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@(#)login.1 8.1 (Berkeley) 6/9/93
$FreeBSD: head/usr.bin/login/login.1 21673 1997-01-14 07:20:47Z jkh $
.Dd June 9, 1993 .Dt LOGIN 1 .Os BSD 4 .Sh NAME .Nm login .Nd log into the computer .Sh SYNOPSIS .Nm login .Op Fl fp .Op Fl h Ar hostname .Op Ar user .Sh DESCRIPTION The .Nm login utility logs users (and pseudo-users) into the computer system.
p If no user is specified, or if a user is specified and authentication of the user fails, .Nm login prompts for a user name. Authentication of users is done via passwords.
p The options are as follows: l -tag -width Ds t Fl f The .Fl f option is used when a user name is specified to indicate that proper authentication has already been done and that no password need be requested. This option may only be used by the super-user or when an already logged in user is logging in as themselves. t Fl h The .Fl h option specifies the host from which the connection was received. It is used by various daemons such as .Xr telnetd 8 . This option may only be used by the super-user. t Fl p By default, .Nm login discards any previous environment. The .Fl p option disables this behavior. .El
p If the file
a /etc/nologin exists, .Nm login displays its contents to the user and exits. This is used by .Xr shutdown 8 to prevent users from logging in when the system is about to go down.
p If the file
a /etc/login.access exists, .Nm login checks to see if the user and host pair are specifically allowed or denied access.
p If the file
a /etc/fbtab exists, .Nm login changes the protection and ownership of certain devices specified in this file.
p Immediately after logging a user in, .Nm login displays the system copyright notice, the date and time the user last logged in, the message of the day as well as other information. If the file .Dq Pa .hushlogin exists in the user's home directory, all of these messages are suppressed. This is to simplify logins for non-human users, such as .Xr uucp 1 . .Nm Login then records an entry in the .Xr wtmp 5 and .Xr utmp 5 files and executes the user's command interpretor.
p Login enters information into the environment (see .Xr environ 7 ) specifying the user's home directory (HOME), command interpreter (SHELL), search path (PATH), terminal type (TERM) and user name (both LOGNAME and USER).
p The standard shells, .Xr csh 1 and .Xr sh 1 , do not fork before executing the .Nm login utility. .Sh FILES l -tag -width /var/mail/userXXX -compact t Pa /etc/fbtab changes device protections t Pa /etc/motd message-of-the-day t Pa /etc/nologin disallows logins t Pa /etc/login.access login access control table t Pa /var/run/utmp current logins t Pa /var/log/wtmp login account records t Pa /var/mail/user system mailboxes t Pa .hushlogin makes login quieter .El .Sh SEE ALSO .Xr chpass 1 , .Xr passwd 1 , .Xr rlogin 1 , .Xr getpass 3 , .Xr fbtab 5 , .Xr login.access 5 , .Xr utmp 5 , .Xr environ 7 , .Xr nologin 8 .Sh HISTORY A .Nm login appeared in .At v6 .