This is the README file for the 28 August 1994 public release of the
Info-ZIP group's portable UnZip zipfile-extraction program (and related
utilities).

unzip512.zip	portable UnZip, version 5.12, source code distribution
unzip512.tar.Z	same as above, but compress'd tar format

__________________________________________________________________________

BEFORE YOU ASK:  UnZip, its companion utility Zip, and related utilities
and support files can be found in many places; read the file "Where" for
further details.  To contact the authors with suggestions, bug reports,
or fixes, continue reading this file (README) and, if this is part of a
source distribution, the file "ZipPorts".  Also in source distributions:
read "BUGS" for a list of known bugs, non-bugs and possible future bugs;
INSTALL for instructions on how to build UnZip; and "Contents" for a com-
mented listing of all the distributed files.

ALSO NOTE:  Info-ZIP's mailing addresses changed between UnZip 5.0p1 and
5.1 releases (and since Zip 2.0.1)!  The old BITNET address doesn't even
exist anymore.  See below.
__________________________________________________________________________


GENERAL INFO
------------
UnZip is an extraction utility for archives compressed in .zip format (also
called "zipfiles").  Although highly compatible both with PKWARE's PKZIP 
and PKUNZIP utilities for MS-DOS and with Info-ZIP's own Zip program, our
primary objectives have been portability and non-MSDOS functionality.

This version of UnZip has been ported to a wide array of hardware--from 
micros to supercomputers--and operating systems:  Unix (many flavors),
VMS, OS/2, MSDOS (+ Windows), NT, TOPS-20 (partly), AmigaDOS, Atari TOS,
Macintosh and Human68k.  UnZip features not found in PKUNZIP include source
code; default extraction of directory trees (with a switch to defeat this, 
rather than the reverse); VMS, Macintosh and OS/2 extended file attributes; 
and, of course, the ability to run under most of your favorite operating 
systems.  Plus, it's free. :-)

For source distributions, see the main Contents file for a list of what's
included, and read INSTALL for instructions on compiling (including OS-
specific comments).  The individual operating systems' Contents files (for 
example, vms/Contents) may list important compilation info in addition to 
explaining what files are what, so be sure to read them.  Some of the ports 
have their own, special README files, so be sure to look for those, too.

See unzip.1 or unzip.doc for usage (or the corresponding UnZipSFX, ZipInfo
and fUnZip docs).  For VMS, unzip_def.rnh or unzip_cli.help may be compiled
into unzip.hlp and installed as a normal VMS help entry; see vms/descrip.mms.


CHANGES AND NEW FEATURES
------------------------
The 5.12 release mainly fixes some bugs in 5.11, including a silly pointer
error in unzipsfx.  The only new features are fairly minor:

   - ZipInfo check for dead space inside archives (PKZIP/Netware bug)
   - SFX_EXDIR compilation option to allow -d <exdir> with UnZipSFX
   - "unzip -vqqqq" prints just the version number (e.g., "512")

Since neither 5.11 nor 5.1 was posted to Usenet, here's a summary of their
new features.  In UnZip 5.11:

   - UnZipSFX, a self-extraction stub for prepending to (new-style) zipfiles
      (tested under Unix, VMS, MS-DOS, OS/2, etc.; NOT portable *across* OSes)
   - unshrink() rewritten to avoid copyright problems; 32-bit version only
   - strings moved to far memory in MS-DOS:  can use small model again (MSC)
   - numerous customization options (see INSTALL)
   - diagnostic screen with -v option and no zipfile (i.e., "unzip -v")
   - -C option for case-insensitive filename matching (esp. for MS-DOS, OS/2)
   - more bad-zipfile "intelligence" (can sometimes even extract concatenated
      multi-part archives)
   - former -U behavior is now the default; new -L option to provide what was
      the default behavior (auto-conversion of uppercase-OS filenames to lower
      case)
   - ZipInfo -T option to print times in decimal format (yymmdd.hhmmss) for
      piping into sort(1)
   - performance tweaks for listing archive contents
   - improved/expanded documentation, esp. man pages (*.doc files) and INSTALL

In UnZip 5.1:

   - wildcard zipfiles (e.g., "unzip -tq \*.zip")
   - extract to a directory other than the current one (-d <exdir> option)
   - auto-conversion of text files
   - ANSI sequences disabled in comments and filenames (avoid "ANSI bombs")
   - ZipInfo incorporated into UnZip (-Z option)
   - full Amiga, Atari, Mac, NT and Human68K support (partial TOPS-20)
   - performance tuning for 35-70% faster extraction (depends on compression
      method)

Note that, according to one tester, the 32-bit MS-DOS version is now *faster*
than PKUNZIP on most archives!  Cool.


