libexec/getty/gettytab.5

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.\"     from: @(#)gettytab.5	8.4 (Berkeley) 4/19/94
.\"
.Dd $Mdocdate: May 27 2017 $
.Dt GETTYTAB 5
.Os
.Sh NAME
.Nm gettytab
.Nd terminal configuration database
.Sh DESCRIPTION
The
.Nm
file
is a simplified version of the
.Xr termcap 5
database
used to describe terminal lines.
The initial terminal login process
.Xr getty 8
accesses the
.Nm
file each time it starts, allowing simpler
reconfiguration of terminal characteristics.
Each entry in the database
is used to describe one class of terminals.
.Pp
There is a default terminal class,
.Em default ,
that is used to set global defaults for all other classes.
(That is, the
.Em default
entry is read, then the entry for the class required
is used to override particular settings.)
.Sh CAPABILITIES
Refer to
.Xr termcap 5
for a description of the file layout.
The
.Em default
column below lists defaults obtained if there is
no entry in the table obtained, nor one in the special
.Em default
table.
.Bl -column "Name" "Type" "Default" "Description"
.It Sy Name Ta Sy Type Ta Sy Default Ta Sy Description
.It ap Ta bool Ta false Ta "Terminal uses any parity."
.It bk Ta str Ta 0377 Ta "Alternative end-of-line character (input break)."
.It c0 Ta num Ta unused Ta "TTY control flags to write messages."
.It c1 Ta num Ta unused Ta "TTY control flags to read login name."
.It c2 Ta num Ta unused Ta "TTY control flags to leave terminal as."
.It ce Ta bool Ta false Ta "Use CRT erase algorithm."
.It ck Ta bool Ta false Ta "Use CRT kill algorithm."
.It cl Ta str Ta Dv NULL Ta "Screen clear sequence."
.It co Ta bool Ta false Ta "Console; add"
.Ql \en
after login prompt.
.It ds Ta str Ta So Li ^Y Sc Ta "Delayed suspend character."
.It dx Ta bool Ta false Ta "Set"
.Dv DECCTLQ .
.It ec Ta bool Ta false Ta "Leave echo OFF."
.It ep Ta bool Ta false Ta "Terminal uses even parity."
.It er Ta str Ta So Li ^? Sc Ta "Erase character."
.It et Ta str Ta So Li ^D Sc Ta "End of text"
.Pq Dv EOF
character.
.It ev Ta str Ta Dv NULL Ta "Initial environment."
.It fl Ta str Ta So Li ^O Sc Ta "Output flush character."
.It hc Ta bool Ta false Ta "\&Do"
.Em not
hangup line on last close.
.It hn Ta str Ta hostname Ta "Hostname."
.It ht Ta bool Ta false Ta "Terminal has real tabs."
.It i0 Ta num Ta unused Ta "TTY input flags to write messages."
.It i1 Ta num Ta unused Ta "TTY input flags to read login name."
.It i2 Ta num Ta unused Ta "TTY input flags to leave terminal as."
.It ig Ta bool Ta false Ta "Ignore garbage characters in login name."
.It im Ta str Ta Dv NULL Ta "Initial (banner) message."
.It in Ta str Ta So Li ^C Sc Ta "Interrupt character."
.It is Ta num Ta unused Ta "Input speed."
.It kl Ta str Ta So Li ^U Sc Ta "Kill character."
.It l0 Ta num Ta unused Ta "TTY local flags to write messages."
.It l1 Ta num Ta unused Ta "TTY local flags to read login name."
.It l2 Ta num Ta unused Ta "TTY local flags to leave terminal as."
.It lc Ta bool Ta false Ta "Terminal has lower case."
.It lm Ta str Ta login: Ta "Login prompt."
.It ln Ta str Ta So Li ^V Sc Ta "``Literal next'' character."
.It lo Ta str Ta Pa /usr/bin/login Ta "Program to execute when name obtained."
.It mb Ta bool Ta false Ta "\&Do flow control based on carrier."
.It nl Ta bool Ta false Ta "Terminal has (or might have) a newline character."
.It np Ta bool Ta false Ta "Terminal uses no parity (i.e., 8-bit characters)."
.It nx Ta str Ta default Ta "Next table (for auto speed selection)."
.It o0 Ta num Ta unused Ta "TTY output flags to write messages."
.It o1 Ta num Ta unused Ta "TTY output flags to read login name."
.It o2 Ta num Ta unused Ta "TTY output flags to leave terminal as."
.It op Ta bool Ta false Ta "Terminal uses odd parity."
.It os Ta num Ta unused Ta "Output speed."
.It pc Ta str Ta So Li \e0 Sc Ta "Pad character."
.It pe Ta bool Ta false Ta "Use printer (hard copy) erase algorithm."
.It pf Ta num Ta 0 Ta "Delay"
between first prompt and following flush (seconds).
.It ps Ta bool Ta false Ta "Line connected to a MICOM port selector."
.It qu Ta str Ta So Li \&^\e Sc Ta "Quit character."
.It rp Ta str Ta So Li ^R Sc Ta "Line retype character."
.It rw Ta bool Ta false Ta "\&Do"
.Em not
use raw for input, use cbreak.
.It sp Ta num Ta unused Ta "Line speed (input and output)."
