elsif($self->param('downconfig')){
                #$self->dd($self->{SHOPCONFIG});
                $self->header(
                        'Content-Type' => 'application/octet-stream',
                        'Content-Disposition' => "Attachment; filename=shopcfg.$self->{LANG}",
                );
                use bytes;
                foreach my $k(keys %{$self->{SHOPCONFIG}}){
                        my $klen = length $k;
                        my $vlen = length $self->{SHOPCONFIG}{$k}; 
                        #die "$self->{SHOPCONFIG}{$k} $vlen";
                        $self->{CONTENT} .= pack("N",$klen).$k.pack("N",$vlen).$self->{SHOPCONFIG}{$k};
                }
        }
        elsif($self->param('upload')){
                my $fh = $self->param('upfile') or die "Keine Datei angegeben\n";
                use bytes;
                my $buffer = '';
                my %cfg = ();
                while(  read($fh, $buffer, 4) ){
                        my $klen = unpack "N", $buffer;
                        read($fh, $buffer, $klen); # key in buffer
                        my $key = $buffer;
                        read($fh, $buffer, 4);
                        my $vlen = unpack "N", $buffer;
                        read($fh, $buffer, $vlen); # value in buffer
                        $cfg{$key} = $buffer;
                }
                $self->{SHOPCONFIG} = \%cfg;
                tied($self->{SHOPCONFIG})->write or die $@;
                
                $self->header(
                        Status => "301 Moved",
                        Location => $self->{URL},
                );
        }

my @octets = unpack("C11", $data);

my $s = pack("C11", (65..75)); 
my @test = unpack("C11", $s);
print join(' : ', map {chr()} @test);

A : B : C : D : E : F : G : H : I : J : K

my $packet_length = 11;
my $unpack_str = 'A' x $packet_length;
my $s = pack("C11", (65..75));

print join(' : ', unpack($unpack_str, $s));

my $data = pack("C11", (65..75));
my $str = unpack("A11", $data);