write
Send messages to logged-in users
TLDR
Send a message to a user on a specific terminal
$ write [username] [terminal_id]
Send message to user on tty5$ write [username] tty5
Send message to user on pseudo terminal$ write [username] pts/5
SYNOPSIS
write user [ttyname]
DESCRIPTION
write allows you to communicate with other users by copying lines from your terminal to theirs. When you run write, the user receives a message indicating who is writing. You can then type your message, line by line, which appears on their terminal.Press Ctrl+D (EOF) or Ctrl+C to end the message session. Use the who command to find terminal IDs of logged-in users.
CAVEATS
The recipient must have their terminal writable (use mesg y). If the user is logged in on multiple terminals and ttyname is not specified, write picks the terminal with the shortest idle time. Only works for users on the same system.
