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GETTY(1M)							     GETTY(1M)

NAME    [Toc]    [Back]

     getty - set terminal type,	modes, speed, and line discipline

SYNOPSIS    [Toc]    [Back]

     /sbin/getty [-hN] [-t timeout] line [speed	[type [linedisc]]]
     /sbin/getty -c file

DESCRIPTION    [Toc]    [Back]

     getty is a	program	that is	invoked	by init(1M).  It is the	second process
     in	the series, (init-getty-login-shell) that ultimately connects a	user
     with the UNIX system.  It can only	be executed by the super-user; that
     is, a process with	the user-ID of root.  Initially	getty prints the
     contents of /etc/issue (if	it exists), then prints	the login message
     field for the entry it is using from /etc/gettydefs, reads	the user's
     login name, and invokes the login(1) command with the user's name as
     argument.	While reading the name,	getty attempts to adapt	the system to
     the speed and type	of terminal being used.	 It does this by using the
     options and arguments specified.

     Line is the name of a tty line in /dev to which getty is to attach
     itself.  getty uses this string as	the name of a file in the /dev
     directory to open for reading and writing.	 Unless	getty is invoked with
     the -h flag, getty	will force a hangup on the line	by setting the speed
     to	zero before setting the	speed to the default or	specified speed.  The
     -t	flag plus timeout (in seconds),	specifies that getty should exit if
     the open on the line succeeds and no one types anything in	the specified
     number of seconds.

     The -N option honors the /etc/nologin file.  When present,	getty does not
     answer the	line, but instead waits	for the	file to	go away.

     Speed, the	optional second	argument, is a label to	a speed	and tty
     definition	in the file /etc/gettydefs.  This definition tells getty at
     what speed	to initially run, what the login message should	look like,
     what the initial tty settings are,	and what speed to try next should the
     user indicate that	the speed is inappropriate (by typing a	<break>

     Type, the optional	third argument,	is a character string describing to
     getty what	type of	terminal is connected to the line in question.	getty
     recognizes	the following types:

	  none		 default
	  ds40-1	 Dataspeed40/1
	  tektronix,tek	 Tektronix
	  vt61		 DEC vt61
	  vt100		 DEC vt100
	  hp45		 Hewlett-Packard 45
	  c100		 Concept 100

									Page 1

GETTY(1M)							     GETTY(1M)

     The default terminal is none; i.e., any crt or normal terminal unknown to
     the system.  Also,	for terminal type to have any meaning, the virtual
     terminal handlers must be compiled	into the operating system.  They are
     available,	but not	compiled in the	default	condition.

     Linedisc, the optional fourth argument, is	a character string describing
     which line	discipline to use in communicating with	the terminal.  There
     are two line disciplines.	LDISC0 is the familiar System V	line
     discipline.  LDISC1 is similar to the 4.3BSD ``new	tty driver'' (see
     termio(7)).  LDISC1 is the	default.

     When given	no optional arguments, getty sets the speed of the interface
     to	9600 baud, specifies that raw mode is to be used (awaken on every
     character), that echo is to be suppressed,	either parity allowed, newline
 characters will be converted to carriage return-line feed, and tab
     expansion performed on the	standard output.  It types the login message
     before reading the	user's name a character	at a time.  If a null
     character (or framing error) is received, it is assumed to	be the result
     of	the user pushing the ``break'' key.  This will cause getty to attempt
     the next speed in the series.  The	series that getty tries	is determined
     by	what it	finds in /etc/gettydefs.  Modems which "lock" to a single
     speed, such as most high speed modems, should be used with	a gettydefs
     entry which sticks	to a single speed, such	as dx_19200.  This also
     applies to	devices	that send spurious ``break'' signals.  To allow	baud
     rate cycling on the main serial console, change the ttyd1 entry from
     console to	co_9600.

     After the user's name has been typed in, it is terminated by a new-line
     or	carriage-return	character.  The	latter results in the system being set
     to	treat carriage returns appropriately (see ioctl(2)).

     The user's	name is	scanned	to see if it contains any lower-case
     alphabetic	characters; if not, and	if the name is non-empty, the system
     is	told to	map any	future upper-case characters into the corresponding
     lower-case	characters.

     Finally, login is exec(2)'d with the user's name as an argument.
     Additional	arguments may be typed after the login name.  These are	passed
     to	login, which will place	them in	the environment	(see login(1)).

     If	getty is running on the	graphics console, getty	checks to see if
     autologin is enabled by verifying the existence of	/etc/autologin and
     /etc/autologin.on (see login(1)).	If autologin is	enabled, getty will
     invoke login with the autologin option.

     getty cannot be used on a line that is also to be used by outgoing	calls
     made by uucp, cu, or similar programs.  The very similar uugetty(1M) use
     should be used instead.

     When getty	is invoked with	the -c option and file,	it scans the file as
     if	it were	scanning /etc/gettydefs	during normal operation, and prints
     out the results to	the standard output.  If there are any unrecognized

									Page 2

GETTY(1M)							     GETTY(1M)

     modes or improperly constructed entries, it reports these.	 If the
     entries are correct, it prints out	the values of the various flags.  See
     ioctl(2) to interpret the values.	Note that some values are added	to the
     flags automatically.

FILES    [Toc]    [Back]

     /etc/issue	    message printed before login prompt

SEE ALSO    [Toc]    [Back]

     init(1M), login(1), uugetty(1M), cu(1C), uucp(1C),	ioctl(2),
     gettydefs(4), inittab(4), tty(7), serial(7)

DIAGNOSTICS    [Toc]    [Back]

     Most error	messages are sent to the system	log, /var/adm/SYSLOG.  A
     message similar to

	  getty[5310]: ioctl(TCSETAF)584: Invalid argument

     may indicate that the tty line does not support the baud rate specified
     in	/etc/gettydefs.	 See serial(7) for information on which	baud rates are

BUGS    [Toc]    [Back]

     While getty understands simple single character quoting conventions, it
     is	not possible to	quote certain special control characters used by
     getty.  Thus, you cannot login via	getty and type a #, @, /, !, _,
     backspace,	^U, ^D,	or & as	part of	your login name	or arguments.  getty
     uses them to determine when the end of the	line has been reached, which
     protocol is being used, and what the erase	character is.  They will
     always be interpreted as having their special meaning.

									PPPPaaaaggggeeee 3333
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