DISTRIBUTION
------------
If you have a question regarding redistribution of Info-ZIP software,
either as-is, as packaging for a commercial product, or as an integral
part of a commercial product, read the Frequently Asked Questions (FAQ)
section of the included COPYING file.

Insofar as C compilers are rare on some platforms and the authors only
have direct access to Unix, VMS, OS/2, MS-DOS, Mac, Amiga and Atari 
systems, others may wish to provide ready-to-run executables for new
systems.  In general there is no problem with this; we require only that 
such distributions include this README file, the Where file, the COPYING 
file (contains copyright/redistribution information), and the appropriate 
documentation files (unzip.doc and/or unzip.1 for UnZip, etc.).  If the 
local system provides a way to make self-extracting archives in which both 
the executables and text files may be stored together, that is best (in
particular, use UnZipSFX if at all possible, even if it's a few kilobytes
bigger than the alternatives); otherwise we suggest a bare UnZip executable
and a separate zipfile containing the remaining text and binary files.  If
another archiving method is in common use on the target system (for example,
Zoo or LHa), that may also be used.


BUGS AND NEW PORTS:  CONTACTING INFO-ZIP
----------------------------------------
All bug reports and patches (context diffs only, please!) should go to 
[email protected], which is the e-mail address for the Info-ZIP
authors.  "Dumb questions" which aren't adequately answered in the docu-
mentation should also be directed here rather than to a global forum such
as Usenet.  (Kindly make certain that your questions *isn't* answered by
the documentation, however--a great deal of effort has gone into making
it clear and complete.)  Suggestions for new features can be sent to
[email protected], a mailing list for the Info-ZIP beta testers, 
for discussion (the authors hang out here as well, of course), although 
we don't promise to act on all suggestions.  If it is something which is 
manifestly useful, sending the required patches to zip-bugs directly (as
per the instructions in the ZipPorts file) is likely to produce a quicker 
response than asking us to do it--the authors are always somewhat short 
on time.  (Please do NOT send patches or encoded zipfiles to the info-zip 
address.)

If you are considering a port, not only should you read the ZipPorts file,
but also please check in with zip-bugs BEFORE getting started, since the 
code is constantly being updated behind the scenes.  For example, an Acorn/
Archimedes port is already almost complete, as is an OS/2 dynamic link lib-
rary (DLL) version; VMOS, VM/CMS, Netware, QDOS and NT DLL ports are claimed
to be under construction, although we have yet to see any up-to-date patches.
We will arrange to send you the latest sources.  The alternative is the pos-
sibility that your hard work will be tucked away in a sub-archive and mostly
ignored, or completely ignored if someone else has already done the port
(and you'd be surprised how often this has happened).  IBM mainframe ports
(VM/CMS and/or MVS) would be particularly welcome.  (It can't be *that* hard,
folks...the VMS filesystem is similar in many ways.)


BETA TESTING:  JOINING INFO-ZIP
-------------------------------
If you'd like to keep up to date with our UnZip (and companion Zip utility)
development, join the ranks of beta testers, add your own thoughts and con-
tributions, etc., send a two-line mail message containing the commands HELP
and LIST (on separate lines in the body of the message, not on the subject
line) to [email protected].  You'll receive two messages listing the 
various Info-ZIP mailing-list formats which are available (and also various
unrelated lists) and instructions on how to subscribe to one or more of them
(courtesy of Hunter Goatley).  As of mid-1994, subscribing to the announce-
ments list requires a command of the form

	SUBSCRIBE Info-ZIP-announce "Joe Isuzu"

The discussion list is called either Info-ZIP or Info-ZIP-digest, depending
on one's preference for delivery.


-- Greg Roelofs (Cave Newt), UnZip maintainer/container/explainer and
   developer guy, with inspiration from David Kirschbaum