Jonathan Yu <jaw...@cpan.org> writes: > To be fair, I don't think that inclusion in common-licenses is what you > think it is. Russ can correct me if I'm mistaken here, but my impression > is that common-licenses is around for a technical purpose: to conserve > on disk space where many packages share a common license (rather than > installing thousands of copies of a given file) as well as save some > disk space on mirrors (as individual packages using those common > licenses do not need to include the license text, and may simply refer > to the file in common licenses).
Jonathan's pretty much hit it on the nose here. The default, for any package in Debian, is to include the license with the package. This is clearly and obviously correct, it's the default expectation set by most of the licenses, and it requires no special thought or consideration. However, were Debian to do that, we would end up with over 10,000 copies of the GPL v2 in the archive because more than half of the software in Debian is covered by the GPL, at least in part. This just seems sort of silly. Hence common-licenses; it's there so that we don't install thousands of copies of the GPL on a typical system, basically. At least, that's how I look at it. common-licenses started, IIRC, with the licenses that are specifically called out in the DFSG as example free software licenses, which muddles matters somewhat, but all of those licenses are also extremely popular ones used by thousands of packages in Debian. (Except for the BSD license, which shouldn't have been there for a variety of reasons and which we're trying to get people to move away from referencing.) Here are the licenses that were part of common-licenses when I first started working on Policy, and the number of references: Artistic 2776 GPL (any) 21496 GPL (symlink) 8326 GPL 2 10821 LGPL (any) 7977 LGPL (symlink) 2134 LGPL 2 5689 LGPL 2.1 4084 As you can see, those are all into the "it would be rather silly to include a copy of this license in each of those packages" territory. Over time, we've added more licenses in those "groups": GPL 1 2159 GPL 3 3785 LGPL 3 947 The GPL v1 was added so that Perl could refer to its actual license rather than to the symlink that was then pointing to GPL v3, not because Debian thinks anyone should release new software (other than software licensed under the same terms as Perl for compatibility purposes) under the GPL v1. Notice that the LGPL is used quite a bit less than everything else on that list, but the assumption is that, over time, some of the 9600 other LGPL packages will probably move, so it will likely grow over time. Plus, it's strange to have one version of a license but not the others. We've also added some other licenses that seemed to reach the same threshold of "it's silly to ship this many separate copies of this license": Apache 2.0 1474 GFDL (any) 939 GFDL (symlink) 395 GFDL 1.2 550 GFDL 1.3 79 In retrospect, I think adding the GFDL was a mistake. Not only was it not used anywhere near as widely as it seemed like it would be when it was first released, but because we added it we got into a "trap" of adding newer versions, and the GFDL 1.3 by its usage count does not belong in common-licenses at all. But hindsight is always easier than foresight. The Apache 2.0 license is a fair bit below the other "core" licenses, but was added after the GFDL and is more widely used than it. The strongest candidate for inclusion that isn't currently in common-licenses is verison 1.1 of the MPL: MPL 1.1 740 Whether that's at the threshold where it's silly to include that many copies in the archive is something that's been debated back and forth without a clear consensus. -- Russ Allbery (r...@debian.org) <http://www.eyrie.org/~eagle/> -- To UNSUBSCRIBE, email to debian-policy-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/87hb0kfr8o....@windlord.stanford.edu
