since version 5.4.0 threaded decompression has been implemented. Xz has supported multi-threaded compression (with the -T flag) since 2014, version 5.2.0. Tar xJf keep.txz # decompress then extract the file. Tar cJf keep.txz keep # archive then compress the directory. Single-letter tar example for archive with compress and decompress with extract using short suffix: Tar -x -lzma -f my_ # results in /some_directory Tar -x -xz -f my_ # results in /some_directory Tar -c -lzma -f my_ /some_directory # results in my_ĭecompressing the archive and extracting its contents: Tar -c -xz -f my_ /some_directory # results in my_ Version 1.22 or greater of the GNU implementation of tar has transparent support for tarballs compressed with lzma and xz, using the switches -xz or -J for xz compression, and -lzma for LZMA compression. They cannot bundle multiple files into a single archive – to do this an archiving program is used first, such as tar. Just like gzip and bzip, xz and lzma can only compress single files (or data streams) as input. XZ Utils can compress and decompress both the xz and lzma file formats, but since the LZMA format is now legacy, XZ Utils compresses by default to xz.īoth the behavior of the software as well as the properties of the file format have been designed to work similarly to those of the popular Unix compressing tools gzip and bzip2. Various command shortcuts exist, such as lzma (for xz -format=lzma), unxz (for xz -decompress analogous to gunzip) and xzcat (for unxz -stdout analogous to zcat) liblzma, a software library with an API similar to zlib.xz, the command-line compressor and decompressor (analogous to gzip).XZ Utils consists of two major components: Compression can be much slower than gzip, and is slower than bzip2 for high levels of compression, and is most useful when a compressed file will be used many times. Decompression speed is higher than bzip2, but lower than gzip. In most cases, xz achieves higher compression rates than alternatives like gzip and bzip2. XZ Utils started as a Unix port of Igor Pavlov's LZMA- SDK that has been adapted to fit seamlessly into Unix environments and their usual structure and behavior. For compression/decompression the Lempel–Ziv–Markov chain algorithm (LZMA) is used. XZ Utils (previously LZMA Utils) is a set of free software command-line lossless data compressors, including the programs lzma and xz, for Unix-like operating systems and, from version 5.0 onwards, Microsoft Windows. (but see details in Development and adoption) If a compression level isn't specified, it defaults to max.Public domain. The following table summarizes the approximate memory requirements for each of the supported lzma compression levels. However, depending on the compression level used, it can be significantly slower at compressing, and consume a lot more memory. It typically compresses significantly better than the zip and bzip methods. Lzma is the method of compression employed by the 7-Zip LZMA compressor. If a compression level isn't specified, it defaults to 9. Up to 4 MB of memory is required during decompression, and up to 8 MB during compression. It almost always compresses better than zip but is usually slower in both compression and decompression. If a compression level isn't specified, it defaults to 7.īzip is the method of compression employed by the bzip2 compressor. zip, like lzma2, has one special property, though: it will not expand incompressible data (e.g., files that are already compressed). It is fast in both compression and decompression, and has very low memory requirements (less than 1 MB for both compression and decompression at level 9), but generally does not compress nearly as well as the other supported methods. Zip is the method of compression employed by. Higher levels compress better but take longer doing so, and may also require more memory while compressing/decompressing. This specifies the method of compression to use on the files, and optionally the level of compression.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |