BSD 4_4 release

[unix-history] / usr / src / usr.bin / login / login.1

diff --git a/usr/src/usr.bin/login/login.1 b/usr/src/usr.bin/login/login.1
index 774c1ad..db59c1a 100644 (file)
--- a/usr/src/usr.bin/login/login.1
+++ b/usr/src/usr.bin/login/login.1
@@ -1,174 +1,146 @@
-.\" Copyright (c) 1980, 1990 The Regents of the University of California.
-.\" All rights reserved.
+.\" Copyright (c) 1980, 1990, 1993
+.\"    The Regents of the University of California.  All rights reserved.

 .\"
 .\"

-.\" %sccs.include.redist.roff%
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 3. All advertising materials mentioning features or use of this software
+.\"    must display the following acknowledgement:
+.\"    This product includes software developed by the University of
+.\"    California, Berkeley and its contributors.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.

 .\"
 .\"

-.\"    @(#)login.1     6.11 (Berkeley) %G%
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.

 .\"
 .\"

-.Dd 
+.\"    @(#)login.1     8.1 (Berkeley) 6/9/93
+.\"
+.Dd June 9, 1993

 .Dt LOGIN 1
 .Os BSD 4
 .Sh NAME
 .Nm login
 .Dt LOGIN 1
 .Os BSD 4
 .Sh NAME
 .Nm login

-.Nd log on to a system
+.Nd log into the computer

 .Sh SYNOPSIS
 .Nm login
 .Sh SYNOPSIS
 .Nm login

-.Op Fl p
-.Op Ar user
-.Nm login
-.Op Fl p
+.Op Fl fp

 .Op Fl h Ar hostname
 .Op Fl h Ar hostname

-.Op Fl f

 .Op Ar user
 .Sh DESCRIPTION
 The
 .Nm login
 .Op Ar user
 .Sh DESCRIPTION
 The
 .Nm login

-command
-logs the given user
-.Ar user
-onto a
-.Tn UNIX
-system.
-It has three different uses;
-logging a user on to a system,
-re-logging a user in as another
-user (without logging out),
-and logging non-human users (programs)
-onto other systems.
-In the first two instances, the
+utility logs users (and pseudo-users) into the computer system.
+.Pp
+If no user is specified, or if a user is specified and authentication
+of the user fails,

 .Nm login
 .Nm login

-program protects the user's password
-from prying eyes by disabling the
-echoing of typed characters from terminals.
+prompts for a user name.
+Authentication of users is done via passwords.

 .Pp
 .Pp

-Options available:
-.Bl -tag -width xxxxhostname
+The options are as follows:
+.Bl -tag -width Ds

 .It Fl f
 The
 .Fl f
 .It Fl f
 The
 .Fl f

-option is used with
-a username on the command line, at initial login,
-to indicate that proper authentication has already been done
-and that no password need be requested.
-This option may be used by the superuser
-or by the user specified on the command line.
-.It Fl h Ar hostname
+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.
+.It Fl h

 The
 .Fl h
 The
 .Fl h

-option is used by
-.Xr telnetd  8
-(at initial login)
-and other servers to list the host from which
-the connection was received.
+option specifies the host from which the connection was received.
+It is used by various daemons such as
+.Xr telnetd  8 .
+This option may only be used by the super-user.

 .It Fl p
 .It Fl p

-Causes the remainder of the environment to be preserved,
-otherwise any previous environment is discarded.
-.El
-.Pp
-In the first usage of
+By default,

 .Nm login
 .Nm login

-it is invoked by the
-.Xr getty 8
-program which is responsible for initializing communications between
-a users terminal and
-.Tn UNIX .
-.Nm Login
-starts up
-by prompting for a user name; when it recives a valid user name and password
-the user is logged in and may proceed to work on the system.
+discards any previous environment.
+The
+.Fl p
+option disables this behavior.
+.El

 .Pp
 .Pp

-The second usage of
-.Nm login
-allows a user to log in as another user
-without having logout.
-In this case
+If the file
+.Pa /etc/nologin
+exists,

 .Nm login
 .Nm login

-is invoked from
-.Xr sh 1
-or
-.Xr csh 1
-as shown above in the first synopsis.
-.Pp
-The third usage is by system programs and servers like
-.Xr telnetd
-and may only be initiated by the super-user.
+dislays its contents to the user and exits.
+This is used by
+.Xr shutdown  8
+to prevent users from logging in when the system is about to go down.

