Entries in termcap consist of a number of `:'-separated fields. The first entry for each terminal gives the names that are known for the terminal, separated by `|' characters. The first name given is the most common abbreviation for the terminal. The last name given should be a long name fully identifying the terminal, and all others are understood as synonyms for the terminal name. All names but the last should be in lower case and contain no blanks; the last name may well contain upper case characters and blanks for readability.
Terminal names (except for the last, verbose entry) should be chosen using the following conventions. The particular piece of hardware making up the terminal should have a root name chosen, thus ``hp2621'' This name should not contain hyphens. Modes that the hardware can be in or user preferences should be indicated by appending a hyphen and an indicator of the mode. Therefore, a ``vt100'' in 132-column mode would be ``vt100-w''. The following suffixes should be used where possible:
Suffix Meaning Example -w Wide mode (more than 80 columns) vt100-w -am With automatic margins (usually default) vt100-am -nam Without automatic margins vt100-nam -n
Number of lines on screen aaa-60 -na No arrow keys (leave them in local) concept100-na -np Number of pages of memory concept100-4p -rv Reverse video concept100-rv
N indicates numeric parameter(s) P indicates that padding may be specified * indicates that padding may be based on the number of lines affected o indicates capability is obsolete
``Obsolete'' capabilities have no terminfo equivalents, since they were considered useless, or are subsumed by other capabilities. New software should not rely on them at all.
!1 str Sent by shifted save key. | |
!2 str Sent by shifted suspend key. | |
!3 str Sent by shifted undo key. | |
#1 str Sent by shifted help key. | |
#2 str Sent by shifted home key. | |
#3 str Sent by shifted input key. | |
#4 str Sent by shifted left-arrow key. | |
%0 str Sent by redo key. | |
%1 str Sent by help key. | |
%2 str Sent by mark key. | |
%3 str Sent by message key. | |
%4 str Sent by move key. | |
%5 str Sent by next-object key. | |
%6 str Sent by open key. | |
%7 str Sent by options key. | |
%8 str Sent by previous-object key. | |
%9 str Sent by print or copy key. | |
%a str Sent by shifted message key. | |
%b str Sent by shifted move key. | |
%c str Sent by shifted next key. | |
%d str Sent by shifted options key. | |
%e str Sent by shifted prev key. | |
%f str Sent by shifted print key. | |
%g str Sent by shifted redo key. | |
%h str Sent by shifted replace key. | |
%i str Sent by shifted right-arrow key. | |
%j str Sent by shifted resume key. | |
&0 str Sent by shifted cancel key. | |
&1 str Sent by ref(erence) key. | |
&2 str Sent by refresh key. | |
&3 str Sent by replace key. | |
&4 str Sent by restart key. | |
&5 str Sent by resume key. | |
&6 str Sent by save key. | |
&7 str Sent by suspend key. | |
&8 str Sent by undo key. | |
&9 str Sent by shifted begin key. | |
*0 str Sent by shifted find key. | |
*1 str Sent by shifted command key. | |
*2 str Sent by shifted copy key. | |
*3 str Sent by shifted create key. | |
*4 str Sent by shifted delete-character key. | |
*5 str Sent by shifted delete-line key. | |
*6 str Sent by shifted select key. | |
*7 str Sent by shifted end key. | |
*8 str Sent by shifted clear-to-end-of-line key. | |
*9 str Sent by shifted exit key. | |
@0 str Sent by find key. | |
@1 str Sent by begin key. | |
@2 str Sent by cancel key. | |
@3 str Sent by close key. | |
