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            "Delphi X-Files" <www.DelphiXFiles.narod.ru>"
                "Определение серийного номера диска"
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procedure TForm1.Button1Click(Sender: TObject);
var
  SerialNum: PDword;
  A, B     : Dword;
  Buffer   : Array [0..255] of Char;
begin
  New(SerialNum);
  if GetVolumeInformation('C:\', Buffer, SizeOf(Buffer),
                          SerialNum, A, B, Nil,0) then
    Label1.Caption := IntToStr(SerialNum^);
  Dispose(SerialNum);
end;
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