From: <do...@ni...> - 2000-05-22 16:56:53
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The original message from Hannu Koivisto asks whether one is allowed to distribute non GPL applications built from Clisp plus other (L)GPL lisp code. The basic problem is that (L)GPL is really meant for c code, not lisp code. The Clisp copyright specifically weakens the requirements in an appropriate way. You can write a common lisp program and distribute it as a Clisp image if you also offer the customer all he needs in order to build that image, i.e., the appropriate version of Clisp, the files that have to be loaded into it, and the directions for doing that. I see two probems when you want to distribute an application that contains some other (L)GPL code. 1. The Clisp copyright says: You may copy and distribute memory image files generated by the function SAVEINITMEM, if it was generated only from CLISP and independent work ... How about images generated from CLISP, other LGPL code, and independent work? Of course, if the other LGPL code is independent work, then the original copyright allows it. What we need is permission if it's not. 2. It's not so clear whether your code is "derived from" that other LGPL code. I notice that there's a file in the new Allegro web server that specifically addresses this problem. (Allegroserve is available from ftp://ftp.franz.com/pub/aserve/). I include the file license-allegroserve.txt below. I'd like to thank Franz both for attempting to clarify this subject and for releasing code under that license. I think it would be useful to add that sort of clarification to the code in libraries (such as CLOCC). I guess I'm proposing a new license, the "LispGPL", which is suitable for lisp code. ================ Prequel to the Gnu Lesser General Public License Copyright (c) 2000 Franz Inc., Berkeley, CA 94704 Franz Inc. has adopted the concept of the GNU Lesser General Public License version 2.1 ("LGPL") to govern the use and distribution of AllegroServe. However, LGPL uses terminology that is more appropriate for a program written in C than one written in Lisp. Nevertheless, LGPL can still be applied to a Lisp program if certain clarifications are made. This document details those clarifications. Accordingly, the license for AllegroServe consists of this document plus LGPL. Wherever there is a conflict between this document and LGPL, this document takes precedence over LGPL. A "Library" in Lisp is a collection of Lisp functions, data and foreign modules. The form of the Library can be Lisp source code (for processing by an interpreter) or object code (usually the result of compilation of source code or built with some other mechanisms). Foreign modules are object code in a form that can be linked into a Lisp executable. When we speak of functions we do so in the most general way to include, in addition, methods and unnamed functions. Lisp "data" is also a general term that includes the data structures resulting from defining Lisp classes. A Lisp application may include the same set of Lisp objects as does a Library, but this does not mean that the application is necessarily a "work based on the Library" it contains. The AllegroServe Library consists of everything in the AllegroServe distribution file set before any modifications are made to the files. If any of the functions or classes in the AllegroServe Library are redefined in other files, then those redefinitions ARE considered a work based on the AllegroServe Library. If additional methods are added to generic functions in the AllegroServe Library, those additional methods are NOT considered a work based on the AllegroServe Library. If AllegroServe classes are subclassed, these subclasses are NOT considered a work based on the AllegroServe Library. If the AllegroServe Library is modified to explicitly call other functions that are neither part of Lisp itself nor an available add-on module to Lisp, then the functions called by the modified AllegroServe Library ARE considered a work based on the AllegroServe Library. The goal is to ensure that the AllegroServe Library will compile and run without getting undefined function errors. It is permitted to add proprietary source code to the AllegroServe Library, but it must be done in a way such that the AllegroServe Library will still run without that proprietary code present. Section 5 of the LGPL distinguishes between the case of a library being dynamically linked at runtime and one being statically linked at build time. Section 5 of the LGPL states that the former results in an executable that is a "work that uses the Library." Section 5 of the LGPL states that the latter results in one that is a "derivative of the Library", which is therefore covered by LGPL. Since Lisp only offers one choice, which is to link the Library into an executable at build time, we declare that, for the purpose applying LGPL to the AllegroServe Library, an executable that results from linking a "work that uses the AllegroServe Library" with the Library is considered a "work that uses the Library" and is therefore NOT covered by LGPL. Because of this declaration, section 6 of LGPL is not applicable to the AllegroServe Library. However, in connection with each distribution of this executable, you must also deliver, in accordance with the terms and conditions of the LGPL, the source code of AllegroServe Library (or your derivative thereof) that is incorporated into this executable. |