Re: 32bit libpcap failure on Linux-ppc64 machine

[Zvika Meiseles <zvika.meiseles () gmail com>]

Guy Harris <guy <at> alum.mit.edu> writes:

> You probably need a newer kernel.  The original ring buffer mechanism didn't
work if the userland code isn't
> the same bit width as the kernel code, because "struct tpacket_hdr" has an
"unsigned long" member, which
> means the structure's layout differs between 32-bit and 64-bit.  Somewhere
between 2.6.18.2 and
> 2.6.27.9, a second structure, all of whose fields are __u32 or __u16 and thus
the same in 32-bit and 64-bit
> mode, was added, so that users of the ring buffer mechanism can either get the
old structure by default or
> can select the new header.
>
> If the new header is available, libpcap will use it.

Ok, thanks.
I just checked all the environments that "work" (as per QA), and sure enough,
they don't... The same OS on an Intel machine fails with the same problem.
I then compared the header files on those machines and my development machine
and saw the difference, like you said.

Great help, thank you very much.

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