1 02/21/85  warn, w
 2 
 3 Syntax as a command:  w User_id message
 4 
 5 
 6 Function:  is used to output a message onto a user's terminal,
 7 interrupting whatever other output is being printed.  This command can
 8 be used in ring 4 only.
 9 
10 
11 Arguments:
12 User_id
13    specifies the user to whom the message should be sent.  It may be
14    given in either of these forms:
15 
16          Person_id.Project_id
17          Person_id Project_id
18 
19    The star convention is allowed.
20 message
21    is a string that contains the text of the message to be sent to the
22    user.
23 
24 
25 Notes:  If a user to be warned has specified the -no_warning (-nw)
26 argument at login, no warning message is sent to him, and you are told
27 that the user could not be warned.
28 
29 The warn command should not be used for casual communication since the
30 message is forced into the middle of anything the user is typing,
31 ruining output.  Use the command only when the system is coming down
32 shortly, or is likely to crash, or when you have an urgent message for
33 a particular user who cannot be reached by telephone.