@4 str Sent by command key. | |
@5 str Sent by copy key. | |
@6 str Sent by create key. | |
@7 str Sent by end key. | |
@8 str Sent by enter key. | |
@9 str Sent by exit key. | |
AB str Set background color to #1 using ANSI escape. | |
ac str Alternative (graphic) character set pairs. | |
ae str (P) End alternative character set. | |
AL str (NP*) Add" n new blank lines | |
AF str Set foreground color to #1 using ANSI escape. | |
al str (P*) Add new blank line. | |
am bool Terminal has automatic margins. | |
as str (P) Start alternative character set. | |
bc str (o) Backspace if not ^H. | |
bl str (P) Audible signal (bell). | |
bs bool (o) Terminal can backspace with ^H. | |
bt str (P) Back tab. | |
bw bool | le (backspace) wraps from column 0 to last column. |
CC str Terminal settable command character in prototype. | |
cc bool Terminal can re-define existing color. | |
cd str (P*) Clear to end of display. | |
ce str (P) Clear to end of line. | |
ch str (NP) Set cursor column (horizontal position). | |
cl str (P*) Clear screen and home cursor. | |
CM str (NP) Memory-relative cursor addressing. | |
cm str (NP) Screen-relative cursor motion. | |
Co num Maximum number of colors on the screen. | |
co num Number of columns in a line (See BUGS section below). | |
cr str (P) Carriage return. | |
cs str (NP) Change scrolling region (VT100). | |
ct str (P) Clear all tab stops. | |
cv str (NP) Set cursor row (vertical position). | |
da bool Display may be retained above the screen. | |
dB num (o) Milliseconds of bs delay needed (default 0). | |
db bool Display may be retained below the screen. | |
DC str (NP*) Delete n characters. | |
dC num (o) Milliseconds of cr delay needed (default 0). | |
dc str (P*) Delete character. | |
dF num (o) Milliseconds of ff delay needed (default 0). | |
DL str (NP*) Delete n lines. | |
dl str (P*) Delete line. | |
dm str Enter delete mode. | |
dN num (o) Milliseconds of nl delay needed (default 0). | |
DO str (NP*) Move cursor down: n lines. | |
do str Down one line. | |
ds str Disable status line. | |
dT num (o) Milliseconds of horizontal tab delay needed (default 0). | |
dV num (o) Milliseconds of vertical tab delay needed (default 0). | |
eA str Enable alternate character set. | |
ec str (NP) Erase n characters. | |
ed str End delete mode. | |
ei str End insert mode. | |
eo bool Can erase overstrikes with a blank. | |
EP bool (o) Even parity. | |
es bool Escape can be used on the status line. | |
F1-F9 str Sent by function keys 11-19. | |
FA-FZ str Sent by function keys 20-45. | |
Fa-Fr str Sent by function keys 46-63. | |
ff str (P*) Hardcopy terminal page eject. | |
fs str Return from status line. | |
gn bool Generic line type, for example dialup, switch). | |
hc bool Hardcopy terminal. | |
HD bool (o) Half-duplex. | |
hd str Half-line down (forward 1/2 linefeed). | |
hl bool Terminal uses only HLS color notation (Tektronix). | |
ho str (P) Home cursor. | |
hs bool Has extra ``status line''. | |
hu str Half-line up (reverse 1/2 linefeed). | |
hz bool Cannot print ``~'' (Hazeltine). | |
i1-i3 str Terminal initialization strings (terminfo(5) only) | |
IC str (NP*) Insert n blank characters. | |
Ic str Set color #1 to RGB #2, #3, #4. | |
ic str (P*) Insert character. | |
if str Name of file containing initialization string. | |
im str Enter insert mode. | |
in bool Insert mode distinguishes nulls. | |
Ip str Set color-pair #1 to fg #2, bg #3. | |
iP str Pathname of program for initialization (terminfo(5) only). | |
