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Message-ID: <50cd4e5f0802071338h63b4fcbax9ceb9643aa5d7504@mail.gmail.com>
Date: Thu, 7 Feb 2008 15:38:05 -0600
From: "Biks N" <freebsd.dev@gmail.com>
To: "Sam Leffler" <sam@errno.com>
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	<47AB7775.2040000@errno.com>
Cc: freebsd-hackers@freebsd.org
Subject: Re: retrive data from mbuf chain
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On Feb 7, 2008 3:26 PM, Sam Leffler <sam@errno.com> wrote:
>
> Biks N wrote:
> > Hi,
> >
> > I am new to FreeBSD kernel programming.
> >
> > Currently I am trying to work on mbuf data manupulation.
> >
> > >From my understanding: data (payload) is stored into one or more mufs
> > which are chained together through m_next pointer.
> >
> > Now, I need to retrive all data in mbuf chain ( mbufs linked by
> > m_next). I am working ip_output() in netinet/ip_output.c
> >
> > Does there exist inbuilt function/macro to retrive all the data in mbuf chain?
> >
>
> man 9 mbuf; look for m_copydata.


m_copydata(mbuf, offset, len, buf)

Will it copy data from entire "mbuf chain" or just from the current mbuf ?

Thanks for your help


>
>    Sam
>
>