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LUNZIP(1) User Commands LUNZIP(1)


lunzip - decompressor for the lzip format


lunzip [options] [files]


Lunzip is a decompressor for the lzip format written in C. Its small size makes it well suited for embedded devices or software installers that need to decompress files but don't need compression capabilities. Lunzip is fully compatible with lzip 1.4 or newer.

Lunzip provides a 'low memory' mode able to decompress any file using as little memory as 50 kB, irrespective of the dictionary size used to compress the file. To activate it, specify the size of the output buffer with the option --buffer-size and lunzip will use the decompressed file as dictionary for distances beyond the buffer size. Of course, the larger the difference between the buffer size and the dictionary size, the more accesses to disk are needed and the slower the decompression is. This 'low memory' mode only works when decompressing to a regular file and is intended for systems without enough memory (RAM + swap) to keep the whole dictionary at once.


display this help and exit
output version information and exit
exit with error status if trailing data
write to standard output, keep input files
decompress (this is the default)
overwrite existing output files
keep (don't delete) input files
print (un)compressed file sizes
write to <file>, keep input files
suppress all messages
test compressed file integrity
set output buffer size in bytes
be verbose (a 2nd -v gives more)
allow trailing data seeming corrupt header

If no file names are given, or if a file is '-', lunzip 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... Buffer sizes 12 to 29 are interpreted as powers of two, meaning 2^12 to 2^29 bytes.

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

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 lunzip to panic.

The ideas embodied in lunzip are due to (at least) the following people: Abraham Lempel and Jacob Ziv (for the LZ algorithm), Andrey Markov (for the definition of Markov chains), G.N.N. Martin (for the definition of range encoding), Igor Pavlov (for putting all the above together in LZMA), and Julian Seward (for bzip2's CLI).


Report bugs to
Lunzip home page:


Copyright © 2021 Antonio Diaz Diaz. License GPLv2+: GNU GPL version 2 or later <>
This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.

January 2021 lunzip 1.12