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LOGIN(1)		     General Commands Manual			LOGIN(1)

NAME
     login -- log into the computer

SYNOPSIS
     login [-fp] [-h hostname] [user]

DESCRIPTION
     The login utility logs users (and pseudo-users) into the computer system.

     If  no  user  is specified, or if a user is specified and authentication of
     the user fails, login prompts for a user name.  Authentication of users  is
     done via passwords.

     The options are as follows:

     -f      The  -f  option  is  used when a user name is specified to indicate
	     that proper authentication has already been done and that no  pass-
	     word 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.

     -h      The  -h option specifies the host from which the connection was re-
	     ceived.  It is used by various daemons such  as  telnetd(8).   This
	     option may only be used by the super-user.

     -p      By default, login discards any previous environment.  The -p option
	     disables this behavior.

     If  the  file  /var/run/nologin  exists, login displays its contents to the
     user and exits.  This is used by shutdown(8) to prevent users from  logging
     in when the system is about to go down.

     If  the  file /etc/login.access exists, login checks to see if the user and
     host pair are specifically allowed or denied access.  Login access may also
     be controlled via the login class, which provides allow  and  deny  records
     based on time, tty and remote host name.

     If  the  file /etc/fbtab exists, login changes the protection and ownership
     of certain devices specified in this file.

     If the file /etc/skeykeys exists, login will offer S/key  password  valida-
     tion  if the user has an entry in the file.  /etc/skey.access controls from
     which hosts and/or networks the use of S/key passwords are obligated.

     Immediately after logging a user in, 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  ".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 uucp(1).   The  login  utility
     then  records  an	entry  in the wtmp(5) and utmp(5) files and executes the
     user's command interpreter.

     The login utility enters information into the environment (see  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).   Other environment variables may be set due to entries in the login
     class capabilities database, for the login class  assigned  in  the  user's
     system  passwd  record.  The login class also controls the maximum and cur-
     rent process resource limits granted to a	login,	process  priorities  and
     many other aspects of a user's login environment.

     Some shells may provide a builtin login command which is similar or identi-
     cal to this utility.  Consult the builtin(1) manual page.

FILES
     /etc/fbtab 	changes device protections
     /etc/login.access	login access control table
     /etc/login.conf	login class capabilities database
     /etc/motd		message-of-the-day
     /var/run/nologin	disallows logins
     /etc/skey.access	skey password control table
     /etc/skeykeys	skey password database
     /var/run/utmp	current logins
     /var/log/lastlog	last login account records
     /var/log/wtmp	login account records
     /var/mail/user	system mailboxes
     .hushlogin 	makes login quieter
     /etc/auth.conf	configure authentication services
     /etc/pam.conf	if  login  is  configured  with  PAM  support,	it  uses
			/etc/pam.conf entries with service name "login"

SEE ALSO
     builtin(1), chpass(1), csh(1), passwd(1), rlogin(1),  skey(1),  getpass(3),
     fbtab(5),	 login.access(5),   login.conf(5),  nologin(5),  skey.access(5),
     utmp(5), environ(7), nologin(8), pam(8)

HISTORY
     A login utility appeared in Version 6 AT&T UNIX.

FreeBSD 4.9			   May 5, 1994				LOGIN(1)

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