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  This is the Info-ZIP file COPYING (for UnZip), last updated 31 Jul 95.
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   There are currently three explicit copyrights on portions of UnZip
   code (at least, of which Info-ZIP is aware):  the original Sam Smith
   copyright on unzip 2.0, upon which Info-ZIP's UnZip 3.0 was based;
   Igor Mandrichenko's copyright on his routines in vms.c; and Greg
   Roelofs' copyright on zipinfo.c and the new version of unshrink.c.
   In addition, Mark Adler has placed inflate.h, inflate.c, explode.c
   and funzip.c into the public domain; i.e., these files may be used
   without any restrictions beyond those of simple courtesy (credit where
   it's due).  All of these are discussed immediately below; the remain-
   ing code is covered by an implicit copyright under US law.  Frequently
   Asked Questions regarding (re)distribution of Zip and UnZip are near
   the end of this file.

   There are no(?) known patents on any of the code in UnZip.  Unisys
   claims a patent on LZW encoding and on LZW decoding _in an apparatus
   which performs LZW encoding_, but a careful reading of the patent
   strongly suggests that a lone decoder (as in UnZip's unshrink.c) is
   not covered.  [Does this also apply to the IBM Miller-Wegman patent?]
   [Is RLE used?  Is Huffman covered by anything?  Is any decoding tech-
   nology covered by anything?]
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   The original unzip source code has been extensively modified and
   almost entirely rewritten (changes include random zipfile access
   rather than sequential; replacement of unimplode() with explode();
   replacement of old unshrink() with new (unrelated) unshrink(); re-
   placement of output routines; addition of inflate(), wildcards,
   filename-mapping, text translation, ...; etc.).  As far as we can
   tell, the only remaining code which is substantially similar to
   Mr. Smith's is that in the file unreduce.c, which now by default
   is NOT compiled.  The following copyright applies to unreduce.c:

     * Copyright 1989 Samuel H. Smith;  All rights reserved
     *
     * Do not distribute modified versions without my permission.
     * Do not remove or alter this notice or any other copyright notice.
     * If you use this in your own program you must distribute source code.
     * Do not use any of this in a commercial product.

   Regarding the first stipulation, Mr. Smith was tracked down in southern
   California some years back [Samuel H. Smith, The Tool Shop; as of mid-
   May 1994, (213) 851-9969 (voice), (213) 887-2127(?) (subscription BBS),
   71150.2731@compuserve.com]:

   "He says that he thought that whoever contacted him understood that
    he has no objection to the Info-ZIP group's inclusion of his code.
    His primary concern is that it remain freely distributable, he said."

   Despite the fact that our "normal" code has been entirely rewritten
   and by default no longer contains any of Mr. Smith's code, Info-ZIP
   remains indebted and grateful to him.  We hope he finds our contribu-
   tions as useful as we have his.

   Note that the third and fourth stipulations still apply to any com-
   pany which wishes to incorporate the unreduce code into its products;
   if you wish to do so, you must contact Mr. Smith directly regarding
   licensing.


   The following copyright applies to most of the VMS code in vms.c,
   distributed with UnZip versions 4.2 and later:

     * Copyright (C) 1992 Igor Mandrichenko.
     * Permission is granted to any individual or institution to use,
     * copy, or redistribute this software so long as all of the orig-
     * inal files are included unmodified, that it is not sold for
     * profit, and that this copyright notice is retained.


   The following copyright applies to the new version of unshrink.c,
   distributed with UnZip versions 5.2 and later:

     * Copyright (C) 1994 Greg Roelofs.
     * Permission is granted to any individual/institution/corporate
     * entity to use, copy, redistribute or modify this software for
     * any purpose whatsoever, subject to the conditions noted in the
     * Frequently Asked Questions section below, plus one additional
     * condition:  namely, that my name not be removed from the source
     * code.  (Other names may, of course, be added as modifications
     * are made.)  Corporate legal staff (like at IBM :-) ) who have
     * problems understanding this can contact me through zip-bugs...


   The remaining code was written by many people associated with the
   Info-ZIP group, with large contributions from (but not limited to):
   Greg Roelofs (overall program logic, ZipInfo, unshrink, filename
   mapping/portability, etc.), Mark Adler (inflate, explode, funzip),
   Kai Uwe Rommel (OS/2), John Bush and Paul Kienitz (Amiga), Antoine
   Verheijen (Macintosh), and Hunter Goatley (more VMS).  See the file
   CONTRIBS in the source distribution for a much more complete list of
   contributors.  As noted above, Mark Adler's inflate.[ch], explode.c
   and funzip.c are in the public domain, and everything which isn't
   otherwise accounted for is implicitly copyrighted by Info-ZIP.  In
   other words, use it with our blessings, but it's still our code.
   Thank you!

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   Frequently Asked Questions about distributing Zip and UnZip:


   Q. Can I distribute Zip and UnZip sources and/or executables?

   A. You may redistribute the latest official distributions without
      any modification, and without even asking us for permission.
      [Note that an "executable distribution" includes documentation,
      even if it's in a separate zipfile; plain executables do NOT
      count.]  You can charge for the cost of the media (CDROM, disk-
      ettes, etc.) and a small copying fee.  Distributed archives
      should follow the naming conventions used in the Where file.
      If you want to distribute modified versions please contact us
      at zip-bugs@wkuvx1.wku.edu first (the final character in the
      hostname is the numeral one, not the letter ell).  You must not
      distribute beta versions without explicit permission to do so.


   Q. Can I use the executables of Zip and UnZip to distribute my
      software?

   A. Yes, so long as it is clear that Zip and UnZip are not being
      sold, that the source code is freely available, and that there
      are no extra or hidden charges resulting from its use by or in-
      clusion with the commercial product.  Here is an example of a
      suitable notice:

         NOTE:  <Product> is packaged on this CD using Info-ZIP's
         compression utility.  The installation program uses UnZip
         to read zip files from the CD.  Info-ZIP's software (Zip,
         UnZip and related utilities) is free and can be obtained
         as source code or executables from various bulletin board
         services and anonymous-ftp sites, including CompuServe's
         IBMPRO forum and ftp.uu.net:/pub/archiving/zip/*.

      If the distribution is being done with UnZipSFX instead of a
      stand-alone copy of UnZip (i.e., as one or more self-extracting
      archives), no notice is required.


   Q. Can I use the source code of Zip and UnZip in my commercial
      application?

   A. Yes, so long as you include in your product an acknowledgment
      and an offer of the original compression sources for free or for
      a small copying fee, and make clear that there are no extra or
      hidden charges resulting from the use of the compression code by
      your product (see below for an example).  The acknowledgment should
      appear in at least one piece of human-readable documentation (e.g.,
      a README file or man page), although additionally putting it in
      the executable(s) is OK, too.  In other words, you are allowed to
      sell only your own work, not ours, and we'd like a little credit.
      [Note the additional restrictions above on the code in unreduce.c,
      unshrink.c and vms.c.]  Contact us at zip-bugs@wkuvx1.wku.edu if
      you have special requirements.  We also like to know when our code
      is being used, but we don't require that.

         <Product> incorporates compression code by the Info-ZIP group.
         There are no extra charges or costs due to the use of this code,
         and the original compression sources are freely available from
         CompuServe in the IBMPRO forum and by anonymous ftp from the
         Internet site ftp.uu.net:/pub/archiving/zip.  We will also, upon
         request, mail you the full sources on a 3.5" MSDOS-format disk-
         ette for the cost of mailing.  Send $2.00 to <address> and ..."

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