MCCABE@MTUS5.BITNET (Jim McCabe) (02/18/90)
I've recently become familiar with lex and yacc, and am wondering about
the legal status of the code generated by these programs. Is it legal to
use a yacc-generated compiler (and a lex-generated lexical analyzer)
for part of a public-domain software package? For example, if I used lex
and yacc in a language interpreter I wrote, would it be permissable to
distribute my program freely over networks and such? In the Sun lex and
yacc manuals, they never mention this at all, so I'm worried. ;)
Jim McCabe
MCCABE @ MTUS5.BITNETmeissner@osf.org (Michael Meissner) (02/21/90)
In article <90049.104719MCCABE@MTUS5.BITNET> MCCABE@MTUS5.BITNET (Jim McCabe) writes: | I've recently become familiar with lex and yacc, and am wondering about | the legal status of the code generated by these programs. Is it legal to | use a yacc-generated compiler (and a lex-generated lexical analyzer) | for part of a public-domain software package? For example, if I used lex | and yacc in a language interpreter I wrote, would it be permissable to | distribute my program freely over networks and such? In the Sun lex and | yacc manuals, they never mention this at all, so I'm worried. ;) I don't know about Berkeley Unix, but System V.2 changed the license agreement such that the output of lex and yacc does not require a UNIX license, and may be distributed freely. To actually run lex and yacc, still requires a UNIX licence. I believe, but have no direct knowledge that Berkeley Yacc's output can be used without an AT&T derived licence. Bison from the Free Software Foundation (bison is a yacc replacement) does require that anything using bison, be subject to the same terms that bison is (the copyleft) -- basically where the full source must be available (not necessarily free), and that you can't place redistribution rights on third parties who get either your source or binaries. I don't know what the terms for FLEX (the faster lex) are. -- Michael Meissner email: meissner@osf.org phone: 617-621-8861 Open Software Foundation, 11 Cambridge Center, Cambridge, MA Catproof is an oxymoron, Childproof is nearly so
kan@dg-rtp.dg.com (Victor Kan) (02/21/90)
In article <90049.104719MCCABE@MTUS5.BITNET> MCCABE@MTUS5.BITNET (Jim McCabe) writes: >I've recently become familiar with lex and yacc, and am wondering about >the legal status of the code generated by these programs. Is it legal to >use a yacc-generated compiler (and a lex-generated lexical analyzer) >for part of a public-domain software package? For example, if I used lex >and yacc in a language interpreter I wrote, would it be permissable to >distribute my program freely over networks and such? In the Sun lex and >yacc manuals, they never mention this at all, so I'm worried. ;) It all depends on how you distribute your program. If you release the source code as PD before you pass it through Lex and Yacc, there's probably nothing anyone can do to stop you. People who want to use your software can just use their licensed copies of Lex and Yacc. Or they may use Bison or Bob Corbett's Berkeley Yacc. There may be a PD Lex out there, or someone my convert your Lex code to Flex. But if you intend to distribute only C code, i.e. after you've run your work through the "Official" Lex and Yacc, you can be prosecuted for copyright infringement! That's because Lex and Yacc include copyrighted data files into their analyzers and parsers (/usr/lib/lex/n[cr]form and /usr/lib/yaccpar, respectively). If you pass the Yacc grammar through Bison for distribution, your parser, and perhaps your entire program will fall under the Free Software Foundation's COPYLEFT. For true PD status, you'd have to use Bob Corbett's Berkeley Yacc which has been made PD by the author, I believe. The same thing goes for your Lex code. > Jim McCabe > MCCABE @ MTUS5.BITNET | Victor Kan | I speak only for myself. | *** | Data General Corporation | Edito cum Emacs, ergo sum. | **** | 62 T.W. Alexander Drive | Columbia Lions Win, 9 October 1988 for | **** %%%% | RTP, NC 27709 | a record of 1-44. Way to go, Lions! | *** %%%
jwl@ernie.Berkeley.EDU (James Wilbur Lewis) (02/21/90)
In article <271@xyzzy.UUCP> kan@tom.dg.com () writes: -In article <90049.104719MCCABE@MTUS5.BITNET> MCCABE@MTUS5.BITNET (Jim McCabe) writes: ->Is it legal to ->use a yacc-generated compiler (and a lex-generated lexical analyzer) ->for part of a public-domain software package? - -But if you intend to distribute only C code, i.e. after you've run -your work through the "Official" Lex and Yacc, you can be prosecuted -for copyright infringement! That's because Lex and Yacc include -copyrighted data files into their analyzers and parsers -(/usr/lib/lex/n[cr]form and /usr/lib/yaccpar, respectively). I just looked; none of these files contain copyright notices. It'd be silly to copyright those files, because that would render these tools useless for commercial software development! You couldn't even distribute the binaries because they're derivative works (right?) (The Bison skeleton is another story -- the reason it's copyrighted is not to *prevent* copying, but to *encourage* people to share their (and FSF's!) code.) -- Jim Lewis U.C. Berkeley
johnl@esegue.segue.boston.ma.us (John R. Levine) (02/22/90)
In article <271@xyzzy.UUCP> kan@tom.dg.com () writes: >But if you intend to distribute only C code, i.e. after you've run >your work through the "Official" Lex and Yacc, you can be prosecuted >for copyright infringement! ... I wish people would check their "facts." AT&T has for several years explicitly permitted programs built with lex and yacc to be redistributed without restriction. The same goes for executables built with the C library. For those who don't like yacc and lex, Bob Corbett's Berkeley Yacc is entirely public domain. Vern Paxton's flex is subject to the Berkeley copyright (which allows unlimited redistribution so long as you include Berkeley's copyright and disclaimer.) The flex parser skeleton is public domain. -- John R. Levine, Segue Software, POB 349, Cambridge MA 02238, +1 617 864 9650 johnl@esegue.segue.boston.ma.us, {ima|lotus|spdcc}!esegue!johnl "Now, we are all jelly doughnuts."
