Merging upstream version 1.12~rc1.
Signed-off-by: Daniel Baumann <daniel@debian.org>
This commit is contained in:
parent
4ddb634c25
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GPG key ID:
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24 changed files with 874 additions and 719 deletions
doc
359
doc/plzip.texi
359
doc/plzip.texi
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@ -6,8 +6,8 @@
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@finalout
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@c %**end of header
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@set UPDATED 21 January 2024
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@set VERSION 1.11
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@set UPDATED 19 November 2024
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@set VERSION 1.12-rc1
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@dircategory Compression
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@direntry
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@ -36,17 +36,18 @@
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This manual is for Plzip (version @value{VERSION}, @value{UPDATED}).
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@menu
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* Introduction:: Purpose and features of plzip
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* Output:: Meaning of plzip's output
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* Invoking plzip:: Command-line interface
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* Program design:: Internal structure of plzip
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* Memory requirements:: Memory required to compress and decompress
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* Minimum file sizes:: Minimum file sizes required for full speed
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* File format:: Detailed format of the compressed file
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* Trailing data:: Extra data appended to the file
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* Examples:: A small tutorial with examples
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* Problems:: Reporting bugs
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* Concept index:: Index of concepts
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* Introduction:: Purpose and features of plzip
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* Output:: Meaning of plzip's output
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* Invoking plzip:: Command-line interface
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* Argument syntax:: By convention, options start with a hyphen
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* File format:: Detailed format of the compressed file
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* Program design:: Internal structure of plzip
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* Memory requirements:: Memory required to compress and decompress
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* Minimum file sizes:: Minimum file sizes required for full speed
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* Trailing data:: Extra data appended to the file
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* Examples:: A small tutorial with examples
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* Problems:: Reporting bugs
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* Concept index:: Index of concepts
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@end menu
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@sp 1
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@ -61,30 +62,29 @@ distribute, and modify it.
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@chapter Introduction
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@cindex introduction
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@uref{http://www.nongnu.org/lzip/plzip.html,,Plzip}
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is a massively parallel (multi-threaded) implementation of lzip,
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compatible with lzip 1.4 or newer. Plzip uses the compression library
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@uref{http://www.nongnu.org/lzip/plzip.html,,Plzip} is a massively parallel
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(multi-threaded) implementation of lzip. Plzip uses the compression library
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@uref{http://www.nongnu.org/lzip/lzlib.html,,lzlib}.
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@uref{http://www.nongnu.org/lzip/lzip.html,,Lzip}
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is a lossless data compressor with a user interface similar to the one
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of gzip or bzip2. Lzip uses a simplified form of the 'Lempel-Ziv-Markov
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chain-Algorithm' (LZMA) stream format to maximize interoperability. The
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maximum dictionary size is 512 MiB so that any lzip file can be decompressed
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on 32-bit machines. Lzip provides accurate and robust 3-factor integrity
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checking. Lzip can compress about as fast as gzip @w{(lzip -0)} or compress most
|
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files more than bzip2 @w{(lzip -9)}. Decompression speed is intermediate between
|
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gzip and bzip2. Lzip is better than gzip and bzip2 from a data recovery
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||||
perspective. Lzip has been designed, written, and tested with great care to
|
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replace gzip and bzip2 as the standard general-purpose compressed format for
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Unix-like systems.
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of gzip or bzip2. Lzip uses a simplified form of LZMA (Lempel-Ziv-Markov
|
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chain-Algorithm) designed to achieve complete interoperability between
|
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implementations. The maximum dictionary size is 512 MiB so that any lzip
|
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file can be decompressed on 32-bit machines. Lzip provides accurate and
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robust 3-factor integrity checking. @w{@samp{lzip -0}} compresses about as fast as
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gzip, while @w{@samp{lzip -9}} compresses most files more than bzip2. Decompression
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speed is intermediate between gzip and bzip2. Lzip provides better data
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recovery capabilities than gzip and bzip2. Lzip has been designed, written,
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and tested with great care to replace gzip and bzip2 as general-purpose
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compressed format for Unix-like systems.
