LOGIN(1)                     General Commands Manual                    LOGIN(1)

     login – log into the computer

     login [-pq] [-h hostname] [user]
     login -f [-lpq] [-h hostname] [user [prog [args...]]]

     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
     configurable via pam(8).  Password authentication is the default.

     The following options are available:

     -f      When a user name is specified, this option indicates 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.

             With the -f option, an alternate program (and any arguments) may be
             run instead of the user's default shell.  The program and arguments
             follows the user name.

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

     -l      Tells the program executed by login that this is not a login
             session (by convention, a login session is signalled to the program
             with a hyphen as the first character of argv[0]; this option
             disables that), and prevents it from chdir(2)ing to the user's home
             directory.  The default is to add the hyphen (this is a login

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

     -q      This forces quiet logins, as if a .hushlogin is present.

     If the file /etc/nologin exists, login dislays 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.

     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.  -q is specified, all
     of these messages are suppressed.  This is to simplify logins for non-human
     users, such as uucp(1).  login then records an entry in utmpx(5) and the
     like, and executes the user's command interpreter (or the program specified
     on the command line if -f is specified).

     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

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

     The login utility will submit an audit record when login succeeds or fails.
     Failure to determine the current auditing state will result in an error
     exit from login.

     /etc/motd          message-of-the-day
     /etc/nologin       disallows logins
     /var/run/utmpx     current logins
     /var/mail/user     system mailboxes
     .hushlogin         makes login quieter
     /etc/pam.d/login   pam(8) configuration file
                        user flags for auditing
                        global flags for auditing

     builtin(1), chpass(1), newgrp(1), passwd(1), rlogin(1), getpass(3),
     utmpx(5), environ(7)

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

macOS 12.1                     September 13, 2006                     macOS 12.1