File Operations
1, ls -l - Details show the current directory
2, ls -l -h - shows in detail the current directory files, and file size to more clearly see the way
3, mkdir - create a directory
4, mkdir -p directory name - create directories recursively
5 ,. - represents the current directory
6 .. - on behalf of parent directory
7, cd ../-- return to the previous level *
8, pwd - show current directory absolute path
9, touch the file name - Create a file
10, mv file you want to move a moving target address - moving files, multi-layer address to write the whole directory
11、mv test.txt test.txt.bak 改名
File Viewer
12, cp abc.text a copy command
13, mv * .txt a - all move to a directory
14, cp * .txt ../ copy all files to the parent directory txt
15, mv -f * .txt a - not prompted to overwrite the file
16, bin - execute directory
17, sbin - system command
18, etc - configuration files
19, tmp - temporary directory
20, opt - file directory
21, cd ~ home directory
22, cd / back to the root directory
23, cat aaa - View all files are smaller files can be displayed full
24, more aaa - in proportion to view files
25, less aaa - you can view the row direction keys, see the process by q quit
26, head aaa - from the beginning to see
27, head -6 aaa - See the first six rows
28, tail -f aaa - start with the tail, dynamic view files
29, tail -20 aaa-- view the end of the line 20
30, tail aaa default view line 10
31, cat aaa> test - Redirection
32, cat aaa >> test - Append
33, echo '11111' - Print 1111
34, echo '1111' >> aaa - 1111 log appended
Competence
liunx is a multi-user multi-tasking
etc directory
cat / etc / passwd store user information
Each row is a user, the user name separated by a colon process : password : user ID : Group ID : Annotated Description : home directory : login Shell
Password is not written in the current file
Password positions: head / etc / shadow store user is a user password each row and separated by: --- username: password
Login : password encryption : Last Modified : minimum time interval : maximum time interval : Warning time : No Time : Time : Logo
head /etc/group
Group Name : Password : Group ID : the group user list
Create a user
useradd test
passwd 123456
123456
After creating a user - see the following three files are inserted into the data
cat /etc/passwd
--testjq:x:1005:1005::/home/testjq:/bin/bash
tail -l /etc/shadow
--testjq: !!: 18045: 0: 99999: 7 ::: // !! representatives did not set a password
--ningjq001: $ 1 $ Nkq.wHEQ $ RTyrBRkh1tPj7z / dGqwI30: 18044: 0: 99999: 7 ::: // password
tail -1 /etc/group testjq:x:1005:
Change the user password: passwd testjq user
enter password
Enter the password again
[root@VM_0_7_centos ~]# su test
[test@VM_0_7_centos root]$
$：代表普通用户
#：代表管理员用户
普通用户没有根目录权限
权限
-rw 所属用户权限 r-- 组权限 r-- 其他用户权限
第一位代表当前文件的类型
d:代表目录
-：代表文件
l：代表软连接
rwx ：读、写、执行
r -4
w-2
x-1
chmod 777 文件名 --修改目录的文件权限
进入目录就得有读、又有执行权限
恢复权限
chmod o=- 文件名 --将文件other改成没有任何权限
chmod g+x --给组追加权限
chown root：aaa 修改文件的拥有值