LOGIN(1) | General Commands Manual | LOGIN(1) |
login
— log into
the computer
login |
[-fpq ] [-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
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
-l
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
session).-p
login
discards any previous
environment. The -p
option disables this
behavior.-q
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. If -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 USER).
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
.
builtin(1), chpass(1), csh(1), newgrp(1), passwd(1), rlogin(1), getpass(3), utmpx(5), environ(7)
A login
utility appeared in
Version 6 AT&T UNIX.
September 13, 2006 | Mac OS X 12 |