> It definitely shouldn't be managed by sysctl - it's much more like a
> network ioctl than it is like other sysctl things.  But hanging an IP
> source address of of every routing entry is going to be bloaty, 

There wouldn't be much in the way of data bloat -- the address is
already there, in the form of a pointer to an ifaddr.

> and it could be unreliable if there is more than one applicable
> route - what if you send TCP packets from one source sometimes, and
> a second source other times?

Maybe I'm misunderstanding the issue, but the source address gets
copied into the pcb when the connection gets established, so your src
addr won't change mid-connection..

> It may be the right thing to do, but it bears careful consideration.

Agreed.  definitely something worth careful design and prototyping..

					- Bill