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To: Aniruddha Bohra <bohra@cs.rutgers.edu>
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Cc: freebsd-questions@freebsd.org
Subject: Re: Writing raw PPP packets
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Aniruddha Bohra <bohra@cs.rutgers.edu> writes:

>     From the bpf(4) manpage :
> 
> A packet can be sent out on the network by writing to a bpf file descrip-
>      tor.  The writes are unbuffered, meaning only one packet can be
> processed
>      per write.  Currently, only writes to Ethernets and SLIP links are sup-
>      ported.
> 
> 
>     Is it possible to direct IP packets to the PPP interface without
> the kernel
> routing the packets? This is for a case where the default address to a
> host is over another interface and I want to force some packets
> through the PPP
> interface.

Sure, you can do it that way.
But (if I remember correctly; it's not my usual IP implementation)
normal socket operations should let you bind to an interface anyway.
Via its address, maybe.