Tribblix: manual page: plzip.1

PLZIP(1) User Commands PLZIP(1)

NAME

plzip - reduces the size of files

SYNOPSIS

plzip [options] [files]

DESCRIPTION

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

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 to maximize
interoperability. The maximum dictionary size is 512 MiB so that any
lzip file can be decompressed on 32-bit machines. Lzip provides
accurate and robust 3-factor integrity checking. 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, test compressed file integrity

-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>
write to <file>, keep input files

-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]

--check-lib
compare version of lzlib.h with liblz.{a,so}

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 options --dictionary-size
and --match-length directly to achieve optimal performance.

To extract all the files from archive 'foo.tar.lz', use the commands
'tar -xf foo.tar.lz' or 'plzip -cd foo.tar.lz | tar -xf -'.

Exit status: 0 for a normal exit, 1 for environmental problems (file
not found, invalid command-line options, I/O errors, etc), 2 to
indicate a corrupt or invalid input file, 3 for an internal
consistency error (e.g., 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

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