Linux compression and archiving

Basic concepts:

Compression: The file according to some algorithm to reduce, such as a text file content is: AAAAADDDD We can simplify it as a5d4 need to restore back, so that the original text storage needs 18 Bytes, now only need 8 bytes, greatly save space, generally speaking, the simpler the compression algorithm, The faster the compression speed, the more complex the algorithm, the higher the compression ratio [(the size before compression-the size after compression)/the size before compression).

Archive (archive): Compression can only compress the file, but not the directory, and archiving is the collection of multiple files together to form a file, so that we can put the directory, and the contents of the directory is archived together to form a file, and then we can use the tool to compress it. (Note: The archive itself is not compressed)

Compression command:

Compress:filenme.z

Uncompress

Gzip:.gz

Gzip/path/to/somefile Delete source files after compression is complete

-D: Unzip

-#: Specify the compression level, [1-9] 1 The fastest compression ratio is lowest, 9 the slowest compression ratio is the highest, the default is 6

zcat/path/to/somefile.gz View Text File contents

BZIP2:. bz2

Compression tool with a greater compression ratio than gzip

Bzip2/path/to/somefile

-D:

-#：

-K: Keep the original file when compressing

bunzip2/path/to/somefile.bz2

Bzcat

XZ:. XZ

Xz/path/to/somefile

-D

-#:

-K: Compressed retention source file

Unxz

Xzcat

Xzdec

Zip: A compressed and archived tool

Zip filename.zip FILE1 FILE2 ... : The original file is not deleted after compression

Unzip Filename.zip

Tar: Archive tool

-C: Create an archive file

-F File.tar: Archived files for operations

-X: Expand Archive

--xattrs: Preserves extended attribute information for files when archiving

-T: Do not expand the archive to directly see which files are archived

-ZCF: Archive and invoke gzip compression

-ZXF: Call gzip to unzip and expand Archive,-Z option to omit

-jcf:bzip2

-JXF:

-jcf:xz

-JXF:

Exercise: Write a script

From the keyboard allows the user to enter several files, the script can archive this several files into a file

Read

-P "PROMPT": Give a hint

This article from "Single Season rice" blog, declined reprint!

Linux compression and archiving