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Wireshark-dev: Re: [Wireshark-dev] Subtree array purpose

From: Stephen Fisher <steve@xxxxxxxxxxxxxxxxxx>
Date: Fri, 29 Apr 2011 14:57:09 -0600
On Sat, Apr 30, 2011 at 12:50:33AM +0400, Max wrote:

> Can anybody please explain the purpose of subtree array (ett_...)?
> 
> I don't get why should i have several different etts in my dissector's 
> code, while there is no information assotiated with these integers.

My understanding is that Wireshark uses the subtree identifier when you 
move between packets to know which subtrees to leave open if you already 
had it open.  The idea is that the same information (same subtree) in 
each packet is shown at the same time.