Linux tar command details

Tar command
Tar can create files and directories. Using tar, you can create a file (backup file) for a specific file, change the file in the file, or add a new file to the file. Tar
Files are originally used to create files on tapes. Now, you can create files, such as floppy disks, on any device. The tar command can be used to package a large number of files and directories into one file.
It is very useful to combine several files into one file for network transmission. Tar on Linux is of the GNU version.
Syntax: Tar [primary option + secondary option] file or directory
When you use this command, the main option is required, and it tells tar what to do. The auxiliary option is used for assistance and can be used.
Main options:
C. Create a new archive file. Select this option if you want to back up a directory or some files.
R: append the file to the end of the file. For example, if you have prepared a backup file and find that there is still a directory or some files have forgotten to be backed up, you can use this option to append the directory or files you have forgotten to the backup file.
T list the file content and check which files have been backed up.
U updates the file. That is to say, replace the original backup file with the new file. If the file to be updated cannot be found in the backup file, append it to the end of the backup file.
X release a file from the file.
Auxiliary options:
B. This option is set for the tape drive. It is followed by a number to describe the block size. The default value is 20 (20*512 bytes ).
F. This option is usually required when you use an archive file or device.
K. Save the existing files. For example, if we restore a file, the same file will not be overwritten during restoration.
M sets the modification time of all files to the present when restoring files.
M creates a multi-volume archive file to store it on several disks.
V detailed report on the file information processed by tar. If this option is not available, tar does not report file information.
W each step requires confirmation.
Z uses gzip to compress/decompress the file. With this option, the file can be compressed. However, you must use this option to decompress the file during restoration.

 

Analysis of compressed files in Linux

For those who are new to Linux, they will surely get dizzy with a bunch of various file names in Linux. Let alone, for example, compressing a file. We know that in windows
There are only two common types of compressed files: Zip and. Rap. It can be different from linux.there are .gz).tar.gz?tgz=bz2}.z}.tar and so on.
Many compressed file names can also be used under .zipand .rarin windows. There are too few people using .zipand .rar in linux. This article is coming
Make a summary of these common compressed files. I hope you will not be confused when you encounter these files again :)

Before summarizing various types of compressed files
Clarify two concepts: Packaging and compression. Packaging refers to converting a large number of files or directories into a total file. Compression refers to converting a large file into a small file through some compression algorithms. Why distinguish this?
What are the two concepts? In fact, this is because many Linux compression programs can only compress one file, so when you want to compress a large number of files, you must first use another tool to compress these files first
Into a package, and then compress the original compression program.
At the end of lifecycle. After the tar package is generated, you can use other programs to compress it. So let's first talk about the basic usage of the tar command:
There are many options for the tar command (which can be viewed using man TAR), but there are several commonly used options. The following is an example:
# Tar-CF all.tar *. jpg
This command is to pack all. jpg files into a package named all.tar. -C indicates that a new package is generated.-F specifies the package file name.
# Tar-RF all.tar *. gif
This command adds all .gif files to the package of all.tar. -R indicates adding files.
# Tar-UF all.tar logo.gif
This command is used to update the logo.gif file in tarbao all.tar.-u indicates that the file is updated.

# Tar-TF all.tar
This command is used to list all files in the all.tar package.-T is used to list objects.
# Tar-XF all.tar
This command is used to extract all the files in the all.tar package.
The above is the most basic usage of tar. To help you compress or decompress files while packing and unpackage, tar provides a special feature. This means that tar can call other compression programs, such as gzip and Bzip2, while packaging or unpacking.
1) tar calls Gzip
Gzipis a program developed by gnuorganization. The file ending with .gz is the result of gzip compression. The decompress program relative to gzip is gunzip. Use the-Z parameter in tar to call gzip. The following is an example:
# Tar-CZF all.tar.gz *. jpg
Bytes
# Tar-xzf all.tar.gz
This command unlocks the generated package.
2) tar call Bzip2
Bzip2is a more powerful compression program. The file ending with .bz2 is the result of Bzip2 compression. The decompress program relative to Bzip2 is bunzip2. Use the-J parameter in tar to call gzip. The following is an example:
# Tar-CJF all.tar.bz2 *. jpg
Bytes
# Tar-xjf all.tar.bz2
This command unlocks the generated package.
3) tar call Compress

Compress is also a compression program, but it seems that there are not as many people using compress as gzip and Bzip2 .. The file at the end of Z is the end of Bzip2 compression.
Result. The decompress program relative to compress is uncompress. Use the-Z parameter in tar to call gzip. The following is an example:
# Tar-CZF all.tar. z *. jpg
Forbidden. Z
# Tar-xzf all.tar. Z
This command is used to unbind the generated package.
With the above knowledge, you should be able to uncompress a variety of compressed files. The following is a summary of the compressed files in the TAR series:
1st pair of files ending with .tar
Tar-XF all.tar
2XX for the file ending with .gz
Gzip-D all.gz
Gunzip all.gz
32.16.tgzor .tar.gz
Tar-xzf all.tar.gz
Tar-xzf all. tgz
4)for the file ending with .bz2
Bzip2-D all.bz2
Bunzip2 all.bz2
5 bytes for the file ending with tar.bz2
Tar-xjf all.tar.bz2
6) for files ending with. Z
Uncompress all. Z
72.16.tar. Z
Tar-xzf all.tar. Z
In addition, Linux has corresponding methods to decompress the compressed files .zipand .rar in Windows:
1)for. Zip
Linux provides zip and unzip programs, Zip is a compression program, and unzip is a decompression program. They have many Parameter options. Here we will only give a brief introduction and give examples to illustrate their usage:
# Zip all.zip *. jpg
This command compresses all .jpg files into a zip package.

# Unzip all.zip
This command decompress all files in all.zip.

2XX vs. .rar
To process the. rar file in linux, you need to install RAR for Linux, which can be downloaded from the Internet, but remember, rar for Linux
Not free; then install:
# Tar-xzpvf rarlinux-3.2.0.tar.gz
# Cd RAR
# Make
After installation, there will be two programs, RAR and unrar. rar is a compression program, and unrar is a decompression program. They have many Parameter options. Here we will only give a brief introduction and give examples to illustrate their usage:
# Rar a all *. jpg
This command is to compress all. jpg files into a rarpackage named all.rar. the program will automatically append the. rar extension name to the package name.
# Unrar e all.rar
This command is to extract all files from all.rar.
So far, we have introduced tar, Gzip, gunzip, Bzip2, bunzip2, compress, uncompress,
You should be able to use zip, unzip, rar, unrar, and other programs.
Decompress the 10 types of compressed files.
You don't need to worry about downloading a software without knowing how to solve it in Linux. In addition, the above method is basically effective for Unix.
This article describes the Linux compressed program tar, Gzip, gunzip, Bzip2, bunzip2, compress, uncompress, zip,
Unzip, rar, unrar, and other programs, and how to use them
To perform operations on the 10 types of compressed files.