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|
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Plzip can compress/decompress large files on multiprocessor machines much
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faster than lzip, at the cost of a slightly reduced compression ratio (0.4
|
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to 2 percent larger compressed files). Note that the number of usable
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threads is limited by file size; on files larger than a few GB plzip can use
|
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hundreds of processors, but on files of only a few MB plzip is no faster
|
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than lzip. @xref{Minimum file sizes}.
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hundreds of processors, but on files smaller than @w{1 MiB} plzip is no faster
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than lzip (even at compression level -0). @xref{Minimum file sizes}.
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For creation and manipulation of compressed tar archives
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@uref{http://www.nongnu.org/lzip/manual/tarlz_manual.html,,tarlz} can be more
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@ -132,9 +132,9 @@ makes it safer than compressors returning ambiguous warning values (like
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gzip) when it is used as a back end for other programs like tar or zutils.
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|
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Plzip automatically uses for each file the largest dictionary size that does
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not exceed neither the file size nor the limit given. Keep in mind that the
|
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decompression memory requirement is affected at compression time by the
|
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choice of dictionary size limit. @xref{Memory requirements}.
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not exceed neither the file size nor the limit given. The dictionary size
|
||||
used for decompression is the same dictionary size used for compression.
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@xref{Memory requirements}.
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When compressing, plzip replaces every file given in the command line
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with a compressed version of itself, with the name "original_name.lz".
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@ -235,11 +235,8 @@ argument means standard input. It can be mixed with other @var{files} and is
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read just once, the first time it appears in the command line. Remember to
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prepend @file{./} to any file name beginning with a hyphen, or use @samp{--}.
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plzip supports the following
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@uref{http://www.nongnu.org/arg-parser/manual/arg_parser_manual.html#Argument-syntax,,options}:
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@ifnothtml
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@xref{Argument syntax,,,arg_parser}.
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@end ifnothtml
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@noindent
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plzip supports the following options: @xref{Argument syntax}.
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@table @code
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@item -h
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@ -286,7 +283,8 @@ already exists and @option{--force} has not been specified, plzip continues
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decompressing the rest of the files and exits with error status 1. If a file
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fails to decompress, or is a terminal, plzip exits immediately with error
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status 2 without decompressing the rest of the files. A terminal is
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considered an uncompressed file, and therefore invalid.
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considered an uncompressed file, and therefore invalid. A multimember file
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with one or more empty members is accepted if redirected to standard input.
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@item -f
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@itemx --force
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@ -295,7 +293,7 @@ Force overwrite of output files.
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@item -F
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@itemx --recompress
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When compressing, force re-compression of files whose name already has
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the @samp{.lz} or @samp{.tlz} suffix.
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the @file{.lz} or @file{.tlz} suffix.
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@item -k
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@itemx --keep
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@ -309,7 +307,8 @@ even for multimember files. If more than one file is given, a final line
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|||
containing the cumulative sizes is printed. With @option{-v}, the dictionary
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size, the number of members in the file, and the amount of trailing data (if
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any) are also printed. With @option{-vv}, the positions and sizes of each
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member in multimember files are also printed.
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member in multimember files are also printed. A multimember file with one or
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more empty members is accepted if redirected to standard input.
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If any file is damaged, does not exist, can't be opened, or is not regular,
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the final exit status is @w{> 0}. @option{-lq} can be used to check quickly
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@ -327,7 +326,7 @@ times.
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@item -n @var{n}
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@itemx --threads=@var{n}
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Set the maximum number of worker threads, overriding the system's default.
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Valid values range from 1 to "as many as your system can support". If this
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Valid values range from 1 to as many as your system can support. If this
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option is not used, plzip tries to detect the number of processors in the
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system and use it as default value. When compressing on a @w{32 bit} system,
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plzip tries to limit the memory use to under @w{2.22 GiB} (4 worker threads
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@ -353,10 +352,10 @@ to @option{-c}. @option{-o} has no effect when testing or listing.
