Why does Macports reinstall already available software?

[Ryan Schmidt]

On Oct 9, 2012, at 08:24, Jakob van Bethlehem <jsvanbethlehem at gmail.com> wrote:

> As a brand new user of macports I may oversee some obvious places to look for answers, if so, my apologies - I'm always happy with a reference to the appropriate documentation documents. But sofar I have been unable to figure out an answer to the following scenario:
> - I have a system that has already some package installed, e.g. subversion 1.7.6 (same happened for Python 2.x series) in /usr/local/
> - Next I try to install a macport of some package that has these software suites as a dependency (in this case eric4, or bluefish for the Python-case)
> - Macports installs a brand new version of those dependencies in /opt/local.... why?
> 
> Short of the unneeded use of hd-space, this gives me enormous headaches in setting my PATH correctly, and afaics for no reason. So, what's what I can't see (yet) ?

https://trac.macports.org/wiki/FAQ#syslibs

Also, we recommend you do not have software installed in /usr/local if you want to use MacPorts:

https://trac.macports.org/wiki/FAQ#usrlocal