The question is why? Damnation, every time I upgraded (clean installs, SL to L, L to ML) I had to manually re-enter VPN and PPPoE settings. Since I re-instated my stuff from a Time Machine backup, I have all my apps and stuff, but not the install receipts. If I want to know whether the stuff in /usr/local/etc/ImageMagick were installed by MacTex (or they are dregs of even more ancient installations) there is now way to say because the Receipt for MacTex is gone:
pkgutil --file-info /usr/local/texlive/2012/bin/x86_64-darwin/tex
volume: /
path: /usr/local/texlive/2012/bin/x86_64-darwin/tex
Though that file is installed by MacTex, which comes in a DMG and leaves a Receipt (though I installed MacTex 2012 when I was on Lion). No receipt, no way of doing pkgutil --files whatever.receipt.MacTex.would.leave and figure out what was installed where.
So, how do I keep my receipt and VPN/PPPoE settings when I reinstate stuff from Time Machine? Do I actually have to do things by hand? And before you ask, the performance hit of not doing a clean install is such that I would never do a OS upgrade over the old OS.