Wouldn't it be better to make sure a MacPorts installation always stays within /opt/local?

[MK-MacPorts at techno.ms]

I just wanted to set up a 2nd parallel MacPorts install - as I used to have it before moving to Mavericks…

Now I realise that it is probably not a good idea to have a setup like that after all.

Some applications install themselves into /Applications and have settings in /Library…

Assuming I have two MP installs setup as

	/opt/local
and
	/opt/local.trunk

I would have to be very careful when renaming those in such a way that I could use the installation in /opt/local.trunk!!!

I thought about simply renaming /opt/local to /opt/local.default and then have /opt/local.trunk renamed as /opt/local, but this is highly dangerous given the high likelihood which which installed files might reside outside /opt/local...

So, I guess, such a setup is rather to be avoided?!

I could redefine applications_dir as
---
 applications_dir        /opt/local/Applications/MacPorts
---
but the question is how can I trust every port that nothing else would be installed outside /opt/local?

I looks like though that it should be enough to have startupitem_install set to “no” in order to avoid messing with /Library/Launch(Daemons|Agents).