TTYACTION(5) BSD File Formats Manual TTYACTION(5)NAME
ttyaction -- ttyaction file format
DESCRIPTION
The ttyaction file specifies site-specific commands to run when a login session begins and ends. The ttyaction file contains a list of new-
line separated records, where each record has the following three fields:
ttyname Name of the tty line(s) on which this line should apply. The name is relative to the /dev directory, similar to how such devices
are named in the /etc/ttys file.
action Name of the action for which this line should apply. The action names currently defined are "login", "getty", "telnetd" and
"rlogind" which indicate which program is processing this file. (Note that "login" begins a login session, while the other three
are run after a login session ends.)
command What command to run if this record matches.
The first two fields are delimited with blanks or tabs, and the command field is all text to the end of the line. Either or both of first
two fields may contain wildcard match patterns as implemented by the fnmatch() library function.
All command strings are executed by passing them to /bin/sh -c running as "root," with an environment containing:
TTY=ttyname
ACT=action
USER=username
PATH=_PATH_STDPATH
These variables may be used directly in the shell command part of the record for simple tasks such as changing the ownership of related
devices. For example:
console * chown ${USER}:tty /dev/mouse
will chown the mouse appropriately when the console owner changes.
EXAMPLES
Here are some more example records:
tty0 login /somewhere/tty_setup ${TTY}
tty0 getty /somewhere/tty_clean ${TTY}
* * /somewhere/ttyfrob ${TTY} ${ACT}
SEE ALSO fnmatch(3), ttyaction(3)HISTORY
The ideas for the /etc/ttyaction file were inspired by the /etc/fbtab file under SunOS.
BSD August 24, 1996 BSD
Check Out this Related Man Page
LOGIN(1) BSD General Commands Manual LOGIN(1)NAME
login -- authenticate users and set up their session environment
SYNOPSIS
login [-Ffps] [-a address] [-h hostname] [user]
DESCRIPTION
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 done via passwords. If the user can be authenticated via S/Key, then the S/Key challenge is incorporated in the password prompt.
The user then has the option of entering their Kerberos or normal password or the S/Key response. Neither will be echoed.
The options are as follows:
-a The -a option specifies the address of 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.
-F The -F option acts like the -f option, but also indicates to login that it should attempt to rewrite an existing Kerberos 5 creden-
tials cache (specified by the KRB5CCNAME environment variable) after dropping permissions to the user logging in. This flag is not
supported under pam(8).
-f The -f option is used when a user name is specified to indicate 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.
-h The -h option specifies 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.
-p By default, login discards any previous environment. The -p option disables this behavior.
-s Require a secure authentication mechanism like Kerberos or S/Key to be used. This flag is not supported under pam(8).
If a user other than the superuser attempts to login while the file /etc/nologin exists, login displays its contents to the user and exits.
This is used by shutdown(8) to prevent normal 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.
This is to simplify logins for non-human users. login then records an entry in the wtmp(5) and utmp(5) files, executes site-specific login
commands via the ttyaction(3) facility with an action of "login", and executes the user's command interpreter.
login 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).
The user's login experience can be customized using login class capabilities as configured in /etc/login.conf and documented in
login.conf(5).
The standard shells, csh(1) and sh(1), do not fork before executing the login utility.
FILES
/etc/login.conf login class capability database
/etc/motd message-of-the-day
/etc/nologin disallows non-superuser logins
/var/run/utmp list of current logins
/var/log/lastlog last login account records
/var/log/wtmp login account records
/var/mail/user system mailboxes
.hushlogin makes login quieter
SEE ALSO chpass(1), newgrp(1), passwd(1), rlogin(1), skey(1), getpass(3), ttyaction(3), login.conf(5), passwd.conf(5), utmp(5), environ(7),
kerberos(8), pam(8)HISTORY
A login appeared in Version 6 AT&T UNIX.
TRADEMARKS AND PATENTS
S/Key is a trademark of Bellcore.
BSD November 19, 2008 BSD