PLZIP

Section: User Commands (1)
Updated: January 2019
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NAME

plzip - reduces the size of files  

SYNOPSIS

plzip [,options/] [,files/]  

DESCRIPTION

Plzip is a massively parallel (multi-threaded) implementation of lzip, fully compatible with lzip 1.4 or newer. Plzip uses the lzlib compression library.

Lzip is a lossless data compressor with a user interface similar to the one of gzip or bzip2. 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.

Plzip can compress/decompress large files on multiprocessor machines much faster than lzip, at the cost of a slightly reduced compression ratio (0.4 to 2 percent larger compressed files). Note that the number of usable threads is limited by file size; on files larger than a few GB plzip can use hundreds of processors, but on files of only a few MB plzip is no faster than lzip.  

OPTIONS

-h, --help
display this help and exit
-V, --version
output version information and exit
-a, --trailing-error
exit with error status if trailing data
-B, --data-size=<bytes>
set size of input data blocks [2x8=16 MiB]
-c, --stdout
write to standard output, keep input files
-d, --decompress
decompress
-f, --force
overwrite existing output files
-F, --recompress
force re-compression of compressed files
-k, --keep
keep (don't delete) input files
-l, --list
print (un)compressed file sizes
-m, --match-length=<bytes>
set match length limit in bytes [36]
-n, --threads=<n>
set number of (de)compression threads [2]
-o, --output=<file>
if reading standard input, write to <file>
-q, --quiet
suppress all messages
-s, --dictionary-size=<bytes>
set dictionary size limit in bytes [8 MiB]
-t, --test
test compressed file integrity
-v, --verbose
be verbose (a 2nd -v gives more)
-0 .. -9
set compression level [default 6]
--fast
alias for -0
--best
alias for -9
--loose-trailing
allow trailing data seeming corrupt header
--in-slots=<n>
number of 1 MiB input packets buffered [4]
--out-slots=<n>
number of 1 MiB output packets buffered [64]

If no file names are given, or if a file is '-', plzip compresses or decompresses from standard input to standard output. Numbers may be followed by a multiplier: k = kB = 10^3 = 1000, Ki = KiB = 2^10 = 1024, M = 10^6, Mi = 2^20, G = 10^9, Gi = 2^30, etc... Dictionary sizes 12 to 29 are interpreted as powers of two, meaning 2^12 to 2^29 bytes.

The bidimensional parameter space of LZMA can't be mapped to a linear scale optimal for all files. If your files are large, very repetitive, etc, you may need to use the --dictionary-size and --match-length options directly to achieve optimal performance.

Exit status: 0 for a normal exit, 1 for environmental problems (file not found, invalid flags, I/O errors, etc), 2 to indicate a corrupt or invalid input file, 3 for an internal consistency error (eg, bug) which caused plzip to panic.  

REPORTING BUGS

Report bugs to lzip-bug@nongnu.org
Plzip home page: http://www.nongnu.org/lzip/plzip.html  

COPYRIGHT

Copyright © 2009 Laszlo Ersek.
Copyright © 2019 Antonio Diaz Diaz. Using lzlib 1.11 License GPLv2+: GNU GPL version 2 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.  

SEE ALSO

The full documentation for plzip is maintained as a Texinfo manual. If the info and plzip programs are properly installed at your site, the command
info plzip

should give you access to the complete manual.


 

Index

NAME
SYNOPSIS
DESCRIPTION
OPTIONS
REPORTING BUGS
COPYRIGHT
SEE ALSO