mgettydefs(4)
mgettydefs(4)
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 simi-
lar 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 exten-
sions. 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 con-
verted to other values. The sequences and their substitu-
tions 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) set-
tings 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 usu-
ally 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 set-
tings 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:
<character name> <value>
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, suit-
able for mgetty:
19200mg#
B19200 #
B19200 SANE VERASE \b VINTR \003 HUPCL #
\n\D \T \N Users @!login: #19200mg
FILES
/etc/gettydefs
SEE ALSO
mgetty(8) getty(8) login(1) ioctl(2) termio(7)
termios(7).