if_addrlist in AF_INET domain

Ed Gould ed at mtxinu.UUCP
Sat Apr 19 12:01:17 AEST 1986


>I'm a little confused by the addition of lists of addresses for each network
>interface in the 4.3BSD (beta) release.  Scanning the code leads me to believe
>either that the implied functions (multihoming per i/f) aren't fully
>implemented, or that I'm just misinterpreting this feature.
>
>Could someone describe in a nutshell what additional capabilities
>this change gives us, and how they might be exploited?

I think you're misinterpreting it.  The address list is designed
to allow different address families to share the same interface,
e.g., INET and NS.  The chained structure (struct ifaddr) has
a struct sockaddr as its first component.  This structure contains
an address family designation.  To find the correct address for an
interface, one looks down the chain of ifaddr's until a correct
address family is found in a sockaddr.  That sockaddr contains
the address.

-- 
Ed Gould                    mt Xinu, 2910 Seventh St., Berkeley, CA  94710  USA
{ucbvax,decvax}!mtxinu!ed   +1 415 644 0146

"A man of quality is not threatened by a woman of equality."



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