Linux system Architecture
Linux is an inverted tree structure
Everything in Linux is a file.
These files are at the top of the system directory "/"/is the root directory
/directory Below is a level two directory these directories are automatically created when the system is installed
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2. The role of level two directories
/bin # #二进制可执行文件也就是系统命令
/sbin # #系统管理命令存放位置
/Boot # #启动分区, responsible for system startup
/Dev # #设备管理文件
/etc # #大多数系统管理文件
/Home # #普通用户的家目录
/lib # #32位系统库文件存放位置
/LIB64 # #64位系统库文件存放位置
/media # #系统临时设备挂载点
/MNT # #系统临时设备挂载点
/run # #系统临时设备挂载点
/OPT # #第三方软件安装位置
/proc # #系统信息
/root # #超级用户家目录
/srv,/var # #系统数据
/sys # #系统管理, mostly about the kernel
/tmp # #系统临时文件存放位置
/usr # #系统用户相关信息数据及用户自定义软件存放位置
3. Addressing the file
(1) Absolute path
File in the real location of the system, the file name begins with "/"
(2) Relative path
The file is abbreviated to a name in the current location, and the name does not start with a/, and the name automatically adds the value displayed by the PWD.
4. Regular expressions
(1) wildcard characters
* # # #匹配0到任意字符
? # # #匹配单个字符
[[: Alpha:]] # # #匹配单个字母
[[: Lower:]] # # #匹配单个小写字母
[[: Upper:]] # # #匹配单个大写字母
[[:d Igit:] # # # #匹配单个数字
[[: Alnum:]] # # #匹配单个数字或字母
[[:p UNCT:] # # # #匹配单个符号
[[: Space:]] # # #匹配单个空格
(2) {} indicates a nonexistent or existing
{1..9} # # #1-9
{A.. F} # # #a-F
{1,3,5} # # #135
{a,c,e} # # #a c E
{1..3} {A.. C} # # #1a 2a 3a 2a 2b 2c 3a 3b 3c multiplication operation
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[] Indicates the existence of the
[A-c] # # #aA BB CC
[A-c] # # #aA或者bB或者c
[1-3] # # #1或者2或者3
[145] # # #1或者4或者5
[^abc]| [!ABC] # # #除了a并且除了b并且除了c
~ # # #当前用户家目录
~username # # #指定的用户家目录
~+ # # #当前目录
~-# # #当前目录之前所在目录
. # # #当前目录
.. # # #当前目录的上一级
Managing input and output
In a Linux system, the standard input is numbered 0, the correct output is numbered 1, and the error output number is 2
Perform "student" with ordinary users in the system
Find/etc-name passwd
Because the student user rights issue will have the following output
Find: '/etc/pki/ca/private ': Permission denied # #没有进入权力, error
Find: '/etc/pki/rsyslog ': Permission denied
Find: '/etc/audit ': Permission denied
/ETC/PASSWD # #正确输出
Find: '/ETC/POLKIT-1/RULES.D ': Permission denied
Find: '/etc/polkit-1/localauthority ': Permission denied
Find: '/etc/dhcp ': Permission denied
Find: '/etc/selinux/targeted/modules/active ': Permission denied
Find: '/etc/lvm/archive ': Permission denied
Find: '/etc/lvm/backup ': Permission denied
Find: '/etc/lvm/cache ': Permission denied
Find: '/ETC/GRUB.D ': Permission denied
/ETC/PAM.D/PASSWD # #正确输出
Find: '/etc/audisp ': Permission denied
Find: '/etc/firewalld ': Permission denied
Find: '/etc/cups/ssl ': Permission denied
Find: '/etc/ipsec.d ': Permission denied
Find: '/etc/libvirt ': Permission denied
Find: '/ETC/SUDOERS.D ': Permission denied
Find: '/etc/named ': Permission denied
2. (1) Output redirection
Find/etc-name passwd > File # #重定向正确输出 >
Find/etc-name passwd 2> fi
Le # #重定向错误输出 2>
Find/etc-name passwd &> File # #重定向所有输出 &>
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Note: 2>,&> will overwrite the contents of the source file.
