docs: Documentation directory added

Move readme, licence, change log, relese notes and other
supplementary files to a Documentation directory. This commit
does not change contents of any other but few Makefile.am files.

Signed-off-by: Sami Kerola <kerolasa@iki.fi>

1 files changed, 583 insertions, 0 deletions

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+README for init/getty/login, by poe@daimi.aau.dk
+
+This package contains simpleinit, agetty, and login programs for Linux.
+Additional utilities included are: hostname, who, write, wall, users
+domainname, hostid, cage and mesg.
+
+Most of this software has been contributed by others, I basically just
+ported the things to Linux.
+
+About installation: See the bottom of this file. Check the Makefile!
+Be sure you know what you are doing! You may well be able to lock
+yourself out from your machine. Especially: The init provided here
+(simpleinit) is NOT a SYSV compatible init and the inittab format
+is different.
+
+If you are uncertain whether you got the latest version, check out
+
+	ftp://ftp.daimi.aau.dk/pub/linux/poe/
+
+Version 1.49 (20-Jun-97)
+	Small patches for new util-linux distribution and glibc compat.
+	PAM support in login.c by Erik Troan.
+
+Version 1.48 (6-Jun-97)
+	Now changes mode and owner of /dev/vcs devices for console logins.
+	After idea by Andries Brouwer.
+
+Version 1.47 (2-Apr-97)
+	Got new version of hostid.c and hostid.1 from 
+	Sander van Malssen <svm@kozmix.ow.nl>.
+	Removed premature endutent() call in login.c, simpleinit.c and 
+	agetty.c to be compatible with the changed semantics of gnu libc2. 
+	Fix by Jesse Thilo <Jesse.Thilo@pobox.com>.
+
+Version 1.46 (28-Jan-97)
+	Several security fixes for login by David Holland (buffer overruns)
+	<dholland@hcs.harvard.edu>
+	Fixed write.c, to handle a terminating period correctly.
+	Re-indented login.c, it was getting too messy.
+
+Version 1.45a (16-Dec-96)
+	Better support in login for shadow passwords. Compile with
+	-DSHADOW_PWD if you have <shadow.h>. This is on by default.
+	By Marek Michalkiewicz <marekm@i17linuxb.ists.pwr.wroc.pl>.
+	Changed the wtmp locking scheme in login.c,agetty.c,simpleinit.c
+	to flock() /etc/wtmplock instead of the wtmp file directly.
+	This avoids a denial of service attack.
+	Some support for the RB-1 Cryptocard token for challenge/response
+	authentication. This needs a DES library, either Eric Young's
+	libdes, or the Koontz implementation, see cryptocard.c.
+	Initial support patch by Randolph Bentson, 
+	<bentson@grieg.seaslug.org>
+	Changed getpass() to use fputs() instead of fprintf().
+
+Version 1.44 (13-Nov-96):
+	Made isapty() in checktty.c more resilient to 2.0 systems
+	that haven't re-MAKEDEV'ed their pty devices.
+
+Version 1.43 (8-Nov-96):
+	Fix to checktty.c: PTY's are numbered differently after 1.3,
+	blush! Fix by Gerhard Schneider <gs@ilfb.tuwien.ac.at>
+
+Version 1.42c (6-Nov-96):
+	Small fix by Gabriel M. Schuyler <schuyler@easiest.com>, to get
+	better syslog messages (1 LOGIN FAILURE instead of 2 LOGIN FAILURES).
+	Patch butchered by me.
+
+Version 1.42b (30-Sep-96):
+	Got patch for checktty.c from Christoph Lameter
+	<clameter@miriam.fuller.edu> so it doesn't traverse the groupfile
+	"manually" but uses the getgroups() call, this is more efficient
+	with large groupfiles and NIS/YP.
+
+Version 1.42a (24-Sep-96):
+	Added extra syslog() call to login.c to log all good logins.
+	Patch from Steve Philp.
+
+Version 1.41 (20-Jul-96):
+	Added security fix to checktty.c by JDS to clear certain lists.
+	Patches butchered and ANSI'fied by me.
+	Added -n option to agetty to avoid the login prompt.
+
+Version 1.40a (29-Dec-95):
+	Added -f <issue_file> option to agetty. Patches from Eric Rasmussen
+	<ear@usfirst.org>, but somewhat butchered by me.
