use strict; 
use IO::Socket; 
use threads; 
use warnings; 
 
print "Enter port: "; 
chomp(my $port = <STDIN>); 
 
my $socket = new IO::Socket::INET ( 
			LocalHost => 'localhost', 
			LocalPort => $port, 
			Proto	  => 'tcp', 
			Reuse 	  => 1, 
			Listen 	  => 5, 
			) 
or die "Error $!\n"; 
 
print "Server $0 is now active.\n"; 
 
while (1) { 
		my $new_client = $socket->accept(); 
		threads->new(\&client_sub, $new_client); 
} 
 
sub client_sub { 
	my ($client) = @_; 
	my $buffer = undef; 
 
	eval { 
 
	local $SIG{ALRM} = sub { die "alarm\n" }; 
	alarm 4; 
	 
	chomp(my $first = <$client>); 
	print $first; 
	chomp(my $second = <$client>); 
	print $second; 
 
	alarm 0; 
 
	# some text processing, final string ends in $_ 
	 
	print $client $_; 
	 
	}; 
 
	if ($@) { 
		print $client "Timeout.\n" if $@ eq "alarm\n"; 
	} else { 
		die "DIED $!\n"; 
	}  
 
	close $client; 
}