VM undo disks mode: PUD_DISABLE_UNDO_DISKS : disbale undo disks PUD_REVERSE_CHANGES : at stopping VM revert all disk changes PUD_COMMIT_CHANGES : at stopping VM apply all disk changes PUD_PROMPT_BEHAVIOUR : ask user which mode reverse or commit will be applied

typedef enum _PRL_UNDO_DISKS_MODE {
  PUD_DISABLE_UNDO_DISKS = 0,
  PUD_REVERSE_CHANGES = 1,
  PUD_COMMIT_CHANGES = 2,
  PUD_PROMPT_BEHAVIOUR = 3
} PRL_UNDO_DISKS_MODE;