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In order to keep backward compatibility with plzip versions prior to 1.9,
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when compressing from standard input and no other file names are given, the
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extension @samp{.lz} is appended to @var{file} unless it already ends in
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@samp{.lz} or @samp{.tlz}. This feature will be removed in a future version
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extension @file{.lz} is appended to @var{file} unless it already ends in
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@file{.lz} or @file{.tlz}. This feature will be removed in a future version
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of plzip. Meanwhile, redirection may be used instead of @option{-o} to write
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||||
the compressed output to a file without the extension @samp{.lz} in its
|
||||
the compressed output to a file without the extension @file{.lz} in its
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name: @w{@samp{plzip < file > foo}}.
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||||
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||||
@item -q
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@ -386,7 +385,8 @@ together with @option{-v} to see information about the files. If a file
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|||
fails the test, does not exist, can't be opened, or is a terminal, plzip
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||||
continues testing the rest of the files. A final diagnostic is shown at
|
||||
verbosity level 1 or higher if any file fails the test when testing multiple
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files.
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files. A multimember file with one or more empty members is accepted if
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||||
redirected to standard input.
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||||
|
||||
@item -v
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@itemx --verbose
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@ -416,7 +416,7 @@ given, the last setting is used. For example @w{@option{-9 -s64MiB}} is
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|||
equivalent to @w{@option{-s64MiB -m273}}
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||||
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||||
@multitable {Level} {Dictionary size (-s)} {Match length limit (-m)}
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||||
@item Level @tab Dictionary size (-s) @tab Match length limit (-m)
|
||||
@headitem Level @tab Dictionary size (-s) @tab Match length limit (-m)
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@item -0 @tab 64 KiB @tab 16 bytes
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@item -1 @tab 1 MiB @tab 5 bytes
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||||
@item -2 @tab 1.5 MiB @tab 6 bytes
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||||
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@ -437,7 +437,7 @@ Aliases for GNU gzip compatibility.
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|||
When decompressing, testing, or listing, allow trailing data whose first
|
||||
bytes are so similar to the magic bytes of a lzip header that they can
|
||||
be confused with a corrupt header. Use this option if a file triggers a
|
||||
"corrupt header" error and the cause is not indeed a corrupt header.
|
||||
'corrupt header' error and the cause is not indeed a corrupt header.
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||||
|
||||
@item --in-slots=@var{n}
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||||
Number of @w{1 MiB} input packets buffered per worker thread when
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@ -474,7 +474,7 @@ and may be followed by a multiplier and an optional @samp{B} for "byte".
|
|||
Table of SI and binary prefixes (unit multipliers):
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||||
|
||||
@multitable {Prefix} {kilobyte (10^3 = 1000)} {|} {Prefix} {kibibyte (2^10 = 1024)}
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||||
@item Prefix @tab Value @tab | @tab Prefix @tab Value
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||||
@headitem Prefix @tab Value @tab | @tab Prefix @tab Value
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||||
@item k @tab kilobyte (10^3 = 1000) @tab | @tab Ki @tab kibibyte (2^10 = 1024)
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||||
@item M @tab megabyte (10^6) @tab | @tab Mi @tab mebibyte (2^20)
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||||
@item G @tab gigabyte (10^9) @tab | @tab Gi @tab gibibyte (2^30)
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||||
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@ -494,6 +494,148 @@ indicate a corrupt or invalid input file, 3 for an internal consistency
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|||
error (e.g., bug) which caused plzip to panic.
|
||||
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||||
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||||
@node Argument syntax
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||||
@chapter Syntax of command-line arguments
|
||||
@cindex argument syntax
|
||||
|
||||
POSIX recommends these conventions for command-line arguments.
