## SYNOPSIS

           login [ -p ] [ username ]
           login [ -p ] [ -h host ] [ -f username ] host

## DESCRIPTION

           login  is used when signing onto a system.  If no argument
           is given, login prompts for the username.

           The user is then prompted for  a  password,  where  appro
           prate.  Echoing is disabled to prevent revealing the pass
           word. Only a small number of password failures are permit
           ted before login exits and the communications link is sev
           ered.

           If password aging has been enabled for  the  account,  the
           user may be prompted for a new password before proceeding.
           He will be forced to provide his old password and the  new
           password  before continuing. Please refer to passwd(1) for
           more information.

           The user and group ID will be set according to their  val
           ues  in the file. There is one exception if the user ID is
           zero: in this case, only  the  primary  group  ID  of  the
           account  is  set.  This  should  prevent  that  the system
           adminitrator cannot login in  case  of  network  problems.
           The  value  for  $HOME, $SHELL, $PATH, $LOGNAME, and $MAIL
           are set according to the appropriate fields in  the  pass
           word        entry.         $PATH        defaults        to
           /usr/local/bin:/bin:/usr/bin:.  for normal users,  and  to
           /sbin:/bin:/usr/sbin:/usr/bin  for  root if not other con
           figured. Ulimit, umask and nice values  may  also  be  set
           according  to  entries in the GECOS field. The environment
           variable $TERM will be  preserved,  if  it  exists  (other
           environment  variables  are  preserved if the -p option is
           given) or be initialize to the terminal type on  your  tty
           line, as specified in /etc/ttytype.

           Then the user's shell is started. If no shell is specified
           for the user in /etc/passwd, then  /bin/sh  is  used.   If
           there  is no directory specified in /etc/passwd, then / is
           used (the home directory is  checked  for  the  .hushlogin
           file described above).

           This  login  implementation  does  ignore /etc/nologin and
           /etc/securetty.  You need to configure  this  in  the  PAM
           configuration file for login in /etc/pam.d/login.

           login  reads  the  /etc/login.defs(5)  configuration file.
           Please refer to this documenation for options which  could
           be set.

## SPECIAL ACCESS RESTRICTIONS

           The  file /etc/securetty lists the names of the ttys where
           root is allowed to log in. One name of a tty device  with
           out  the  /dev/ prefix must be specified on each line.  If
           the file does not exist, root is allowed to log in on  any
           tty.  You  need  to add the /lib/security/pam_securetty.so
           module in /etc/pam.d/login for activating.

## FILES

           /var/run/utmp - list of current login sessins
           /var/log/wtmp - list of previous login sessions
           /var/log/lastlog - list of times of previous user logins
           /etc/passwd - user account information
           /etc/shadow - encrypted passwords and age information
           /etc/motd - system message file
           /etc/ttytype - list of terminal types (/etc/login.defs)

## SEE ALSO

           init(8), getty(8), mail(1),  passwd(1),  passwd(5),  envi
           ron(7), shutdown(8), login.defs(5)

## BUGS

           A  recursive login, as used to be possible in the good old
           days, no longer works; for most purposes su(1) is a satis
           factory  substitute.  Indeed,  for security reasons, login
           does a vhangup() system call to remove any  possible  lis
           tening  processes  on  the  tty. This is to avoid password
           sniffing. If one uses the command "login", then  the  sur
           rounding  shell  gets  killed by vhangup() because it's no
           longer the true owner of the tty.  This can be avoided  by
           using "exec login" in a top-level shell or xterm.

## AUTHOR

           Derived  from  BSD  login  5.40  (5/9/89)  by Michael Glad
           (glad@daimi.dk) for HP-UX
           Ported to Linux 0.12: Peter Orbaek (poe@daimi.aau.dk)
           Added new features: Thorsten Kukuk (kukuk@suse.de)

    PAM Login 3.8             15. July 2002                  LOGIN(1)