questions about 4.3BSD struct ifnet.if_addrlist

[Michael A. Ziober]

(Since I received no response to my previous posting and I have been
unable to find the information anywhere else, I am going to ask again
in the hopes that this time I will strike gold. :-)

We are trying to implement a network interface on an Omron SX-9100
workstation running 4.3BSD.  When implementing the pseudo-device, we
had some questions about the network interface data structures
(described on page 316 of the book "The Design and Implementation of
the 4.3BSD UNIX Operating System").  The questions are related to the
struct ifnet.if_addrlist:

    - Does my procedure rpattach() (When attaching the pseudo-device
      to the system) initialize this address list?
    - If so, what should it be?  Should it be initialized to NULL?
    - If not, who should do the initialization?

    - When using this field in the structure (for example to send a
      packet) how do I find the appropriate address to use from this
      list?

    - In the routine rpioctl() (for the SIOCSIFADDR and SIOCSDSTADDR
      commands), does it add new address to the address list?
    - Does it replace any existing entries by matching address families?

In short: How is this address list handled?  Who initializes it?  Who
modifies it?  How is it done?  How it it maintained?

Sorry about the noise, but this project needs some help to get it over
this hurdle.

Thanks for ANY help,
Michael Ziober