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Ethereal-users: Re: [Ethereal-users] Unclear statement

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From: Guy Harris <gharris@xxxxxxxxx>
Date: Sat, 14 Jul 2001 12:45:43 -0700
On Sat, Jul 14, 2001 at 11:56:34AM -0500, Jeff Foster wrote:
> > "Capture files can me programmatically edited or converted via
> command-line
> > switches to the "editcap" program."
> 
> Change the "me" to "be" and it comes closer to making sense. It means that
> you can use the "editcap" program to filter

What sort of filtering are you referring to?  (If you mean "apply a
display filter, so that only those packets in the input capture file
that match the display filter will be written to the output capture
file, there's already a program to do that, called "tethereal":

	tethereal -r input_file -w output_file filter

If you want to use a capture filter instead, there's a program to do
that, also, called "tcpdump".)

> or otherwise change a capture file.

To what sort of changes are you referring?  By "programmatically" are you
implying that there should be a language that can be used to specify the
transformations to be performed, with editcap including an interpreter
for that language?  (This is not a rhetorical question, i.e. I'm not
saying that it would be a bad idea to have such a language.)

> In addition ethereal has enough functional to allow you to write a
> program, using libraries from ethereal, that can manipulate capture files.

I.e., export Wiretap and libethereal+dissectors as a library with a
specified API, so that manipulations not done by Ethereal or editcap
(or, if editcap has a language of the sort described earlier, not doable
within that language) can be done by writing a program using those
libraries?