#Server.pl
#!/usr/local/bin/perl
use strict;
use warnings;
use IO::Socket;

my $server = IO::Socket::INET->new(
   LocalPort=> 1121,
   Type=>SOCK_STREAM,
   Reuse=>1,
   Listen=>1
   )or die ("Could not create server");

while(my $client=$server->accept()){
         my $child_pid;
         unless(defined ($child_pid=fork())){die"can not fork\n";}
         if(defined($child_pid)){
                        while(my $line = <$client>){
                                 print "CLIENT says:$line\n";
                                 }
                        }else{
                              while(my $line = <>){
                                          print $client "$line\n";
                                          }
                              }
         }

close($server);
<>;

##</code><code>##

#Client.pl
use strict;
use warnings;
use IO::Socket;

my $socket = IO::Socket::INET->new(
   PeerAddr =>"192.168.1.100",
   PeerPort =>1121,
   Proto =>"tcp",
   Type =>SOCK_STREAM,
   )or die ("Could not create client");
   
#fork the process
my $child_pid;
unless (defined($child_pid=fork())){die("can not fork")};
if(defined($child_pid)){
               while(my $line = <STDIN>){
                           print $socket $line;
                           }
               }else{
                     while(my $line = <$socket>){
                                 print "SERVER says: $line\n";
                                 }
                     }
close($socket);
<>;

##</code><code>##

if(defined($child_pid)){}
if($child_pid){}
if($child_pid==1){}
if($child_pid==0){}

##</code><code>##