+
+Version 1.39 (25-Oct-95):
+	Lots of testing and bugfixes in agetty. Now the modem init stuff 
+	should finally work (for me). Also wrote modem.agetty as an example
+	on how to use agetty with a modem.
+	Agetty now also supports baud rates of 38400, 57600, 115200 and
+	230400 bps.
+
+Version 1.37 (15-Sep-95):
+	Added -I <initstring> and -w options to agetty.c for those that
+	use agetty with modems.
+
+Version 1.36 (25-Aug-95): 
+	Enhanced /etc/usertty features with group support. Moved this part
+	of login.c to checktty.c. One can now define classes of hosts and
+	ttys and do access checking based on unix-group membership. See
+	login.1. Also time ranges for logins can be specified, for example
+	writing the line
+
+	joe	[mon:tue:wed:thu:fri:8-16]@barracuda [mon:tue:wed:thu:fri:0-7:17-23]@joes.pc.at.home [sat:sun:0-23]@joes.pc.at.home
+
+	says that during working hours, Joe may rlogin from the host
+	barracuda, whereas outside working hours and in weekends Joe may
+	rlogin from his networked PC at home.
+
+	login.c: failures was not properly initialized, it now is. Also
+	made sure ALL failures are really logged to syslog.
+
+Version 1.35 (7-Aug-95):
+	login.c: Much improved features for the usertty file, allows
+	access control based on both hostnames/addresses and line. See the 
+	about.usertty file and the man-page.
+
+	Fixed agetty so it doesn't fiddle with the ut_id field in the
+	utmp record, this should prevent growing utmps on systems with
+	more than 10 login lines. Fix suggested and checked by Alan Wendt 
+	<alan@ezlink.com> in his agetty.1.9.1a.
+
+	Agetty now installs as agetty again, not as getty.
+	Updated man-page for login(1) to document /etc/usertty changes.
+
+	This has been tested on Linux 1.2.5 with GCC 2.5.8 and libc 4.5.26.
+
+Version 1.33a (20-Jun-95):
+	rchatfie@cavern.nmsu.edu ("rc.") suggested that I should remove
+	the #ifndef linux around the special logging of dial-up 
+	logins. This is now done, so each login via a serial port 
+	generates a separate DIALUP syslog entry.
+
+Version 1.33 (5-Jun-95):
+	Patch by Ron Sommeling <sommel@sci.kun.nl> and
+	jlaiho@ichaos.nullnet.fi (Juha Laiho) for agetty.c, used
+	to return a pointer to an automatic variable in get_logname().
+	Many patches from or via Rickard Faith <faith@cs.unc.edu>, fixing
+	man-pages etc, now defaults to using /var/log/wtmp and /var/run/utmp
+	according to the new FSSTND.
+
+	Fix in login.c for CPU eating bug when a remote telnet client dies
+	while logging in.
+
+	This is for Linux 1.2, GCC 2.6.2 or later.
+
+Version 1.32b (12-Mar-95):
+	Login now sets the tty group to "tty" instead of "other". Depending
+	on compile-time define USE_TTY_GROUP the tty mode is set to 0620 or
+	0600 instead of 0622. All as per suggestion by Rik Faith and the
+	linux-security list.
+	Write/wall now strips control chars except BEL (\007). Again after
+	suggestion by Rik Faith.
+
+Version 1.32a
+	Urgent security patch from Alvaro M. Echevarria incorporated into
+	login.c. This is really needed on machines running YP until
+	the libraries are fixed.
+
+Version 1.32
+	Login now logs the ip-address of the connecting host to utmp as it
+	should.
+
+Version 1.31b (2-Feb-95):
+	Daniel Quinlan <quinlan@yggdrasil.com> and Ross Biro 
+	<biro@yggdrasil.com> suggested a patch to login.c that allows for 
+	shell scripts in the shell field of /etc/passwd, so one can now
+	have (as a line in /etc/passwd):
+		bye::1000:1000:Outlogger:/bin:echo Bye
+	Logging in as "bye" with no password simply echoes Bye on the screen.
+	This has applications for pppd/slip.
+
+Version 1.31a (28-Oct-94):
+	Scott Telford provided a patch for simpleinit, so executing reboot
+	from singleuser mode won't partially execute /etc/rc before
+	the reboot.
