1 03/11/76 login, l
2
3 Function: The login command is used to gain access to the Multics
4 system. First, the user must dial the appropriate number to activate
5 the terminal and wait until a message is printed by the answering
6 service. The login command is actually a request to the answering
7 service to start the user identification and process creation
8 procedures. Therefore, this command can only be issued from a terminal
9 connected to the answering service; that is, one that has just dialed
10 up, or one that has been returned to the answering service after a
11 session terminated with a hello command.
12
13
14 The login command requests a password from the user and attempts to
15 ensure either that the password does not appear at all on the user's
16 terminal or that it is thoroughly hidden in a string of cover-up
17 characters. The password is a string of one to eight letters and/or
18 integers associated with the Person_id.
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20
21 After the user responds with his password, the Multics system looks up
22 the Person_id and the password in its tables and verifies that the
23 Person_id is valid and that the password given matches the registered
24 password. If these tests succeed, and if the user is not already
25 logged in, the load control mechanism is consulted to determine if
26 allowing the user to log in would overload the system.
27
28
29 Syntax: login Person_id -control_args
30
31
32 where:
33
34 1. Person_id is the user's registered personal
35 identifier. This argument must be
36 supplied.
37
38
39 2. control_args can be selected from the following:
40
41 -brief, -bf suppresses messages associated with a
42 successful login.
43
44 -change_password, changes the user's password to a newly
45 -cpw given one. Multics asks for the old one
46 before requesting the new. If the old
47 password is correct, the new password
48 replaces it for subsequent logins and the
49 message "password changed" is printed.
50 The user should not type the new password
51 as part of the control argument.
52
53 -no_print_off, -npf overtypes a string of characters to
54 provide a black area for the user to type
55 his password necessary only for users
56 whose terminals do not have
57 print-suppression capabilities.
58
59 -terminal_type XX, sets the user's terminal type to XX,
60 -ttp XX where XX is one of the types listed for the
61 corresponding control argument of the
62 set_tty command.
63
64 -modes XX sets the modes for terminal I/O according
65 to XX. For a description of this
66 argument, see the corresponding argument
67 of set_tty.
68
69
70 Examples:
71
72 In the examples below, the user's password is shown even though in
73 most cases Multics either prints a string of cover-up characters to
74 "hide" the password or temporarily turns off the printing mechanism of
75 the user's terminal.
76
77
78 Probably the most common form of the login request is to specify
79 just the Person_id and the password as:
80
81
82 ! login Jones
83 Password:
84 ! mypass
85
86
87 To set the tabs and crecho I/O modes so the terminal uses tabs
88 rather than spaces where appropriate on output and echoes a carriage
89 return when a line feed is typed, type:
90
91
92 ! login Jones -modes tabs,crecho
93 Password:
94 ! mypass
95
96
97 To change the password from mypass to newpass, type:
98
99
100 ! login Jones -cpw
101 Password:
102 ! mypass
103 New Password:
104 ! newpass
105 Password changed.