From owner-freebsd-hackers@FreeBSD.ORG  Mon Oct 24 07:31:20 2005
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Date: Mon, 24 Oct 2005 10:29:41 +0300
From: Giorgos Keramidas <keramida@ceid.upatras.gr>
To: kamal kc <kamal_ckk@yahoo.com>
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Cc: freebsd <freebsd-hackers@freebsd.org>, freebsd <freebsd-net@freebsd.org>
Subject: Re: in_cksum() for ip packets with multiple mbufs
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On 2005-10-23 22:27, kamal kc <kamal_ckk@yahoo.com> wrote:
> one thing i would like to ask?
>
> does it make any difference if i free the mbuf 'm' passed to
> if_output() and pass my own mbuf to if_output.
>
> is the original mbuf referenced by any other pointers or global
> variables ??

If you are hooking your own functions right before if_output, then it
shouldn't be a problem.

> >     - If you are not *REALLY* copying the data of the mbuf, then the
> >       name of copy_the_memorybuffer() is very confusing.
>
> i didn't showed in the above code snippet but actually i am copying
> the data contained in the mbufs in a character array.

AH!  That makes more sense then :)

> thanks to you that the problem was solved (i don't
> know if it is completely ok). i found that
>    - i had made mistake in computing checksum.
>       earlier checksum was computed over the whole dat

Nice.  Glad to know it's fixed now.