login(1)              UNIX System V(Essential Utilities)               login(1)


NAME
      login - sign on

SYNOPSIS
      login [ name [ environ ... ]]

DESCRIPTION
      The login command is used at the beginning of each terminal session and
      allows you to identify yourself to the system.  It may be invoked as a
      command or by the system when a connection is first established.  It is
      invoked by the system when a previous user has terminated the initial
      shell by typing a cntrl-d to indicate an end-of-file.

      If login is invoked as a command it must replace the initial command
      interpreter.  This is accomplished by typing
           exec login
      from the initial shell.

      login asks for your user name (if it is not supplied as an argument), and
      if appropriate, your password.  Echoing is turned off (where possible)
      during the typing of your password, so it will not appear on the written
      record of the session.

      If there are no lower-case characters in the first line of input
      processed, login assumes the connecting TTY is an upper-case-only
      terminal and sets the port's termio(7) options to reflect this.

      login accepts a device option, device.  device is taken to be the path
      name of the TTY port login is to operate on.  The use of the device
      option can be expected to improve login performance, since login will not
      need to call ttyname(3).

      If you make any mistake in the login procedure, the message
           Login incorrect
      is printed and a new login prompt will appear.  If you make five
      incorrect login attempts, all five may be logged in /var/adm/loginlog (if
      it exists) and the TTY line will be dropped.

      If you do not complete the login successfully within a certain period of
      time (e.g., one minute), you are likely to be silently disconnected.

      After a successful login, accounting files are updated, the /etc/profile
      script is executed, the time you last logged in is printed, /etc/motd is
      printed, the user-ID, group-ID, supplementary group list, working
      directory, and command interpreter (usually sh) are initialized, and the
      file .profile in the working directory is executed, if it exists.  The
      name of the command interpreter is - followed by the last component of
      the interpreter's path name (e.g., -sh).  If this field in the password
      file is empty, then the default command interpreter, /usr/bin/sh is used.
      If this field is *, then the named directory becomes the root directory,
      the starting point for path searches for path names beginning with a /.
      At that point login is re-executed at the new level which must have its


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login(1)              UNIX System V(Essential Utilities)               login(1)


      own root structure, including /var/adm/login and /etc/passwd.

      The basic environment is initialized to:

            HOME=your-login-directory
            LOGNAME=your-login-name
            PATH=/usr/bin
            SHELL=last-field-of-passwd-entry
            MAIL=/var/mail/your-login-name
            TZ=timezone-specification

      The environment may be expanded or modified by supplying additional
      arguments to login, either at execution time or when login requests your
      login name.  The arguments may take either the form xxx or xxx=yyy.
      Arguments without an equal sign are placed in the environment as
           Ln=xxx
      where n is a number starting at 0 and is incremented each time a new
      variable name is required.  Variables containing an = are placed in the
      environment without modification.  If they already appear in the
      environment, then they replace the older value.  There are two
      exceptions.  The variables PATH and SHELL cannot be changed.  This
      prevents people, logging into restricted shell environments, from
      spawning secondary shells which are not restricted. login understands
      simple single-character quoting conventions.  Typing a backslash in front
      of a character quotes it and allows the inclusion of such characters as
      spaces and tabs.

FILES
      /var/adm/utmp        accounting
      /var/adm/wtmp        accounting
      /var/mail/your-name  mailbox for user your-name
      /var/adm/loginlog    record of failed login attempts
      /etc/motd            message-of-the-day
      /etc/passwd          password file
      /etc/profile         system profile
      .profile             user's login profile
      /var/adm/lastlog     time of last login

SEE ALSO
      mail(1), newgrp(1M), sh(1), su(1M).
      loginlog(4), passwd(4), profile(4), environ(5) in the  Programmer's
      Reference Manual.

DIAGNOSTICS
      login incorrect if the user name or the password cannot be matched.
      No shell, cannot open password file, or no directory:  consult a system
      engineer.
      No utmp entry. You must exec "login" from the lowest level "sh" if you
      attempted to execute login as a command without using the shell's exec
      internal command or from a shell other than the initial shell.




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