On 10 Nov., 13:33, Maarten Derickx <m.derickx.stud...@gmail.com> wrote: > I like your ideas about guest distributions Georg. >
Thanks! > The missing thing you describe: "a way to tell the host distrubution on > what packages we depend" is not really the missing thing. I think a way to > make sage configurable to use other external program's instead of spkgs is > really the missing thing. The Sage build system already is somewhat overstretched. Since Sage has the motto of "building the car instead of reinventing the wheel", we would have long ago switched to some other build system, if there would be one available, providing all the features that make Sage "great" (see the other posts in this thread). IMHO, the Bitbucket (?) project of Burcin Erocal (I don't have a link at hand at the moment) is a step in the right direction. The Gentoo Prefix buildsystem would need to evolve a bit in the "Sage direction" to be a real alternative, here the work of Francois and Christopher and the others is invaluable. As for using the host distribution C compiler, I think Volker Braun has very good and well-thought-out proposals about using compiler-wrapper mechansims. So progress may be slow, but steady! > Since it is not our responsibility to make > packages specific to a distribution. And the configuration file I mentioned > would allow the person packaging sage for say debain to just put some stuff > in that file so sage knows where to find the packages (it would be a non > trivial effort to make such a configuration file also work tough). And > leave the generation of the deb file to the guy packaging sage for debian. I was thinking of a dynamic functionality, i.e. in the sage guest distribution, one could more or less freely switch on and off whether a certain library (say) comes from the sage guest distribution itself, or else from the host distribution. E.g. simply for development and/or testing purposes, maybe even making a specific choice of the version. And then the host distribution should receive a virtual package that (newly so) requires as a dependency exactly this version of that library. A person packaging sage for debian could not possibly know, what in the future, users might choose to dynamically set. > > Responding to you P.S.: > > Well, according to the CPL licence you are allowed to link against the CPL > licenced libraries without using the same licence as them (or even without > opensourcing) so this incompatibility is not that bad right? The CPL is considered a free software license and is not a problem as such, it's rather the fact that it is considered being incompatible with the GPL (see http://www.gnu.org/licenses/license-list.html#CommonPublicLicense10) and the consequences of the copyleft part of the GPL, see especially http://www.gnu.org/licenses/gpl-faq.html#GPLIncompatibleLibs . Technically, one can for example compile bash under UWIN. The bash source is GPL, but it (resp. the binary) would have to rely on the readline library (OK), msvcrt.dll (the Microsoft system C library/ runtime, which is also OK, since this case is covered by the "system library" exception clause, see above link, or e.g. GPL v3 section 1), but also the UWIN posix.dll and ast.dll support libraries. For the latter, the "system library" exception does not apply (IANAL, but that seems undisputable to me, reading the license texts). And since nowhere in the bash source license files, the UWIN posix.dll and ast.dll are mentioned as "additionally allowable" libraries to link against --- it is not granted to do so. There are differing opinions about that, see e.g. footnote [5] on the table at http://www.osscc.net/en/licenses.html#compatibility . But on the one hand, a final decision on that matter probably can only be obtained by a court ruling (that's not where I go!). On the other hand, I personally am inclined simply to respect the GNU folks' point of view (even if it might not be ultimately enforcable by the choice of license/law text they are currently using). Why should I not? Cheers, Georg -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
