getty(1M) getty(1M)NAME apm_getty, getty - set terminal type, modes, speed, and line discipline SYNOPSIS /etc/getty [-h] [-ttimeout] line [speed [type [linedisc]]] /etc/getty -c file /etc/apm_getty getty-options DESCRIPTION getty is a program that is invoked by init(1M) and is the second process in the series (init-getty-login-shell) that ultimately connects a user with the A/UX(Reg.) system. get- ty generates a login message field for the entry it is using from /etc/gettydefs. Then getty reads the user's login name and invokes the login(1) command with the user's name as ar- gument. While reading the name, getty attempts to adapt the system to the speed and type of terminal being used. apm_getty provides functionality beyond normal getty for use with an Apple(Reg.) Personal Modem. Before it turns over control to getty, apm_getty sends the control sequence to select auto-answer mode. To switch back to a dialout line, the line containing apm_getty in /etc/inittab should be changed to off instead of respawn. To activate these changes, use init q as described in init(1M). The name of a tty line in /dev to which getty is to attach itself is line. 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 option, getty forces a hangup on the line by setting the speed to 0 before setting the speed to the default or specified speed. The -t flag option plus timeout in seconds, specifies that getty should exit if the open on the line succeeds and no one types anything during the specified number of seconds. The optional second argument, speed, is a label to a speed and tty definition in the file /etc/gettydefs. This definition tells getty at what speed the interface should initially run, what the login message should look like, what the ini- tial tty settings are, and what speed should be tried next should the user indicate that the speed is inappropriate by typing a break character. The default speed is 300 baud. The optional third argument, type, is a character string describing to getty what type of terminal is connected to the line in question. getty understands the following types: none Default vt61 DEC vt61 vt100 DEC vt100 c100 Concept 100 April, 1990 1
getty(1M) getty(1M)The default terminal is none, that is, any CRT or normal terminal unknown to the system. Also, for the 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. The optional fourth argument, linedisc, is a character string describing which line discipline to use in communicating with the terminal. Again, the hooks for line disciplines are available in the operating system, but only one is presently available, the default line discipline LDISC0. When given no optional arguments, getty sets the speed of the interface to 300 baud, specifies that raw mode is to be used (awaken on every character), that echo is to be suppressed, that either parity is allowed, that newline characters are to be converted to return-line feed, and that tab expansion be performed on the standard output. It types the login message before reading the user's name one charac- ter 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. The user's name is terminated by a newline or RETURN charac- ter. The latter results in the system being set to treat RETURN characters 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 nonempty, the system is told to map any future uppercase characters into the corresponding lowercase characters. In addition to the standard A/UX system erase and kill char- acters (DELETE and CONTROL-U), getty also understands \b as an erase. getty sets the standard erase character or kill character to match. getty also understands the ``standard'' ESS protocols for erasing, killing, aborting, and terminating a line. If get- ty sees the ESS erase character, _, or kill character, $, or abort character, &, or the ESS line terminators, / or !, it arranges for this set of characters to be used for these functions. Finally, login is called with the user's name as an argu- ment. Additional arguments may be typed after the login name. These are passed to login, which places them in the environment. See login(1). A check option is provided. When getty is invoked with the -c option and file, it scans the file as if it were scanning 2 April, 1990
getty(1M) getty(1M)/etc/gettydefs and prints out the results to the standard output. If there are any unrecognized 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. getty attempts to prevent the communication programs cu(1), tip(1), and uucico(1M) from interfering with its operation by creating a lock file in /usr/spool/uucp. The lock file is not created by getty until input is present, so that these programs may attempt to access line while getty is running. FILES /etc/getty /etc/gettydefs /etc/issue /usr/spool/uucp/LCK..line SEE ALSO ct(1C), init(1M), login(1), ioctl(2), gettydefs(4), inittab(4), tty(7). BUGS Although getty understands simple single-character quoting conventions, it is not possible to quote the special control characters that getty uses to determine when the end of the line has been reached, which protocol is being used, and what the erase character is. Therefore, it is not possible to login via getty and type a #, @, /, !, _, DELETE, CONTROL-U, CONTROL-D, or & as part of your login name or ar- gument. They are always interpreted as having their special meaning, as described earlier. April, 1990 3