Re: capturing on both interfaces simultaneously

[abhinav narain <abhinavnarain10 () gmail com>]

It sniffs for beacons by using bpf filter and keeps a per AP record of
packet count etc in a table.

Is poll() better than select ?

I can only see A,B,G in beacons in tcpdump code, reading the radiotap
header..
How can I infer an AP is N ?


On Sun, Dec 11, 2011 at 2:35 PM, Guy Harris <guy () alum mit edu> wrote:

> On Dec 11, 2011, at 11:17 AM, abhinav narain wrote:
>
> > > What is "it"?  Your program?  Or just *some* program?
> > Its the return statement of perror.
>
> Presumably you were calling perror() because some call returned -1; what
> call was that?  If something keeps returning -1 because, for example, it's
> a read from a non-blocking file descriptor on which no data is available to
> read, your program is going to be chewing up CPU looping.
>
> > It works fine now.
> > But how do I know, how much packets is my program dropping?
> > using pcap_stats ?
>
> Yes.
>
> > I already have 15% RAM being eaten by the program, so I can't actually
> > increase the buffer size to save packets in between select switches.
>
> What is your program doing with the packets when it captures them?-
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