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@@ -2,52 +2,60 @@ Description
Lzd is a simplified decompressor for the lzip format with an educational
purpose. Studying its source is a good first step to understand how lzip
-works. It is not safe to use lzd for any real work.
+works.
-The source of lzd is used in the lzip manual as a reference decompressor
-in the description of the lzip file format. Reading the lzip manual will
-help you understand the source.
+The source of lzd is used in the lzip manual as a reference decompressor in
+the description of the lzip file format. Reading the lzip manual will help
+you understand the source. Lzd is compliant with the lzip specification; it
+verifies the 3 integrity factors.
-Lzd decompresses from standard input to standard output. Lzd will
-correctly decompress the concatenation of two or more compressed files.
-The result is the concatenation of the corresponding decompressed data.
-Integrity of such concatenated compressed input is also verified.
+The source of lzd is also used as a reference in the description of the
+media type 'application/lzip'.
+See http://datatracker.ietf.org/doc/draft-diaz-lzip
+
+Lzd decompresses from standard input to standard output. It accepts (and
+ignores) the option '-d' for compatibility with other lzip tools. In
+particular, accepting the option '-d' allows lzd to be used as argument to
+the option '--lz' of the tools from the zutils package.
+
+Lzd will correctly decompress the concatenation of two or more compressed
+files. The result is the concatenation of the corresponding decompressed
+data. Integrity of such concatenated compressed input is also verified.
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.
+ 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.
+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 ideas embodied in lzd 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), and Igor Pavlov (for putting all the above together in
-LZMA).
+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), and Igor Pavlov (for putting all the above together in LZMA).
-Copyright (C) 2013-2019 Antonio Diaz Diaz.
+Copyright (C) 2013-2021 Antonio Diaz Diaz.
This file is free documentation: you have unlimited permission to copy,
-distribute and modify it.
+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