man wall (Commandes) - wall

NAME

wall - write a message to users

wall [file]

Wall

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.

Reading from a file is refused when the invoker is not superuser and the program is suid or sgid.

A command appeared in