sunos man page for wall

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 5.10							    13 Jul 1994 							  wall(1M)