Linux compression and decompression

. Tar
Unpack: Tar xvf filename.tar
Package: Tar CVF filename.tar dirname
(Note: tar is packed, not compressed !)
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. GZ
Decompress 1: gunzip filename.gz
Decompress 2: gzip-D filename.gz
Compression: gzip filename
.Tar.gz and. tgz
Decompress: Tar zxvf filename.tar.gz
Compression: Tar zcvf filename.tar.gz dirname
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. Bz2
Decompress 1: Bzip2-D filename.bz2
Decompress 2: bunzip2 filename.bz2
Compression: Bzip2-Z filename
.Tar.bz2
Decompress: Tar jxvf filename.tar.bz2
Compression: Tar jcvf filename.tar.bz2 dirname
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. Bz
Extract 1: Bzip2-D filename. bz
Decompress 2: bunzip2 filename. bz
Compression: Unknown
. Tar. bz
Decompress: Tar jxvf filename.tar. bz
Compression: Unknown
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. Z
Decompress: uncompress filename. Z
Compression: compress filename
. Tar. Z
Decompress: Tar zxvf filename.tar. Z
Compression: Tar zcvf filename.tar. Z dirname
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. Zip
Decompress: unzip filename.zip
Compression: Zip filename.zip dirname
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. Rar
Decompress: rar a filename.rar
Compression: R ar e filename.rar
RAR please go to: http://www.rarsoft.com/download.htm
After decompression, copy rar_static to the/usr/bin directory (Other Directories specified by the $ PATH environment variable can also be used ):
[Root @ www2 TMP] # cp rar_static/usr/bin/RAR
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. LHA
Decompress: LHA-e filename. LHA
Compression: LHA-a filename. LHA filename
Lha please: http://www.infor.kanazawa-it.ac.jp /~ Ishii/lhaunix/

> After decompression, copy LHA to the/usr/bin directory (Other Directories specified by the $ PATH environment variable can also be used ):
[Root @ www2 TMP] # cp LHA/usr/bin/
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. Rpm
Unpack: rpm2cpio filename. RPM | cpio-Div
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. Deb
Unpack: Ar P filename. Deb data.tar.gz | tar zxf-
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Detailed command usage:

Tar command

[Root @ Linux ~] #Tar [-cxtzjvfppn] file and directory .... Parameters: -C: Create a parameter command for the compressed file ); -X: Unlock the parameter command of a compressed file! -T: view the files in the tarfile! Note that C/X/T can only exist under the parameter! Cannot exist at the same time! Because it is impossible to simultaneously compress and decompress. -Z: does it have the gzip attribute at the same time? That is, do I need to use gzip for compression? -J: Does it have Bzip2 attributes at the same time? That is, do I need to use Bzip2 for compression? -V: The file is displayed during compression! This is common, but it is not recommended to use it in the background execution process! -F: use the file name. Please note that the file name should be followed immediately after F! Do not add parameters! For example, using "Tar-zcvfp tfile sfile" is an incorrect method. "Tar-zcvpf tfile sfile" is correct! -P: use the original attributes of the original file (the attributes will not be changed based on the user) -P: absolute paths can be used for compression! -N: a new date (yyyy/mm/DD) will be packed into the new file! -- Exclude file: do not pack the file during compression! Example: Example 1: package all the files in the/etc directory into/tmp/etc.tar [Root @ Linux ~] #Tar-CVF/tmp/etc.tar/etc<= Package only, not compressed! [Root @ Linux ~] #Tar-zcvf/tmp/etc.tar.gz/etc<= Compressed with gzip After packaging [Root @ Linux ~] #Tar-jcvf/tmp/etc.tar.bz2/etc<= Compressed with Bzip2 After packaging # Note that the file name after parameter F is obtained by ourselves. We use. tar for identification. # If the Z parameter is added, .tar.gz or. tgz is used to represent the tar file ~ compressed by gzip ~ # If you add the J parameter, use .tar.bz2 as the file name ~ # A warning message is displayed when the preceding command is executed: # "Tar: removing leading '/' from Member names" is a special setting for absolute paths. Example 2: Check the files in the above/tmp/etc.tar.gz file? [Root @ Linux ~] #Tar-ztvf/tmp/etc.tar.gz # When we use gzip to compress the files in the TAR file, # Add the Z parameter! This is important! Example 3: Decompress the/tmp/etc.tar.gz file under/usr/local/src. [Root @ Linux ~] #CD/usr/local/src [Root @ Linux SRC] #Tar-zxvf/tmp/etc.tar.gz # By default, We Can uncompress files anywhere! In this example, # First, I will transform the working directory to the/usr/local/src directory, and unlock/tmp/etc.tar.gz, # The unlocked directory will be in/usr/local/src/etc! In addition, if you enter/usr/local/src/etc # The file attributes in this directory may be different from those in/etc! Example 4: Under/tmp, I only want to unbind the etc/passwd in/tmp/etc.tar.gz. [Root @ Linux ~] #CD/tmp [Root @ Linux TMP] #Tar-zxvf/tmp/etc.tar.gz etc/passwd # I can use tar-ztvf to check the file name in the tarfile. If you only need one file, # You can issue it in this way! Notice! The root directory in etc.tar.gz/is removed! Example 5: Back up all the files in/etc/and save their permissions! [Root @ Linux ~] #Tar-zxvpf/tmp/etc.tar.gz/etc # This-P attribute is very important, especially when you want to keep the attributes of the original file! Example 6: only new files in/home are backed up. [Root @ Linux ~] #Tar-N '2014/1/01'-zcvf home.tar.gz/home Example 7: I want to back up/home,/etc, but not/home/dmtsai [Root @ Linux ~] #Tar -- exclude/home/dmtsai-zcvf myfile.tar.gz/home/*/etc Example 8: package/etc/and unpack it under/tmp without generating a file! [Root @ Linux ~] #CD/tmp [Root @ Linux TMP] #Tar-CVF-/etc | tar-xvf- # This action is a bit like CP-r/etc/tmp ~ It is still useful! # Note that the output file is changed to-and the input file is changed to-, and there is another file | Yes ~ # This represents standard output, standard input, and pipeline commands respectively! # This part will be explained again when we mention this command in bash shell!

