Ubuntu Manpage: mgettydefs - speed and terminal settings used by mgetty

NAME

       mgettydefs - speed and terminal settings used by mgetty

DESCRIPTION

The /etc/gettydefs file contains information used by mgetty(1) to set up the speed and
terminal settings for a line. It also supplies information on what the login prompt
should look like.

Many versions of UNIX have a version of getty(1) that also reads /etc/gettydefs. Both
mgetty and getty expect similar formats in /etc/gettydefs except that, when used by
mgetty, extended functionality is available. Even so, the additional functions are simply
ignored by standard getty, so they can co-exist using the same file. Note, however, that
mgetty can be compiled to use a file different from /etc/gettydefs if your getty gets
upset about the extensions. This manual page documents /etc/gettydefs and describes the
extended functionality available when used by mgetty(1). This document will refer to
getty(1) except where mgetty's behaviour is different.

Each entry in /etc/gettydefs has the following format:

label# initial-flags # final-flags # login-prompt #next-label

Each entry is followed by a blank line. The login prompt field can contain quoted
characters which will be converted to other values. The sequences and their substitutions
are:

\n newline

\r carriage return

\g beep

\b backspace

\v vertical tab (VT)

\f formfeed

\t tab

\L portname

\C time in ctime(3) format.

\N number of users currently logged in

\U number of users currently logged in

\D date in DD/MM format

\T time in hh:mm:ss format

\I modem CONNECT attributes

\sequence where "sequence" is a valid strtol format, such as: \0nnn (octal), \0xnnn
(hex), or \nnn (decimal).

Note that standard getty usually only supports \b, \r and \n.

The various fields are:

label This is the string against which getty tries to match its second argument.
It is often the speed, such as 1200, at which the terminal is supposed to
run, but it need not be (see below).

initial-flags These flags are the initial ioctl(2) settings to which the terminal is to
be set if a terminal type is not specified to getty. The flags that getty
understands are the ones listed in termio(7)). mgetty is usually compiled
for termios(7) and often has a more complete set than getty.

Normally only the speed flag is required in the
initial-flags. getty automatically sets the terminal to raw input mode and
takes care of the other flags. If the "-s" option is used with mgetty(1)
the speed setting is ignored. The initial-flag settings remain in effect
until getty executes login(1).

final-flags These flags take the same values as the initial-flags and are set just
before getty executes login. The speed flag is again required, except with
mgetty if the -s flag was supplied. Two other commonly specified final-
flags are TAB3, so that tabs are sent to the terminal as spaces, and HUPCL,
so that the line is hung up on the final close.

login-prompt This entire field is printed as the login-prompt. Unlike the above fields
where white space (a space, tab or new-line) is ignored, they are included
in the login-prompt field. This field is ignored if the "-p" option has
been specified to mgetty(1).

next-label specifies the label to use if the user user types a <break> character, or
getty detects a reception error. Getty searches for the entry with next-
label as its label field and set up the terminal for those settings.
Usually, a series of speeds are linked together in this fashion, into a
closed set; for instance, 2400 linked to 1200, which in turn is linked to
300, which finally is linked to 2400. next-label is ignored with
mgetty(1).

Several additional composite settings are available for initial-flags and final-flags.
The following composite flags are supported by mgetty and are usually supported by getty:

SANE equivalent to ``stty sane''. (BRKINT, IGNPAR, ISTRIP, ICRNL, IXON,
OPOST, CS8, CREAD, ISIG, ICANON, ECHO, ECHOK)

ODDP Odd parity (CS7, PARENB, PARODD)

PARITY,EVENP even parity (CS7, PARENB)

-ODDP,-PARITY,-EVENP
no parity (resets PARENB, PARODD, and sets CS8)

RAW raw I/O (no canonical processing) (turns off OPOST, ICANON)

-RAW,COOKED enable canonical processing (turns on OPOST, ICANON)

NL Ignore newlines. (ICRNL, ONLCR)

-NL Respect newlines (turns INLCR, IGNCR, ICRNL, ONLCR, OCRNL, ONLRET off)

LCASE Ignore case - treat all as lowercase. (IUCLC, OLCUC, XCASE) Is set if
mgetty believes login is entirely uppercase.

-LCASE Repect case (turns off IUCLC, OLCUC and XCASE)

TABS output tabs as tabs

-TABS,TAB3 output tabs as spaces

EK Sets VERASE to "#" and VKILL to CKILL respectively. (note that while
many gettys default VERASE to "#". mgetty defaults VERASE to
backspace.)

Additionally, mgetty (but not getty) can set any of the control characters listed in the
c_cc termio(termios) structure by the use of two tokens:

Eg:

VERASE ^h

The value can be set as ``^<character>'', ``\nnn'' or ``\<character>'' (normal UNIX \
escapes).

See the termio(7) or termios(7) manual pages to a list of which ``V'' variables can be
changed. Note that many of these can be changed in the c_cc array, but won't have any
effect.

If getty is called without a second argument, the first entry of /etc/gettydefs is used by
getty, thus making the first entry of /etc/gettydefs the default entry. It is also used
if getty cannot find the specified label. Mgetty use a default label of ``n'', but this
can be changed in the configuration. If /etc/gettydefs itself is missing, there is one
entry built into the command which brings up a terminal at 300 (configuration parameter in
mgetty) baud.

It is strongly recommended that after making or modifying /etc/gettydefs, it be run
through getty with the check option to be sure there are no errors.

EXAMPLES

       The following two lines show an example of 300/1200 baud toggle, which is useful for dial-
       up ports:

              1200# B1200 HUPCL # B1200 SANE IXANY TAB3 #login: #300
              300# B300 HUPCL # B300 SANE IXANY TAB3 #login: #1200

       The following line shows a typical 9600  baud  entry  for  a  hard-wired  connection  (not
       currently supported for mgetty):

              9600# B9600 # B9600 SANE IXANY IXANY ECHOE TAB3 #login: #9600

       The following line is a typical smart-modem setup, suitable for mgetty:

              19200mg#
                  B19200 #
                  B19200 SANE VERASE \b VINTR \003 HUPCL #
                  \n\D \T \N Users @!login: #19200mg

FILES

       /etc/gettydefs

NAME

DESCRIPTION

EXAMPLES

FILES

SEE ALSO