ip str (P*) Insert pad after character inserted. | |
is str Terminal initialization string (termcap only). | |
it num Tabs initially every n positions. | |
K1 str Sent by keypad upper left. | |
K2 str Sent by keypad center. | |
K3 str Sent by keypad upper right. | |
K4 str Sent by keypad lower left. | |
K5 str Sent by keypad lower right. | |
k0-k9 str Sent by function keys 0-9. | |
k; str Sent by function key 10. | |
kA str Sent by insert-line key. | |
ka str Sent by clear-all-tabs key. | |
kB str Sent by back-tab key. | |
kb str Sent by backspace key. | |
kC str Sent by clear-screen or erase key. | |
kD str Sent by delete-character key. | |
kd str Sent by down-arrow key. | |
kE str Sent by clear-to-end-of-line key. | |
ke str Out of ``keypad transmit'' mode. | |
kF str Sent by scroll-forward/down key. | |
kH str Sent by home-down key. | |
kh str Sent by home key. | |
kI str Sent by insert-character or enter-insert-mode key. | |
kL str Sent by delete-line key. | |
kl str Sent by left-arrow key. | |
kM str Sent by insert key while in insert mode. | |
Km str Mouse event has occurred. | |
km bool Has a ``meta'' key (shift, sets parity bit). | |
kN str Sent by next-page key. | |
kn num (o) Number of function (k0- k9) keys (default 0). | |
ko str (o) Termcap entries for other non-function keys. | |
kP str Sent by previous-page key. | |
kR str Sent by scroll-backward/up key. | |
kr str Sent by right-arrow key. | |
kS str Sent by clear-to-end-of-screen key. | |
ks str Put terminal in ``keypad transmit'' mode. | |
kT str Sent by set-tab key. | |
kt str Sent by clear-tab key. | |
ku str Sent by up-arrow key. | |
l0-l9 str Labels on function keys if not ``fn''. | |
LC bool (o) Lower-case only. | |
LE str (NP) Move cursor left n positions. | |
le str (P) Move cursor left one position. | |
li num Number of lines on screen or page (See BUGS section below) | |
ll str Last line, first column | |
lm num Lines of memory if > li (0 means varies). | |
ma str (o) Arrow key map (used by vi(1) version 2 only). | |
mb str Turn on blinking attribute. | |
md str Turn on bold (extra bright) attribute. | |
me str Turn off all attributes. | |
mh str Turn on half-bright attribute. | |
mi bool Safe to move while in insert mode. | |
mk str Turn on blank attribute (characters invisible). | |
ml str (o) Memory lock on above cursor. | |
mm str Turn on ``meta mode'' (8th bit). | |
mo str Turn off ``meta mode''. | |
mp str Turn on protected attribute. | |
mr str Turn on reverse-video attribute. | |
ms bool Safe to move in standout modes. | |
mu str (o) Memory unlock (turn off memory lock). | |
NC num Video attributes that can't be used with colors | |
nc bool (o) No correctly-working cr (Datamedia 2500, Hazeltine 2000). | |
nd str Non-destructive space (cursor right). | |
NL bool (o) | \n is newline, not line feed. |
nl str (o) Newline character if not \n. | |
ns bool (o) Terminal is a CRT but doesn't scroll. | |
nw str (P) Newline (behaves like cr followed by do). | |
OP bool (o) Odd parity. | |
oc str Set all colors to the original ones. | |
op str Set default color-pair to the original one. | |
os bool Terminal overstrikes. | |
pa num Maximum number of color-pairs on the screen. | |
pb num Lowest baud where delays are required. | |
pc str Pad character (default NUL). | |
pf str Turn off the printer. | |
pk str Program function key n to type string s (terminfo(5) only). | |
pl str Program function key n to execute string s (terminfo(5) only). | |
pO str (N) Turn on the printer for n bytes. | |
po str Turn on the printer. | |
