use 5.010;
use strict;
use warnings;

use Socket;

socket my $sock, PF_INET, SOCK_STREAM, getprotobyname("tcp");
bind $sock, sockaddr_in(7777, INADDR_ANY);
listen $sock, 0;
while (accept my $cli, $sock) {
    sleep 60;
}

##</code><code>##

nc localhost 7777

##</code><code>##

$ sudo netstat -tanp | grep -v LISTEN | grep 7777
tcp        0      0 127.0.0.1:7777          127.0.0.1:44394         SYN_RECV    -
tcp        0      0 127.0.0.1:7777          127.0.0.1:44396         SYN_RECV    -
tcp        0      0 127.0.0.1:44394         127.0.0.1:7777          ESTABLISHED 4384/nc
tcp        0      0 127.0.0.1:7777          127.0.0.1:44390         ESTABLISHED 3992/perl
tcp        0      0 127.0.0.1:44390         127.0.0.1:7777          ESTABLISHED 4382/nc
tcp        0      0 127.0.0.1:7777          127.0.0.1:44392         ESTABLISHED -
tcp        0      0 127.0.0.1:44396         127.0.0.1:7777          ESTABLISHED 4385/nc
tcp        0      0 127.0.0.1:44392         127.0.0.1:7777          ESTABLISHED 4383/nc