wall(1M)                                                           wall(1M)

NAME
     wall - write to all users

SYNOPSIS
     /usr/sbin/wall

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 ...

     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() [see setuid(2)] to the group ID tty, in order to
     have write permissions on other user's terminals.

     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, \003 is displayed as ^C and
     \372 as M-z.

LOCALE
     The LCMESSAGES environment variable governs the language in which
     message texts are displayed.

     If LCMESSAGES is undefined or is defined as the null string, it
     defaults to the value of LANG. If LANG is likewise undefined or null,
     the system acts as if it were not internationalized.

     If any of the locale variables has an invalid value, the system acts
     as if none of the variables was set.

     The LCALL environment variable governs the entire locale. LCALL
     takes precedence over all the other environment variables which affect
     internationalization.

DIAGNOSTICS
     "Cannot send to ..." when the open on a user's tty file fails.

FILES
     /dev/tty*

SEE ALSO
     mesg(1), write(1).





Page 1                       Reliant UNIX 5.44                Printed 11/98