Re: notion of a local address [was: Re: ioctl SIOCGIFNETMASK: ip alias

[Wietse Venema]

Steve VanDevender:
> Wietse Venema writes:
>  > If an MTA receives a mail relaying request for [e-mail]
>  > then it would be very useful if Linux could provide the MTA with
>  > the necessary information to distinguish between local subnetworks
>  > and the rest of the world. Requiring the local sysadmin to enumerate
>  > all local subnetwork blocks by hand is not practical.
> 
> I think you're making a couple of unjustified assumptions here:

You are making unjustified assumptions:

If the kernel knows about subnets, then an application should be
able to find out about them. Whether or not you agree with the
application's reasons does not matter.

To close with yet another analogy:

A musician complained to Mozart that his music was so difficult to
play. Mozart asked: are these notes on your instrument? The musician
replied: yes. Mozart said: so play these notes.

	Wietse