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Editor to share with you the Shell command file compression and decompression of gzip, zip case study, I believe that most people do not know much about it, so share this article for your reference, I hope you can learn a lot after reading this article, let's go to know it!

1.gzip:gzip Compression tool

The functional description of the gzip command:

The gzip command is used to compress files. Gzip is a widely used compression program that compresses files with the .gz extension after their names.

The syntax format of the gzip command:

Gzip [- acdfhlLnNrtvV19] [- S suffix] [name.] gzip [- acdfhlLnNqrtvV] [- S] [-] [--best/fast] [file.] Or gzip [- acdfhlLnNqrtvV] [- S] [-] [--best/fast] [directory]

Common parameters of the gzip command are described as follows:

There are many parameters for gzip. The following are the parameters and description of the gzip command:

Explanation of parameter options

-an or-- ascii uses ASCII text mode.

-c or-- stdout or-- to-stdout outputs the compressed file to a standard output device without changing the original file.

-d or-- decompress or-uncompress unpack the compressed file.

-f or-- force forcibly compress the file. Regardless of whether the file name or hard connection exists and whether the file is a symbolic link.

-h or-- help online help.

-l or-- list lists information about the compressed file.

-L or-- license displays version and copyright information.

When-n or-- no-name compresses a file, the original file name and timestamp are not saved.

When-N or-- name compresses the file, saves the original file name and timestamp.

-Q or-- quiet does not display a warning message.

-r or-- recursive recursive processing, processing all files and subdirectories under the specified directory together.

-S or-suffix changes the compressed suffix string.

-t or-- test tests whether the compressed file is correct.

-v or-- verbose shows the instruction execution process.

-V or-- version displays version information.

-Compression efficiency is a value between 1Mui 9 and the default value is "6". The higher the specified value, the higher the compression efficiency.

-- best this parameter has the same effect as specifying the "- 9" parameter.

-- fast this parameter has the same effect as specifying the "- 1" parameter.

Practical operation of gzip command

Example 1: compressed file

[root@m01 ~] # ls displays the current directory file a.c b.h d.cpp [root@m01 ~] # gzip * all files in the compressed directory [root@w3cschool.cc a] # [root@m01 ~] # ls shows the current directory file a.c.gz b.h.gz d.cpp.gz

Example 2: follow example 1 and list the detailed information

[root@m01] # gzip-dv * extract the file and list the details a.c.gz: 0. 0%-- replaced with a.cb.h.gz: 0. 0%-- replaced with b.hd.cpp.gz: 0. 0%-- replaced with d.cpp

Example 3: follow example 1 to display the information of the compressed file

[root@m01] # gzip-l * compressed uncompressed ratio uncompressed_name 24 0 0 0% a.c 24 0 0 0% b.h 26 0 0 0% d.cpp

2. Zip: compression tool

Functional description of the zip command

The zip command is used to compress files. Zip is a widely used compression program that compresses files to produce additional compressed files with the .zip extension.

Syntax format of the zip command

Zip [- aABcdDeEfFghjklLmoqrRSTuvVwXyzcompressed $] [--longoption...] [- b path] [- n suffixes] [- t date] [- tt date] zip [- AcdDfFghjJKlLmoqrSTuvVwXyz$] [- b] [- ll] [- n] [- t] [-] [compressed file] [file.] [- I] [- x]

Common parameters of the zip command are described as follows:

There are many parameters for zip. The following are the parameters and description of the zip command:

Explanation of parameter options

-An adjusts the executable automatic unzipping file.

-b specifies the directory where the files are temporarily stored.

-c comment each compressed file.

-d removes the specified file from the compressed file.

-D the directory name is not established in the compressed file.

-f the effect of this parameter is similar to that of specifying the "- u" parameter, but not only updates the existing file, but also adds some files to the compressed file if they do not already exist in the compressed file.

-F attempts to repair a corrupted compressed file.

-g append a compressed file to an existing compressed file instead of creating a new one.

-h online help.

-I only compress files that meet the criteria.

-j saves only the file name and its contents, but does not store any directory names.

-J deletes unnecessary data in front of the compressed file.

-k uses file names in MS-DOS-compatible format.

When compressing a file, replace LF characters with LF+CR characters.

-ll replaces LF+CR characters with LF characters when compressing the file.

-L displays copyright information.

-m after compressing the file and adding the compressed file, delete the original file, that is, move the file to the compressed file.

-n does not compress files with specific suffix strings.

-o set the change time of the compressed file to the same as the file with the latest change time in the compressed file.

-Q does not show the instruction execution process.

-r Recursive processing, processing all files and subdirectories under the specified directory together.

-S contains system and hidden files.

-t sets the date of the compressed file to the specified date.

-T check that each file in the backup file is correct.

-u replace the newer file into the compressed file.

-v displays instruction execution or version information.

-V saves the file properties of the VMS operating system.

-w if the version number is in the file name, this parameter is valid only under the VMS operating system.

-x excludes eligible files when compressing.

-X does not save additional file properties.

-y saves the symbolic link directly, not the file that the connection points to. This parameter is valid only in systems such as UNIX.

-z comment the compressed file.

-$saves the volume name of the disk where the first compressed file is located.

-Compression efficiency is a value between 1 and 9.

Practical operation of zip command

Example 1: package all files and folders in the / home/html/ directory to the html.zip in the current directory:

Zip-Q-r html.zip / home/html

Example 2: if we are in the / home/html directory, we can execute the following command:

Zip-Q-r html.zip *

Example 3: delete the file a.c from the compressed file cp.zip

Zip-dv cp.zip a.c

The above are all the contents of the Shell command file compression and decompression of gzip, zip case studies, thank you for reading! I believe we all have a certain understanding, hope to share the content to help you, if you want to learn more knowledge, welcome to follow the industry information channel!

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