FSCTL_HANDLE
hFile directs routing. pszRoute must be a null pointer (0L).
The file-system driver associated with the handle receives the request.
FSCTL_PATHNAME
pszRoute refers to a path name that directs routing. hFile must
be -1. The file-system driver associated with the drive that the path name
refers to at the time of the request receives the request. The path name
need not refer to a file or directory that actually exists, only to a drive.
A relative path name may be used; it is processed like any other path name.
FSCTL_FSDNAME
pszRoute refers to a file-system driver name that directs routing.
hFile must be -1. The named file-system driver receives the request.