Copyright (c) 1980 Regents of the University of California.
All rights reserved. The Berkeley software License Agreement
specifies the terms and conditions for redistribution.

@(#)login.1 6.1 (Berkeley) 04/29/85

C 4 login - sign on login [ -p ] [ username ] The login command is used when a user initially signs on, or it may be used at any time to change from one user to another. The latter case is the one summarized above and described here. See \*(lqHow to Get Started\*(rq for how to dial up initially.

If login is invoked without an argument, it asks for a user name, and, if appropriate, a password. Echoing is turned off (if possible) during the typing of the password, so it will not appear on the written record of the session.

After a successful login, accounting files are updated and the user is informed of the existence of mail, and the message of the day is printed, as is the time he last logged in (unless he has a \*(lq.hushlogin\*(rq file in his home directory - this is mostly used to make life easier for non-human users, such as uucp ).

Login initializes the user and group IDs and the working directory, then executes a command interpreter (usually sh (1)) according to specifications found in a password file. Argument 0 of the command interpreter is \*(lq-sh\*(rq, or more generally the name of the command interpreter with a leading dash (\*(lq-\*(rq) prepended.

Login also modifies the environment environ (7) with information specifying home directory, command interpreter, terminal type (if available) and user name. The `-p' argument causes the environment to be preserved from getty.

If the file /etc/nologin exists login prints its contents on the user's terminal and exits. This is used by shutdown (8) to stop users logging in when the system is about to go down.

Login is recognized by sh (1) and csh (1) and executed directly (without forking).

/etc/utmp accounting

/usr/adm/wtmp accounting

/usr/spool/mail/* mail

/etc/motd message-of-the-day

/etc/passwd password file

/etc/nologin stops logins

.hushlogin makes login quieter

init(8), getty(8), mail(1), passwd(1), passwd(5), environ(7), shutdown(8) \*(lqLogin incorrect,\*(rq if the name or the password is bad.

\*(lqNo Shell\*(rq, \*(lqcannot open password file\*(rq, \*(lqno directory\*(rq: consult a programming counselor.

An undocumented option, -r is used by the remote login server, rlogind (8C) to force login to enter into an initial connection protocol.