Hi Yaroslav, Le Fri, Dec 12, 2014 at 12:07:41PM -0500, Yaroslav Halchenko a écrit : > > If we have a library X in Python, released under some GPL-compatible > license (e.g. BSD-3 or Expat) and then using (optionally) some GPL code > (at run time) provided by another library Y -- what are the implications? > Am I wrong on any of the following statements > > - the project X codebase doesn't have to be relicensed to GPL
Right > - the project X can use project Y (since under GPL compatible license) Right. Much of the GPL is about redistribution, not use. > - It is only at 'run time' when actual linking to the library Y happens, > so project must comply with GPL but whose responsibility it is then > and what needs to be enforced? > > - original distributor of X must have provided all the sources with > modifications? But it was user's decision to use GPL'ed library If the distributor of X distributes only X and asks the users to do all the extra work, then it does not have to redistribute the sources of Y. > - or user must somehow make sure he has the sources... (sounds > dubious) Indeed. > - is mere ability to be used with GPL licensed library Y makes > distributors of code of X required to comply with GPL? (e.g. provide > modified sources) No, but the distributors of X would start to have obligations if they would distribute X and Y together, for instance as a binary form. In the case of Debian, since our archive contains the source packages, package-X can depend on package-Y or contain code derived from package-Y without needing extra work on the redistribution. (Of course, the maintainer of package-X has to ensure that liceses are compatible). > [1] http://mail.scipy.org/pipermail/nipy-devel/2014-December/010707.html If a third party download X and Y from their original distributors, and redistribute the combination as binary code without the source, then they will violate the GPL. Thus, even if X is their main interst, if they download Y because X needs it, they need to read Y's license. If X provides some download scripts for Y, it would be kind to write somewhere in the documentation that Y is GPL-licensed. Have a nice week-end, -- Charles Plessy Tsurumi, Kanagawa, Japan -- To UNSUBSCRIBE, email to debian-legal-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: https://lists.debian.org/20141213001602.gc26...@falafel.plessy.net