 .Pp
 Immediately after logging a user in,
 .Nm login
 .Pp
 Immediately after logging a user in,
 .Nm login

-writes the date and time the user last logged in,
-the message of the day and notifies the user
-if he/she has new mail.
+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
 .Dq Pa .hushlogin
 If the file
 .Dq Pa .hushlogin

-exists in the user's home directory,
-both the message of the day and mail notification are
-suppressed; this
-is usually used to simplify the logins for non-human users, such as
+exists in the user's home directory, all of these messages are suppressed.
+This is to simplify logins for non-human users, such as

 .Xr uucp 1 .
 .Xr uucp 1 .

-.Nm login
+.Nm Login

 then records an entry in the
 .Xr wtmp 5
 and
 .Xr utmp 5
 then records an entry in the
 .Xr wtmp 5
 and
 .Xr utmp 5

-files and provides the user
-with the command shell found in the user's
-.Xr passwd 5
-entry.
+files and executes the user's command interpretor.

 .Pp
 .Pp

-Login also modifies the
-environment (see
+Login enters information into the environment (see

 .Xr environ 7 )
 .Xr environ 7 )

-with information specifying home directory, command interpreter, terminal
-type (if available) and user name.
-.Pp
-If the file
-.Pa /etc/nologin
-exists,
-.Nm login
-prints its contents on the user's terminal and exits. This is
-used by
-.Xr shutdown  8
-to prevent users from logging in when the system is about to go down.
+specifying the user's home directory (HOME), command interpreter (SHELL),
+search path (PATH), terminal type (TERM) and user name (both LOGNAME and
+USER).

 .Pp
 The standard shells,
 .Xr csh 1
 and
 .Pp
 The standard shells,
 .Xr csh 1
 and

-.Xr sh 1
-notice when login is invoked on a command line and execute
-it immediately with out calling
-.Xr fork 2 .
+.Xr sh 1 ,
+do not fork before executing the
+.Nm login
+utility.

 .Sh FILES
 .Sh FILES

-.Bl -tag -width /var/log/wtmp -compact
-.It Pa /var/run/utmp
-current logins
-.It Pa /var/log/wtmp
-login account records
-.It Pa /var/mail/*
-undelivered mail
+.Bl -tag -width /var/mail/userXXX -compact

 .It Pa /etc/motd
 message-of-the-day
 .It Pa /etc/motd
 message-of-the-day

-.It Pa /etc/passwd.*
-password files

 .It Pa /etc/nologin
 disallows logins
 .It Pa /etc/nologin
 disallows logins

+.It Pa /var/run/utmp
+current logins
+.It Pa /var/log/wtmp
+login account records
+.It Pa /var/mail/user
+system mailboxes

 .It Pa \&.hushlogin
 makes login quieter
 .El
 .Sh SEE ALSO
 .It Pa \&.hushlogin
 makes login quieter
 .El
 .Sh SEE ALSO

-.Xr mail 1 ,
+.Xr chpass 1 ,

 .Xr passwd 1 ,
 .Xr rlogin 1 ,
 .Xr getpass 3 ,
 .Xr passwd 1 ,
 .Xr rlogin 1 ,
 .Xr getpass 3 ,

-.Xr passwd 5 ,

 .Xr utmp 5 ,
 .Xr environ 7 ,
 .Xr utmp 5 ,
 .Xr environ 7 ,

-.Xr init 8 ,
-.Xr getty 8 ,
-.Xr shutdown 8 ,

 .Sh HISTORY
 A
 .Nm login
 appeared in
 .At v6 .
 .Sh HISTORY
 A
 .Nm login
 appeared in
 .At v6 .

-.Sh DIAGNOSTICS
-Self explanatory.