Interface name aliases (was: Specifying names for tap interfaces)

[Edgar Fuß <ef%math.uni-bonn.de@localhost>]

> I think we could have both a device name and a device name alias for an
> interface (lets call them xname and xalias for now). The xname would still
> be as it is righ now (i.e. bge0 or tap3, bridge1, ...)
I like that idea, but one may have to think very carefully about
some details.

Suppose you have bge0 aliased as en0 and wm0 as en1.

Should the output of ifconfig bge0 (or -a) show something like
        name-alias: en0
?

What should ifconfig en0 do? Give an error or behave like ifconfig bge0?

What should ifconfig -l output? bge0 and wm0 or en0 and en1 or both?

How should "block all on bge0; pass all on en0" behave?

This is the usual problem of "take x" and "enumerate and pick x" potentially
behaving differently (like "ls CamelCase" and "ls | grep CamelCase" on a
case-preserving file system).