Basic Linux commands (Continuous updates)

Init 0 --- Shutdown

Init 1 --- logout

Note: Both commands can be run only with the root permission.

Common users get root permissions:

Su

Enter the root password.

PWD --- display path

Copy the file and delete the source file:

MV [source file path and file name] [target file and file name]

The absolute path is expressed by/XXX/xxx. X, And/is required. The relative path is based on the current directory. Where... indicates to roll back to the upper-level directory .. Indicates

Current directory. It can be ../XXX/xxx. X or./XXX/xxx. X.

1.Zip

Linux comes with an unZipProgram can be decompressedFile, The decompression command is:

Unzip filename.zip

A zip program is also provided to compress the zip code.File, Command is

Zip filename.zip files

The file will be compressed to filename.zip.

2.RAR

BecauseRARIt is a paid software, so Linux does not come with this software for pressurization and decompression. You canRARUnder the official website http://www.rarsoft.com

Download the trial version.

After installation, available commands

Unrar e filename.rar decompress the file

RAR a files filename will compress filesinto filename.rar. Note that RAR will automatically add the suffix. rar to your file.

 

File/directory permission setting command: chmod

It is used to change the access permissions of files or directories. This command has two usage methods:

1. Use a text setting method that contains letters and operator expressions

Syntax format: chmod [who] [opt] [mode] File Name/directory name

Which indicates the object, which is one or a combination of the following letters:
U: indicates the file owner.
G: indicates the same group of users.
O: other users
A: indicates all users.

Opt indicates the operation, which can be:
+: Add a permission.
-: Cancel a permission.
=: Grant the given permissions and cancel the original permissions.

Mode indicates the permission:
R: readable
W: writable
X: executable

For example, to add the read and write permissions for file a.txt to users in the same group:

Chmod g + RW a.txt

Ii. digit setting

The number setting rule is simpler: chmod [mode] File Name

The key is the mode value. Many beginners will be confused at the beginning. In fact, it is very simple. We regard rwx as a binary number. If there is one, it indicates that there is no

If the value is 0, rwx R-x r--can be expressed:

111 101 100

Convert each three digits into a decimal number, that is, 754.

For example, we want to grant the permission for the.txt file:

Other users in the same group
Readable is yes
Writable is executable

Then, we first obtain the permission string RW-r -- Based on the table above, and convert it to the binary number 110 110 100, and then convert each three digits into a decimal number,

We get 664, So we run the following command:

Chmod 664 a.txt