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Merging upstream version 1.6~pre1.

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Signed-off-by: Daniel Baumann <daniel@debian.org>
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Daniel Baumann 2025-02-17 20:32:06 +01:00
parent a9ce1f9ead
commit d98841c4ec
Signed by: daniel
GPG key ID: FBB4F0E80A80222F
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README
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@ -1,10 +1,10 @@
Description
Clzip is a lossless data compressor with a user interface similar to the
one of gzip or bzip2. Clzip decompresses almost as fast as gzip and
compresses more than bzip2, which makes it well suited for software
distribution and data archiving. Clzip is a clean implementation of the
LZMA algorithm.
one of gzip or bzip2. Clzip decompresses almost as fast as gzip,
compresses most files more than bzip2, and is better than both from a
data recovery perspective. Clzip is a clean implementation of the LZMA
algorithm.
Clzip uses the lzip file format; the files produced by clzip are fully
compatible with lzip-1.4 or newer, and can be rescued with lziprecover.
@ -12,17 +12,23 @@ Clzip is in fact a C language version of lzip, intended for embedded
devices or systems lacking a C++ compiler.
The lzip file format is designed for long-term data archiving and
provides very safe integrity checking. The member trailer stores the
32-bit CRC of the original data, the size of the original data and the
size of the member. These values, together with the value remaining in
the range decoder and the end-of-stream marker, provide a 4 factor
integrity checking which guarantees that the decompressed version of the
data is identical to the original. This guards against corruption of the
compressed data, and against undetected bugs in clzip (hopefully very
unlikely). The chances of data corruption going undetected are
microscopic. Be aware, though, that the check occurs upon decompression,
so it can only tell you that something is wrong. It can't help you
recover the original uncompressed data.
provides very safe integrity checking. It is as simple as possible (but
not simpler), 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 lzip is copylefted, which guarantees that it will remain
free forever.
The member trailer stores the 32-bit CRC of the original data, the size
of the original data and the size of the member. These values, together
with the value remaining in the range decoder and the end-of-stream
marker, provide a 4 factor integrity checking which guarantees that the
decompressed version of the data is identical to the original. This
guards against corruption of the compressed data, and against undetected
bugs in clzip (hopefully very unlikely). The chances of data corruption
going undetected are microscopic. Be aware, though, that the check
occurs upon decompression, so it can only tell you that something is
wrong. It can't help you recover the original uncompressed data.
If you ever need to recover data from a damaged lzip file, try the
lziprecover program. Lziprecover makes lzip files resistant to bit-flip
@ -31,15 +37,26 @@ recovery capabilities, including error-checked merging of damaged copies
of a file.
Clzip uses the same well-defined exit status values used by lzip and
bzip2, which makes it safer when used in pipes or scripts than
compressors returning ambiguous warning values, like gzip.
bzip2, which makes it safer than compressors returning ambiguous warning
values (like gzip) when it is used as a back end for tar or zutils.
Clzip replaces every file given in the command line with a compressed
version of itself, with the name "original_name.lz". Each compressed
file has the same modification date, permissions, and, when possible,
ownership as the corresponding original, so that these properties can be
correctly restored at decompression time. Clzip is able to read from some
types of non regular files if the "--stdout" option is specified.
When compressing, clzip replaces every file given in the command line
with a compressed version of itself, with the name "original_name.lz".
When decompressing, clzip 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 clzip
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).
Clzip is able to read from some types of non regular files if the
"--stdout" option is specified.
If no file names are specified, clzip compresses (or decompresses) from
standard input to standard output. In this case, clzip will decline to
@ -81,7 +98,7 @@ range encoding), Igor Pavlov (for putting all the above together in
LZMA), and Julian Seward (for bzip2's CLI).
Copyright (C) 2010, 2011, 2012, 2013 Antonio Diaz Diaz.
Copyright (C) 2010, 2011, 2012, 2013, 2014 Antonio Diaz Diaz.
This file is free documentation: you have unlimited permission to copy,
distribute and modify it.