Run Linux commands and get help

2.1. Linux (UNIX) command format

命令 【选项】 【参数】 （command [options] [arguments]）

Each item in the command line is separated by one or more spaces, and the part enclosed in square brackets is optional and can be used as a meta. The specific meanings of each part in the command line are as follows:
command : Tell the Linux operating system what to do (execute).
Options : Describes how the command runs (you can change the function of the command), and the Options section starts with the "-" character
Parameters : Describes what the command affects (actions) (such as a file, a directory, or a paragraph of body text).

2.2, WhoAmI

Command:whoami
View the current user.

Command: Whoam I command
View current user is willing to display the user's terminal as well as the current date and time, and the use of the computer's IP address

2.3. who command w command

Command: who
View the users who are running the current system.

Command:w
：

First explain the meaning of each of the first lines from left to right:
The current time is 8:26:29 seconds.
System has been started (up) for 12 minutes
There are currently 3 users.
The system has submitted 0.00 missions in the last 1 of the
The system has submitted 0.03 missions in the last 10 minutes
The system has submitted 0.05 missions in the last 15 minutes
(load average is the average load, followed by 3 numbers representing the last 1 minutes of load, the last 10-minute load, and the last 15-minute load).
The 3rd line is explained below:
The first 3 columns are the same as the Who am I command and no longer explain
The 4th column ([email protected]) indicates that the dog user logged into the system at 8:25
The 5th column (idle) indicates that the user is not an active user, has been idle for 5 seconds, and if 0.00 indicates that the user is not an idle account, this account is active.
The 6th column (JCPU) indicates that the dog user has so far used 0.02 seconds of CPU time
The 7th column (PCPU) indicates that the program that the dog user is currently running uses 0.01s of CPU time
The 8th column (what) indicates the program that the dog user is currently using. is W

2.4, uname command and with options

Command: uname

Displays the operating system used to display the Linux used

Command: Uname-n

Display the system host name

Command: Uname-i

Displays the hardware platform name of the system used

Command: uname-n-I or Uname-i-n or uname-in or Uname-ni are the same results

This means that the result of the command is independent of the order of the options, that is, the final result is the same regardless of the two options.

Here are a few more options that you might use.
-R:: Displays version information released by the operating system
-S: Displays the operating system name
-M: Display the machine hardware name
-P: Displays the type of the central processing Unit.
-A: Displays all information.

Run Linux commands and get help