wall

Write a message to users.

Syntax
      wall [-g group] [file]

Key
   -g      Send messages to users in this group.
           This option may be specified multiple times, and any user in any of the specified groups
           will receive the message.

The wall utility displays the contents of file or, by default, its standard input, on the terminals of all currently logged in users. Only the super-user can write on the terminals of users who have chosen to deny messages or are using a program which automatically denies messages.

The wall utility does not recognize multibyte characters.

Examples

Replace spaces in the clipboard text with %20

$ echo Hello World | Wall

“All in all it was just a brick in the wall.
All in all it was all just bricks in the wall” ~ Pink Floyd

Related macOS commands

echo - Display text on screen.
say - Convert text to audible speech.