System_WinDrives uses win32 api calls to get a list of all installed roots ("Drives") on the current Windows operating system (The folders "A:\" until "Z:\").
Additional to the list of drives, detail information like the name and the drive type (network, harddisk, removable etc) is given.
The win32 api functions are used to access the Windows application programming interface. This means that the extension php_w32api.dll on PHP4 and php_ffi.dll on PHP5 have to be installed to use all functions. If no dll is available, the drives are guessed, but drive types and drive names can't be determined.