ps str Print contents of the screen. | |
pt bool (o) Has hardware tabs (may need to be set with is). | |
px str Program function key n to transmit string s (terminfo(5) only). | |
r1-r3 str Reset terminal completely to sane modes (terminfo(5) only). | |
rc str (P) Restore cursor to position of last sc. | |
rf str Name of file containing reset codes. | |
RI str (NP) Move cursor right n positions. | |
rp str (NP*) Repeat character c n times. | |
rs str Reset terminal completely to sane modes (termcap only). | |
sa str (NP) Define the video attributes. | |
Sb str Set background color to #1. | |
sc str (P) Save cursor position. | |
se str End standout mode. | |
Sf str Set foreground color to #1. | |
SF str (NP*) Scroll forward n lines. | |
sf str (P) Scroll text up. | |
sg num Number of garbage chars left by so or se (default 0). | |
so str Begin standout mode. | |
SR str (NP*) Scroll backward n lines. | |
sr str (P) Scroll text down. | |
st str Set a tab in all rows, current column. | |
ta str (P) Tab to next 8-position hardware tab stop. | |
tc str Entry of similar terminal - must be last. | |
te str String to end programs that use . | |
ti str String to begin programs that use . | |
ts str (N) Go to status line, column n. | |
UC bool (o) Upper-case only. | |
uc str Underscore one character and move past it. | |
ue str End underscore mode. | |
ug num Number of garbage chars left by us or ue (default 0). | |
ul bool Underline character overstrikes. | |
UP str (NP*) Move cursor up n lines. | |
up str Upline (cursor up). | |
us str Start underscore mode. | |
ut bool Screen erased with background color. | |
vb str Visible bell (must not move cursor). | |
ve str Make cursor appear normal (undo vs/ vi). | |
vi str Make cursor invisible. | |
vs str Make cursor very visible. | |
vt num Virtual terminal number (not supported on all systems). | |
wi str (N) Set current window. | |
ws num Number of columns in status line. | |
xb bool Beehive
(f1=
ESC ,
f2=^C).
| |
xn bool Newline ignored after 80 cols (Concept). | |
xo bool Terminal uses xoff/xon
(
DC3 /
DC1 )
handshaking.
| |
xr bool (o) Return acts like ce cr nl (Delta Data). | |
xs bool Standout not erased by overwriting (Hewlett-Packard). | |
xt bool Tabs ruin, magic so char (Teleray 1061). | |
xx bool (o) Tektronix 4025 insert-line. | |
ZZ str Pointer to the extended termcap entry. See tgetent(3) for details. |
ca|concept100|c100|concept|c104|concept100-4p|HDS Concept-100:\
:al=3*\E^R:am:bl=^G:cd=16*\E^C:ce=16\E^U:cl=2*^L:cm=\Ea%+ %+ :\
:co#80:.cr=9^M:db:dc=16\E^A:dl=3*\E^B:do=^J:ei=\E\200:eo:im=\E^P:in:\
:ip=16*:is=\EU\Ef\E7\E5\E8\El\ENH\EK\E\200\Eo&\200\Eo\47\E:k1=\E5:\
:k2=\E6:k3=\E7:kb=^h:kd=\E<:ke=\Ex:kh=\E?:kl=\E>:kr=\E=:ks=\EX:\
:ku=\E;:le=^H:li#24:mb=\EC:me=\EN\200:mh=\EE:mi:mk=\EH:mp=\EI:\
:mr=\ED:nd=\E=:pb#9600:rp=0.2*\Er%.%+ :se=\Ed\Ee:sf=^J:so=\EE\ED:\
:.ta=8\t:te=\Ev \200\200\200\200\200\200\Ep\r\n:\
:ti=\EU\Ev 8p\Ep\r:ue=\Eg:ul:up=\E;:us=\EG:\
:vb=\Ek\200\200\200\200\200\200\200\200\200\200\200\200\200\200\EK:\
:ve=\Ew:vs=\EW:vt#8:xn:\
:bs:cr=^M:dC#9:dT#8:nl=^J:ta=^I:pt:
Entries may continue onto multiple lines by giving a \ as the last character of a line, and empty fields may be included for readability (here between the last field on a line and the first field on the next). Comments may be included on lines beginning with ``#''.
Numeric capabilities are followed by the character `#' then the value. In the example above co, which indicates the number of columns the display has, gives the value `80' for the Concept.
