Re: pcap_inject() an Ethernet's FCS

[Aaron Turner <synfinatic () gmail com>]

On Thu, Jan 14, 2010 at 5:50 PM, Guy Harris <guy () alum mit edu> wrote:
> On Jan 14, 2010, at 5:45 PM, David Crowcroft wrote:
>
> > It looks like you either forgot to attach the files, or majordomo
> > stripped them off your e-mail.
>
> The latter.
>
> > (plese resend them off-list to me, if necessary).
>
> Will do.
>
> > > > For instance, do I need to calculate the FCS in the Ethernet frames I
> > > > send?
> > >
> > > *Probably* not, at least in most cases.
> >
> > Is there a portable way of deciding whether I *need* to do it?
>
> No.  I don't even know whether there are any platforms where you do.

While I can't say for certain such platforms don't exist, I can say I
haven't seen the need to do so any platform in the last 10 years-
including embedded systems used on the ISS (as in International Space
Station).   So unless you're coding for something really really
obscure/obsolete I wouldn't worry about manually providing the FCS.

-- 
Aaron Turner
http://synfin.net/
http://tcpreplay.synfin.net/ - Pcap editing and replay tools for Unix & Windows
Those who would give up essential Liberty, to purchase a little temporary
Safety, deserve neither Liberty nor Safety.
    -- Benjamin Franklin
"carpe diem quam minimum credula postero"
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