"Linux" Learning 2

The 6th chapter of the Book of Bird Brother

File permissions:

^                ^     ^      ^        ^              ^                 ^

1 2 3 4 5 6 7

The file has the owner of the file, the concept of the user group the file belongs to.

1.10 letters indicates file permissions are divided into 4 sections

D R_x R_x _ _ _ _

First Letter: Indicates file type

d directory,-file, l connection file, B storage interface device, c serial port device

第2-4个 Letter: Indicates that the file owner's permissions to the file are readable R writable W executable x does not have permission in _

第5-7个 Letter: Represents the user group to which the file belongs permissions

第8-10个 Letter: Indicates the permissions of other users on the file

D R_x R_x _ _ _ Represents a directory, the file owner can read executable, file user group user readable executable, other users unreadable non-writable not executable

2. Number of file connections

3. Owner

4. User groups

5. File Capacity Unit B

6. Last Modified Date

7. File name. Start representing hidden files

To change the properties of a file:

chgrp: Changing the user group to which the file belongs

If you change the Test1.txt to the Users user group: CHGRP users Text1.txt

chown: Changing the file owner can also change the user group and user name

If you change the test1.txt to Kuang User: Chown Kuang text1.txt

Change the test1.txt to the users user group Kuang User: Chown kuang:users test1.txt (can also use. To replace:)

chmod: Changing the permissions of a file

The first permission given with the number R 4 W 2 x 1 is the value in these three numbers

such as chmod test1.txt: The Test1.txt attribute changed to rw-------

Second, the use of symbols

Three types of identities represent U:user G:group o:others A:all

+: Join Permissions-: Remove permissions =: Set permissions

such as chmod u=rwx test1.txt the Test1.txt user rights set to rwx other unchanged

Some other commands to use:

cat: read out file contents such as Cat Test1.txt

su: Switch user identities such as Su Kuang

mkdir: Create new directory

Go to Folder:

Absolute path cd/home/name/name with/start, all paths are typed

Relative path CD./name. Represents the current directory, which represents a sub-file into the current directory

Cd.. Return to the previous level of the directory, note: And there's a space between the CDs.

"Linux" Learning 2