Linux Online User Communication

1,/ETC/MOTD file
The file is the message of today (bulletin board information), and each time the user logs in, the contents of the/ETC/MOTD file are displayed in the user's terminal. System administrator can edit system activity messages in Files
That is, like a bulletin board, announcement information

But if the boot goes into the graphical interface, it won't get

2,/etc/issue file
The document is similar to/ETC/MOTD.

The main difference is: remote user login (network or port)/etc/issue content will be displayed before login
Content in/ETC/MOTD will be displayed after login


3,write command
You can send messages to online users via the Write command
Write username [TTY]
If a user logs on multiple times, the TTY parameter specifies the terminal to be sent
The user must log on to the system, otherwise it will prompt not logged in. User login can be viewed through the WHO command and then finished by pressing CTRL+D

You can also use write for users on your network:
Write [email protected] Send message to a user on Host B
You can list all logged-on users on the LAN with the Rusers command first

4,wall command
The wall command is used to send information to all users in the system wall that is write all
Wall
You can use Rwall to send information to all users on the LAN first

5,talk command
This command can be implemented with another user (must log on) to implement the dialog
Talk username

6,MESG command
Users can refuse to accept information to prevent interruption of work, mesg N can do, of course, except the omnipotent Superuser root
Mesg-y is to accept

7,ytalk
Talk to other users, and if you are talking to other host users, you need to add IP or host name

8,uux
Executing instructions on the remote UUCP host

9,uustat
Show the current status of UUCP