Dear David Roundy and darcs-devel: One year ago I suggested that the copyright holders of darcs should add a special exception to the license which would allow darcs to be combined with Eclipse, SWT, and related code and redistributed, without allowing darcs to be combined with proprietary code and redistributed.
http://www.abridgegame.org/pipermail/darcs-users/2005-June/007658.html The discussion was heated and controversial, but in the end David Roundy wholly supported the idea, but needed someone else to do the labor of contacting each of the copyright holders and requesting permission from them. An important point to bear in mind is that this exception to the darcs licence would not make it so that people are allowed to combine proprietary source code with darcs source code and redistribute the result. The GPL forbids people from combining GPL'ed source code with proprietary source code and redistributing the resulting combined work, and this exception would do nothing to weaken that constraint. The only thing that this exception would do would be to allow darcs source code to be combined and redistributed with other other Free Software. Now I am thinking about the unfortunate fact that darcs 1.0.7 cannot offer the valuable new single-ssh-connection feature on Windows because putty -- the Windows ssh client that darcs uses -- doesn't support the SSH ControlMaster feature. As the maintainer of the darcs package for Windows, which includes putty, I would like to replace putty with OpenSSH (this will also require changing darcs to invoke ssh in a more general way, or perhaps in a parameterized way). However, OpenSSH depends upon OpenSSL and the license if OpenSSL is incompatible with the GPL. Combining darcs with OpenSSH in this way is arguably already allowed by the respective licenses of darcs and OpenSSH, but: a) It depends upon interpreting this packaging of darcs as being "mere aggregation" instead of being "a combined work", which is, well, open to interpretation. b) This might change for the better or for the worse if people start redistributing darcs under version 3 of the GPL. I'm not sure what change, if any, version 3 of the GPL would bring to this issue. c) It precludes some hypothetical future hacks, for example accessing ssh functionality by direct FFI instead of by executing a separate process. d) While this work-around might suffice for combining darcs with openssh, it might not suffice for combining darcs with Eclipse or SWT. Therefore, I would like to ask permission from you, the authors of darcs, to combine darcs with openssh, Eclipse, and SWT. I hereby ask the copyright holders to grant me permission to use the code to which they hold copyright with the following amendment to the GPL: "As a special exception, you have permission to link this program with code which is licensed under the Common Public Licence, the Eclipse Public Licence, or the OpenSSL License, as long as you follow the requirements of the GNU GPL in regard to all of the software in the executable aside from the software which is licensed under the Common Public License or the Eclipse Public License." This amendment is modelled on the amendment that the FSF used to suggest to work-around the old Qt license incompatibility: http://www.fsf.org/licensing/licenses/ Just to reiterate, this special exemption would *not* allow darcs nor any part of darcs to be used in a proprietary, non-Free work. The only thing that it would allow that is not currently allowed is for darcs to be used in combination with other Free Software such as Eclipse and OpenSSH. Regards, Zooko _______________________________________________ darcs-devel mailing list darcs-devel@darcs.net http://www.abridgegame.org/cgi-bin/mailman/listinfo/darcs-devel
