.TH LOGIN 8
.CT 1 sa_auto
.SH NAME
login \- sign on
.SH SYNOPSIS
.B /etc/login
.I name
.br
.B /etc/login
.B -f
.I name
[
.I cmd
]
.br
.B /etc/login
.B -p
.I passwd-line
[
.I cmd
]
.SH DESCRIPTION
.I Login
is executed by
.IR getty (8).
See the Introduction to this volume for how to dial up initially.
.PP
.I Login
asks for a password if appropriate.
Echoing is turned off during the typing of the password.
The
.B -f
option forces login of the named user, without a password.
.B -p
is similar to
.BR -f ,
but an entire line of password file information
is supplied.
.PP
.I Login
initializes the userid, the groupid, and the working directory
according to specifications found in the password file;
see
.IR passwd (5).
It also initializes environment variables
.SM PATH
and
.SM HOME .
Finally it executes a command interpreter (usually
.IR  sh (1)).
Argument 0 of the command interpreter is its name with
a dash
.RL ( - )
prepended.
If
a
.I cmd
argument was present,
two additional arguments
.B -c
.I cmd
are passed,
and environment variable
.SM REXEC
is set to
.LR 1 .
.PP
Upon a successful login,
accounting files are updated and,
if no options are present,
the message of the day is printed
and the user is informed of the
existence of mail.
.PP
Successful logins are recorded in
.F /etc/utmp
and
.FR /usr/adm/wtmp .
If
.I cmd
was present,
.L *
is appended to the login name in
.IR wtmp ,
and
no record is made in
.IR utmp .
.PP
Only the super-user may execute
.IR login .
.SH FILES
.TF /usr/spool/mail/*
.TP
.F /etc/utmp
accounting
.TP
.F /usr/adm/wtmp
accounting
.TP
.F /usr/spool/mail/*
mail
.TP
.F /etc/motd
message-of-the-day
.TP
.F /etc/passwd
password file
.TP
.F /etc/group
groups file
.SH "SEE ALSO"
.IR newgrp (1),
.IR passwd (1),
.IR environ (5),
.IR passwd (5),
.IR getty (8),
.IR init (8),
.IR su (8),
.IR svcmgr (8).
.SH DIAGNOSTICS
`Login incorrect':
the name or the password is bad.
.br
`No Shell' or `no directory': the initial shell or
home directory specified in the password file does not exist.
.br
`Cannot open password file': things are badly curdled.
.SH BUGS
Information passed to options
.B -p
and
.B -f
is not checked.
Only trusted programs should run
.IR login .
Only trusted programs may usefully do so anyway;
.I login
has no privileges.