wall(1) — Linux manual page

WALL(1)                       User Commands                      WALL(1)

NAME         top

       wall - write a message to all users

SYNOPSIS         top

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

DESCRIPTION         top

       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 messages.

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

OPTIONS         top

       -n, --nobanner
              Suppress the banner.

       -t, --timeout timeout
              Abandon the write attempt to the terminals after timeout
              seconds.  This timeout must be a positive integer.  The
              default value is 300 seconds, which is a legacy from the
              time when people 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         top

       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.

HISTORY         top

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

SEE ALSO         top

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

AVAILABILITY         top

       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/⟩.

COLOPHON         top

       This page is part of the util-linux (a random collection of Linux
       utilities) project.  Information about the project can be found
       at ⟨https://www.kernel.org/pub/linux/utils/util-linux/⟩.  If you
       have a bug report for this manual page, send it to
       util-linux@vger.kernel.org.  This page was obtained from the
       project's upstream Git repository
       ⟨git://git.kernel.org/pub/scm/utils/util-linux/util-linux.git⟩ on
       2020-12-18.  (At that time, the date of the most recent commit
       that was found in the repository was 2020-12-17.)  If you
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       manual page), send a mail to man-pages@man7.org

util-linux                     August 2013                       WALL(1)

Pages that refer to this page: mesg(1),  systemctl(1),  systemd-ask-password(1),  systemd-tty-ask-password-agent(1),  halt(8),  shutdown(8),  systemd-ask-password-console.service(8),  telinit(8)

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