Finally, string-valued capabilities, such as ce (clear-to-end-of-line sequence) are given by the two-letter code, an `=', then a string ending at the next following `:'. A delay in milliseconds may appear after the `=' in such a capability, which causes padding characters to be supplied by tputs(3) after the remainder of the string is sent to provide this delay. The delay can be either a number, such as `20', or a number followed by an `*', such as `3*'. An `*' indicates that the padding required is proportional to the number of lines affected by the operation, and the amount given is the per-affected-line padding required. (In the case of insert-character, the factor is still the number of lines affected; this is always 1 unless the terminal has in and the software uses it.) When an `*' is specified, it is sometimes useful to give a delay of the form `3.5' to specify a delay per line to tenths of milliseconds. (Only one decimal place is allowed.)
A number of escape sequences are provided in the string-valued capabilities
for easy encoding of control characters there.
\E
maps to an
ESC
character,
^X
maps to a control-X for any appropriate X,
and the sequences
\n
\r
\t
\b
\f
map to linefeed, return, tab, backspace, and formfeed, respectively.
Finally, characters may be given as three octal digits after a
\,
and the characters
^
and
\
may be given as
\^
and
\\.
If it is necessary to place a
:
in a capability it must be escaped in
octal as
\072.
If it is necessary to place a
NUL
character in a string capability it
must be encoded as
\200.
(The routines that deal with
termcap
use C strings and strip the high bits of the output very late, so that
a
\200
comes out as a
\000
would.)
Sometimes individual capabilities must be commented out. To do this, put a period before the capability name. For example, see the first cr and ta in the example above.
.termcap
and programs will look there before looking in
/usr/share/misc/termcap
.
You can also set the environment variable
TERMPATH
to a list of absolute file pathnames (separated by spaces or colons),
one of which contains the description you are working on,
and programs will search them in the order listed, and nowhere else.
See
termcap(3).
The
TERMCAP
environment variable is usually set to the
termcap
entry itself
to avoid reading files when starting up a program.
To get the padding for insert-line right
(if the terminal manufacturer did not document it),
a severe test is to use
vi(1)
to edit
/etc/passwd
at 9600 baud, delete roughly 16 lines from the middle of the screen,
then hit the `u' key several times quickly.
If the display messes up, more padding is usually needed.
A similar test can be used for insert-character.
If there is a code (such as backspace) to move the cursor one position to the left, that capability should be given as le. Similarly, codes to move to the right, up, and down should be given as nd, up, and do, respectively. These local cursor motions should not alter the text they pass over; for example, you would not normally use ``nd= '' unless the terminal has the os capability, because the space would erase the character moved over.
A very important point here is that the local cursor motions encoded in termcap have undefined behavior at the left and top edges of a CRT display. Programs should never attempt to backspace around the left edge, unless bw is given, and never attempt to go up off the top using local cursor motions.
In order to scroll text up, a program goes to the bottom left corner of the screen and sends the sf (index) string. To scroll text down, a program goes to the top left corner of the screen and sends the sr (reverse index) string. The strings sf and sr have undefined behavior when not on their respective corners of the screen. Parameterized versions of the scrolling sequences are SF and SR, which have the same semantics as sf and sr except that they take one parameter and scroll that many lines. They also have undefined behavior except at the appropriate corner of the screen.
The am capability tells whether the cursor sticks at the right edge of the screen when text is output there, but this does not necessarily apply to nd from the last column. Leftward local motion is defined from the left edge only when bw is given; then an le from the left edge will move to the right edge of the previous row. This is useful for drawing a box around the edge of the screen, for example. If the terminal has switch-selectable automatic margins, the termcap description usually assumes that this feature is on, i.e., am. If the terminal has a command that moves to the first column of the next line, that command can be given as nw (newline). It is permissible for this to clear the remainder of the current line, so if the terminal has no correctly-working CR and LF it may still be possible to craft a working nw out of one or both of them.
