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3 Invoking lzip

The format for running lzip is:

lzip [options] [files]

Lzip supports the following options:

-h
--help

Print an informative help message describing the options and exit.

-V
--version

Print the version number of lzip on the standard output and exit.

-b bytes
--member-size=bytes

Set the member size limit to bytes. A small member size may degrade compression ratio, so use it only when needed. Valid values range from 100 kB to 64 PiB. Defaults to 64 PiB.

-c
--stdout

Compress or decompress to standard output. Needed when reading from a named pipe (fifo) or from a device. Use it to recover as much of the uncompressed data as possible when decompressing a corrupt file.

-d
--decompress

Decompress.

-f
--force

Force overwrite of output files.

-F
--recompress

Force recompression of files whose name already has the ‘.lz’ or ‘.tlz’ suffix.

-k
--keep

Keep (don’t delete) input files during compression or decompression.

-m bytes
--match-length=bytes

Set the match length limit in bytes. After a match this long is found, the search is finished. Valid values range from 5 to 273. Larger values usually give better compression ratios but longer compression times.

-o file
--output=file

When reading from standard input and ‘--stdout’ has not been specified, use ‘file’ as the virtual name of the uncompressed file. This produces a file named ‘file’ when decompressing, a file named ‘file.lz’ when compressing, and several files named ‘file00001.lz’, ‘file00002.lz’, etc, when compressing and splitting the output in volumes.

-q
--quiet

Quiet operation. Suppress all messages.

-s bytes
--dictionary-size=bytes

Set the dictionary size limit in bytes. Valid values range from 4 KiB to 512 MiB. Lzip will use the smallest possible dictionary size for each member without exceeding this limit. Note that dictionary sizes are quantized. If the specified size does not match one of the valid sizes, it will be rounded upwards by adding up to (bytes / 16) to it.

For maximum compression you should use a dictionary size limit as large as possible, but keep in mind that the decompression memory requirement is affected at compression time by the choice of dictionary size limit.

-S bytes
--volume-size=bytes

Split the compressed output into several volume files with names ‘original_name00001.lz’, ‘original_name00002.lz’, etc, and set the volume size limit to bytes. Each volume is a complete, maybe multi-member, lzip file. A small volume size may degrade compression ratio, so use it only when needed. Valid values range from 100 kB to 4 EiB.

-t
--test

Check integrity of the specified file(s), but don’t decompress them. This really performs a trial decompression and throws away the result. Use it together with ‘-v’ to see information about the file.

-v
--verbose

Verbose mode.
When compressing, show the compression ratio for each file processed. A second ‘-v’ shows the progress of compression.
When decompressing or testing, further -v’s (up to 4) increase the verbosity level, showing status, compression ratio, dictionary size, trailer contents (CRC, data size, member size), and up to 6 bytes of trailing garbage (if any).

-0 .. -9

Set the compression parameters (dictionary size and match length limit) as shown in the table below. Note that ‘-9’ can be much slower than ‘-0’. These options have no effect when decompressing.

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 ‘--match-length’ and ‘--dictionary-size’ options directly to achieve optimal performance. For example, ‘-9m64’ usually compresses executables more (and faster) than ‘-9’.

LevelDictionary sizeMatch length limit
-064 KiB16 bytes
-11 MiB5 bytes
-21.5 MiB6 bytes
-32 MiB8 bytes
-43 MiB12 bytes
-54 MiB20 bytes
-68 MiB36 bytes
-716 MiB68 bytes
-824 MiB132 bytes
-932 MiB273 bytes
--fast
--best

Aliases for GNU gzip compatibility.

Numbers given as arguments to options may be followed by a multiplier and an optional ‘B’ for "byte".

Table of SI and binary prefixes (unit multipliers):

PrefixValue|PrefixValue
kkilobyte (10^3 = 1000)|Kikibibyte (2^10 = 1024)
Mmegabyte (10^6)|Mimebibyte (2^20)
Ggigabyte (10^9)|Gigibibyte (2^30)
Tterabyte (10^12)|Titebibyte (2^40)
Ppetabyte (10^15)|Pipebibyte (2^50)
Eexabyte (10^18)|Eiexbibyte (2^60)
Zzettabyte (10^21)|Zizebibyte (2^70)
Yyottabyte (10^24)|Yiyobibyte (2^80)

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 lzip to panic.


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