly, I had the same idea some time ago. Here's what I wrote up:</p> <pre><code>#define WIN32_LEAN_AND_MEAN #include &lt;windows.h&gt; #include &lt;string&gt; #include &lt;iterator&gt; #include &lt;exception&gt; #ifndef DIR_ITERATOR_H_INC #define DIR_ITERATOR_H_INC class dir_iterator #if (!defined(_MSC_VER)) || (_MSC_VER &gt; 1200) : public std::iterator&lt;std::input_iterator_tag, std::string, int, std::string *, std::string &amp;&gt; #endif { mutable HANDLE it; std::string mask; std::string path; WIN32_FIND_DATA data; bool done; DWORD require; DWORD prohibit; public: WIN32_FIND_DATA operator*() { return data; } dir_iterator(dir_iterator const &amp;other) : it(other.it), mask(other.mask), path(other.path), data(other.data), done(other.done), require(other.require), prohibit(other.prohibit) { // Transfer the handle instead of just copying it. other.it=INVALID_HANDLE_VALUE; } dir_iterator(std::string const &amp;s, DWORD must = 0, DWORD cant = FILE_ATTRIBUTE_DIRECTORY) : mask(s), require(must), prohibit(cant &amp; ~must), done(false), it(INVALID_HANDLE_VALUE) // To fix bug spotted by Billy ONeal. { int pos; if (std::string::npos != (pos=mask.find_last_of("\\/"))) path = std::string(mask, 0, pos+1); it = FindFirstFile(mask.c_str(), &amp;data); if (it == INVALID_HANDLE_VALUE) throw std::invalid_argument("Directory Inaccessible"); while (!(((data.dwFileAttributes &amp; require) == require) &amp;&amp; ((data.dwFileAttributes &amp; prohibit) == 0))) { if (done = (FindNextFile(it, &amp;data)==0)) break; } } dir_iterator() : done(true) {} dir_iterator &amp;operator++() { do { if (done = (FindNextFile(it, &amp;data)==0)) break; } while (!(((data.dwFileAttributes &amp; require) == require) &amp;&amp; (data.dwFileAttributes &amp; prohibit) == 0)); return *this; } bool operator!=(dir_iterator const &amp;other) { return done != other.done; } bool operator==(dir_iterator const &amp;other) { return done == other.done; } ~dir_iterator() { // The rest of the bug fix -- only close handle if it's open. if (it!=INVALID_HANDLE_VALUE) FindClose(it); } }; #endif </code></pre> <p>And a quick demonstration of it:</p> <pre><code>#include "dir_iterator.h" #include &lt;iostream&gt; #include &lt;algorithm&gt; namespace std { std::ostream &amp;operator&lt;&lt;(std::ostream &amp;os, WIN32_FIND_DATA const &amp;d) { return os &lt;&lt; d.cFileName; } } int main() { std::copy(dir_iterator("*"), dir_iterator(), std::ostream_iterator&lt;WIN32_FIND_DATA&gt;(std::cout, "\n")); std::cout &lt;&lt; "\nDirectories:\n"; std::copy(dir_iterator("*", FILE_ATTRIBUTE_DIRECTORY), dir_iterator(), std::ostream_iterator&lt;WIN32_FIND_DATA&gt;(std::cout, "\n")); return 0; } </code></pre>
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    1. POHow might I wrap the FindXFile-style APIs to the STL-style Iterator Pattern in C++?
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    1. CO+1 -- though correct me if I'm wrong here -- doesn't that call FindClose() on garbage data when the default constructed iterator is destructed?
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    2. CO@Billy:now that you mention it, yes, I think it does. I'll have to fix that. One of the benefits of posting code is getting a bug caught now and again -- thank you.
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    3. CO@Jerry Coffin: One more bug -- if the iterator is copied then FindClose() will be called twice on the same handle. Just don't call STL algorithms on this LOL!. Giving you the checkmark for the demonstration.
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