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Re: Reliability issues with BPF

Darren Reed <> writes:

> For example, if I start tcpdump in the background
> and then run an ipv6 ping generating 2000 byte
> packets with a command like "ping6 -nc3 -s2000 fec0::1",
> the ping ends successfully but terminating the
> tcpdump may show as few as 8 packets rather than
> 12. 3 packets going in each direction (echo plus
> echo reply) makes 6, doubled for fragments gives
> 12. I can't for the life of me think why this
> should be.

Are you waiting long enough?  IIRC there are two buffers, and read
returns when they get full or timeout, and I don't know that ^C causes
the final read.

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