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+This is the file README for the gzip distribution, version 1.2.4.
+
+gzip (GNU zip) is a compression utility designed to be a replacement
+for 'compress'. Its main advantages over compress are much better
+compression and freedom from patented algorithms. The GNU Project
+uses it as the standard compression program for its system.
+
+gzip currently uses by default the LZ77 algorithm used in zip 1.9 (the
+portable pkzip compatible archiver). The gzip format was however
+designed to accommodate several compression algorithms. See below
+for a comparison of zip and gzip.
+
+gunzip can currently decompress files created by gzip, compress or
+pack. The detection of the input format is automatic. For the
+gzip format, gunzip checks a 32 bit CRC. For pack, gunzip checks the
+uncompressed length. The 'compress' format was not designed to allow
+consistency checks. However gunzip is sometimes able to detect a bad
+.Z file because there is some redundancy in the .Z compression format.
+If you get an error when uncompressing a .Z file, do not assume that
+the .Z file is correct simply because the standard uncompress does not
+complain. This generally means that the standard uncompress does not
+check its input, and happily generates garbage output.
+
+gzip produces files with a .gz extension. Previous versions of gzip
+used the .z extension, which was already used by the 'pack'
+Huffman encoder. gunzip is able to decompress .z files (packed
+or gzip'ed).
+
+Several planned features are not yet supported (see the file TODO).
+See the file NEWS for a summary of changes since 0.5. See the file
+INSTALL for installation instructions. Some answers to frequently
+asked questions are given in the file INSTALL, please read it. (In
+particular, please don't ask me once more for an /etc/magic entry.)
+
+WARNING: on several systems, compiler bugs cause gzip to fail, in
+particular when optimization options are on. See the section "Special
+targets" at the end of the INSTALL file for a list of known problems.
+For all machines, use "make check" to check that gzip was compiled
+correctly. Try compiling gzip without any optimization if you have a
+problem.
+
+Please send all comments and bug reports by electronic mail to:
+ Jean-loup Gailly <jloup@chorus.fr>
+
+or, if this fails, to bug-gnu-utils@prep.ai.mit.edu.
+Bug reports should ideally include:
+
+ * The complete output of "gzip -V" (or the contents of revision.h
+ if you can't get gzip to compile)
+ * The hardware and operating system (try "uname -a")
+ * The compiler used to compile (if it is gcc, use "gcc -v")
+ * A description of the bug behavior
+ * The input to gzip, that triggered the bug
+
+If you send me patches for machines I don't have access to, please test them
+very carefully. gzip is used for backups, it must be extremely reliable.
+
+The package crypt++.el is highly recommended to manipulate gzip'ed
+file from emacs. It recognizes automatically encrypted and compressed
+files when they are first visited or written. It is available via
+anonymous ftp to roebling.poly.edu [128.238.5.31] in /pub/crypt++.el.
+The same directory contains also patches to dired, ange-ftp and info.
+GNU tar 1.11.2 has a -z option to invoke directly gzip, so you don't have to
+patch it. The package ftp.uu.net:/languages/emacs-lisp/misc/jka-compr19.el.Z
+also supports gzip'ed files.
+
+The znew and gzexe shell scripts provided with gzip benefit from
+(but do not require) the cpmod utility to transfer file attributes.
+It is available by anonymous ftp on gatekeeper.dec.com in
+/.0/usenet/comp.sources.unix/volume11/cpmod.Z.
+
+The sample programs zread.c, sub.c and add.c in subdirectory sample
+are provided as examples of useful complements to gzip. Read the
+comments inside each source file. The perl script ztouch is also
+provided as example (not installed by default since it relies on perl).
+
+
+gzip is free software, you can redistribute it and/or modify it under
+the terms of the GNU General Public License, a copy of which is
+provided under the name COPYING. The latest version of gzip are always
+available by ftp in prep.ai.mit.edu:/pub/gnu, or in any of the prep
+mirror sites:
+
+- sources in gzip-*.tar (or .shar or .tar.gz).
+- Solaris 2 executables in sparc-sun-solaris2/gzip-binaries-*.tar
+- MSDOS lha self-extracting exe in gzip-msdos-*.exe. Once extracted,
+ copy gzip.exe to gunzip.exe and zcat.exe, or use "gzip -d" to decompress.
+ gzip386.exe runs much faster but only on 386 and above; it is compiled with
+ djgpp 1.10 available in directory omnigate.clarkson.edu:/pub/msdos/djgpp.
+
+A VMS executable is available in ftp.spc.edu:[.macro32.savesets]gzip-1-*.zip
+(use [.macro32]unzip.exe to extract). A PRIMOS executable is available
+in ftp.lysator.liu.se:/pub/primos/run/gzip.run.
+OS/2 executables (16 and 32 bits versions) are available in
+ftp.tu-muenchen.de:/pub/comp/os/os2/archiver/gz*-[16,32].zip
+
+Some ftp servers can automatically make a tar.Z from a tar file. If
+you are getting gzip for the first time, you can ask for a tar.Z file
+instead of the much larger tar file.
+
+Many thanks to those who provided me with bug reports and feedback.
+See the files THANKS and ChangeLog for more details.
+
+
+ Note about zip vs. gzip:
+
+The name 'gzip' was a very unfortunate choice, because zip and gzip
+are two really different programs, although the actual compression and
+decompression sources were written by the same persons. A different
+name should have been used for gzip, but it is too late to change now.
+
+zip is an archiver: it compresses several files into a single archive
+file. gzip is a simple compressor: each file is compressed separately.
+Both share the same compression and decompression code for the
+'deflate' method. unzip can also decompress old zip archives
+(implode, shrink and reduce methods). gunzip can also decompress files
+created by compress and pack. zip 1.9 and gzip do not support
+compression methods other than deflation. (zip 1.0 supports shrink and
+implode). Better compression methods may be added in future versions
+of gzip. zip will always stick to absolute compatibility with pkzip,
+it is thus constrained by PKWare, which is a commercial company. The
+gzip header format is deliberately different from that of pkzip to
+avoid such a constraint.
+
+On Unix, gzip is mostly useful in combination with tar. GNU tar
+1.11.2 has a -z option to invoke gzip automatically. "tar -z"
+compresses better than zip, since gzip can then take advantage of
+redundancy between distinct files. The drawback is that you must
+scan the whole tar.gz file in order to extract a single file near
+the end; unzip can directly seek to the end of the zip file. There
+is no overhead when you extract the whole archive anyway.
+If a member of a .zip archive is damaged, other files can still
+be recovered. If a .tar.gz file is damaged, files beyond the failure
+point cannot be recovered. (Future versions of gzip will have
+error recovery features.)
+
+gzip and gunzip are distributed as a single program. zip and unzip
+are, for historical reasons, two separate programs, although the
+authors of these two programs work closely together in the info-zip
+team. zip and unzip are not associated with the GNU project.
+The sources are available by ftp in
+
+ oak.oakland.edu:/pub/misc/unix/zip19p1.zip
+ oak.oakland.edu:/pub/misc/unix/unz50p1.tar-z
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