    Description

    Lzlib is a data compression library providing in-memory LZMA compression
    and decompression functions, including integrity checking of the
    decompressed data. The compressed data format used by the library is the
    lzip format. Lzlib is written in C.

    The lzip file format is designed for data sharing and long-term
    archiving, taking into account both data integrity and decoder
    availability:

       * The lzip format provides very safe integrity checking and some data
         recovery means. The lziprecover program can repair bit-flip errors
         (one of the most common forms of data corruption) in lzip files,
         and provides data recovery capabilities, including error-checked
         merging of damaged copies of a file.

       * The lzip format is as simple as possible (but not simpler). The
         lzip manual provides the source code of a simple decompressor along
         with a detailed explanation of how it works, so that with the only
         help of the lzip manual it would be possible for a digital
         archaeologist to extract the data from a lzip file long after
         quantum computers eventually render LZMA obsolete.

       * Additionally the lzip reference implementation is copylefted, which
         guarantees that it will remain free forever.

    A nice feature of the lzip format is that a corrupt byte is easier to
    repair the nearer it is from the beginning of the file. Therefore, with
    the help of lziprecover, losing an entire archive just because of a
    corrupt byte near the beginning is a thing of the past.

    The functions and variables forming the interface of the compression
    library are declared in the file 'lzlib.h'. Usage examples of the
    library are given in the files 'main.c' and 'bbexample.c' from the
    source distribution.

    Compression/decompression is done by repeatedly calling a couple of
    read/write functions until all the data have been processed by the
    library. This interface is safer and less error prone than the
    traditional zlib interface.

    Compression/decompression is done when the read function is called. This
    means the value returned by the position functions will not be updated
    until a read call, even if a lot of data are written. If you want the
    data to be compressed in advance, just call the read function with a
    size equal to 0.

    If all the data to be compressed are written in advance, lzlib will
    automatically adjust the header of the compressed data to use the
    smallest possible dictionary size. This feature reduces the amount of
    memory needed for decompression and allows minilzip to produce identical
    compressed output as lzip.

    Lzlib will correctly decompress a data stream which is the concatenation
    of two or more compressed data streams. The result is the concatenation
    of the corresponding decompressed data streams. Integrity testing of
    concatenated compressed data streams is also supported.

    All the library functions are thread safe. The library does not install
    any signal handler. The decoder checks the consistency of the compressed
    data, so the library should never crash even in case of corrupted input.

    In spite of its name (Lempel-Ziv-Markov chain-Algorithm), LZMA is not a
    concrete algorithm; it is more like "any algorithm using the LZMA coding
    scheme". For example, the option '-0' of lzip uses the scheme in almost
    the simplest way possible; issuing the longest match it can find, or a
    literal byte if it can't find a match. Inversely, a much more elaborated
    way of finding coding sequences of minimum size than the one currently
    used by lzip could be developed, and the resulting sequence could also
    be coded using the LZMA coding scheme.

    Lzlib currently implements two variants of the LZMA algorithm; fast
    (used by option '-0' of minilzip) and normal (used by all other
    compression levels).

    The high compression of LZMA comes from combining two basic, well-proven
    compression ideas: sliding dictionaries (LZ77/78) and markov models (the
    thing used by every compression algorithm that uses a range encoder or
    similar order-0 entropy coder as its last stage) with segregation of
    contexts according to what the bits are used for.

    The ideas embodied in lzlib are due to (at least) the following people:
    Abraham Lempel and Jacob Ziv (for the LZ algorithm), Andrey Markov (for
    the definition of Markov chains), G.N.N. Martin (for the definition of
    range encoding), Igor Pavlov (for putting all the above together in
    LZMA), and Julian Seward (for bzip2's CLI).

    Copyright (C) 2009-2017 Antonio Diaz Diaz.

    This file is free documentation: you have unlimited permission to copy,
    distribute and modify it.

    The file Makefile.in is a data file used by configure to produce the
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