debian man page for wall

WALL(1) 							   User Commands							   WALL(1)

NAME
     wall -- write a message to users

SYNOPSIS
     wall [-n] [-t TIMEOUT] [file]

DESCRIPTION
     Wall displays the contents of file or, by default, its standard input, on the terminals of all currently logged in users. The command will
     cut over 79 character long lines to new lines. Short lines are white space padded to have 79 characters. The command will always put carriage
     return and new line at the end of each line.

     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.

OPTIONS
     -n, --nobanner
		 Supress banner

     -t, --timeout TIMEOUT
		 Write timeout to terminals in seconds. Argument must be positive integer. Default value is 300 seconds, which is a legacy from
		 time when people ran terminals over modem lines.

     -V, --version
		 Output version and exit.

     -h, --help  Output help and exit.

SEE ALSO
     mesg(1), talk(1), write(1), shutdown(8)

HISTORY
     A wall command appeared in Version 7 AT&T UNIX.

AVAILABILITY
     The wall command is part of the util-linux package and is available from ftp://ftp.kernel.org/pub/linux/utils/util-linux/.

util-linux							   April 2011								util-linux