Seek position inside a directory. The precise meaning of the Name and Index values are entirely
up to an implementation; it could indicate the next entry to be returned or the last entry
returned; the type should be considered to be opaque to the client. There are some
implementations that return entries in alphabetical order, but they are not required to do so.
The Start value indicates the first entry should be returned and the End value indicates no more
entries should be returned.