Gzip and zcat commands

[Root @ Linux ~] # Gzip [-CDT #] File Name [Root @ Linux ~] # Zcat file name .gz Parameters: -C: outputs compressed data to the screen and can be processed through data stream redirection; -D: extract parameters; -T: it can be used to check the consistency of a compressed file ~ Check whether the file has any errors; -#: Compression level.-1 is the fastest, but the compression ratio is the worst.-9 is the slowest, but the compression ratio is the best! Default Value:-6 ~ Example: Example 1: Convert/etc/man. config to/tmp and compress it with Gzip [Root @ Linux ~] # Cd/tmp [Root @ Linux TMP] # cp/etc/man. config. [Root @ Linux TMP] # gzip man. config # At this time, man. config will become man.config.gz! Example 2: Read the content of Example 1! [Root @ Linux TMP] # zcat man.config.gz # The man.config.gz extracted file content is displayed on the screen !! Example 3: Decompress the file in Example 1 [Root @ Linux TMP] # gzip-D man.config.gz Example 4: compress man. config unlocked in Example 3 with the optimal compression ratio and keep the original file [Root @ Linux TMP] # gzip-9-C man. config> man.config.gz

Bzip2, bzcat command

[Root @ Linux ~] # Bzip2 [-CDZ] File Name [Root @ Linux ~] # Bzcat file name .bz2 Parameters: -C: output the data generated during the compression process to the screen! -D: extracted Parameters -Z: Compression Parameters -#: Same as gzip, it is used to calculate the compression ratio.-9 is the best, and-1 is the fastest! Example: Example 1: compress/tmp/man. config with Bzip2 [Root @ Linux TMP] # Bzip2-Z Man. config # At this time, man. config will become man.config.bz2! Example 2: Read the content of Example 1! [Root @ Linux TMP] # bzcat man.config.bz2 # The man.config.bz2 extracted file content is displayed on the screen !! Example 3: Decompress the file in Example 1 [Root @ Linux TMP] # Bzip2-D man.config.bz2 Example 4: compress man. config unlocked in Example 3 with the optimal compression ratio and keep the original file [Root @ Linux TMP] # Bzip2-9-C man. config> man.config.bz2

