WinXP API CreateFile() function

I've some question about CreateFile() function, I found the information from http://msdn.microsoft.com/library/default.asp?url=/library/en-us/fileio/fs/createfile.asp in part of Physical Disks and Volumes . It has some requirement for this function is The caller must have administrative privileges

who know that how can i use this function with user privileges?

any help is appreciate

thanks