Ethereal-dev: Re: [ethereal-dev] packet capture from switches and other RMON devices

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From: guy@xxxxxxxxxx (Guy Harris)
Date: Wed, 12 May 1999 17:29:12 -0700 (PDT)
> I was thinking of a filter saying "I only want the IP UDP datagrams from 
> remote capture device 10.1.9.65".

I.e., "capture only UDP datagrams from device 10.1.9.65" (that's a
capture filter), or "once I've captured datagrams from device 10.1.9.65,
show me only the UDP datagrams" (that's a display filter)?

And does that mean "capture/show me only packets from device 10.1.9.65
and, of those datagrams, capture/show me only UDP datagrams", or
"capture/show me packets from several devices, but, of those packets,
for the ones coming from device 10.1.9.65, capture/show me only UDP
datgrams"?

If the former, at least for captures, I'd expect that to be done by
separately specifying "capture only from 10.1.9.65" and "capture only
UDP datagrams"; the former would control which live-capture streams we
opened with Wiretap, and the latter would control the filter expression
we handed to Wiretape for that device.