Multiple instances of pkgsrc: more documentation needed (probably)

[Ottavio Caruso <ottavio2006-degen%yahoo.com@localhost>]

Question from somebody who has used pkgsrc on and off on netbsd and
still struggles to use it properly on Linux (I've tried Centos 7 and
LMDE so far).

This is the only piece of information from the official guide:
https://www.netbsd.org/docs/pkgsrc/platforms.html

"Note: It is possible to bootstrap multiple instances of pkgsrc using
non-intersecting directories. Use bmake corresponding to the
installation you're working with to build and install packages."

While simple in principle, this is more complicated in practice.

Assume for example a non-NetBSD host machine. Let's say I want to have
three pkgsrc roots (vanilla latest stable, vanilla current, and a
forked one from third parties). To make things easier, all the three
of them are bootstrapped with --unprivileged on non intersecting paths
on the filesystem.

It's all ok if I "bmake" and "bmake install" using absolute paths. The
resulting binaries will be installed in different directories.

But what if I want to run the installed packages in cascading order?

Let's say I modify $PATH to run:

/path-to-stable/pkg/bin:          # first
/path-to-current/pkg/bin:          # second
/path-to-3rdparty/pkg/bin:       #third
$PATH                                  #native OS binaries last.

Would/wouldn't any conflct arise at any point?

Has anybody practical experience of such a configuration?

-- 
73 de ottavio M6OTV