+
+Version 1.30 (17-Sep-94):
+	tobias@server.et-inf.fho-emden.de (Peter Tobias) has made a more 
+	advanced hostname command that understands some options such as
+	-f for FQDN etc. I'll not duplicate his work. Use his hostname
+	package if you wish.
+
+	svm@kozmix.xs4all.nl (Sander van Malssen) provided more features
+	for the /etc/issue file in agetty. \U and \u now expand to the 
+	number of current users.
+
+	It is now possible to state the value of TERM on the agetty command
+	line. This was also provided by Sander.
+
+	This has been built under Linux 1.1.42 with gcc 2.5.8 and libc 4.5.26.
+
+Version 1.29 (18-Aug-94):
+	Finally got around to making a real version after the numerous
+	alpha versions of 1.28. Scott Telford <st@epcc.ed.ac.uk> provided
+	a patch for write(1) to make it look more like BSD write.
+
+	Fixed login so that the .hushlogin feature works even with real
+	protective users mounted via NFS (ie. where root can't access
+	the user's .hushlogin file).
+
+	Cleaned up the code to make -Wall bearable.
+
+Version 1.28c (21-Jul-94):
+	Rik Faith reminded me that agetty should use the syslog
+	facility. It now does.
+
+Version 1.28b (30-May-94):
+	On suggestion from Jeremy Fitzhardinge <jeremy@suite.sw.oz.au>
+	I added -- as option delimiter on args passed from agetty to
+	login. Fixes -froot hole for other login programs. The login
+	program in this package never had that hole.
+
+Version 1.28a (16-May-94):
+	bill@goshawk.lanl.gov provided a couple of patches, one fixing
+	terminal setup in agetty, and reboot is now supposed to be
+	in /sbin according to FSSTND.
+
+Version 1.27 (10-May-94):
+	Changed login.c, so all bad login attempts are logged, and added
+	usertty security feature. See about.usertty for an explanation.
+	There's no longer a limit of 20 chars in the TERM environment 
+	variable. Suggested by Nicolai Langfeldt <janl@math.uio.no>
+
+	Added #ifdef HAVE_QUOTA around quota checks. Enable them if
+	you have quota stuff in your libraries and kernel.
+	Also re-enabled set/getpriority() calls as we now have them,
+	and have had for a long time...
+
+	Now wtmp is locked and unlocked around writes to avoid mangling.
+	Due to Jaakko Hyv{tti <HYVATTI@cc.helsinki.fi>.
+
+	Wrt. agetty: A \o in /etc/issue now inserts the domainname, as 
+	set by domainname(1). Sander van Malssen provided this.
+	This is being used under Linux 1.1.9
+
+	Beefed up the agetty.8 man-page to describe the /etc/issue
+	options. Added man-pages for wall, cage, who.
+
+Version 1.26 alpha (25-Apr-94):
+	Added patch from Bill Reynolds <bill@goshawk.lanl.gov> to 
+	simpleinit, so it will drop into single user if /etc/rc
+	fails, eg. from fsck.
+
+Version 1.25 (9-Feb-94):
+	Agetty should now work with the Linux 0.99pl15a kernel.
+	ECHOCTL and ECHOPRT are no longer set in the termios struct.
+	Also made agetty accept both "tty baudrate" and "baudrate tty"
+	arguments.
+
+Version 1.24 (23-Jan-94): changes since 1.22
+	Christian von Roques <roques@juliet.ka.sub.org> provided a patch
+	that cleans up the handling of the -L option on agetty. 
+	Rik Faith <faith@cs.unc.edu> enhanced several man-pages...
+
+Version 1.23 (11-Dec-93): changes since 1.21
+	Mitchum DSouza provided the hostid(1) code. It needs libc 4.4.4 or
+	later and a Linux 0.99.14 kernel or later. It can set and print
+	the world unique hostid of the machine. This may be used in 
+	connection with commercial software licenses. God forbid!
+	I added the -v option, and munged the code a bit, so don't blame
+	Mitch if you don't like it.
+
+	I made the "cage" program. Using this as a shell in the passwd
+	file, enables one to let users log into a chroot'ed environment.
+	For those that have modem logins and are concerned about security.
+	Read the source for further info.
+
+	"who am i" now works.
+
+	The login program works with Yellow Pages (aka NIS) simply by
+	linking with an appropriate library containing a proper version
+	of getpwnam() and friends.
