name". If it doesn't have a description, on OS X, use the System
Configuration framework to attempt to get a "friendly name" for
interfaces.
If a loopback device doesn't have a friendly name, give it "Loopback" as
the friendly name.
Move the "turn a CFString into a mallocated C string" routine into
common code, as it's used in more than one place.
svn path=/trunk/; revision=46131