[XeTeX] TeXLive update issues

[Gareth Hughes]

Maxim Cournoyer wrote:
> I believe a guide would help. It's always good to have a definitive,
> specific source of information (say, manpages) and a more contextual one
> (detailed examples on a blog, for example). I would use it for sure, as
> I'm in the process of setting up TeXlive 2009. But I don't know how
> practical it would be to keep both installation. You would have to
> differentiate the names from both install to make them in your path at
> the same time? Or a "switch" variable to trigger the newer or older
> install. This would be easier to do. The way I'm going to go right now
> is install full TeXlive 2009 packages from standard install. Then try to
> make them work by default, adjusting path variables and such. If it
> works well, I'll keep this default installation (and possibly remove old
> TeXlive 2007) and if it causes too many issues I'll settle on using
> TeXlive 2007 for now, maybe copying key new contents to its tree if I'm
> missing a feature I want. 
> 

OK. I thought I knew what I was doing as I've messed around with my
installation for a long time. I looked at the following pages for a
guide on how best to do the update to 2009:

http://support.river-valley.com/wiki/index.php?title=Notes_on_TeX_Live_setup
http://neoarch.wordpress.com/2008/08/16/tex-live-in-ubuntu-without-the-packages/

I wanted to get 2009 to live as the texmf-local tree of my current
installation, but that's probably what has caused the problems. I can
verify that I have two complete and working installations of TeXLive
(2007 from Ubuntu repositories and 2009 from ISO). However, I cannot
interact with them from the command line. There may have been issues
about which bits of the installation I performed as root (which steps
should be performed as root?). I would hope that a little jigging around
with configuration files would get everything working perfectly. Of
course, there's always the 'nuclear option' of removing the repository
packages and reinstalling from the ISO, but I shouldn't have to do that.
Can anyone suggest a way through this?

Gareth.