xz

Compress a file using xz

$ xz [path/to/file]

$ xz --decompress [path/to/file.xz]

$ xz --format=lzma [path/to/file]

$ xz --decompress --format=lzma [path/to/file.lzma]

$ xz --decompress --stdout [path/to/file.xz]

$ xz --keep [path/to/file]

$ xz -0 [path/to/file]

$ xz -9 [path/to/file]

xz [options] [file ...]

-z, --compress
    Compress. This is the default operation mode when decompressing isn't specified explicitly.

-d, --decompress, --uncompress
    Decompress.

-l, --list
    List information about xz archives. Shows header, compressed data, and integrity check sizes.

-t, --test
    Test the integrity of compressed files.

-k, --keep
    Keep (don't delete) input files during compression or decompression.

-f, --force
    Force overwrite of output file and (de)compress even if there are multiple files with the same name.

-c, --stdout, --to-stdout
    Write to standard output.

-q, --quiet
    Suppress warnings; specify twice to suppress errors too.

-v, --verbose
    Be verbose. Give details about the compression ratio, etc.

-T, --threads=num
    Specify the number of threads to use (defaults to 1). Larger numbers can speed up compression on multi-core systems.

-0 ... -9
    Compression level. 0 is fastest, 9 is best. Default is 6.

--version
    Display version information and exit.

--help
    Display help and exit.

The xz command is a general-purpose data compression tool, commonly used on Linux systems. It compresses files using the LZMA2 algorithm, which generally provides a higher compression ratio than gzip or bzip2. The primary use of xz is to reduce the size of files for storage and transmission purposes. It can both compress files to create .xz archives, and decompress them to restore the original data. The xz format has gained popularity in packaging and distribution, especially for software packages and large data sets. Understanding how to use xz is crucial for system administrators, developers, and anyone who frequently handles compressed data on Linux and other Unix-like systems. While xz typically operates on files, it can also work with streams, allowing it to be incorporated into pipelines for real-time compression and decompression tasks.

If the input file has multiple hard links, xz will operate on the first hard link only. The other files pointing to the same underlying data will not be compressed or decompressed.

xz supports different integrity checks like CRC32, CRC64, and SHA-256 to ensure data integrity. The default check is CRC64.

When decompressing a file, xz by default attempts to restore the original filename if it was stored in the archive. The --keep option prevents the original compressed file from being deleted, preserving both the compressed and decompressed versions.

The xz format and command were developed as a replacement for gzip, offering superior compression ratios. It gained prominence as a result of its integration into Linux distributions for package management and system images.

gzip(1), bzip2(1), tar(1)