while(<$client>)
     { print $_;
       print $client "Username $user Pass $pass";}

##</code><code>##

  print $client "Username $user Pass $pass";
  while(<$client>)
  {
    print $_;
    <STDIN>; #read input from user (changes $_!)
    print $client $_;
  }

##</code><code>##

  $host = $ARGV[2]; #or whatever it is in your ARGV
  $port = $ARGV[4];

  my $client = IO::Socket::INET->new(
        PeerAddr => $host,
        PeerPort => $port,