wall(1m) [opensolaris man page]

wall(1M)						  System Administration Commands						  wall(1M)

NAME

       wall - write to all users

SYNOPSIS

       /usr/sbin/wall [-a] [-g grpname] [filename]

DESCRIPTION

       wall reads its standard input until an end-of-file. It then sends this message to all currently logged-in users preceded by:

	 Broadcast Message from ...

       If  filename is given, then the message is read in from that file. Normally, pseudo-terminals that do not correspond to rlogin sessions are
       ignored. Thus, when using a window system, the message appears only on the console window. However, -a will send the message even  to  such
       pseudo-terminals.

       It is used to warn all users, typically prior to shutting down the system.

       The sender must be superuser to override any protections the users may have invoked See mesg(1).

       wall runs setgid() to the group	ID tty, in order to have write permissions on other user's terminals. See setuid(2).

       wall  will  detect non-printable characters before sending them to the user's terminal. Control characters will appear as a  " ^ " followed
       by the appropriate ASCII character; characters with the high-order bit set will appear in "meta" notation.  For	example,  `03'  is  dis-
       played as `^C' and  `372' as  `M-z'.

OPTIONS

       The following options are supported:

       -a	     Broadcast message to the console and pseudo-terminals.

       -g grpname    Broadcast to the users in a specified group only, per the group database (see group(4)).

ENVIRONMENT VARIABLES

       If  the	LC_* variables (LC_CTYPE, LC_TIME, LC_COLLATE, LC_NUMERIC, and LC_MONETARY) are not set in the environment, the operational behav-
       ior of wall for each corresponding locale category is determined by  the value of the LANG environment variable. See environ(5). If  LC_ALL
       is  set, its contents are used to override both the  LANG and the other LC_* variables. If none of the above variables are set in the envi-
       ronment, the "C" (U.S. style) locale determines how wall behaves.

FILES

       /dev/tty*

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------------------------------------+
       |ATTRIBUTE TYPE		      ATTRIBUTE VALUE		   |
       |Availability		      SUNWcsu			   |
       +-----------------------------------------------------------+

SEE ALSO

       mesg(1), write(1), setuid(2), attributes(5), environ(5)

NOTES

       wall displays ``Cannot send to ...'' when the open on a user's tty file fails.

SunOS 5.11							    13 Jul 1994 							  wall(1M)

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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
       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

       -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

       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)

Linux and UNIX Man Pages

wall(1m) [opensolaris man page]

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