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AGETTY(8)							     AGETTY(8)

       getty - alternative Linux getty

       getty  [-ihLmnw] [-f issue_file] [-l login_program] [-I init] [-t time
       out] [-H login_host] port baud_rate,...	[term]
       getty [-ihLmnw] [-f issue_file] [-l login_program] [-I init] [-t  time
       out] [-H login_host] baud_rate,...  port [term]

       getty  opens  a	tty  port,  prompts  for  a login name and invokes the
       /bin/login command. It is normally invoked by init(8).

       getty has several non-standard features that are useful for  hard-wired
       and for dial-in lines:

       o      Adapts  the tty settings to parity bits and to erase, kill, end-
	      of-line and uppercase characters when it	reads  a  login  name.
	      The  program can handle 7-bit characters with even, odd, none or
	      space parity, and 8-bit characters with no parity. The following
	      special  characters  are	recognized: @ and Control-U (kill); #,
	      DEL and back space (erase); carriage return and line  feed  (end
	      of line).

       o      Optionally  deduces the baud rate from the CONNECT messages pro
	      duced by Hayes(tm)-compatible modems.

       o      Optionally does not hang up when it is given an  already	opened
	      line (useful for call-back applications).

       o      Optionally does not display the contents of the /etc/issue file.

       o      Optionally  displays  an	alternative  issue  file  instead   of

       o      Optionally does not ask for a login name.

       o      Optionally  invokes  a  non-standard  login  program  instead of

       o      Optionally turns on hard-ware flow control

       o      Optionally forces the line to be local with no need for  carrier

       This  program  does  not use the /etc/gettydefs (System V) or /etc/get
       tytab (SunOS 4) files.

       port   A path name relative to the /dev directory. If a "-"  is	speci
	      fied, getty assumes that its standard input is already connected
	      to a tty port and that a connection to a remote user has already
	      been established.

	      Under  System  V,  a  "-"  port argument should be preceded by a

	      A comma-separated list of one or	more  baud  rates.  Each  time
	      getty  receives  a BREAK character it advances through the list,
	      which is treated as if it were circular.

	      Baud rates should be specified in descending order, so that  the
	      null  character  (Ctrl-@) can also be used for baud rate switch

       term   The value to be used for the  TERM  environment  variable.  This
	      overrides  whatever  init(8)  may  have set, and is inherited by
	      login and the shell.

       -h     Enable hardware (RTS/CTS) flow control. It is  left  up  to  the
	      application  to  disable software (XON/XOFF) flow protocol where

       -i     Do not display the contents  of  /etc/issue  (or	other)	before
	      writing  the  login prompt. Terminals or communications hardware
	      may become confused when receiving lots of  text	at  the  wrong
	      baud  rate; dial-up scripts may fail if the login prompt is pre
	      ceded by too much text.

       -f issue_file
	      Display the contents of issue_file instead of /etc/issue.   This
	      allows  custom  messages to be displayed on different terminals.
	      The -i option will override this option.

       -I initstring
	      Set an initial string to be sent to  the	tty  or  modem	before
	      sending  anything  else. This may be used to initialize a modem.
	      Non printable characters may be sent by writing their octal code
	      preceded	by  a  backslash  (\).	For example to send a linefeed
	      character (ASCII 10, octal 012) write \012.

       -l login_program
	      Invoke the specified login_program instead of /bin/login.   This
	      allows the use of a non-standard login program (for example, one
	      that asks for a dial-up password or that uses a different  pass
	      word file).

       -H login_host
	      Write the specified login_host into the utmp file. (Normally, no
	      login host is given, since getty is  used  for  local  hardwired
	      connections and consoles. However, this option can be useful for
	      identifying terminal concentrators and the like.

       -m     Try to extract the baud rate the CONNECT status message produced
	      by Hayes(tm)-compatible modems. These status messages are of the
	      form: "".  getty assumes that the modem emits
	      its  status  message  at	the  same speed as specified with (the
	      first) baud_rate value on the command line.

	      Since the -m feature may fail  on  heavily-loaded  systems,  you
	      still should enable BREAK processing by enumerating all expected
	      baud rates on the command line.