|
||||
|
||||
@itemize @bullet
|
||||
@item A command-line argument is an option if it begins with a hyphen
|
||||
(@samp{-}).
|
||||
|
||||
@item Option names are single alphanumeric characters.
|
||||
|
||||
@item Certain options require an argument.
|
||||
|
||||
@item An option and its argument may or may not appear as separate tokens.
|
||||
(In other words, the whitespace separating them is optional, unless the
|
||||
argument is the empty string).
|
||||
Thus, @w{@option{-o foo}} and @option{-ofoo} are equivalent.
|
||||
|
||||
@item One or more options without arguments, followed by at most one option
|
||||
that takes an argument, may follow a hyphen in a single token.
|
||||
Thus, @option{-abc} is equivalent to @w{@option{-a -b -c}}.
|
||||
|
||||
@item Options typically precede other non-option arguments.
|
||||
|
||||
@item The argument @samp{--} terminates all options; any following arguments
|
||||
are treated as non-option arguments, even if they begin with a hyphen.
|
||||
|
||||
@item A token consisting of a single hyphen character is interpreted as an
|
||||
ordinary non-option argument. By convention, it is used to specify standard
|
||||
input, standard output, or a file named @samp{-}.
|
||||
@end itemize
|
||||
|
||||
@noindent
|
||||
GNU adds @dfn{long options} to these conventions:
|
||||
|
||||
@itemize @bullet
|
||||
@item A long option consists of two hyphens (@samp{--}) followed by a name
|
||||
made of alphanumeric characters and hyphens. Option names are typically one
|
||||
to three words long, with hyphens to separate words. Abbreviations can be
|
||||
used for the long option names as long as the abbreviations are unique.
|
||||
|
||||
@item A long option and its argument may or may not appear as separate
|
||||
tokens. In the latter case they must be separated by an equal sign @samp{=}.
|
||||
Thus, @w{@option{--foo bar}} and @option{--foo=bar} are equivalent.
|
||||
@end itemize
|
||||
|
||||
@noindent
|
||||
The syntax of options with an optional argument is
|
||||
@option{-<short_option><argument>} (without whitespace), or
|
||||
@option{--<long_option>=<argument>}.
|
||||
|
||||
|
||||
@node File format
|
||||
@chapter File format
|
||||
@cindex file format
|
||||
|
||||
Perfection is reached, not when there is no longer anything to add, but
|
||||
when there is no longer anything to take away.@*
|
||||
--- Antoine de Saint-Exupery
|
||||
|
||||
In the diagram below, a box like this:
|
||||
|
||||
@verbatim
|
||||
+---+
|
||||
| | <-- the vertical bars might be missing
|
||||
+---+
|
||||
@end verbatim
|
||||
|
||||
represents one byte; a box like this:
|
||||
|
||||
@verbatim
|
||||
+==============+
|
||||
| |
|
||||
+==============+
|
||||
@end verbatim
|
||||
|
||||
represents a variable number of bytes.
|
||||
|
||||
@noindent
|
||||
A lzip file consists of one or more independent "members" (compressed data
|
||||
sets). The members simply appear one after another in the file, with no
|
||||
additional information before, between, or after them. Each member can
|
||||
encode in compressed form up to @w{16 EiB - 1 byte} of uncompressed data.
|
||||
The size of a multimember file is unlimited. Empty members (data size = 0)
|
||||
are not allowed in multimember files.
|
||||
|
||||
Each member has the following structure:
|
||||
|
||||
@verbatim
|
||||
+--+--+--+--+----+----+=============+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
||||
| ID string | VN | DS | LZMA stream | CRC32 | Data size | Member size |
|
||||
+--+--+--+--+----+----+=============+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
||||
@end verbatim
|
||||
|
||||
All multibyte values are stored in little endian order.
|
||||
|
||||
@table @samp
|
||||
@item ID string (the "magic" bytes)
|
||||
A four byte string, identifying the lzip format, with the value "LZIP"
|
||||
(0x4C, 0x5A, 0x49, 0x50).
