[TriLUG] C & sockets programming question

[Brian Weaver]

You can get the remote address (getpeername(2)), but as to which
interface (lo, eth0, eth1) the packet was received on... not sure
there is any easy way.

-Brian

On 7/27/05, Tanner Lovelace <clubjuggler at gmail.com> wrote:
> Are you asking for the interface on the remote side?  If so,
> I believe that information is not sent.  If you're asking about the
> interface information on the local side, I'm not sure you can get
> that either. You could try getsockname or getsockopt, but I don't
> think that either do what you want.  You could probably get the
> local IP address and through that, somehow, call out to
> ifconfig or something to get the local interface, but it would
> be horribly non-portable.
> 
> Cheers,
> Tanner
> 
> On 7/27/05, Charles Fischer <fischer at 4pi.com> wrote:
> > I am patching a C program that opens a TCP/IP socket and listens.  When
> > "accept" returns a connecting socket, the program calls a read routine that
> > does some checking.  It would be nice if this read routine knew the
> > interface's name (ie, lo, eth0 or eth1).  Does anybody know how to get the
> > interface's name from the socket ID (file ID)?
> >
> > Thanks
> > Charles Fischer
> >
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> 
> --
> Tanner Lovelace
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