/usr/local question

[Jan Stary]

On Apr 04 16:05:27, Jeremy Lavergne wrote:
> > "/usr/local is not a viable choice because some software
> > (especially auto* tools from Gnu) look in /usr/local
> > as a default location, which means MacPorts can't be
> > easily isolated when needed."
> > 
> > I want to kindly ask the person who wrote this to elaborate,
> > and be as specific as can be: what exactly does it mean for macports
> > to be "isolated", and how exactly does e.g. auto* looking into
> > /usr/local stand in the way of it?
> 
> As with the software that magically found its way into /usr/local, how do we stop that very same software from clobbering what MacPorts has installed there?

You keep saying that: "the software that magically finds its way to
/usr/local". What do you even mean by that? The user installed it
there; that's about the only way something gets into /usr/local.

And how do we stop the user from rewriting something that is already there?
We don't, and we can't. It's the user's responsibility to not be an idiot
and rewrite something he has installed himself before.

In fact, what difference does "/usr/local or /opt/local"
(or any ther prefix for that matter) make in this respect?
In the current state of things, how do you stop the user
from overwriting something that macports has installed under
/opt/local?

You don't, because you can't. It's the user's responsibility
to not install over something that is already installed
(whatever the prefix is).