GetMACAddress

uses
  NB30;

function GetMACAddress: string;

  function GetAdapterInfo(Lana: AnsiChar): string;
  var
    Adapter: TAdapterStatus;
    NCB: TNCB;
  begin
    FillChar(NCB, SizeOf(NCB), 0);
    NCB.ncb_command := Char(NCBRESET);
    NCB.ncb_lana_num := Lana;
    if Netbios(@NCB) <> Char(NRC_GOODRET) then
    begin
      Result := 'mac not found';
      Exit;
    end;
    FillChar(NCB, SizeOf(NCB), 0);
    NCB.ncb_command := Char(NCBASTAT);
    NCB.ncb_lana_num := Lana;
    NCB.ncb_callname := '*';
    FillChar(Adapter, SizeOf(Adapter), 0);
    NCB.ncb_buffer := @Adapter;
    NCB.ncb_length := SizeOf(Adapter);
    if Netbios(@NCB) <> Char(NRC_GOODRET) then
    begin
      Result := 'mac not found';
      Exit;
    end;
    Result := IntToHex(Byte(Adapter.adapter_address[0]), 2) + '-' + IntToHex(Byte
      (Adapter.adapter_address[1]), 2) + '-' + IntToHex(Byte(Adapter.adapter_address
      [2]), 2) + '-' + IntToHex(Byte(Adapter.adapter_address[3]), 2) + '-' +
      IntToHex(Byte(Adapter.adapter_address[4]), 2) + '-' + IntToHex(Byte(Adapter.adapter_address
      [5]), 2);
  end;

var
  AdapterList: TLanaEnum;
  NCB: TNCB;
begin
  FillChar(NCB, SizeOf(NCB), 0);
  NCB.ncb_command := Char(NCBENUM);
  NCB.ncb_buffer := @AdapterList;
  NCB.ncb_length := SizeOf(AdapterList);
  Netbios(@NCB);
  if Byte(AdapterList.length) > 0 then
    Result := GetAdapterInfo(AdapterList.lana[0])
  else
    Result := 'mac not found';
end;