gistfile1.pl

#!/usr/bin/perl
use strict;
use warnings;
use Mojo::IOLoop;

my ($ip, $port, $status);

Mojo::IOLoop->client({ port => $port, address => $ip } => sub {
  my ($loop, $error, $stream) = (@_);
  
  if(defined($error)) {
    print 'KO', "\n";
  } else {
    print 'OK', "\n";
  }
});

Mojo::IOLoop->start unless Mojo::IOLoop->is_running;