+
+Version 1.21 (30-Oct-93): changes since 1.20
+	In simpleinit.c: The boottime wtmp record is now written *after*
+	/etc/rc is run, to put a correct timestamp on it.
+	Daniel Thumim <dthumim@mit.edu> suggested this fix.
+
+	The source and Makefile is prepared for optional installation of 
+	binaries in /sbin instead of /etc, and logfiles in /usr/adm instead
+	of /etc. See and change the Makefile to suit your preferences.
+	Rik Faith and Stephen Tweedie inspired this change.
+
+Version 1.20 (30-Jul-93): changes since 1.17:
+	Versions 1.18 and 1.19 were never made publically available.
+	Agetty now supports a -L switch that makes it force the CLOCAL flag.
+	This is useful if you have a local terminal attached with a partly
+	wired serial cable that does not pass on the Carrier Detect signal.
+
+	There's a domainname program like the hostname program; contributed
+	by Lars Wirzenius.
+
+	Simpleinit will now write a REBOOT record to wtmp on boot up. Time-
+	zone support is now optional in simpleinit. Both of these patches
+	were made by Scott Telford <st@epcc.ed.ac.uk>.
+
+	This is for Linux 0.99.11 or later.
+
+Version 1.17 (19-May-93): changes since 1.16:
+	Login, simpleinit and write should now work with shadow passwords
+	too. See the Makefile. Thanks to Anders Buch who let me have an
+	account on his SLS based Linux box on the Internet, so I could test
+	this. I should also thank jmorriso@rflab.ee.ubc.ca (John Paul Morrison)
+	who sent me the shadow patch to login.c
+
+Version 1.16 (24-Apr-93): changes since 1.15a:
+	Simpleinit now clears the utmp entry associated with the pid's that
+	it reaps if there is one. A few are still using simpleinit and this
+	was a popular demand. It also appends an entry to wtmp
+
+Version 1.15a (15-Mar-93): changes since 1.13a:
+	junio@shadow.twinsun.com (Jun Hamano) sent me a one-line fix
+	for occasional mangled issue-output from agetty.
+
+Version 1.13a (2-Mar-93): changes since 1.12a:
+	With the new LILO (0.9), there are more than one possible arg
+	to init, so Werner Almesberger <almesber@bernina.ethz.ch>
+	suggested that a loop over argv[] was made in boot_single() in
+	simpleinit.c
+
+Version 1.12a (24-Feb-93): changes since 1.11:
+	This is for Linux 0.99.6 or later. Built with gcc 2.3.3 and libc4.2
+	jrs@world.std.com (Rick Sladkey) told me that the setenv("TZ",..)
+	in login.c did more harm than good, so I commented it out.
+
+Version 1.11a (16-Feb-93): changes since 1.9a:
+	This is for Linux 0.99.5 or later.
+	Anthony Rumble <arumble@extro.ucc.su.OZ.AU> made me avare that
+	the patches for vhangup() from Steven S. Dick didn't quite work,
+	so I changed it.
+
+	Linus Torvalds provided another patch relating to vhangup, since
+	in newer Linuxen vhangup() doesn't really close all files, so we
+	can't just open the tty's again.
+
+Version 1.9a (18-Jan-93): changes since 1.8a:
+	Rick Faith sent me man-pages for most of the untilities in this
+	package. They are now included.
+
+	Steven S. Dick <ssd@nevets.oau.org> sent me a patch for login.c
+	so DTR won't drop during vhangup() on a modemline.
+
+	This is completely untested!! I haven't even had the time to
+	compile it yet.
+
+Version 1.8a (13-Dec-92): changes since 1.7:
+	This is for Linux 0.98.6 or later. Compiles with gcc2.2.2d7 and libc4.1
+
+	Bettered write/wall after fix from I forget who. Now wall can have
+	commandline args.
+
+	Fixed bug in who.c
+
+	Patched simpleinit.c with patch from Ed Carp, so it sets the timezone
+	from /etc/TZ. Should probably by be /etc/timezone.
+
+	Sander Van Malssen <sander@kozmix.hacktic.nl> provided a patch
+	for getty, so it can understand certain escapecodes in /etc/issue.
+
+	I hacked up a very simple substitute for a syslog() call, to try out
+	the logging. If you have a real syslog() and syslogd then use that!
