NAME

login - sign on (includes AFS extensions)

SYNOPSIS

login [ username ]

DESCRIPTION

Login signs username on to the system initially; login may also be used at any time to change from one user i.d. to another. 

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

If the system is running an Andrew File System client process Login attempts to validate the user’s password with the Andrew file system file servers.  If successful, login informs the local Andrew Cache Manager process of the password so that it can make file server requests on the user’s behalf.  If the password typed does not match the password in the Andrew file system but does match the password in /etc/passwd, then login will allow a “local login.”  The user can use the machine, but will only have anonymous user access to remote files.  For security reasons, the user “root” always gets a local login. 

After a successful login, accounting files are updated and the user is informed of the existence of mail.  In addition, the message of the day and the time the user last logged in are printed (unless he or she has a .hushlogin file in his home directory.  This is mainly 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 csh(1)) according to specifications found in a password file.  Argument 0 of the command interpreter is “-csh”, or more generally the name of the command interpreter with a leading dash (“-”) prepended.

Login also initializes the environment environ(5) with information specifying home directory, command interpreter, terminal type (if available) and user name.

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 logins when the system is about to go down.

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

FILES

/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

/etc/ttys tty database

SEE ALSO

log(1V), init(8), getty(8), mail(1), passwd(1V), passwd(5), environ(5), shutdown(8)

DIAGNOSTICS

“Login incorrect":  the name or the password is bad (or mis-typed). 

“No Shell,” “cannot open password file,” “no directory”: consult a system administrator. 

“Couldn’t tell Venus password...": login could not find the local Andrew Cache Manager process.  The user will have anonymous access to that file system.  This page intentionally left blank. 

PRPQs 5799-WZQ/5799-PFF: IBM/4.3  —  Sept 1988