Thread: Theory and practice of free software
I was asked this off-list but thought a cc: to the list was appropriate: > If, as you say, Postgres can't use a GPL'd library, does that mean that > Postgres itself isn't GPL'd? If so, then what is it? I'm having trouble > understanding all of the nuances of open source, GPL, etc. Postgres is distributed under the BSD license, which is a little bit different from GPL in the detailed terms of what recipients can and can't do with the software. In particular BSD does not place a requirement on a recipient to further redistribute the code. There are several other popular variants on the theme of free source code. There is a brief overview of common open-source licenses at http://www.cs.mu.oz.au/~trd/www-free/license_categories.html. I have seen a more thorough treatment recently, probably at one of the big open-source sites like Debian or Cygnus, but I can't find it right now :-( ... anyone have a better link? Some other good pages that came up while looking: http://www.fsf.org/philosophy/categories.html (server badly overloaded) http://www.debian.org/intro/license_disc.html http://metalab.unc.edu/pub/Linux/LICENSES/theory.html http://www.opensource.org/osd.html http://www.debian.org/social_contract http://www.fsf.org/philosophy/free-sw.html For background and historical material about hacking culture, it's difficult to do better than Eric Raymond's writings. See for example http://www.tuxedo.org/~esr/writings/homesteading/ regards, tom lane