Adding upstream version 1.23.upstream/1.23upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

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+Description
+
+Lzip is a lossless data compressor with a user interface similar to the one
+of gzip or bzip2. Lzip uses a simplified form of the 'Lempel-Ziv-Markov
+chain-Algorithm' (LZMA) stream format and provides a 3 factor integrity
+checking to maximize interoperability and optimize safety. Lzip can compress
+about as fast as gzip (lzip -0) or compress most files more than bzip2
+(lzip -9). Decompression speed is intermediate between gzip and bzip2.
+Lzip is better than gzip and bzip2 from a data recovery perspective. Lzip
+has been designed, written, and tested with great care to replace gzip and
+bzip2 as the standard general-purpose compressed format for unix-like
+systems.
+
+For compressing/decompressing large files on multiprocessor machines plzip
+can be much faster than lzip at the cost of a slightly reduced compression
+ratio.
+
+For creation and manipulation of compressed tar archives tarlz can be more
+efficient than using tar and plzip because tarlz is able to keep the
+alignment between tar members and lzip members.
+
+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 program lziprecover 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.
+
+Lzip uses the same well-defined exit status values used by bzip2, which
+makes it safer than compressors returning ambiguous warning values (like
+gzip) when it is used as a back end for other programs like tar or zutils.
+
+Lzip will automatically use for each file the largest dictionary size that
+does not exceed neither the file size nor the limit given. Keep in mind that
+the decompression memory requirement is affected at compression time by the
+choice of dictionary size limit.
+
+The amount of memory required for compression is about 1 or 2 times the
+dictionary size limit (1 if input file size is less than dictionary size
+limit, else 2) plus 9 times the dictionary size really used. The option '-0'
+is special and only requires about 1.5 MiB at most. The amount of memory
+required for decompression is about 46 kB larger than the dictionary size
+really used.
+
+When compressing, lzip replaces every file given in the command line
+with a compressed version of itself, with the name "original_name.lz".
+When decompressing, lzip attempts to guess the name for the decompressed
+file from that of the compressed file as follows:
+
+filename.lz    becomes   filename
+filename.tlz   becomes   filename.tar
+anyothername   becomes   anyothername.out
+
+(De)compressing a file is much like copying or moving it. Therefore lzip
+preserves the access and modification dates, permissions, and, when
+possible, ownership of the file just as 'cp -p' does. (If the user ID or
+the group ID can't be duplicated, the file permission bits S_ISUID and
+S_ISGID are cleared).
+
+Lzip is able to read from some types of non-regular files if either the
+option '-c' or the option '-o' is specified.
+
+If no file names are specified, lzip compresses (or decompresses) from
+standard input to standard output. Lzip will refuse to read compressed data
+from a terminal or write compressed data to a terminal, as this would be
+entirely incomprehensible and might leave the terminal in an abnormal state.
+
+Lzip will correctly decompress a file which is the concatenation of two or
+more compressed files. The result is the concatenation of the corresponding
+decompressed files. Integrity testing of concatenated compressed files is
+also supported.
+
+Lzip can produce multimember files, and lziprecover can safely recover the
+undamaged members in case of file damage. Lzip can also split the compressed
+output in volumes of a given size, even when reading from standard input.
+This allows the direct creation of multivolume compressed tar archives.
+
+Lzip is able to compress and decompress streams of unlimited size by
+automatically creating multimember output. The members so created are large,
+about 2 PiB each.
+
+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.
+
+Lzip currently implements two variants of the LZMA algorithm: fast
+(used by option '-0') 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 lzip 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).
+
+LANGUAGE NOTE: Uncompressed = not compressed = plain data; it may never have
+been compressed. Decompressed is used to refer to data which have undergone
+the process of decompression.
+
+
+Copyright (C) 2008-2022 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
+Makefile. It has the same copyright owner and permissions that configure
+itself.