내부 IP 주소 알아내는 함수

function My_IP : String;

var
  WSAData: TWSAData;
  HostName, IPAddress: String;
  HostEnt: PHostEnt;
begin
  WSAStartup(2, WSAData);

  SetLength(HostName, 255);

  GetHostname(PChar(HostName), 255);

  SetLength(HostName, StrLen(PChar(HostName)));

  HostEnt := GetHostByName(PChar(HostName));

  with HostEnt^ do

  IPAddress := Format('%d.%d.%d.%d',[Byte(h_addr^[0]), Byte(h_addr^[1]),

  Byte(h_addr^[2]), Byte(h_addr^[3])]);

  WSACleanup;

  Result := IPAddress;
end;

uese절에 Winsock 추가