r228700 can't dhclient em0

[Jilles Tjoelker]

On Tue, Dec 20, 2011 at 11:23:54PM +0400, Gleb Smirnoff wrote:
> Considering r228571: we need to specify vhid as additional address
> attribute in atomic manner, via one ioctl(). Address can't be first
> configured, and then made redundant, that would lead it to being
> static for a short period, sending gratutious ARP announcement, etc.

> An assumption that we are not allowed to change ABI for our own tools
> strongly discourages bringing in new features :(

Consider changing to a more flexible ABI that does not need to be broken
for new features. Examples are nmount(2)'s name-value pairs and GEOM's
XML topology descriptions.

This is initially more work and has poorer performance, but it may well
be worth it.

Process information reserves space in structures for future extension;
this is less flexible but performs better (which matters somewhat).

Another consideration is compatibility for 32-bit applications on 64-bit
kernels; a good ABI design will minimize the amount of code needed to
support that.

-- 
Jilles Tjoelker