.It su Ta str Ta So Li ^Z Sc Ta "Suspend character."
.It tc Ta str Ta none Ta "Table continuation."
.It to Ta num Ta 0 Ta "Timeout (seconds)."
.It tt Ta str Ta Dv NULL Ta "Terminal type (for environment)."
.It ub Ta bool Ta false Ta "\&Do unbuffered output (of prompts etc)."
.It we Ta str Ta So Li ^W Sc Ta "Word erase character."
.It xc Ta bool Ta false Ta "\&Do"
.Em not
echo control characters as
.Ql ^X .
.It xf Ta str Ta So Li ^S Sc Ta Dv XOFF
(stop output) character.
.It xn Ta str Ta So Li ^Q Sc Ta Dv XON
(start output) character.
.El
.Pp
The following capabilities are no longer supported by
.Xr getty 8 :
.Bl -column "bd" "bool" "flase" "description"
.It bd Ta num Ta 0 Ta "Backspace delay."
.It cb Ta bool Ta false Ta "Use CRT backspace mode."
.It cd Ta num Ta 0 Ta "Carriage-return delay."
.It f0 Ta num Ta unused Ta "TTY mode flags to write messages."
.It f1 Ta num Ta unused Ta "TTY mode flags to read login name."
.It f2 Ta num Ta unused Ta "TTY mode flags to leave terminal as."
.It fd Ta num Ta 0 Ta "Form-feed (vertical motion) delay."
.It nd Ta num Ta 0 Ta "Newline (line-feed) delay."
.It uc Ta bool Ta false Ta "Terminal is known upper case only."
.El
.Pp
If no line speed is specified, speed will not be altered
from that which prevails when
.Xr getty 8
is entered.
Specifying an input or output speed will override
line speed for stated direction only.
.Pp
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
.Em \&c0 ,
.Em \&c1 ,
.Em \&c2 ,
.Em \&i0 ,
.Em \&i1 ,
.Em \&i2 ,
.Em \&l0 ,
.Em \&l1 ,
.Em \&l2 ,
.Em \&o0 ,
.Em \&o1 ,
or
.Em \&o2
numeric specifications, which can be used to specify
(usually in octal, with a leading
.Ql 0 )
the exact values of the flags.
These flags correspond to the termios
.Em c_cflag ,
.Em c_iflag ,
.Em c_lflag ,
and
.Em c_oflag
fields, respectively.
Each of these sets must be completely specified to be effective.
.Pp
Should
.Xr getty 8
receive a null character
(presumed to indicate a line break)
it will restart using the table indicated by the
.Em nx
entry.
If there is none, it will re-use its original table.
.Pp
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.
.Pp
The
.Em \&cl
screen clear string may be preceded by a (decimal) number
of milliseconds of delay required (a la
.Xr termcap 5 ) .
This delay is simulated by repeated use of the pad character
.Em \&pc .
.Pp
The initial message and login message
.Po
.Em \&im
and
.Em \&lm
.Pc
may include any of the following character sequences, which expand to
information about the environment in which
.Xr getty 8
is running:
.Bl -tag -width \&%xxx
.It \&%d
The current date.
.It \&%h
The hostname of the machine, which is normally obtained from the
system using
.Xr gethostname 3 ,
but may also be overridden by the
.Em \&hn
table entry.
.It \&%t
The TTY name.
.It "\&%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
.Xr uname 3 .
.It \&%%
A
.Ql %
character.
.El
.Pp
When
.Xr getty 8
executes the login process given in the
.Em \&lo
string (usually
.Pa /usr/bin/login ) ,
it will have set
the environment to include the terminal type, as indicated
by the
.Em \&tt
string (if it exists).
The
.Em \&ev
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
.Em name=value .
.Pp
If a non-zero timeout is specified with
.Em \&to ,
then
.Xr getty 8
will exit within the indicated number of seconds, either having
received a login name and passed control to
.Xr login 1 ,
or having received an alarm signal and exited.
This may be useful to hangup dial in lines.
.Pp
Output from
.Xr getty 8
is even parity unless
.Em \&op
or
.Em \&np
is specified.
The
.Em \&op
string
may be specified with
.Em \&ap
to allow any parity on input, but generate odd parity output.
Note: this only applies while
.Xr getty 8
is being run;
terminal driver limitations prevent a more complete implementation.
.Xr getty 8
does not check parity of input characters in
.Dv RAW
mode.
.Pp
If a
.Em \&pp
string is specified and a PPP link bring-up sequence is recognized,
.Xr getty 8
will invoke the program referenced by the
.Em \&pp
option.
This can be used to handle incoming PPP calls.
.Sh FILES
.Bl -tag -width "/etc/gettytab" -compact
.It Pa /etc/gettytab
Default location of the database file.
.El
.Sh SEE ALSO
.Xr login 1 ,
.Xr gethostname 3 ,
.Xr uname 3 ,
.Xr termcap 5 ,
.Xr getty 8
.Sh HISTORY
The
.Nm
file format appeared in
.Bx 4.2 .
.Sh BUGS
The special characters (erase, kill, etc.) are reset to system defaults by
.Xr login 1 .
.Pp
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.
.Pp
The
.Xr termcap 5
format is horrid; something more rational should have been chosen.