+
+	The special vhangup.c file is out, it's in the official libc by now.
+	(and even in the libc that I have :-)
+
+	who, and write are now deprecated, get the better ones from one of
+	the GNU packages, shellutils I think.
+
+	Some people think that the simple init provided in this package is too
+	spartan, if you think the same, then get the SYSV compatible init
+	from Miquel van Smoorenburg <miquels@maestro.htsa.aha.nl>
+	Simpleinit will probably be deprecated in the future.
+
+Version 1.7: 26-Oct-92 changes since 1.6:
+	This is for Linux 0.97PL4 or later.
+
+	Thanks to Werner Almesberger, init now has support for a 
+	singleuser mode. 
+
+	Login now supports the -h <hostname> option, used in connection
+	with TCP/IP. (rlogin/telnet)
+
+	Getty writes an entry to /etc/wtmp when started, so last won't report
+	"still logged in" for tty's that have not been logged into since
+	the last user of that tty logged out. This patch was inspired by
+	Mitchum DSouza. To gain the full benefit of this, get the newest
+	last from the admutils-1.4.tar.Z package or later.
+
+Version 1.6 (29-Aug-92): changes since 1.5:
+	This is for Linux 0.97P1+ or later.
+	
+	Login now uses the newly implemented vhangup() sys-call, to prevent
+	snooping on the tty.
+	An alternative getpass() function is now provided with login, because
+	I was told that the old one in libc didn't work with telnet and
+	or rlogin. I don't have a network or a kernel with TCP/IP so I haven't
+	tested the new one with telnet, but it is derived from BSD sources
+	that are supposed to work with networking.
+
+Version 1.5 (12-Aug-92): changes since 1.4
+	This is for Linux 0.97 or later, and has been built with gcc2.2.2
+
+	This release just puts in a few bugfixes in login.c and simpleinit.c
+
+Version 1.4 (4-Jul-92): changes since 1.3:
+	This is for Linux 0.96b, and has been built and tested with gcc 2.2.2.
+
+	Init now handles the SIGINT signal. When init gets a SIGINT it will
+	call /usr/bin/reboot and thereby gently reboot the machine. This
+	makes sense because after Linux 0.96B-PL1 the key-combination
+	Ctrl-Alt-Del may send a SIGINT to init instead of booting the 
+	machine the hard way without syncing or anything.
+
+	You may want to get the admutils-1.1 package which includes a program
+	that will instruct the kernel to use the "gentle-reboot" procedure.
+
+Version 1.3 (14-Jun-92): changes since 1.2:
+	This is for Linux 0.96A.
+
+	The ioctl(TIOCSWINSZ) has been removed from login.c because it now
+	works :-).
+	
+	login.c now supports a lastlog database.
+
+	Several programs and pieces of source that were included in the 1.2
+	package has been *removed* as they are incorporated into the new
+	libc. Other omitted parts such as last(1) has been replaced by
+	better versions, and can be found in the admutils package.
+
+	Agetty is now called getty and will be placed in /etc.
+
+	A few changes has been made to make it possible to compile the
+	stuff with GCC 2.x.
+
+Version 1.2 (28-Feb-92): changes since 1.1:
+	This is for Linux 0.12.
+
+	A couple of problems with simpleinit.c has been solved, thanks to
+	Humberto Zuazaga. So now init groks comments in /etc/inittab, and
+	handles the HUP and TSTP signals properly.
+
+	I added two small scripts to the distribution: users and mesg.
+
+	TERM is now carried through from /etc/inittab all the way to the
+	shell. Console tty's are special-cased, so the termcap entry in
+	/etc/inittab is overridden by the setting given at boot-time.
+	This requires a different patch to the kernel than that distributed
+	with version 1.1
+
+	Login no more sends superfluous chars from a password to the 
+	shell. It also properly prints a NL after the password.
+
+	Agetty didn't set the erase character properly, it does now.
+
+	A few extra defines has been added to utmp.h
+
+	Several netters helped discover the bugs in 1.1. Thanks to them
+	all.
+
+Version 1.1 (released 19-Feb-92): Changes since 1.0:
+	A bug in simpleinit.c has been fixed, thanks to Pietro Castelli.
+	The definition of the ut_line field has been changed to track the
+	USG standard more closely, we now strip "/dev/" off the front.
+	Thanks to: Douglas E. Quale and Stephen Gallimore.
