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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