Linux XZ压缩格式学习

Posted

tags:

篇首语:本文由小常识网(cha138.com)小编为大家整理,主要介绍了Linux XZ压缩格式学习相关的知识,希望对你有一定的参考价值。

 

XZ的介绍

 

今天升级Python的时候,下载的Python-2.7.8.tar.xz安装包为xz格式,好吧,我又孤陋寡闻了,居然第一次遇见xz格式的压缩文件。搜索了一下资料,下面是xz的一些介绍:

 

xz是一个使用 LZMA压缩算法的无损数据压缩文件格式。和gzip与bzip2一样,同样支持多文件压缩,但是约定不能将多于一个的目标文件压缩进同一个档案文件。相反,xz通常作为一种归档文件自身的压缩格式,例如使用tar或cpioUnix程序创建的归档。xz 在GNU coreutils(版本 7.1 或更新)中被使用。xz 作为压缩软件包被收录在 Fedora (自Fedora 12起), Arch Linux, FreeBSD、 Slackware Linux、CRUX 和 Funtoo中。

 

XZ Utils压缩代码的核心是基于LZMA SDK,但它已经被修改了很多以适应XZ Utils。主压缩算法目前是LZMA2,它在.xz容器格式中使用。 使用典型文件,XZ Utils比gzip创建的输出比gzip小30%,比bzip2小15%。到目前为止,lzma utils 的压缩率仍是最大的,XZ Utils 解压时间占优势。

 

XZ Utils的官方网站为:http://tukaani.org/xz/ ,官网关于XZ的介绍资料如下:

 

XZ Utils

 

XZ Utils is free general-purpose data compression software with a high compression ratio. XZ Utils were written for POSIX-like systems, but also work on some not-so-POSIX systems. XZ Utils are the successor to LZMA Utils.

The core of the XZ Utils compression code is based on LZMA SDK, but it has been modified quite a lot to be suitable for XZ Utils. The primary compression algorithm is currently LZMA2, which is used inside the .xz container format. With typical files, XZ Utils create 30 % smaller output than gzip and 15 % smaller output than bzip2.

XZ Utils consist of several components:

·         liblzma is a compression library with an API similar to that of zlib.

·         xz is a command line tool with syntax similar to that of gzip.

·         xzdec is a decompression-only tool smaller than the full-featured xz tool.

·         A set of shell scripts (xzgrep, xzdiff, etc.) have been adapted from gzip to ease viewing, grepping, and comparing compressed files.

·         Emulation of command line tools of LZMA Utils eases transition from LZMA Utils to XZ Utils.

While liblzma has a zlib-like API, liblzma doesn\'t include any file I/O functions. A separate I/O library is planned, which would abstract handling of .gz, .bz2, and .xz files with an easy to use API.

 

 

XZ的安装

 

从官方网址下载https://tukaani.org/xz/xz-5.2.3.tar.gz后,安装非常简单。如果你可以yum安装,那么就更简单。有些版本甚至默认就自带xz压缩命令。

 

tar -xzvf xz-5.2.3.tar.gz

cd xz-5.2.3

./configure

make

make install

 

XZ的使用

 

 

-z

force compression

压缩文件

-d

force decompression

解压文件

-t

test compressed file integrity

测试压缩文件完整性

-l

list information about .xz files

列出压缩文件.xz的一些信息

-k

keep (don\'t delete) input files

保留被解压缩的文件

-f

force overwrite of output file and (de)compress links

强制覆盖输出文件和(de)压缩链接

-c

write to standard output and don\'t delete input files

压缩输入标准输出并保留被压缩的文件。

-0 … -9

compression preset; default is 6; take compressor *and*                    decompressor memory usage into account before using 7-9!

压缩率预设参数 -0 -9调节压缩率。如果不设置,默认压缩等级是6

-e

try to improve compression ratio by using more CPU time;                      does not affect decompressor memory requirements

尝试通过使用更多的CPU时间来提高压缩比; 不影响解压内存的要求

-T

use at most NUM threads; the default is 1; set to 0 to use as many threads as there are processor cores

压缩的线程数量。默认为1,设置为0表示跟处理器核数匹配

-q

suppress warnings; specify twice to suppress errors too

抑制警告 指定两次以抑制错误

-v

be verbose; specify twice for even more verbose

显示压缩、解压详细信息

-H

display the long help (lists also the advanced options)

显示更多的帮助信息,包含告警选项。

-V

以上是关于Linux XZ压缩格式学习的主要内容,如果未能解决你的问题,请参考以下文章

Linux下xz与tar的区别

黑猴子的家:tar xz是啥压缩格式,和tar gz比起来哪个好用??

.xz文件解压及linux常见压缩

Linux压缩格式

压缩打包介绍,gzipbzip2xz压缩工具

常见压缩格式比对,及 Linux 下的压缩相关指令

(c)2006-2024 SYSTEM All Rights Reserved IT常识