+
+	I have added a getlogin.c library routine, and a write(1) command.
+	I removed the qpl-init stuff. If people want to use it, they should
+	get it from the source. I don't want to hack on it anymore.
+
+	A couple of people reported problems with getty having problems 
+	with serial terminals. That was correct. I borrowed a null-modem
+	from Tommy Thorn, and now the problems should be fixed. It seems
+	that there is kept a lot of garbage in the serial buffers, flush
+	them and it works like a charm. Getty does an ioctl(0, TCFLSH, 2)
+	for this.
+
+	The write.c code now doubles as code for a wall(1) program.
+
+Description of the various files:
+
+login.c		The login program. This is a portation of BSD login, first
+		to HP-UX 8.0 by Michael Glad (glad@daimi.aau.dk), and
+		to Linux (initially to 0.12) by me.
+
+who.c		A simple who(1) util. to list utmp. Done by me.
+		You may prefer the GNU who util. with more options
+		and features.
+
+hostname.c	A hostname(1) command to get and set the hostname. I did
+		this too.
+
+domainname.c	Like hostname, only reads out or sets the domainname.
+
+agetty.c	The getty program. From comp.sources.misc, by W.Z. Venema.
+		Hacked a bit by me.
+
+simpleinit.c	A simple init program, written by me. Uses /etc/inittab
+
+		A "kill -HUP" to init makes it re-read /etc/inittab.
+		A "kill -TSTP" to init makes it stop spawning gettys on the
+		ttys. A second "kill -TSTP" starts it again.
+		A kill -INT to init makes it attempt a reboot of the machine.
+		this works in connection with kernel support for softboot
+		when Ctrl-Alt-Del is pressed.
+
+		Init will start up in singleuser mode if /etc/singleboot
+		exists at boottime, or if it is given an argument of "single"
+		via eg. LILO. If /etc/securesingle exists it will ask for the
+		root password before starting single user.
+
+write.c		A write(1) command, used to pass messages between users
+		at different terminals. This code doubles as code for 
+		a wall(1) command. Make a symlink: /usr/bin/wall ->
+		/usr/bin/write for this.
+
+mesg		A tiny shellscript, so you can avoid that other people write
+		to your shell.
+
+users		Another script that uses awk(1) and tr(1) to process the
+		output from who(1) into a one-liner.
+		If you don't have awk, but have Perl, this does the same:
+
+		who | perl -ane 'print "$F[0] "'; echo ""
+
+pathnames.h:
+		Header.
+
+param.h
+		Header, extended with getdtablesize() macro, should go
+		in /usr/include/sys
+
+Building.
+---------
+A "make all" should do. At least it does for me.
+
+Installation:
+-------------
+
+login		should go in /bin, if you don't like this change
+		pathnames.h and recompile at least agetty.
+
+getty, init	Put them in SBINDIR
+
+who, hostname, write, wall, mesg, users:
+		/usr/bin
+
+securetty	login needs this in /etc, defines which ttys that root
+		can login on. This should *never* include ttys{1,2}
+
+inittab		the simpleinit code needs this in /etc. Note that the syntax
+		of /etc/inittab has little to do with the syntax of a real
+		SysV inittab. Edit this one for your local setup.
+
+shells		The chsh program will use this if it's placed in /etc. It
+		defines the valid shell-programs. Have one abs. path on
+		each line.
+
+You can also do a "make install" as root, but don't just do it because I
+say so, check the Makefile first.
+
+"Make install" will install only the new binaries, and not motd, inittab,
+securetty and issue. To install these configuration files, do a 
+"make Install".
+
+Getty requires a /dev/console to write errors to. I just made it a symlink
+to /dev/tty1. Because of a bug in the tty driver this errorlogging may
+cause the shell on tty1 to logout.
+
+Getty will print the contents of /etc/issue if it's present before asking
+for username. Login will print the contents of /etc/motd after successful
+login. Login doesn't print /etc/motd, and doesn't check for mail if
+~/.hushlogin is present and world readable.
+
+If /etc/nologin is present then login will print its contents and disallow
+any logins except root.
+It might be a good idea to have a "rm -f /etc/nologin" line in one's 
+/etc/rc file.
+
+If /etc/securetty is present it defines which tty's that root can login on.
+
+   - Peter (poe@daimi.aau.dk)