|
||||
|
||||
@item VN (version number, 1 byte)
|
||||
Just in case something needs to be modified in the future. 1 for now.
|
||||
|
||||
@anchor{coded-dict-size}
|
||||
@item DS (coded dictionary size, 1 byte)
|
||||
The dictionary size is calculated by taking a power of 2 (the base size)
|
||||
and subtracting from it a fraction between 0/16 and 7/16 of the base size.@*
|
||||
Bits 4-0 contain the base 2 logarithm of the base size (12 to 29).@*
|
||||
Bits 7-5 contain the numerator of the fraction (0 to 7) to subtract
|
||||
from the base size to obtain the dictionary size.@*
|
||||
Example: 0xD3 = 2^19 - 6 * 2^15 = 512 KiB - 6 * 32 KiB = 320 KiB@*
|
||||
Valid values for dictionary size range from 4 KiB to 512 MiB.
|
||||
|
||||
@item LZMA stream
|
||||
The LZMA stream, terminated by an 'End Of Stream' marker. Uses default values
|
||||
for encoder properties.
|
||||
@ifnothtml
|
||||
@xref{Stream format,,,lzip},
|
||||
@end ifnothtml
|
||||
@ifhtml
|
||||
See
|
||||
@uref{http://www.nongnu.org/lzip/manual/lzip_manual.html#Stream-format,,Stream format}
|
||||
@end ifhtml
|
||||
for a complete description.
|
||||
|
||||
@item CRC32 (4 bytes)
|
||||
Cyclic Redundancy Check (CRC) of the original uncompressed data.
|
||||
|
||||
@item Data size (8 bytes)
|
||||
Size of the original uncompressed data.
|
||||
|
||||
@item Member size (8 bytes)
|
||||
Total size of the member, including header and trailer. This field acts
|
||||
as a distributed index, improves the checking of stream integrity, and
|
||||
facilitates the safe recovery of undamaged members from multimember files.
|
||||
Lzip limits the member size to @w{2 PiB} to prevent the data size field from
|
||||
overflowing.
|
||||
@end table
|
||||
|
||||
|
||||
@node Program design
|
||||
@chapter Internal structure of plzip
|
||||
@cindex program design
|
||||
|
|
@ -510,8 +652,8 @@ because lzip usually produces single-member files, which can't be
|
|||
decompressed in parallel.
|
||||
|
||||
For each input file, a splitter thread and several worker threads are
|
||||
created, acting the main thread as muxer (multiplexer) thread. A "packet
|
||||
courier" takes care of data transfers among threads and limits the
|
||||
created, acting the main thread as muxer (multiplexer) thread. A 'packet
|
||||
courier' takes care of data transfers among threads and limits the
|
||||
maximum number of data blocks (packets) being processed simultaneously.
|
||||
|
||||
The splitter reads data blocks from the input file, and distributes them
|
||||
|
|
@ -587,7 +729,7 @@ The following table shows the memory required @strong{per thread} for
|
|||
compression at a given level, using the default data size for each level:
|
||||
|
||||
@multitable {Level} {Memory required}
|
||||
@item Level @tab Memory required
|
||||
@headitem Level @tab Memory required
|
||||
@item -0 @tab 4.875 MiB
|
||||
@item -1 @tab 17.75 MiB
|
||||
@item -2 @tab 26.625 MiB
|
||||
|
|
@ -638,96 +780,6 @@ data size for each level:
|
|||
@end multitable
|
||||
|
||||
|
||||
@node File format
|
||||
@chapter File format
|
||||
@cindex file format
|
||||
|
||||
Perfection is reached, not when there is no longer anything to add, but
|
||||
when there is no longer anything to take away.@*
|
||||
--- Antoine de Saint-Exupery
|
||||
|
||||
@sp 1
|
||||
In the diagram below, a box like this:
|
||||
|
||||
@verbatim
|
||||
+---+
|
||||
| | <-- the vertical bars might be missing
|
||||
+---+
|
||||
@end verbatim
|
||||
|
||||
represents one byte; a box like this:
|
||||
|
||||
@verbatim
|
||||
+==============+
|
||||
| |
|
||||
+==============+
|
||||
@end verbatim
|
||||
|
||||
represents a variable number of bytes.
