"Paul" wrote

| There is a stark difference, between how Explorer.exe
| works when dealing with files, and how a shell-level
| FindNext works.
|
| I can do "dir" in a Command Prompt window, and easily list
| 8 million files in the window. They're sorted in alphabetical
| order in three columns. That means the command knew pretty
| close to the beginning of the output, what it had to do.
|

Explorer is using FindFirstFile/FindNextFile and
may even be using something better under the
surface -- Microsoft's private stock. But it also
has to deal with showing icons, calculating time
remaining with deletes, managing shell extensions,
etc. In other words, the API is just dealing with
the file system. Explorer is primarily GUI functionality.
And it's still tied into IE.

If you look at it in Depends or a similar program
you can see that kernel and ntdll are only a small
part of what Explorer is dealing with It's loading
wininet (IE) to parse URLs, uxtheme for the GUI
theme, user32 for drawing and tracking down user
display preferences, gdi for display, some unnamed
functions from shdocvw (IE again).... Plus there are
things like ole, browseui.dll and version.dll for
collecting file info, properties, default icon, media
info, etc. If you're going to deal with files in a folder
in the Windows GUI, all of that comes into play.