On 22 July 2013 12:50, Eric W. Biederman wrote: > The text of the GPLv2 does not grant permission to use code released > under the GPLv2 under any other terms, including the terms of the GPLv3. > > dosemu relied upon the convention of a top level copying file for it's > copyright licensing terms. > > The copyright licensing terms were the text of the GPLv2. > > The option of a later version was not given. The code base was > exclusively under GPLv2.
It's a bit more subtle than that. In the very early days of dosemu no copyright file was included (COPYING was missing until 0.63.1.something in 1996), but those were the 'wild west' days and people just assumed it was GPL. Then at some point parts of the source code (notably the serial code and VGA emulator, 1995) got the explicit "v2 or later" statement (NONE had the v2 only statement). Then James MacLean added the GPLv2 copying file in 1996. However, clause 9 of GPLv2 states that: "If the Program does not specify a version number of this License, you may choose any version ever published by the Free Software Foundation. " which, because other source code files do not mention a version, means that they can be licensed under any GPL version, 1, 2, 3, or later. (This is Alan Cox' opinion about the Linux kernel: https://lkml.org/lkml/2006/1/31/284 that if no explicit v2 is mentioned anywhere, simply adding the v2 COPYING file does not make it v2 only.) But when Hans restricted to v2 in 1998, then it was unambiguous, from then on all modifications are v2 only, unless otherwise indicated. Same for the Linux kernel, when Linus added his note in 2000. As for the linking: GPLv3: has this in clause 1 (GPLv2 is more vague): Corresponding Source includes (...) the source code for shared libraries and dynamically linked subprograms that the work is specifically designed to require, such as by intimate data communication or control flow between those subprograms and other parts of the work. Now there is some control flow between a closed-source DOS and DOSEMU. Of course the DOS is of course not specifically designed to require DOSEMU, but DOSEMU requires some DOS. Whether it is "intimate" is rather vague. I do not consider it intimate (it's all going over interfaces documented in RBIL), so using or distributing DOSEMU with any DOS, I see no problems with, much like distributing the Linux kernel with some closed-source programs (which happens on a very large scale -- think of Android phones). So in that sense it is useful to clarify our intent (this is not an exception like in the LGPL, purely clarifying intent like in the Linux kernel); Hans feared that future GPL versions would be too restrictive and did not want to be subject to a license that is not yet known (giving some control to the FSF). I personally have no problem with "or later" because of clause 9 in GPLv2 that restricts itself to be similar in spirit in later version. But to relicense to "v2 or later" Stas needs permission (IMHO) from all copyright holders of modification post the 1998 restriction by Hans, or rewrite all this code. (like I mentioned Hans told me "v2 or v3" was fine with him, Alberto's simx86 was initially released under "2 or later", so that leaves only you (Eric) and Clarence as major contributors to ask, with a bigger number of smaller contributors). Bart ------------------------------------------------------------------------------ See everything from the browser to the database with AppDynamics Get end-to-end visibility with application monitoring from AppDynamics Isolate bottlenecks and diagnose root cause in seconds. Start your free trial of AppDynamics Pro today! http://pubads.g.doubleclick.net/gampad/clk?id=48808831&iu=/4140/ostg.clktrk _______________________________________________ Dosemu-devel mailing list Dosemu-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/dosemu-devel
