Ethereal-users: Re: [Ethereal-users] Custom 802.1q tag type

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From: Guy Harris <guy@xxxxxxxxxxxx>
Date: Fri, 31 Oct 2003 10:18:03 -0800
On Oct 31, 2003, at 4:15 AM, Adalberto Lins wrote:

Can you point me to the reference on how I can write a dissector?
Various of the README files in the "doc" directory of the Ethereal 
source.
The 0x9100 headers are identical to the 0x8100!
If by "identical" you mean that Ethernet packets with a type of 0x9100 
have the same VLAN header as Ethernet packets with a type of 0x8100, 
i.e. that those packets should be dissected in *exactly* the same way 
as 0x8100 802.1q packets, you don't write a dissector - you just add 
the line
	dissector_add("ethertype", 0x9100, vlan_handle);

to the end of the "proto_reg_handoff_vlan()" routine in "packet-vlan.c".