These capabilities suffice to describe hardcopy and ``glass-tty'' terminals. Thus the Teletype model 33 is described as
T3|tty33|33|tty|Teletype model 33:\
:bl=^G:co#72:cr=^M:do=^J:hc:os:
and the Lear Siegler ADM-3 is described as
l3|adm3|3|LSI ADM-3:\
:am:bl=^G:cl=^Z:co#80:cr=^M:do=^J:le=^H:li#24:sf=^J:
The % encodings have the following meanings:
%% output `%' | |||||||||
%d output value as in printf(3) %d | |||||||||
%2 output value as in printf(3) %2d | |||||||||
%3 output value as in printf(3) %3d | |||||||||
%. output value as in printf(3) %c | |||||||||
%+x add
x
to value, then do %.
| %>xy | if
value >
x
then add
y,
no output
| %r reverse order of two parameters, no output
| %i increment by one, no output
| %n exclusive-or all parameters with 0140 (Datamedia 2500)
| %B | BCD (16*(value/10)) + (value%10), no output
| %D Reverse coding (value - 2*(value%16)), no output (Delta Data).
| |
Consider the Hewlett-Packard 2645, which, to get to row 3 and column 12, needs
to be sent
``\E&a12c03Y''
padded for 6 milliseconds.
Note that the order
of the row and column coordinates is reversed here
and that the row and column
are sent as two-digit integers.
Thus its
cm
capability is
``cm=6\E&%r%2c%2Y
''.
The Datamedia 2500 needs the current row and column sent encoded in binary using ``%.''. Terminals that use ``%.'' need to be able to backspace the cursor le(.blm Pp) and to move the cursor up one line on the screen up(.blm Pp.) This is necessary because it is not always safe to transmit \n, ^D, and \r, as the system may change or discard them. (Programs using termcap must set terminal modes so that tabs are not expanded, so \t is safe to send. This turns out to be essential for the Ann Arbor 4080.)
A final example is the Lear Siegler
ADM-3a,
which offsets row and column
by a blank character, thus
``cm=\E=%+
%+
''.
Row or column absolute cursor addressing can be given as single parameter capabilities ch (horizontal position absolute) and cv (vertical position absolute). Sometimes these are shorter than the more general two-parameter sequence (as with the Hewlett-Packard 2645) and can be used in preference to cm. If there are parameterized local motions (e.g., move n positions to the right) these can be given as DO, LE, RI, and UP with a single parameter indicating how many positions to move. These are primarily useful if the terminal does not have cm, such as the Tektronix 4025.
If the terminal has the ability to define a window as part of memory which all commands affect, it should be given as the parameterized string wi. The four parameters are the starting and ending lines in memory and the starting and ending columns in memory, in that order. (This terminfo(5) capability is described for completeness. It is unlikely that any Ns-using program will support it.)
If the terminal can retain display memory above the screen, then the da capability should be given; if display memory can be retained below, then db should be given. These indicate that deleting a line or scrolling may bring non-blank lines up from below or that scrolling back with sr may bring down non-blank lines.
abc def
''
using local
cursor motions (not spaces) between the
``abc''
and the
``def''.
Then position the cursor before the
``abc''
and put the terminal in insert
mode.
If typing characters causes the rest of the line to shift
rigidly and characters to fall off the end, then your terminal does
not distinguish between blanks and untyped positions.
If the
``abc''
shifts over to the
``def''
which then move together around the end of the
current line and onto the next as you insert, then you have the second type of
terminal and should give the capability
in,
which stands for
``insert null''.
While these are two logically separate attributes
(one-line vs. multi-line insert mode,
and special treatment of untyped spaces),
we have seen no terminals whose insert
mode cannot be described with the single attribute.
termcap can describe both terminals that have an insert mode and terminals that send a simple sequence to open a blank position on the current line. Give as im the sequence to get into insert mode. Give as ei the sequence to leave insert mode. Now give as ic any sequence that needs to be sent just before each character to be inserted. Most terminals with a true insert mode will not give ic; terminals that use a sequence to open a screen position should give it here. (If your terminal has both, insert mode is usually preferable to ic. Do not give both unless the terminal actually requires both to be used in combination.) If post-insert padding is needed, give this as a number of milliseconds in ip (a string option). Any other sequence that may need to be sent after insertion of a single character can also be given in ip. If your terminal needs to be placed into an `insert mode' and needs a special code preceding each inserted character, then both im/ ei and ic can be given, and both will be used. The IC capability, with one parameter n, will repeat the effects of ic n times.
