Vhd_format.Elementtype 'a t = [ | `Copy of 'a * int64 * int64Copy (t, offset, len) copies len sectors from sector offset from the file t
| `Sectors of Cstruct.ta new sector (e.g. for metadata)
*)| `Empty of int64empty space in sectors
*) ]A disk can be streamed as a sequence of elements
val to_string : 'a t -> stringval len : 'a t -> int64len t is the length of t in sectors