use strict;
use IO::Socket::INET;

my $ts = time(); # current time
my $last = $ts;  # process the infinite loop each second only, no milliseconds needed
my %socklist = (); # hash table of sockets
my $bit = '';

# connect to the IRC server
my $socket = &open_socket("tcp", "ircserver.com", 6667, 3);

sub open_socket {
  my ($proto, $host, $port, $timeout) = (shift, shift, shift, shift);

  my $socket = IO::Socket::INET->new(
    Proto => $proto,
    PeerAddr => $host,
    PeerPort => $port,
    Timeout => $timeout
  );

  if (!$socket) { return(0); }
  return($socket);
}

if (!$socket) { die("can't connect"); }

&add_socket($socket, "IRC");

sub add_socket {
  my ($socket, $type) = (shift, shift);

  $socket->autoflush(1);

  $socklist{$socket}{'sock'} = $socket;
  $socklist{$socket}{'type'} = $type;
  $socklist{$socket}{'fileno'} = $socket->fileno();
  $socklist{$socket}{'time'} = $ts;

  vec($bit, $socklist{$socket}{'fileno'}, 1) = 1;

  return(0);
}

print $socket "USER zxf sdf sdf sdf\n";
print $socket "NICK sdfsdfg\n";

sub loop_socket {
  my $rin = $bit; $rin =~ /[^\0]/ || next;
  my $idx = select($rin, undef, undef, 1);
  my $buffer = "";

  $idx || next;
  $idx > 0 || die($!);

  my %list = %socklist; # work with a copy

  while ($idx && (my ($socket, $value) = each(%list))) {
    $socket = $value->{'sock'};

    if (vec($rin, $value->{'fileno'}, 1)) { $buffer = <$socket>; print STDOUT "IRC: $buffer"; }
  }

  return(0);
}

for (;;) {
  &loop_socket();
}