It is occasionally necessary to move around while in insert mode to delete characters on the same line (e.g., if there is a tab after the insertion position). If your terminal allows motion while in insert mode, you can give the capability mi to speed up inserting in this case. Omitting mi will affect only speed. Some terminals (notably Datamedia's) must not have mi because of the way their insert mode works.
Finally, you can specify dc to delete a single character, DC with one parameter n to delete n characters, and delete mode by giving dm and ed to enter and exit delete mode (which is any mode the terminal needs to be placed in for dc to work).
Codes to begin underlining and end underlining can be given as us and ue, respectively. Underline mode change garbage is specified by ug, similar to sg. If the terminal has a code to underline the current character and move the cursor one position to the right, such as the Microterm Mime, this can be given as uc.
Other capabilities to enter various highlighting modes include mb (blinking), md (bold or extra bright), mh (dim or half-bright), mk (blanking or invisible text), mp (protected), mr (reverse video), me (turn off all attribute modes), as (enter alternative character set mode), and ae (exit alternative character set mode). Turning on any of these modes singly may or may not turn off other modes.
If there is a sequence to set arbitrary combinations of mode, this should be given as sa (set attributes), taking 9 parameters. Each parameter is either 0 or 1, as the corresponding attributes is on or off. The 9 parameters are, in order: standout, underline, reverse, blink, dim, bold, blank, protect, and alternative character set. Not all modes need be supported by sa, only those for which corresponding attribute commands exist. (It is unlikely that a Ns-using program will support this capability, which is defined for compatibility with terminfo(5)).
Terminals with the ``magic cookie'' glitches (sg and ug), rather than maintaining extra attribute bits for each character cell, instead deposit special ``cookies'', or ``garbage characters'', when they receive mode-setting sequences, which affect the display algorithm.
Some terminals, such as the Hewlett-Packard 2621, automatically leave standout mode when they move to a new line or when the cursor is addressed. Programs using standout mode should exit standout mode on such terminals before moving the cursor or sending a newline. On terminals where this is not a problem, the ms capability should be present to say that this overhead is unnecessary.
If the terminal has a way of flashing the screen to indicate an error quietly (a bell replacement), this can be given as vb; it must not move the cursor.
If the cursor needs to be made more visible than normal when it is not on the bottom line (to change, for example, a non-blinking underline into an easier-to-find block or blinking underline), give this sequence as vs. If there is a way to make the cursor completely invisible, give that as vi. The capability ve, which undoes the effects of both of these modes, should also be given.
If your terminal correctly displays underlined characters (with no special codes needed) even though it does not overstrike, then you should give the capability ul. If overstrikes are erasable with a blank, this should be indicated by giving eo.
The
ma
entry is also used to indicate arrow keys on terminals that have
single-character arrow keys.
It is obsolete but still in use in
version 2 of
vi
which must be run on some minicomputers due to
memory limitations.
This field is redundant with
kl,
kr,
ku,
kd,
and
kh.
It consists of groups of two characters.
In each group, the first character is what an arrow key sends, and the
second character is the corresponding
vi
command.
These commands are
h
for
kl,
j
for
kd,
k
for
ku,
l
for
kr,
and
H
for
kh.
For example, the Mime would have
``ma=^Hh^Kj^Zk^Xl
''
indicating arrow keys left (^H), down (^K), up (^Z), and right (^X).
(There is no home key on the Mime.)
