binmode $sock;
my $header = 
"GET / HTTP/1.1\r\n" . 
"Host: localhost\r\n" .
"Upgrade: websocket\r\n" .
"Connection: Upgrade\r\n" .
"Sec-WebSocket-Key: x3JJHMbDL1EzLkh9GBhXDw==\r\n" .
"Sec-WebSocket-Protocol: chat, superchat\r\n" .
"Sec-WebSocket-Version: 13\r\n" .
"Origin: https://cavac.at\r\n" .
"\r\n";

syswrite($sock, $header);
my $line = "";
while(1) {
    my $char;
    sysread($sock, $char, 1);
    if(defined($char) && length($char)) {
        if($char eq "\r") {
            next;
        } elsif($char eq "\n") {
            if($line eq "") {
                # end of header
                last;
            } else {
                $line = "";
            }
        } else {
            $line .= $char;
        }
    }
}
    
my $frame = Protocol::WebSocket::Frame->new(max_payload_size => 500 * 1024 * 1024, masked => 1);