LOGIN(1)
NAME
login − sign on
USAGE
login [ name [ env-var ... ]]
DESCRIPTION
Login may be invoked by you as a command, or by the system when a connection is first established. If you invoke login as a command, it must replace the initial command interpreter. To do this, type
# exec login
or
# exec login name
at a shell prompt.
Login prompts for a name if none was supplied and, if appropriate, a password. The password is not echoed, so it will not appear on the transcript.
After a successful log-in, the message-of-the-day, if any, is printed and the user- and group-ID’s are initialized. The working directory and command interpreter (shell) are then set as specified in /etc/passwd. If no shell is specified in your password file entry, then the default command interpreter, /bin/sh, is used.
If you change the shell field in your /etc/passwd entry, you must also run /etc/crpasswd to update the file /etc/passwd.map. All other changes to /etc/passwd (i.e., of home directory or password) must be made through the Registry. Normally, access to /etc/passwd is restricted to root.
Login initializes the following environment variables:
HOME=your-login-directory
PATH=:/bin:/usr/bin
SHELL=last-field-of-passwd-entry
MAIL=/usr/mail/your-login-name
TZ=timezone-specification
The environment may be expanded or modified by supplying additional arguments to login, either at execution time or when your log-in name is requested. The arguments may take either the form xxx or xxx=yyy. Arguments without an equal sign are placed in the environment as the following, where n is a number starting at zero and is incremented each time a new variable name is required:
Ln=xxx
Variables containing an equal sign (=) are placed into the environment without modification. If they already appear in the environment, then they replace the older value. There are two exceptions. The variables PATH and SHELL cannot be changed. This prevents people, logging into restricted Shell environments, from spawning secondary Shells that are not restricted. Login understands simple single-character quoting conventions. Typing a backslash in front of a character quotes it and allows the inclusion of such things as spaces and tabs.
CAUTIONS
If you do not complete login successfully within a certain period of time (e.g., one minute), you may be silently disconnected.
FILES
/usr/spool/mail/your-namemailbox for user your-name
/etc/motdmessage-of-the-day
/etc/passwdpassword file
.profileBourne Shell command file
.loginC Shell command file
DIAGNOSTICS
“Login incorrect”: User name or the password cannot be matched.
“No shell,” “Cannot open password file,” or “no directory”: Consult system administrator.