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+
+This is the README for bzip2, a block-sorting file compressor, version
+1.0.  This version is fully compatible with the previous public
+releases, bzip2-0.1pl2, bzip2-0.9.0 and bzip2-0.9.5.
+
+bzip2-1.0 is distributed under a BSD-style license.  For details,
+see the file LICENSE.
+
+Complete documentation is available in Postscript form (manual.ps) or
+html (manual_toc.html).  A plain-text version of the manual page is
+available as bzip2.txt.  A statement about Y2K issues is now included
+in the file Y2K_INFO.
+
+
+HOW TO BUILD -- UNIX
+
+Type `make'.  This builds the library libbz2.a and then the
+programs bzip2 and bzip2recover.  Six self-tests are run.
+If the self-tests complete ok, carry on to installation:
+
+To install in /usr/bin, /usr/lib, /usr/man and /usr/include, type
+   make install
+To install somewhere else, eg, /xxx/yyy/{bin,lib,man,include}, type 
+   make install PREFIX=/xxx/yyy
+If you are (justifiably) paranoid and want to see what 'make install'
+is going to do, you can first do
+   make -n install                      or
+   make -n install PREFIX=/xxx/yyy      respectively.
+The -n instructs make to show the commands it would execute, but
+not actually execute them.
+
+
+HOW TO BUILD -- UNIX, shared library libbz2.so.
+
+Do 'make -f Makefile-libbz2_so'.  This Makefile seems to work for
+Linux-ELF (RedHat 5.2 on an x86 box), with gcc.  I make no claims
+that it works for any other platform, though I suspect it probably
+will work for most platforms employing both ELF and gcc.
+
+bzip2-shared, a client of the shared library, is also build, but
+not self-tested.  So I suggest you also build using the normal
+Makefile, since that conducts a self-test.
+
+Important note for people upgrading .so's from 0.9.0/0.9.5 to
+version 1.0.  All the functions in the library have been renamed,
+from (eg) bzCompress to BZ2_bzCompress, to avoid namespace pollution.
+Unfortunately this means that the libbz2.so created by
+Makefile-libbz2_so will not work with any program which used an
+older version of the library.  Sorry.  I do encourage library
+clients to make the effort to upgrade to use version 1.0, since
+it is both faster and more robust than previous versions.
+
+
+HOW TO BUILD -- Windows 95, NT, DOS, Mac, etc.
+
+It's difficult for me to support compilation on all these platforms.
+My approach is to collect binaries for these platforms, and put them
+on the master web page (http://sourceware.cygnus.com/bzip2).  Look
+there.  However (FWIW), bzip2-1.0 is very standard ANSI C and should
+compile unmodified with MS Visual C.  For Win32, there is one
+important caveat: in bzip2.c, you must set BZ_UNIX to 0 and
+BZ_LCCWIN32 to 1 before building.  If you have difficulties building,
+you might want to read README.COMPILATION.PROBLEMS.
+
+
+VALIDATION
+
+Correct operation, in the sense that a compressed file can always be
+decompressed to reproduce the original, is obviously of paramount
+importance.  To validate bzip2, I used a modified version of Mark
+Nelson's churn program.  Churn is an automated test driver which
+recursively traverses a directory structure, using bzip2 to compress
+and then decompress each file it encounters, and checking that the
+decompressed data is the same as the original.  There are more details
+in Section 4 of the user guide.
+
+
+
+Please read and be aware of the following:
+
+WARNING:
+
+   This program (attempts to) compress data by performing several
+   non-trivial transformations on it.  Unless you are 100% familiar
+   with *all* the algorithms contained herein, and with the
+   consequences of modifying them, you should NOT meddle with the
+   compression or decompression machinery.  Incorrect changes can and
+   very likely *will* lead to disastrous loss of data.
+
+
+DISCLAIMER:
+
+   I TAKE NO RESPONSIBILITY FOR ANY LOSS OF DATA ARISING FROM THE
+   USE OF THIS PROGRAM, HOWSOEVER CAUSED.
+
+   Every compression of a file implies an assumption that the
+   compressed file can be decompressed to reproduce the original.
+   Great efforts in design, coding and testing have been made to
+   ensure that this program works correctly.  However, the complexity
+   of the algorithms, and, in particular, the presence of various
+   special cases in the code which occur with very low but non-zero
+   probability make it impossible to rule out the possibility of bugs
+   remaining in the program.  DO NOT COMPRESS ANY DATA WITH THIS
+   PROGRAM UNLESS YOU ARE PREPARED TO ACCEPT THE POSSIBILITY, HOWEVER
+   SMALL, THAT THE DATA WILL NOT BE RECOVERABLE.
+
+   That is not to say this program is inherently unreliable.  Indeed,
+   I very much hope the opposite is true.  bzip2 has been carefully
+   constructed and extensively tested.
+
+
+PATENTS:
+
+   To the best of my knowledge, bzip2 does not use any patented
+   algorithms.  However, I do not have the resources available to
+   carry out a full patent search.  Therefore I cannot give any
+   guarantee of the above statement.
+
+End of legalities.
+
+
+WHAT'S NEW IN 0.9.0 (as compared to 0.1pl2) ?
+
+   * Approx 10% faster compression, 30% faster decompression
+   * -t (test mode) is a lot quicker
+   * Can decompress concatenated compressed files
+   * Programming interface, so programs can directly read/write .bz2 files
+   * Less restrictive (BSD-style) licensing
+   * Flag handling more compatible with GNU gzip
+   * Much more documentation, i.e., a proper user manual
+   * Hopefully, improved portability (at least of the library)
+
+WHAT'S NEW IN 0.9.5 ?
+
+   * Compression speed is much less sensitive to the input
+     data than in previous versions.  Specifically, the very
+     slow performance caused by repetitive data is fixed.
+   * Many small improvements in file and flag handling.
+   * A Y2K statement.
+
+WHAT'S NEW IN 1.0
+
+   See the CHANGES file.
+
+I hope you find bzip2 useful.  Feel free to contact me at
+   jseward@acm.org
+if you have any suggestions or queries.  Many people mailed me with
+comments, suggestions and patches after the releases of bzip-0.15,
+bzip-0.21, bzip2-0.1pl2 and bzip2-0.9.0, and the changes in bzip2 are
+largely a result of this feedback.  I thank you for your comments.
+
+At least for the time being, bzip2's "home" is (or can be reached via)
+http://www.muraroa.demon.co.uk.
+
+Julian Seward
+jseward@acm.org
+
+Cambridge, UK
+18   July 1996 (version 0.15)
+25 August 1996 (version 0.21)
+ 7 August 1997 (bzip2, version 0.1)
+29 August 1997 (bzip2, version 0.1pl2)
+23 August 1998 (bzip2, version 0.9.0)
+ 8   June 1999 (bzip2, version 0.9.5)
+ 4   Sept 1999 (bzip2, version 0.9.5d)
+ 5    May 2000 (bzip2, version 1.0pre8)