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

my $CRLF = chr(13).chr(10);

use constant SERVER_PORT => 40411;
use constant KEEPALIVESEC => 10;


my $sock = IO::Socket::INET->new(PeerHost => 'localhost', PeerPort => SERVER_PORT, Proto => 'tcp');

if($sock->connected)
{
  print "KARAMBA\n";

  local $SIG{ALRM} = sub {
     if($sock->connected)
     {
        $sock->write("E$CRLF", 3);
        $sock->getline();
        alarm KEEPALIVESEC;
     }
  }
  alarm KEEPALIVESEC;

  my $request = "";
  my $response = "";
  while(lc($request) ne "quit" and lc($response) ne "quit")
  {      
     print "Eingabe: \n";
     $request = <STDIN>;
     
     alarm KEEPALIVESEC; # alarm reset (hoffentlich; kenn ich damit gar nicht aus)

     chomp $request;

     $sock->write("$request$CRLF", length($request)+2);
     print "YOU wrote: [$request]\n";
     $response = $sock->getline();
     chomp $response;
     $response =~ s!$CRLF$!!g; # to be sure
     print "SERVER wrote: [$response]\n";
  }
  alarm 0;               # race condition protection
}