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function GetDiskLabel(Drv: String): String;
var
  Buff: array [0..254] of Char;
  r: UINT;
begin
  FillChar(Buff, SizeOf(Buff), 0);
  GetVolumeInformation(PChar(Drv), Buff, SizeOf(Buff), nil, r, r, nil, 0);
  Result := Buff;
end;