xref: /freebsd/usr.bin/login/login.1 (revision fbf96e52bbd90bbbb9c9e2ae6fbc101fa6ebd080)
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32.\"	@(#)login.1	8.2 (Berkeley) 5/5/94
33.\" $FreeBSD$
34.\"
35.Dd May 5, 1994
36.Dt LOGIN 1
37.Os
38.Sh NAME
39.Nm login
40.Nd log into the computer
41.Sh SYNOPSIS
42.Nm
43.Op Fl fp
44.Op Fl h Ar hostname
45.Op Ar user
46.Sh DESCRIPTION
47The
48.Nm
49utility logs users (and pseudo-users) into the computer system.
50.Pp
51If no user is specified, or if a user is specified and authentication
52of the user fails,
53.Nm
54prompts for a user name.
55Authentication of users is configurable via
56.Xr pam 8 .
57Password authentication is the default.
58.Pp
59The following options are available:
60.Bl -tag -width indent
61.It Fl f
62When a user name is specified, this option indicates that proper
63authentication has already been done and that no password need be
64requested.
65This option may only be used by the super-user or when an already
66logged in user is logging in as themselves.
67.It Fl h
68Specify the host from which the connection was received.
69It is used by various daemons such as
70.Xr telnetd 8 .
71This option may only be used by the super-user.
72.It Fl p
73By default,
74.Nm
75discards any previous environment.
76The
77.Fl p
78option disables this behavior.
79.El
80.Pp
81If the file
82.Pa /etc/login.access
83exists,
84.Nm
85checks to see if the user and host pair are specifically allowed or denied
86access.
87Login access may also be controlled via the login class, which provides
88allow and deny records based on time, tty and remote host name.
89.Pp
90If the file
91.Pa /etc/fbtab
92exists,
93.Nm
94changes the protection and ownership of certain devices specified in this
95file.
96.Pp
97Immediately after logging a user in,
98.Nm
99displays the system copyright notice, the date and time the user last
100logged in, the message of the day as well as other information.
101If the file
102.Pa .hushlogin
103exists in the user's home directory, all of these messages are suppressed.
104This is to simplify logins for non-human users, such as
105.Xr uucp 1 .
106.Pp
107The
108.Nm
109utility enters information into the environment (see
110.Xr environ 7 )
111specifying the user's home directory (HOME), command interpreter (SHELL),
112search path (PATH), terminal type (TERM) and user name (both LOGNAME and
113USER).
114Other environment variables may be set due to entries in the login
115class capabilities database, for the login class assigned in the
116user's system passwd record.
117The login class also controls the maximum and current process resource
118limits granted to a login, process priorities and many other aspects of
119a user's login environment.
120.Pp
121Some shells may provide a builtin
122.Nm
123command which is similar or identical to this utility.
124Consult the
125.Xr builtin 1
126manual page.
127.Sh FILES
128.Bl -tag -width ".Pa /etc/login.access" -compact
129.It Pa /etc/fbtab
130changes device protections
131.It Pa /etc/login.access
132login access control table
133.It Pa /etc/login.conf
134login class capabilities database
135.It Pa /etc/motd
136message-of-the-day
137.It Pa /var/mail/user
138system mailboxes
139.It Pa \&.hushlogin
140makes login quieter
141.It Pa /etc/auth.conf
142configure authentication services
143.It Pa /etc/pam.conf
144.Nm
145uses
146.Pa /etc/pam.conf
147entries with service name
148.Dq login
149.El
150.Sh SEE ALSO
151.Xr builtin 1 ,
152.Xr chpass 1 ,
153.Xr csh 1 ,
154.Xr passwd 1 ,
155.Xr rlogin 1 ,
156.Xr getpass 3 ,
157.Xr fbtab 5 ,
158.Xr login.access 5 ,
159.Xr login.conf 5 ,
160.Xr environ 7 ,
161.Xr pam 8
162.Sh HISTORY
163A
164.Nm
165utility appeared in
166.At v6 .
167