linux-Seventh Lesson Notes-[permissions]

Rights Management

Linux permissions:

R: Read

W: Write

X: Execute

-rw-r--r--1 root root

-File (d stands for directory)

3-bit one set

The first 3 bits represent the owner's permission rwx

Intermediate 3-bit delegate permissions for group RWX

The latter 3 bits represent the rights of other users rwx

R 4 W 2 x 1

Default permissions for new files

0664-----Rw-rw-r--.

Maximum privilege is 0666

Default permissions for new directories

0755----drwx-r-xr-x.

Maximum privilege is 0777

Modify Permissions: chmod

Usage: chmod File/directory

Chmod 664 1.txt

[email protected] ~]# ll 1.txt

-rw-r--r--1 root root 0 14:01 1.txt

[Email protected] ~]# chmod 664 1.txt

[email protected] ~]# ll 1.txt

-rw-rw-r--1 root root 0 14:01 1.txt

Chmod u+r 1.txt (-w/x) owner can be added and reduced

Chmod g+r 1.txt (-w/x) group can be added and reduced

Chmod o+r 1.txt (-w/x) other available plus and minus

Modified genera Group: Chown

Usage: chown [owner: Genus] 1.txt

For example:

[email protected] ~]# ll 1.txt

-rw-rw-r--1 root root 0 14:01 1.txt

[Email protected] ~]# Useradd test

[Email protected] ~]# chown test:test 1.txt

[email protected] ~]# ll 1.txt

-rw-rw-r--1 Test test 0 14:01 1.txt

[Email protected] ~]# chown root 1.txt

[email protected] ~]# ll 1.txt

-rw-rw-r--1 root Test 0 14:01 1.txt

[Email protected] ~]# Chown:root 1.txt

[email protected] ~]# ll 1.txt

-rw-rw-r--1 root root 0 14:01 1.txt

linux-Seventh Lesson Notes-[permissions]