>>> in which case the interface "name" and "address" (which have the
>>> same lifetime issues as the number)
>> I don't think so, not if numbers are assigned sequentually at boot
>> and never repeated.  In practice today, a 32-bit serial number will
>> never be repeated; a 64-bit probably will never be repeated for the
>> foreseeable lifetime of NetBSD.
> While this might be true,
>         u_short if_index;               /* numeric abbreviation for this if */
> in practice today 16-bit serial numbers are repeated.

They are?  I have trouble thinking of any situation not contrived for
the purpose where 64K interface creates occur without an intervening
reboot.  Where did you find such?  It's probably worth preserving as a
stress-test case....

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