|
||||
|
||||
@sp 1
|
||||
A lzip file consists of one or more independent "members" (compressed data
|
||||
sets). The members simply appear one after another in the file, with no
|
||||
additional information before, between, or after them. Each member can
|
||||
encode in compressed form up to @w{16 EiB - 1 byte} of uncompressed data.
|
||||
The size of a multimember file is unlimited.
|
||||
|
||||
Each member has the following structure:
|
||||
|
||||
@verbatim
|
||||
+--+--+--+--+----+----+=============+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
||||
| ID string | VN | DS | LZMA stream | CRC32 | Data size | Member size |
|
||||
+--+--+--+--+----+----+=============+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
||||
@end verbatim
|
||||
|
||||
All multibyte values are stored in little endian order.
|
||||
|
||||
@table @samp
|
||||
@item ID string (the "magic" bytes)
|
||||
A four byte string, identifying the lzip format, with the value "LZIP"
|
||||
(0x4C, 0x5A, 0x49, 0x50).
|
||||
|
||||
@item VN (version number, 1 byte)
|
||||
Just in case something needs to be modified in the future. 1 for now.
|
||||
|
||||
@anchor{coded-dict-size}
|
||||
@item DS (coded dictionary size, 1 byte)
|
||||
The dictionary size is calculated by taking a power of 2 (the base size)
|
||||
and subtracting from it a fraction between 0/16 and 7/16 of the base size.@*
|
||||
Bits 4-0 contain the base 2 logarithm of the base size (12 to 29).@*
|
||||
Bits 7-5 contain the numerator of the fraction (0 to 7) to subtract
|
||||
from the base size to obtain the dictionary size.@*
|
||||
Example: 0xD3 = 2^19 - 6 * 2^15 = 512 KiB - 6 * 32 KiB = 320 KiB@*
|
||||
Valid values for dictionary size range from 4 KiB to 512 MiB.
|
||||
|
||||
@item LZMA stream
|
||||
The LZMA stream, finished by an "End Of Stream" marker. Uses default values
|
||||
for encoder properties.
|
||||
@ifnothtml
|
||||
@xref{Stream format,,,lzip},
|
||||
@end ifnothtml
|
||||
@ifhtml
|
||||
See
|
||||
@uref{http://www.nongnu.org/lzip/manual/lzip_manual.html#Stream-format,,Stream format}
|
||||
@end ifhtml
|
||||
for a complete description.
|
||||
|
||||
@item CRC32 (4 bytes)
|
||||
Cyclic Redundancy Check (CRC) of the original uncompressed data.
|
||||
|
||||
@item Data size (8 bytes)
|
||||
Size of the original uncompressed data.
|
||||
|
||||
@item Member size (8 bytes)
|
||||
Total size of the member, including header and trailer. This field acts
|
||||
as a distributed index, improves the checking of stream integrity, and
|
||||
facilitates the safe recovery of undamaged members from multimember files.
|
||||
Lzip limits the member size to @w{2 PiB} to prevent the data size field from
|
||||
overflowing.
|
||||
|
||||
@end table
|
||||
|
||||
|
||||
@node Trailing data
|
||||
@chapter Extra data appended to the file
|
||||
@cindex trailing data
|
||||
|
|
@ -742,7 +794,7 @@ example when writing to a tape. It is safe to append any amount of
|
|||
padding zero bytes to a lzip file.