Compress command

[Root @ Linux ~] # Compress [-DCR] file or directory Parameters: -D: extract parameters. -R: It can be compressed together with files in the directory! -C: Output compressed data to standard output (output to the screen) Example: Example 1: Convert/etc/man. config to/tmp and compress it [Root @ Linux ~] # Cd/tmp [Root @ Linux TMP] # cp/etc/man. config. [Root @ Linux TMP] # compress man. config [Root @ Linux TMP] # ls-l -RW-r -- 1 Root 2605 Jul 27 :43 man. config. Z Example 2: Unlock the compressed file [Root @ Linux TMP] # compress-d man. config. Z Example 3: compress man. config into another file for backup [Root @ Linux TMP] # compress-C man. config> man. config. Back. Z [Root @ Linux TMP] # ll man. config * -RW-r -- 1 Root 4506 Jul 27 :43 man. config -RW-r -- 1 Root 2605 Jul 27 :46 man. config. Back. Z # This-C parameter is interesting! He will output the data from the compression process to the screen, instead of writing the data # File. Z file. Therefore, we can output data to another file name through data stream redirection. # Concerning data stream redirection, we will discuss it in detail in bash shell!

Dd command

[Root @ Linux ~] # Dd If = "input_file" of = "outptu_file" BS = "block_size "\ Count = "Number" Parameters: If: input file ~ It can also be a device! Of: output file ~ It can also be a device; BS: the size of a planned block. If no value is set, the default value is 512 bytes. Count: the number of BS. Example: Example 1: Back up/etc/passwd to/tmp/passwd. Back [Root @ Linux ~] # Dd If =/etc/passwd of =/tmp/passwd. Back 3 + 1 records in 3 + 1 records out [Root @ Linux ~] # Ll/etc/passwd/tmp/passwd. Back -RW-r -- 1 Root 1746 Aug 25 14:16/etc/passwd -RW-r -- 1 Root 1746 Aug 29 16:57/tmp/passwd. Back # Take a closer look. The size of my/etc/passwd file is 1746 bytes, because I have not set BS, # Therefore, the default value is 512 bytes. Therefore, the above 3 + 1 indicates three complete #512 bytes, and another block under 512 bytes! # In fact, it seems like the CP command ~ Example 2: backup/dev/hda MBR [Root @ Linux ~] # Dd If =/dev/hda of =/tmp/MBR. Back BS = 512 COUNT = 1 1 + 0 records in 1 + 0 records out # You have to understand this ~ We know that the MBR of the entire hard disk is 512 bytes, # It is the first sector on the hard disk. Therefore, I can use this method # Record all the data in the MBR. It's really amazing! Pai_^ Example 3: Back up the entire/dev/hda1 partition. [Root @ Linux ~] # Dd If =/dev/hda1 of =/Some/path/filenaem # This command is amazing! Back up all the content of the entire partition ~ # The following of must not be in the/dev/hda1 directory ~ Otherwise, you cannot finish reading ~ # This action is very useful. If you need to complete the content of the entire partition in the next day, # You can use dd If =/Some/file of =/dev/hda1 to write data to the hard disk. # If you want to back up the entire hard disk, it is similar to Norton's ghost software, # From disk to disk, hey ~ You can use dd ~ Amazing!

Cpio command

[Root @ Linux ~] # Cpio-covb> <= backup [Root @ Linux ~] # Cpio-icduv <= restore Parameters: -O: copy the data to a file or device. -I: copy the data from a file or device to the system. -T: view the files or device content created by cpio -C: A new portable format Storage Method -V: enables the file name to be displayed on the screen during storage. -B: Increase the preset blocks size to 5120 bytes. The default value is 512 bytes! This improves the storage speed of large files (refer to the I-nodes concept) -D: automatically create a directory! The contents of cpio may not be in the same directory, In this case, there will be problems in the anti-backup process! If-D is added at this time, You can automatically create the required directory! -U: automatically overwrites older files! Example: Example 1: Write all information on the system to the tape drive! [Root @ Linux ~] # Find/-print | cpio-covb>/dev/st0 # Generally, the serial number of the tape drive using the SCSI interface is/dev/st0! Example 2: Check what files exist on the tape drive? [Root @ Linux ~] # Cpio-icdeep </dev/st0 [Root @ Linux ~] # Cpio-icvt </dev/st0>/tmp/Content # In the first action, the files in the drive will be listed on the screen, and we can use the second action, # Record all file names to the/tmp/content file! Example 3: Restore the information on the tape ~ [Root @ Linux ~] # Cpio-icduv </dev/st0 # Generally, the serial number of the tape drive using the SCSI interface is/dev/st0! Example 4: Back up all the "Files" under/etc to/root/etc. cpio! [Root @ Linux ~] # Find/etc-type F | cpio-o>/root/etc. cpio # Back up data ~ You can also use cpio-I </root/etc. cpio # Capture the information !!!!

Reference: http://www.chinaitlab.com/www/techspecial/tar/