login(1)login(1)Namelogin - log in to a system
Syntaxlogin [username]
Description
The 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. To sign on initially, see the
Guide to System Environment Setup.
If 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 does not appear on the written record
of the session.
After a successful login accounting files are updated, the user is
informed of the existence of mail, the message of the day is printed,
and the time of last successful login is displayed. The display of all
this information can be prevented by creating the file .hushlogin in
the accounts login directory. This is useful for accounts such as uucp.
If ULTRIX security features are enabled additional things may happen.
These include the display of the number of failed login attempts since
the last successful login and forcing the setting of a new password.
See the Security Guide for Users and Security Guide for Administrators
for more information.
The command initializes the user and group IDs, the working directory,
and the users audit information, then executes a command interpreter,
usually according to specifications found in a password file. Argument
0 of the command interpreter is “-sh”, or more generally the name of
the command interpreter with a leading dash (“-”) prepended.
The command also initializes the environment with information specify‐
ing home directory, command interpreter, terminal type (if available)
and user name.
When is used in conjunction with it is the responsibility of the getty
program to initialize the terminal attributes. Specifically if a ter‐
minal is setup to use 8-bit characters the program should use a entry
which specifies 8-bit characters. If a terminal is setup in 8-bit mode
but fails to specify an 8-bit gettytab entry, then characters output by
both and may appear as multinational characters.
If the file exists, prints its contents on the user's terminal and
exits. This is used by to stop users logging in when the system is
about to go down.
The command is recognized by and and executed directly (without fork‐
ing).
If a root login is attempted and an invalid command interpreter is
specified, the interpreter is used.
Options-r Used by the remote login server, to force to enter
into an initial connection protocol.
-P <programname> Causes to set it's standard input and output to be
connected to the prompting program <programname>.
-C string Allows the system to specify a command to be run
using the user's shell. This option causes a user
shell -c string to be
-e Forces to use an extended protocol when communicat‐
ing with a prompter program (see -P).
Restrictions
To provide flow control, CTRL/S and CTRL/Q are ignored and are there‐
fore invalid characters in a login name.
Diagnostics
Login incorrect
If the username and password are not a valid combination.
Too many users logged on already. Try again later.
The system has the maximum licensed number of users logged on already.
License not valid for this version of ULTRIX.
The PAK that has been registered is for an earlier version of ULTRIX.
No valid license found for ULTRIX.
There is either no ULTRIX PAK registered or the PAK that has been found
is not valid, possibly because it has terminated.
Requires secure terminal
An attempt was made to login as UID 0 on a line that is not marked as
secure in
No shell
The login shell specified for the account cannot be executed. Consult
the system administrator.
No directory! Logging in with home=/
The HOME directory for the account is inaccessible. This can happen if
the directory resides on an NFS file system served by a host that is
not currently available.
You have too many processes running
Completion of login would exceed the maximum number of running pro‐
cesses allowed for the user.
You have mail
You have a non-empty mail spool file.
If ULTRIX security features are enabled the following messages are also
possible from login:
Your password has expired
The password for your account has not been changed recently enough.
Consult your system administrator.
Your password has expired, please change it
Your password has expired recently. You have to change it before you
can proceed any further.
Your password will expire very soon
Your password will expire in less than 24 hours.
Your password will expire in %d days
The ``%d'' is replaced with the number of days until your password
expires. You should consider changing your password now.
This account is disabled
Consult your system administrator.
Kerberos initialization failure
Consult your system administrator.
Files
accounting
accounting
mail
message-of-the-day
authorization data base
password file
stops logins
sets I&A security level
makes login quieter
lists ttys that root may log in on
See Alsomail(1), passwd(1), yppasswd(1yp), passwd(5yp), environ(7), getty(8),
init(8), rlogind(8c), shutdown(8)
Guide to System Environment Setup
Security Guide for Users
Security Guide for Administrators
login(1)