|
||||
|
||||
@item
|
||||
Useful data added by the user; an "End Of File" string (to check that the
|
||||
Useful data added by the user; an 'End Of File' string (to check that the
|
||||
file has not been truncated), a cryptographically secure hash, a description
|
||||
of file contents, etc. It is safe to append any amount of text to a lzip
|
||||
file as long as none of the first four bytes of the text matches the
|
||||
|
|
@ -794,9 +846,8 @@ compression can only be detected by comparing the compressed file with the
|
|||
original because the corruption happens before plzip compresses the RAM
|
||||
contents, resulting in a valid compressed file containing wrong data.
|
||||
|
||||
@sp 1
|
||||
@noindent
|
||||
Example 1: Extract all the files from archive @samp{foo.tar.lz}.
|
||||
Example 1: Extract all the files from archive @file{foo.tar.lz}.
|
||||
|
||||
@example
|
||||
tar -xf foo.tar.lz
|
||||
|
|
@ -804,43 +855,38 @@ or
|
|||
plzip -cd foo.tar.lz | tar -xf -
|
||||
@end example
|
||||
|
||||
@sp 1
|
||||
@noindent
|
||||
Example 2: Replace a regular file with its compressed version @samp{file.lz}
|
||||
Example 2: Replace a regular file with its compressed version @file{file.lz}
|
||||
and show the compression ratio.
|
||||
|
||||
@example
|
||||
plzip -v file
|
||||
@end example
|
||||
|
||||
@sp 1
|
||||
@noindent
|
||||
Example 3: Like example 2 but the created @samp{file.lz} has a block size of
|
||||
Example 3: Like example 2 but the created @file{file.lz} has a block size of
|
||||
@w{1 MiB}. The compression ratio is not shown.
|
||||
|
||||
@example
|
||||
plzip -B 1MiB file
|
||||
@end example
|
||||
|
||||
@sp 1
|
||||
@noindent
|
||||
Example 4: Restore a regular file from its compressed version
|
||||
@samp{file.lz}. If the operation is successful, @samp{file.lz} is removed.
|
||||
@file{file.lz}. If the operation is successful, @file{file.lz} is removed.
|
||||
|
||||
@example
|
||||
plzip -d file.lz
|
||||
@end example
|
||||
|
||||
@sp 1
|
||||
@noindent
|
||||
Example 5: Check the integrity of the compressed file @samp{file.lz} and
|
||||
Example 5: Check the integrity of the compressed file @file{file.lz} and
|
||||
show status.
|
||||
|
||||
@example
|
||||
plzip -tv file.lz
|
||||
@end example
|
||||
|
||||
@sp 1
|
||||
@anchor{concat-example}
|
||||
@noindent
|
||||
Example 6: The right way of concatenating the decompressed output of two or
|
||||
|
|
@ -853,28 +899,25 @@ Do this instead
|
|||
plzip -cd file1.lz file2.lz file3.lz
|
||||
@end example
|
||||
|
||||
@sp 1
|
||||
@noindent
|
||||
Example 7: Decompress @samp{file.lz} partially until @w{10 KiB} of
|
||||
Example 7: Decompress @file{file.lz} partially until @w{10 KiB} of
|
||||
decompressed data are produced.
|
||||
|
||||
@example
|
||||
plzip -cd file.lz | dd bs=1024 count=10
|
||||
@end example
|
||||
|
||||
@sp 1
|
||||
@noindent
|
||||
Example 8: Decompress @samp{file.lz} partially from decompressed byte at
|
||||
Example 8: Decompress @file{file.lz} partially from decompressed byte at
|
||||
offset 10000 to decompressed byte at offset 14999 (5000 bytes are produced).
|
||||
|
||||
@example
|
||||
plzip -cd file.lz | dd bs=1000 skip=10 count=5
|
||||
@end example
|
||||
|
||||
@sp 1
|
||||
@noindent
|
||||
Example 9: Compress a whole device in /dev/sdc and send the output to
|
||||
@samp{file.lz}.
|
||||
@file{file.lz}.
|
||||
|
||||
@example
|
||||
plzip -c /dev/sdc > file.lz
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue