18. 打包压缩

6.1 压缩打包介绍

6.2 gzip压缩工具

gzip, gunzip, zcat - compress or expand files

# gzip 1.txt

# ls

1.txt.gz

# gzip -f test/

gzip: test/ is a directory -- ignored

-d --decompress --uncompress

Decompress.

# gzip -d 1.txt.gz

-# --fast --best

Regulate the speed of compression using the specified digit #,

where -1 or --fast indicates the fastest

compression method (less compression) and -9 or --best

indicates the slowest compression method (best compression).

The default compression level is -6 (that is, biased towards high compression at expense of speed).

# gzip -9 1.txt

-c --stdout --to-stdout

Write output on standard output; keep original files unchanged.

# gzip -c 1.txt > 1.txt.gz

# ls

1.txt 1.txt.gz

# gzip -cd 1.txt.gz > 2.txt

# ls

1.txt 1.txt.gz 2.txt

# gunzip -c 1.txt.gz > 3.txt

# ls

1.txt 1.txt.gz 2.txt 3.txt

Compressed files can be restored to their original form using gzip -d or gunzip or zcat.

If the original name saved in the compressed file is not suitable for its file system, a new name is constructed from the original one to make it legal.

# gunzip 1.txt.gz

# gzip -9 1.txt

# file 1.txt.gz

1.txt.gz: gzip compressed data, was "1.txt", from Unix, last modified: Sat Jan 6 09:32:23 2018, max compression

# gzip 1.txt

# file 1.txt.gz

1.txt.gz: gzip compressed data, was "1.txt", from Unix, last modified: Sat Jan 6 09:32:23 2018

# gzip -1 1.txt

# file 1.txt.gz

1.txt.gz: gzip compressed data, was "1.txt", from Unix, last modified: Sat Jan 6 09:32:23 2018, max speed

# gzip -3 1.txt

# file 1.txt.gz

1.txt.gz: gzip compressed data, was "1.txt", from Unix, last modified: Sat Jan 6 09:32:23 2018

zcat is identical to gunzip -c.

# zcat 1.txt.gz

6.3 bzip2压缩工具

bzip2 compresses files using the Burrows-Wheeler block sorting text compression algorithm, and Huffman coding.

# yum -y install bzip2

# bzip2 -f test/

bzip2: Input file test/ is a directory.

# bzip2 1.txt

# ls

1.txt.bz2

# file 1.txt.bz2

1.txt.bz2: bzip2 compressed data, block size = 900k

-c --stdout

Compress or decompress to standard output.

# bzip2 -c 1.txt > 1.txt.bz2

# ls

1.txt 1.txt.bz2

# bzip2 -cd 1.txt.bz2 > 2.txt

# ls

1.txt 1.txt.bz2 2.txt

-d --decompress

Force decompression. bzip2, bunzip2 and bzcat are really the same program

# bzip2 -d 1.txt.bz2

# ls

1.txt

-1 (or --fast) to -9 (or --best)

Set the block size to 100 k, 200 k .. 900 k when compressing.

The default compression level is -9.

Has no effect when decompressing.

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.

# bzip2 -9 2.txt

# file 2.txt.bz2

2.txt.bz2: bzip2 compressed data, block size = 900k

# bzip2 -1 1.txt

# file 1.txt.bz2

1.txt.bz2: bzip2 compressed data, block size = 100k

# bzip2 1.txt

# file 1.txt.bz2

1.txt.bz2: bzip2 compressed data, block size = 900k

-z --compress

The complement to -d: forces compression, regardless of the invocation name.

# bunzip2 -z 1.txt

# ls

1.txt.bz2 2.txt test

bzcat - decompresses files to stdout

6.4 xz压缩工具

xz, unxz, xzcat, lzma, unlzma, lzcat - Compress or decompress .xz and .lzma files

unxz is equivalent to xz --decompress.

xzcat is equivalent to xz --decompress --stdout.

# xz -f test/

xz: test/: Is a directory, skipping

# xz 1.txt

# ls

1.txt.xz

-z, --compress

Compress.

This is the default operation mode when no operation mode option is specified

# unxz -z 1.txt

[root@aminglinux-01 d6z]# ls

1.txt.xz

-d, --decompress, --uncompress

Decompress.

# xz -d 1.txt.xz

# ls

1.txt

-k, --keep

Don't delete the input files.

-c, --stdout, --to-stdout

Write the compressed or decompressed data to standard output instead of a file.

This implies --keep.

# xz -c 1.txt > 1.txt.xz

# ls

1.txt 1.txt.xz

# xz -cd 1.txt.xz > 3.txt

# ls

1.txt 1.txt.xz 2.txt 3.txt

-0 ... -9

Select a compression preset level.

The default is -6.

If multiple preset levels are specified, the last one takes effect.

6.5 zip压缩工具

yum -y install zip

zip - package and compress (archive) files

zip is a compression and file packaging utility for Unix, VMS, MSDOS, OS/2, Windows 9x/NT/XP, Minix, Atari, Macintosh, Amiga, and Acorn RISC OS.

It is analogous to a combination of the Unix commands tar(1) and compress(1) and is compatible with PKZIP (Phil Katz's ZIP for MSDOS systems).

# ls

1.txt

# zip 1.txt.zip 1.txt

adding: 1.txt (deflated 75%)

# ls

1.txt 1.txt.zip

-r

--recurse-paths

Travel the directory structure recursively

# zip test.zip test/ 1.txt 1.txt.zip

adding: test/ (stored 0%)

adding: 1.txt (deflated 75%)

adding: 1.txt.zip (stored 0%)

# zip -r test.zip test/ 1.txt 1.txt.zip

adding: test/ (stored 0%)

adding: test/123/ (stored 0%)

adding: 1.txt (deflated 75%)

adding: 1.txt.zip (stored 0%)

yum -y install unzip

unzip - list, test and extract compressed files in a ZIP archive

# unzip test.zip

Archive: test.zip

replace 1.txt? [y]es, [n]o, [A]ll, [N]one, [r]ename:

[-d exdir]

An optional directory to which to extract files.

By default, all files and subdirectories are recreated in the current directory;

# unzip test.zip -d 456/

Archive: test.zip

creating: 456/test/

creating: 456/test/123/

inflating: 456/1.txt

extracting: 456/1.txt.zip

-l list archive files (short format).

# unzip -l test.zip

Archive: test.zip

Length Date Time Name

--------- ---------- ----- ----

0 01-07-2018 02:12 test/

0 01-07-2018 02:12 test/123/

2156850 01-06-2018 10:59 1.txt

541324 01-07-2018 02:05 1.txt.zip

--------- -------

2698174 4 files

6.6 tar打包

GNU `tar' saves many files together into a single tape or disk archive, and can restore individual files from the archive.

tar打包或解包时，会直接覆盖已有文件或目录，没有任何提示。

SYNOPSIS

tar [OPTION...] [FILE]...

EXAMPLES

tar -cf archive.tar foo bar

# Create archive.tar from files foo and bar.

tar -tvf archive.tar

# List all files in archive.tar verbosely.

# tar -tf xxx.tar

2.txt

1.txt

456/

# tar -tvf xxx.tar

-rw-r--r-- root/root 4 2018-01-08 10:47 2.txt

-rw-r--r-- root/root 2156850 2018-01-06 10:59 1.txt

drwxr-xr-x root/root 0 2018-01-07 02:24 456/

tar -xf archive.tar

# Extract all files from archive.tar.

Main operation mode:

-A, --catenate, --concatenate

append tar files to an archive

-c, --create

create a new archive

-d, --diff, --compare

find differences between archive and file system

--delete

delete from the archive (not on mag tapes!)

-r, --append

append files to the end of an archive

-t, --list

list the contents of an archive

-u, --update

only append files newer than copy in archive

-x, --extract, --get

extract files from an archive

Common options:

-C, --directory=DIR

change to directory DIR

-v, --verbose

verbosely list files processed

-f, --file=ARCHIVE

use archive file or device ARCHIVE

Local file selection:

--exclude=PATTERN

exclude files, given as a PATTERN

# tar -cvf xxx.tar --exclude 1.txt --exclude 2.txt 1.txt 2.txt test.zip

# tar -cvf xxx.tar --exclude "*.txt" 1.txt 2.txt test.zip

6.7 打包并压缩

-j, --bzip2

filter the archive through bzip2

-J, --xz

filter the archive through xz

-z, --gzip

filter the archive through gzip

tar -zcvf 123.tar.gz 123

tar -zxvf 123.tar.gz

tar -jcvf 123.bz2 123

tar -jxvf 123.bz2

tar -Jcvf 123.xz 123

tar -Jxvf 123.xz

tar -tf 123.bz2 / tar -tf 123.gz / tar -tf 123.xz