wall

 

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 Maintenance 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  sys-
      tem,  the  message  appears only on the console window. How-
      ever,  -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, `\003'  is  displayed  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 a specified group only.
 
 ENVIRONMENT VARIABLES
      If the  LC_*  variables  (  LC_CTYPE,  LC_TIME,  LC_COLLATE,
      LC_NUMERIC,  and  LC_MONETARY )  are not set in the environ-
      ment, the operational behavior of wall for each  correspond-
      ing 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
 
 
 
 SunOS 5.8           Last change: 13 Jul 1994                    1
 
 
 
 
 
 
 Maintenance Commands                                     wall(1M)
 
 
 
      LC_* variables. If none of the above variables  are  set  in
      the  environment, the "C" (U.S. style) locale determines how
      wall behaves.
 


FILES
      /dev/tty*
 


ATTRIBUTES
      See attributes(5) for descriptions of the  following  attri-
      butes:
 
      ____________________________________________________________
     |       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 5.8           Last change: 13 Jul 1994                    2
 
 
 

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