Fetch network in/out statistics?

[Jamie]

I've seen this before, but I can't remember the name of the command.

Basically, I want to fetch the in/out bytes of a given interface over
a sampling time.

something like: fetch-stats re0 lo0

    in      out
re0 1205124 5012364
lo0 12348   54212
... ......  .......

(Would be better if it gave me the stats for each IP number assigned
to the interface)

I tried trafd and some other stuff, but trafd gives me way too much
information, and I don't want my network monitor to be the "main"
application running... I just want something I can easily feed into
mrtg (w/out snmp or, ideally, any daemons besides cron)

Can you remember the name of the command that does that?

Jamie
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