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GETTYTAB(5) File Formats Manual GETTYTAB(5)

gettytab — terminal configuration database

gettytab

The gettytab file is a simplified version of the termcap(5) database used to describe terminal lines. The initial terminal login process getty(8) accesses the gettytab file each time it starts, allowing simpler reconfiguration of terminal characteristics. Each entry in the database is used to describe one class of terminals.

There is a default terminal class, default, that is used to set global defaults for all other classes. (That is, the default entry is read, then the entry for the class required is used to override particular settings.)

Refer to termcap(5) for a description of the file layout. The default column below lists defaults obtained if there is no entry in the table obtained, nor one in the special default table.

ap bool false Terminal uses any parity.
bk str 0377 Alternative end-of-line character (input break).
c0 num unused TTY control flags to write messages.
c1 num unused TTY control flags to read login name.
c2 num unused TTY control flags to leave terminal as.
ce bool false Use CRT erase algorithm.
ck bool false Use CRT kill algorithm.
cl str" Screen clear sequence.
co bool false Console; add ‘\n’ after login prompt.
ds str ‘^Y’ Delayed suspend character.
dx bool false Set DECCTLQ.
ec bool false Leave echo OFF.
ep bool false Terminal uses even parity.
er str ‘^?’ Erase character.
et str ‘^D’ End of text (EOF) character.
ev str Initial environment.
fl str ‘^O’ Output flush character.
hc bool false Do not hangup line on last close.
he str Hostname editing string.
hn str hostname Hostname.
ht bool false Terminal has real tabs.
i0 num unused TTY input flags to write messages.
i1 num unused TTY input flags to read login name.
i2 num unused TTY input flags to leave terminal as.
ig bool false Ignore garbage characters in login name.
im str Initial (banner) message.
in str ‘^C’ Interrupt character.
is num unused Input speed.
kl str ‘^U’ Kill character.
l0 num unused TTY local flags to write messages.
l1 num unused TTY local flags to read login name.
l2 num unused TTY local flags to leave terminal as.
lc bool false Terminal has lower case.
lm str login: Login prompt.
ln str ‘^V’ ``Literal next'' character.
lo str /usr/bin/login Program to execute when name obtained.
mb bool false Do flow control based on carrier.
nl bool false Terminal has (or might have) a newline character.
np bool false Terminal uses no parity (i.e., 8-bit characters).
nx str default Next table (for auto speed selection).
o0 num unused TTY output flags to write messages.
o1 num unused TTY output flags to read login name.
o2 num unused TTY output flags to leave terminal as.
op bool false Terminal uses odd parity.
os num unused Output speed.
pc str ‘\0’ Pad character.
pe bool false Use printer (hard copy) erase algorithm.
pf num 0 Delay between first prompt and following flush (seconds).
pp str unused PPP authentication program.
ps bool false Line connected to a MICOM port selector.
qu str ‘^\’ Quit character.
rp str ‘^R’ Line retype character.
rw bool false Do not use raw for input, use cbreak.
sp num unused Line speed (input and output).
su str ‘^Z’ Suspend character.
tc str none Table continuation.
to num 0 Timeout (seconds).
tt str Terminal type (for environment).
ub bool false Do unbuffered output (of prompts etc).
we str ‘^W’ Word erase character.
xc bool false Do not echo control characters as ‘^X’.
xf str ‘^S’ (stop output) character.
xn str ‘^Q’ (start output) character.

The following capabilities are no longer supported by getty(8):

bd num 0 Backspace delay.
cb bool false Use CRT backspace mode.
cd num 0 Carriage-return delay.
f0 num unused TTY mode flags to write messages.
f1 num unused TTY mode flags to read login name.
f2 num unused TTY mode flags to leave terminal as.
fd num 0 Form-feed (vertical motion) delay.
nd num 0 Newline (line-feed) delay.
uc bool false Terminal is known upper case only.

If no line speed is specified, speed will not be altered from that which prevails when getty(8) is entered. Specifying an input or output speed will override line speed for stated direction only.

Terminal modes to be used for the output of the message and for input of the login name, and to leave the terminal set as upon completion, are derived from the boolean flags specified. If the derivation should prove inadequate, any (or all) of these three may be overridden with one of the , , , , , , , , , , , or numeric specifications, which can be used to specify (usually in octal, with a leading ‘0’) the exact values of the flags. These flags correspond to the termios , , , and fields, respectively. Each of these sets must be completely specified to be effective.

Should getty(8) receive a null character (presumed to indicate a line break) it will restart using the table indicated by the entry. If there is none, it will re-use its original table.

Delays are specified in milliseconds; the nearest possible delay available in the TTY driver will be used. Should greater certainty be desired, delays with values 0, 1, 2, and 3 are interpreted as choosing that particular delay algorithm from the driver.

The screen clear string may be preceded by a (decimal) number of milliseconds of delay required (a la termcap(5)). This delay is simulated by repeated use of the pad character .

The initial message and login message ( and ) may include any of the following character sequences, which expand to information about the environment in which getty(8) is running:

%d
The current date.
%h
The hostname of the machine, which is normally obtained from the system using gethostname(3), but may also be overridden by the table entry. In either case it may be edited with the he string. A ‘@’ in the he string causes one character from the real hostname to be copied to the final hostname. A ‘#’ in the he string causes the next character of the real hostname to be skipped. Each character that is neither ‘@’ nor ‘#’ is copied into the final hostname. Surplus ‘@’ and ‘#’ characters are ignored.
%t
The TTY name.
%m, %r, %s, %v
The type of machine, release of the operating system, name of the operating system, and version of the kernel, respectively, as returned by uname(3).
%%
A ‘%’ character.

When getty(8) executes the login process given in the string (usually /usr/bin/login), it will have set the environment to include the terminal type, as indicated by the string (if it exists). The string can be used to enter additional data into the environment. It is a list of comma-separated strings, each of which will presumably be of the form .

If a non-zero timeout is specified with , then getty(8) will exit within the indicated number of seconds, either having received a login name and passed control to login(1), or having received an alarm signal and exited. This may be useful to hangup dial in lines.

Output from getty(8) is even parity unless op or is specified. The op string may be specified with to allow any parity on input, but generate odd parity output. Note: this only applies while getty(8) is being run; terminal driver limitations prevent a more complete implementation. getty(8) does not check parity of input characters in RAW mode.

If a pp string is specified and a PPP link bring-up sequence is recognized, getty(8) will invoke the program referenced by the pp option. This can be used to handle incoming PPP calls.

login(1), gethostname(3), uname(3), termcap(5), getty(8)

The gettytab file format appeared in 4.2BSD.

The special characters (erase, kill, etc.) are reset to system defaults by login(1). In cases, ‘#’ or ‘^H’ typed in a login name will be treated as an erase character, and ‘@’ will be treated as a kill character.

The delay stuff is a real crock. Apart from its general lack of flexibility, some of the delay algorithms are not implemented. The terminal driver should support sane delay settings.

The he capability is stupid.

The termcap(5) format is horrid; something more rational should have been chosen.

December 10, 2013 OpenBSD-5.5