Introduction to Linux, package and take away what you need! !

Linux basics

1. What is Linux (belonging to the GNU open source organization)?
   Linux is a kernel, equivalent to the human brain, responsible for system programs and hardware allocation and scheduling.
2. What is open source?
   Open source is not free and not charged in the sense of our understanding, but open source code!
3. What is a shell?
   The system I use is Red Hat 8 Enterprise Edition, so the shell used by default in RHEL8 is the bash
   shell, which is equivalent to a big box, which protects the kernel internally and provides an interface for communicating with the operating system externally.
   Basic operation of the shell:
   1 Directly right-click to open in terminal
   2 Set the shortcut key settings→Devices→Keyboard→the bottom + number
   3 After opening a shell, if you want to open a new shell, you can create a shortcut key ctrl+shift+N
   4 Direct use of the command gone-terminal
   shell command line prompt meaning
   [root@localhost Desktop]#
   1 root user running the shell
   2 @ separator
   3 system host name of the current host minus the short name of the domain name
   4 Desktop current directory name
   5 identity prompt Character # means root user $ means ordinary user
   shell basic operation command
   1 ctrl+shift+c copy
   2 ctrl+shift+v paste
   3 ctrl+c cancel command execution
   4 ctrl+d close shell
4. Switch user operation

su - 用户名

The operation screenshot is as follows:

5. The basic purpose of the viewing command, but if there is nothing appropriate during the viewing process, you need to switch the user to the root user and use the mandb command to update the help data.

For example, view the meaning of the ls command

whatis ls
#出现nothing appropriate，切换成管理员用户，使用如下命令。
mandb

6. The use of
   help commands The help commands can be divided into two types, one is the command ±-help, the other is the man command, and the
   first is to display all the help content directly. The second type can be q exit; G quickly moves to the end of man, g quickly moves to the top of man; / keyword to find the corresponding content, n matches down, and N matches up.
   Help content: [] content can be added or not,… means any number of content, <> elements that must be added when the command is executed.

ls --help
man ls

Example date:

#1.2天后是什么时间
date -d 2day

7. History call command

#历史信息调用
history 
#历史信息删除，但是要彻底删除需要进入home文件夹下的隐藏文件夹，删除.bash_history文件内容
history -c

Clear history

8. Set shortcut keys
   settings→Devices→Keyboard→+ at the bottom
   

9. Language setting
   settings→Region&Language The above is the system language setting, the lower is the input method setting