sub syn_packets {
    my ($user_data, $header, $packet) = @_;

    #   Strip ethernet encapsulation of captured packet 

    my $ether_data = NetPacket::Ethernet::strip($packet);

    #   Decode contents of TCP/IP packet contained within 
    #   captured ethernet packet

    my $ip = NetPacket::IP->decode($ether_data);
    my $tcp = NetPacket::TCP->decode($ip->{'data'});

    #   Print all out where its coming from and where its 
    #   going to!

    print
        $ip->{'src_ip'}, ":", $tcp->{'src_port'}, " -> ",
        $ip->{'dest_ip'}, ":", $tcp->{'dest_port'}, "\n";
}
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