wall

WALL(1)                          User Commands                         WALL(1)

NAME
       wall - write a message to all users

SYNOPSIS
       wall [-n] [-t timeout] [-g group] [message | file]

DESCRIPTION
       wall  displays  a  message, or the contents of a file, or otherwise its
       standard input, on the terminals of all currently logged in users.  The
       command  will  wrap  lines  that  are longer than 79 characters.  Short
       lines are whitespace padded to have 79 characters.   The  command  will
       always put a carriage return and new line at the end of each line.

       Only  the superuser can write on the terminals of users who have chosen
       to deny messages or are using a program which automatically denies mes-
       sages.

       Reading  from  a  file is refused when the invoker is not superuser and
       the program is set-user-ID or set-group-ID.

OPTIONS
       -n, --nobanner
              Suppress the banner.

       -t, --timeout timeout
              Abandon the write attempt to the terminals  after  timeout  sec-
              onds.   This  timeout  must  be a positive integer.  The default
              value is 300 seconds, which is a legacy from the time when  peo-
              ple ran terminals over modem lines.

       -g, --group group
              Limit  printing  message  to members of group defined as a group
              argument.  The argument can be group name or GID.

       -V, --version
              Display version information and exit.

       -h, --help
              Display help text and exit.

NOTES
       Some sessions, such as wdm, that  have  in  the  beginning  of  utmp(5)
       ut_type  data a ':' character will not get the message from wall.  This
       is done to avoid write errors.

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 Linux Kernel Archive <https://www.kernel.org/pub/linux/utils/util-
       linux/>.

util-linux                        August 2013                          WALL(1)