#!/usr/bin/env perl

use strict;
use warnings;

use threads;
use Thread::Queue;
use IO::Socket;

my $nthreads = 20;

my $in_file2 = 'rang.txt';

my $work_q   = Thread::Queue->new;
my $result_q = Thread::Queue->new;

sub ip_checker {
    while ( my $ip = $work_q->dequeue ) {
        chomp($ip);
        $host = IO::Socket::INET->new(
            PeerAddr => $ip,
            PeerPort => 80,
            proto    => 'tcp',
            Timeout  => 1
        );
        if ( defined $host ) {
            $result_q->enqueue($ip);
        }
    }
}

sub file_writer {
    open( my $output_fh, ">>", "port.txt" ) or die $!;
    while ( my $ip = $result_q->dequeue ) {
        print {$output_fh} "$ip\n";
    }
    close($output_fh);
}


for ( 1 .. $nthreads ) {
    push( @workers, threads->create( \&ip_checker ) );
}
my $writer = threads->create( \&file_writer );

open( my $dat, "<", $in_file2 ) or die $!;
$work_q->enqueue(<$dat>);
close($dat);
$work_q->end;

foreach my $thr (@workers) {
    $thr->join();
}

$result_q->end;
$writer->join();