xenial (1) wall.1.gz

NAME

       wall - write a message to all users

SYNOPSIS

       wall [-n] [-t timeout] [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 messages.

       Reading from a file is refused when the invoker is not superuser and the program is suid or sgid.

OPTIONS

       -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.

       -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  ⟨ftp://
       ftp.kernel.org/pub/linux/utils/util-linux/⟩.