How does system upgrade handle files in /etc ?
I understand Ubuntu Linux is easily upgraded from one release to the next. My question is, how does an entire system upgrade handle the files in /etc ? For instance, in FreeBSD when I do a "make world" from version 6.0 to version 6.1, it does a diff on those files in /etc that have had things added to them in the new release and allows me to add those things in manually so that I don't mess up the changes I've made. What happens when you upgrade Ubuntu Linux from an old release to the latest and the new release has things that it has changed in /etc ?