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.\" @(#)wall.1 6.5 (Berkeley) 4/23/91
.\"
.\" Modified for Linux, Mon Mar 8 18:07:38 1993, faith@cs.unc.edu
.\"
.Dd April 2011 " "
.Dt WALL(1) "" "User Commands"
.Os util-linux
.Sh NAME
.Nm wall
.Nd write a message to users
.Sh SYNOPSIS
.Nm wall
.Op Ar -n
.Op Ar -t TIMEOUT
.Op Ar file
.Sh DESCRIPTION
.Nm Wall
displays the contents of
.Ar 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.
.Pp
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.
.Pp
Reading from a file is refused when the invoker is not superuser
and the program is suid or sgid.
.Sh OPTIONS
.Bl -tag -width Fl
.It Fl n, Fl Fl nobanner
Supress banner
.It Fl t, Fl Fl timeout Ar 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.
.It Fl V, Fl Fl version
Output version and exit.
.It Fl h, Fl Fl help
Output help and exit.
.Sh SEE ALSO
.Xr mesg 1 ,
.Xr talk 1 ,
.Xr write 1 ,
.Xr shutdown 8
.Sh HISTORY
A
.Nm
command appeared in
.At v7 .
.Sh AVAILABILITY
The wall command is part of the util-linux package and is available from
ftp://ftp.kernel.org/pub/linux/utils/util-linux/.