       -n     Do not prompt the user for a login name. This  can  be  used  in
	      connection with -l option to invoke a non-standard login process
	      such as a BBS system. Note that with the -n option,  getty  gets
	      no  input  from  user who logs in and therefore wont be able to
	      figure out parity, character size, and newline processing of the
	      connection.  It  defaults to space parity, 7 bit characters, and
	      ASCII CR (13) end-of-line character.  Beware  that  the  program
	      that getty starts (usually /bin/login) is run as root.

       -t timeout
	      Terminate  if no user name could be read within timeout seconds.
	      This option should probably not be used with hard-wired lines.

       -L     Force the line to be a local  line  with	no  need  for  carrier
	      detect. This can be useful when you have a locally attached ter
	      minal where the serial line does not set the carrier detect sig

       -w     Wait  for  the  user or the modem to send a carriage-return or a
	      linefeed character before sending the /etc/issue (or other) file
	      and  the	login  prompt.	Very  useful in connection with the -I

       This section shows examples for the process field of an	entry  in  the
       /etc/inittab  file.   Youll have to prepend appropriate values for the
       other fields.  See inittab(5) for more details.

       For a hard-wired line or a console tty:
	    /sbin/getty 9600 ttyS1

       For a  directly	connected  terminal  without  proper  carriage	detect
       wiring:	(try this if your terminal just sleeps instead of giving you a
       password: prompt.)
	    /sbin/getty -L 9600 ttyS1 vt100

       For a old style dial-in line with a 9600/2400/1200 baud modem:
	    /sbin/getty -mt60 ttyS1 9600,2400,1200

       For a Hayes modem with a fixed 115200 bps  interface  to  the  machine:
       (the  example  init string turns off modem echo and result codes, makes
       modem/computer DCD track modem/modem DCD, makes a DTR drop cause a dis-
       connection and turn on auto-answer after 1 ring.)
	    /sbin/getty -w -I ATE0Q1&D2&C1S0=1\015 115200 ttyS1

       The issue-file (/etc/issue or the file set with the -f option) may con
       tain certain escape codes to display the system	name,  date  and  time
       etc.  All  escape codes consist of a backslash (\) immediately followed
       by one of the letters explained below.

       b      Insert the baudrate of the current line.

       d      Insert the current date.

       s      Insert the system name, the name of the operating system.

       l      Insert the name of the current tty line.

       m      Insert the architecture identifier of the machine, eg. i486

       n      Insert the nodename of the machine, also known as the  hostname.

       o      Insert the domainname of the machine.

       r      Insert the release number of the OS, eg. 1.1.9.

       t      Insert the current time.

       u      Insert the number of current users logged in.

       U      Insert  the string "1 user" or " users" where  is the num
	      ber of current users logged in.

       v      Insert the version of the OS, eg. the build-date etc.

       Example: On my system, the following /etc/issue file:

	      This is \n.\o (\s \m \r) \t

       displays as

	      This is thingol.orcan.dk (Linux i386 1.1.9) 18:29:30

       /var/run/utmp, the system status file.
       /etc/issue, printed before the login prompt.
       /dev/console, problem reports (if syslog(3) is not used).
       /etc/inittab, init(8) configuration file.

       The baud-rate detection feature (the -m option) requires that getty  be
       scheduled  soon enough after completion of a dial-in call (within 30 ms
       with modems that talk at 2400 baud). For robustness, always use the  -m
       option  in combination with a multiple baud rate command-line argument,
       so that BREAK processing is enabled.

       The text in the /etc/issue file (or other) and  the  login  prompt  are
       always output with 7-bit characters and space parity.

       The baud-rate detection feature (the -m option) requires that the modem
       emits its status message after raising the DCD line.

       Depending on how the program was configured, all diagnostics are  writ
       ten  to	the  console  device  or  reported via the syslog(3) facility.
       Error messages are produced if the port argument  does  not  specify  a
       terminal  device;  if  there  is  no utmp entry for the current process
       (System V only); and so on.

       W.Z. Venema 
       Eindhoven University of Technology
       Department of Mathematics and Computer Science
       Den Dolech 2, P.O. Box 513, 5600 MB Eindhoven, The Netherlands

       Peter Orbaek 
       Linux port and more options. Still maintains the code.

       Eric Rasmussen 
       Added -f option to display custom login messages on different terminals.

       Sat Nov 25 22:51:05 MET 1989



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