On Sat, Nov 1, 2008 at 2:35 AM, alunw <[EMAIL PROTECTED]> wrote: > > Thanks for this. > > I'll certainly consider doing this, though I'm still slightly > concerned about the implications for my own code. I guess using the > GPL is probably as good a way as any of deterring potential commercial > competitors from "stealing" my code - though I'm not really expecting > or even wanting to get rich it anyway. > > I'll post a suitable version on my web site in a day or two, and > donate that. I hope it proves useful.
To summarize, I guess a common theme that has been raised in this thread is that of licensing one's own work (no-brainer, right? :-). I personally favour the GPL, but that doesn't necessarily mean that I hate anything that's not GPL'd. I'm a big fan of the XFCE desktop environment, many components of which are covered by the BSDL. As Ronan, Timothy and William (did I miss anyone?) mentioned in this thread, there's also the dual license model. But in this case, the issue gets a bit trickier. Here, I'll restrict my discussion to the following projects: Berkeley DB, MySQL, Qt and Sendmail. All four of these are open source projects covered by a dual license. For each such project, there's an open source version as well as a closed source, proprietary version. Here's a brief summary: * open and proprietary code different: Sendmail * open and proprietary code same: Berkeley DB, MySQL, Qt Sendmail as an open source project is developed by a community consisting of volunteers and other interested parties. However, the closed source version is developed by Sendmail, Inc. and the company does receive royalties from licensing its closed source version. Qt was originally licensed under terms which many people considered not open source or not GPL compatible. I think a consequence of this was that the GNOME project took off in order to develop an alternative to the KDE desktop environment, which originally was developed with Qt using the above licensing terms. Fortunately (to me, at least), Trolltech revised the licensing terms and now Qt is GPL compatible. You can say that there's only one version of Qt, that's the open source version. If you use Qt in an open source project (that's GPL compatible), then you don't have to pay any cash to the company that owns the copyright to Qt. However, the same open source version of Qt can also be covered by a business license. This means that if you use Qt in a closed source, propriety product and you plan to distribute that product for royalties, then legally you must obtain a "business" license from the company that owns the copyright to Qt (translation: pay the dough to get the go). Berkeley DB (BDB) is dual licensed, but versions earlier than 2.0 were covered by the BSD license. I think Oracle now owns the copyright to Berkeley DB; please correct me if I'm wrong. The code base of BDB is released as open source and you're at liberty to use it in open source projects. As is the case with Qt, you must obtain a "proprietary" license from Oracle in order to use BDB in your closed source, proprietary product and make money from that product via licensing. Note that code contributions to BDB can come from any interested parties, so if you want, you can contribute a patch to the BDB code base. But I think the point to note is that your patch would likely not be merged into that code base. Most if not all of BDB is developed internally, even though the code base is released as open source. So if your patch is good enough and the BDB folks really want to use it, then it's very likely that they would re-implement your patch and merge that re-implementation with the BDB code base. This is a safeguard against future litigations concerning copyrights, who owns what, who does what and when, etc. We can find a similar issue with MySQL. The MySQL code base has recently been forked, I think, in order to create a new database project called drizzle. The drizzle project is currently under development as an open source project by MySQL employees (or Sun employees, if you like, since MySQL AB has been bought by Sun for a truck load of money). At the moment, I see little to no competition between MySQL as a project and drizzle, since the latter aims to be a database work horse if you like for this new trend called "cloud computing". Its design is sort of like a microkernel design (think GNU hurd), and it aims to likely support 64 bit computing only. So what I'm saying is that releasing your code under the GPL doesn't mean you can't make money from what you've done. There are precedents such as those mentioned in this thread, and open source business models. But from my perspective, I personally favour the GPL because it allows students (yours truly :-) to study, modify, experiment with your code. You might not appreciate this, but doing so can be beneficial to generations of students, not just university students and high school students, but everyone who is able to access your code and learn from it. I'm very delighted that you've considered making your code GPL compatible, more so because I'm also interested in automata theory (a novice actually). -- Regards Minh Van Nguyen Web: http://nguyenminh2.googlepages.com Blog: http://mvngu.wordpress.com --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-devel@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
