加入收藏 | 设为首页 | 会员中心 | 我要投稿 济南站长网 (https://www.0531zz.com/)- 科技、建站、经验、云计算、5G、大数据,站长网!
当前位置: 首页 > 服务器 > 搭建环境 > Linux > 正文

Linux / Unix Command: bunzip2--reference

发布时间:2021-01-24 11:05:43 所属栏目:Linux 来源:网络整理
导读:副标题#e# http://linux.about.com/library/cmd/blcmdl1_bunzip2.htm NAME bzip2,bunzip2 - a block-sorting file compressor,v1.0.2?bzcat - decompresses files to stdout?bzip2recover - recovers data from damaged bzip2 files ? SYNOPSIS bzip2?[?-cd

?

OPTIONS

-c --stdout
Compress or decompress to standard output.
-d --decompress
Force decompression.?bzip2,?bunzip2?and?bzcat?are really the same program,and the decision about what actions to take is done on the basis of which name is used. This flag overrides that mechanism,and forces?bzip2?to decompress.
-z --compress
The complement to -d: forces compression,regardless of the invocation name.
-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.
-f --force
Force overwrite of output files. Normally,?bzip2?will not overwrite existing output files. Also forces?bzip2?to break hard links to files,which it otherwise wouldn't do.

bzip2 normally declines to decompress files which don't have the correct magic header bytes. If forced (-f),however,it will pass such files through unmodified. This is how GNU gzip behaves.

-k --keep
Keep (don't delete) input files during compression or decompression.
-s --small
Reduce memory usage,for compression,decompression and testing. Files are decompressed and tested using a modified algorithm which only requires 2.5 bytes per block byte. This means any file can be decompressed in 2300k of memory,albeit at about half the normal speed.

During compression,-s selects a block size of 200k,which limits memory use to around the same figure,at the expense of your compression ratio. In short,if your machine is low on memory (8 megabytes or less),use -s for everything. See MEMORY MANAGEMENT below.

-q --quiet
Suppress non-essential warning messages. Messages pertaining to I/O errors and other critical events will not be suppressed.
-v --verbose
Verbose mode -- show the compression ratio for each file processed. Further -v's increase the verbosity level,spewing out lots of information which is primarily of interest for diagnostic purposes.
-L --license -V --version
Display the software version,license terms and conditions.
-1 (or --fast) to -9 (or --best)
Set the block size to 100 k,200 k .. 900 k when compressing. Has no effect when decompressing. See MEMORY MANAGEMENT below. The --fast and --best aliases are primarily for GNU gzip compatibility. In particular,--fast doesn't make things significantly faster. And --best merely selects the default behaviour.
--
Treats all subsequent arguments as file names,even if they start with a dash. This is so you can handle files with names beginning with a dash,for example: bzip2 -- -myfilename.
--repetitive-fast --repetitive-best
These flags are redundant in versions 0.9.5 and above. They provided some coarse control over the behaviour of the sorting algorithm in earlier versions,which was sometimes useful. 0.9.5 and above have an improved algorithm which renders these flags irrelevant.

(编辑:济南站长网)

【声明】本站内容均来自网络,其相关言论仅代表作者个人观点,不代表本站立场。若无意侵犯到您的权利,请及时与联系站长删除相关内容!

热点阅读