>file # #清空file
Find/etc-name passwd >> File # #追加正确输出 >>
Find/etc-name passwd 2>> File # #追加错误输出 2>>
Find/etc-name passwd &>> File # #追加所有输出 &>>
Note:>> 2>> &>> does not overwrite the contents of the source file, it will put the corresponding output characters at the end of the file
(2) Input redirection: format input to File
Tr ' A-Z ' A-Z ' < Westos cat > Westos <<eof
HELLO
World
Eof
3. Pipe symbol: |
Pipe, the correct output of the previous command as the standard input for the command following the pipe character
Ls/bin | Wc-l # #统计ls
/bin the number of rows output by the command
The output of the error (STDERR) in the system is not available through the pipeline.
Use 2>&1 to change the wrong output number from 2 to 1.
Tee copy output to specified location
Date |tee file |wc-l # # #tee命令复制date命令的输出到file中, and statistics output line
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4.vim Command Mode # # # #
(1) in Vim's command mode you can configure how VIM works
: Set nu # #行号添加
: Set nonu # #取消行号
: Set mouse=a # #添加鼠标选择
: Set cursorline # #行线显示
The above settings are temporary,
Permanent settings
vim/etc/vimrc ## #此文件为vim的配置文件, at the end of this file add the above parameters, The number of digits added to the file is not required:
(2). The key word search in vim command mode
/keyword
n down match
N up match
(3). The management of characters in vim command mode
( 1. Copying of characters
yl # #复制一个字母
y3l # #复制3个字母
yw # #复制一个单词
y3w # #复制3个单词
yy # #复制一行
y3y # #复制3行
p # #复制完成后按 "P" Paste
(2. Deletion of characters
dl # #删除一个字母
d3l # #删除3个字母
dw ## Delete a word
d3w # #删除3个单词
dd # #删除一行
d3d # #删除3行
(3. Cutting of characters
CL # #剪切一个字母
C3L # #剪切3个字母
CW # #剪切一个单词
C3W # #剪切3个单词
CC # #剪切一行
C3C # #剪切3行
ESC---> P # #剪切过后会进入到插入模式, be sure to exit insert mode when performing a paste action
(4). Vim's Visual Mode # # # # # #
Press "CTRL + V" in command mode to enter the visual mode
In visual mode, you can select characters in the area
Bulk add characters in visual mode
*>> Ctrl + V Select the column to which you want to add characters
*>> Press "I" into insert mode, write the characters to be added
*>> Press ESC
(5). Batch modifier characters # # # #
:%s/original character/replace character # #只替换每一行中出现的第一个原有字符
:%s/original character/replace character/g # #替换所有
:%s/^\ *//g # #把全文行首的空格去掉, "^\ *" indicates the space at the beginning of the line
(6). Vim's split-screen function # # #
Ctrl+w S # # #上下分屏
Ctrl+w V # # #左右分屏
Ctrl+w C # # #关闭光标所在屏幕
Ctrl+w up or down # # #光标移动到指定屏幕
: SP File2 # #同时编辑当前文件和file2
(7). VIM Cursor Movement #####
in command mode
: Number # #移动到指定的行
G # #文件最后一行
GG # #文件第一行
In insert mode
I # #光标所在位置插入
I # #光标所在行行首
A # #光标所在字符的下一个位置
A # #光标所在行行尾
O # #光标所在行下一行
O # #光标所在行上一行
S # #删除光标所在字符插入
S # #删除光标所在行插入
(8). Vim's exit mode
: Q # #当用vim打开文件但没有对字符作任何操作时可直接退出
: q! # #当用vim打开文件并对字符作操作, quit all operations
: Wq # #保存退出
: wq! # #强行保存退出, effective for Superuser and file owner
(9). Vim Handbook # # # #
Vimtutor # #vim的手册
: Q # #退出vimtutor
5.gedit
CTRL + N # #在gedit中打开一个新的tab
Ctrl+s # #保存文件
Ctrl+o # #打开文件
Ctrl+x # #剪切字符
Ctrl + V # #粘贴字符
CTRL + C # #复制字符
Yelp Help:gedit # #gedit的图形手册
This article is from the "13122425" blog, please be sure to keep this source http://13132425.blog.51cto.com/13122425/1950088
Linux Cloud Automation Fundamentals 4 (System architecture, vim, management input and output, regular expressions)