function DiskSpaceInfo(const Drive: string; out AvailBytes, TotalBytes,
  FreeBytes: Int64): Boolean;
begin
  // We use GetDiskFreeSpaceEx from SysUtils since it deals with OSs that do not
  // support the Windows GetDiskFreeSpaceEx API call
  Result := SysUtils.GetDiskFreeSpaceEx(
    PChar(Drive), AvailBytes, TotalBytes, @FreeBytes
  );
  if not Result then
  begin
    AvailBytes := 0;
    TotalBytes := 0;
    FreeBytes := 0;
  end;
end;
//delphi/2195