kan@dg-rtp.dg.com (Victor Kan) (02/22/90)
In article <34421@ucbvax.BERKELEY.EDU> jwl@ernie.Berkeley.EDU.UUCP (James Wilbur Lewis) writes: >In article <271@xyzzy.UUCP> kan@tom.dg.com () writes: >-In article <90049.104719MCCABE@MTUS5.BITNET> MCCABE@MTUS5.BITNET (Jim McCabe) writes: >->Is it legal to >->use a yacc-generated compiler (and a lex-generated lexical analyzer) >->for part of a public-domain software package? >- >-But if you intend to distribute only C code, i.e. after you've run >-your work through the "Official" Lex and Yacc, you can be prosecuted >-for copyright infringement! That's because Lex and Yacc include >-copyrighted data files into their analyzers and parsers >-(/usr/lib/lex/n[cr]form and /usr/lib/yaccpar, respectively). > >I just looked; none of these files contain copyright notices. Hmmm. I just looked at another machine (i386 running 386/ix) and its version of those files have no copyright notices in them. When I first posted, I only looked on my workstation (m88k running DG/UX). It's files do have copyright notices in them. Since someone has responded to this query saying that AT&T has changed the license for Lex and Yacc output, I assume that it would be OK to distribute the output. (I can't be sure, so don't rely on what I say :-) >It'd be silly to copyright those files, because that would >render these tools useless for commercial software development! >You couldn't even distribute the binaries because they're derivative >works (right?) No, it wouldn't render Lex and Yacc useless for commerical software development. Users with commercial Unix licenses are allowed to distribute their products via their licensing agreement. That's what licenses are for. Users of those binaries will most likely be running them on machines with a Unix licenses as well (unless they're running Mach in BSD-emulation mode). I remember when it came time for Columbia Univ. to renew some of it's SunOS licenses last year. I assume that if a machine's Unix license expires, it becomes illegal for that machine to run anything compiled with any tools, libraries, header files, etc., which do fall under the license agreement. Presumably, people who generate software for machines using shared or dynalink libraries are somewhat luckier than those generating pure executables because they don't have to include copyrighted libraries in their binaries. This one I am sure of: header files in /usr/include on SysV contain AT&T proprietary source code copyright notices that prohibit distribution of those header files. A company can distribute software compiled with those header files because their license with AT&T allows them to do so. >(The Bison skeleton is another story -- the reason it's copyrighted is not >to *prevent* copying, but to *encourage* people to share their (and FSF's!) >code.) True, but it prohibits you from releasing the generated C code into the public domain, as the original poster implied. COPYLEFT != PD !!!!! But let's not start the Nth Copyleft debate. BTW, I love GNU stuff and use it all the time. I'm not sure I like/dislike the Copyleft, but I know I like the software. Isn't there a copyright notice for the Trustees of UC in the /usr/include header files on BSD Unix? >-- Jim Lewis > U.C. Berkeley | Victor Kan | I speak only for myself. | *** | Data General Corporation | Edito cum Emacs, ergo sum. | **** | 62 T.W. Alexander Drive | Columbia Lions Win, 9 October 1988 for | **** %%%% | RTP, NC 27709 | a record of 1-44. Way to go, Lions! | *** %%%
henry@utzoo.uucp (Henry Spencer) (02/23/90)
In article <292@xyzzy.UUCP> kan@tom.dg.com () writes: >>I just looked; none of these files contain copyright notices. > >Hmmm. I just looked at another machine (i386 running 386/ix) and its >version of those files have no copyright notices in them. This is largely irrelevant. Pieces of Unix are covered by nondisclosure agreements that are part of the licenses. Such agreements do not require any form of notice in the files. (In fact, some readings of the laws at some times in some places have concluded that copyright notices imply publication, which voids nondisclosure agreements!) The license also contains a clause obliging you to make all your users comply with it too, as I recall. -- "The N in NFS stands for Not, | Henry Spencer at U of Toronto Zoology or Need, or perhaps Nightmare"| uunet!attcan!utzoo!henry henry@zoo.toronto.edu