Making own Simple Port Scanner

Code in Perl::

use IO::Socket;
$port = 19;
while ($port < 26){
$spy = new IO::Socket::INET (PeerAddr => '127.0.0.1',
PeerPort => $port,
Proto => 'tcp');
if ($spy){
close $spy;
print "$port -open\n";
$port = $port + 1;
}
else{
print "$port -closed\n";
$port = $port + 1;
}
}

Code in Ruby:: 

require 'socket'
require 'timeout'

ports = 19..26
ports.each do |spy|
begin
Timeout::timeout(10){TCPSocket.new("127.0.0.1", spy)}
rescue
puts "closed : #{spy}"
else
puts "open : #{spy}"
end
end

Code in Java::

import java.net.*;
import java.io.IOException;

public class javaps {
public static void main(String[] args)
{
String remote = "172.16.0.1";
for (int port = 19; port <= 26; port++) {
try {
Socket s = new Socket(remote, port);
System.out.println("The port " + port + " of " + remote + " is open");
s.close();
}
catch (IOException ex) {
System.out.println("The port " + port + " of " + remote + " is closed");
}}}}

Simplest way to make a port scanner..

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