show all IP's on the network that listen to specific portnr

[Glenndevos]

Many thanks. I placed the code in a loop to check a certain range with a progressbar indicating the progress but found that for some IP adresses, there's a (too) big delay, takes approx. 4-5 seconds for an IP-adress that is not connected on the network. If I do a netstat on the doscommand prompt, that takes 0.5 seconds ... any option to speed things up ?

Thanks !
Glenn

Delphi-Quellcode:

for i := offset to last do
  begin
  progress := progress + progressstep;
  progressbar1.Position := round(progress);

  adrestocheck := IPA1.text + '.' + IPA2.text + '.' + IPA3.text + '.'+inttostr(i);

  WSAStartup($0101,WSAData);

  if checkportopen(adrestocheck,6363) then
    begin
      memo1.Lines.Add(adrestocheck);

    end
    else
    begin
      label1.caption :=('not');
    end;
  WSACleanUp;
  end;