We use wall to broadcast any message to all users logged in at any point of time through terminal
We can use ‘write’ command to send or write a message to a particular user through terminal.
root@server1056 [/root]# w
18:23:38 up 22 days, 17:03, 3 users, load average: 0.47, 0.22, 0.12
USER TTY FROM LOGIN@ IDLE JCPU PCPU WHAT
root pts/0 1x.3x.7x.53-sta 17:48 0.00s 0.06s 0.06s -bash
root pts/3 12x.16x.6x.138 16:14 40:29 0.19s 0.19s -bash
obama pts/4 adsl-7x-4x-1x-18 Mon18 47:18m 0.00s 0.01s sshd: obama [priv]
root@server1056 [/root]# write obama pts/4
hey bud, please call me, I lost your no. since my cell was stolen.
After typing “write obama pts/4” as the command hit enter key once,
then type your message and hit your enter key once to push the message.
then hit ctrl+d to exit out of the write session.