Wireshark · Ethereal-dev: Re: [Ethereal-dev] referencing specific tcp protocol data

[Phil Williams <csypbw@xxxxxxxxxxxxxxxx>]

>
> A "proto_node" contains a "field_info" pointer; a "field_info", as
> defined in <epan/proto.h>, contains:
>
> 	a "header_field_info" pointer;
>
> 	an "fvalue_t" pointer;
>
> 	a bunch of other information.
>
> The "header_field_info" structure points to a structure that represents
> an attribute; the "fvalue_t" pointer points to a structure that
> represents a value.
>
> The only problem is that the attributes are identified by
> "header_field_info" pointers rather than by name.  If we provided
> routines to look up "header_field_info" structures by name, that
> probably wouldn't be a problem.
>

Well in this case, can I not get access to the data I require by looking
up using header_field_info pointers, rather than names?
With the tree being (attribute, value), is the attribute (eg for TCP
header length) always the same? If so wouldn't it be possible to
get access to the data that I require?  Though this is less elegant than
using the actual names should it be feasible?
If so, what values / names do these header_field_info pointers take?

Thanks

-- 
Phil Williams