external fsck : t -> string -> string -> int = "ocaml_guestfs_fsck"
external zero : t -> string -> unit = "ocaml_guestfs_zero"
external grub_install : t -> string -> string -> unit = "ocaml_guestfs_grub_install"
+external cp : t -> string -> string -> unit = "ocaml_guestfs_cp"
+external cp_a : t -> string -> string -> unit = "ocaml_guestfs_cp_a"
+external mv : t -> string -> string -> unit = "ocaml_guestfs_mv"