Other capabilities include is, an initialization string for the terminal, and if, the name of a file containing long initialization strings. These strings are expected to set the terminal into modes consistent with the rest of the termcap description. They are normally sent to the terminal by the tset(1) program each time the user logs in. They will be printed in the following order: is; setting tabs using ct and st; and finally if. (terminfo(5) uses i1-i2 instead of is and runs the program iP and prints i3 after the other initializations.) A pair of sequences that does a harder reset from a totally unknown state can be analogously given as rs and if. These strings are output by the reset(1) program, which is used when the terminal gets into a wedged state. (terminfo(5) uses r1-r3 instead of rs.) Commands are normally placed in rs and rf only if they produce annoying effects on the screen and are not necessary when logging in. For example, the command to set the VT100 into 80-column mode would normally be part of is, but it causes an annoying glitch of the screen and is not normally needed since the terminal is usually already in 80-column mode.
If the terminal has hardware tabs, the command to advance to the next tab stop can be given as ta (usually ^I). A ``backtab'' command which moves leftward to the previous tab stop can be given as bt. By convention, if the terminal driver modes indicate that tab stops are being expanded by the computer rather than being sent to the terminal, programs should not use ta or bt even if they are present, since the user may not have the tab stops properly set. If the terminal has hardware tabs that are initially set every n positions when the terminal is powered up, then the numeric parameter it is given, showing the number of positions between tab stops. This is normally used by the tset(1) command to determine whether to set the driver mode for hardware tab expansion, and whether to set the tab stops. If the terminal has tab stops that can be saved in nonvolatile memory, the termcap description can assume that they are properly set.
If there are commands to set and clear tab stops, they can be given as ct (clear all tab stops) and st (set a tab stop in the current column of every row). If a more complex sequence is needed to set the tabs than can be described by this, the sequence can be placed in is or if.
NUL
(zero) character as a pad,
this can be given as
pc.
Only the first character of the
pc
string is used.
If the terminal has commands to save and restore the position of the cursor, give them as sc and rc.
If the terminal has an extra ``status line'' that is not normally used by software, this fact can be indicated. If the status line is viewed as an extra line below the bottom line, then the capability hs should be given. Special strings to go to a position in the status line and to return from the status line can be given as ts and fs. (fs must leave the cursor position in the same place that it was before ts. If necessary, the sc and rc strings can be included in ts and fs to get this effect.) The capability ts takes one parameter, which is the column number of the status line to which the cursor is to be moved. If escape sequences and other special commands such as tab work while in the status line, the flag es can be given. A string that turns off the status line (or otherwise erases its contents) should be given as ds. The status line is normally assumed to be the same width as the rest of the screen, i.e., co. If the status line is a different width (possibly because the terminal does not allow an entire line to be loaded), then its width in columns can be indicated with the numeric parameter ws.
If the terminal can move up or down half a line, this can be indicated with hu (half-line up) and hd (half-line down). This is primarily useful for superscripts and subscripts on hardcopy terminals. If a hardcopy terminal can eject to the next page (form feed), give this as ff (usually ^L).
If there is a command to repeat a given character a given number of times (to save time transmitting a large number of identical characters), this can be indicated with the parameterized string rp. The first parameter is the character to be repeated and the second is the number of times to repeat it. (This is a terminfo(5) feature that is unlikely to be supported by a program that uses .)
If the terminal has a settable command character, such as the
Tektronix 4025, this can be indicated with
CC.
A prototype command character is chosen which is used in all capabilities.
This character is given in the
CC
capability to identify it.
The following convention is supported on some
UNIX
systems:
The environment is to be searched for a
CC
variable,
and if found,
all occurrences of the prototype character are replaced by the character
in the environment variable.
This use of the
CC
environment variable
is a very bad idea, as it conflicts with
make(1).
Terminal descriptions that do not represent a specific kind of known terminal, such as switch, dialup, patch, and network, should include the gn (generic) capability so that programs can complain that they do not know how to talk to the terminal. (This capability does not apply to virtual terminal descriptions for which the escape sequences are known.)
If the terminal uses xoff/xon (DC3/DC1) handshaking for flow control, give xo. Padding information should still be included so that routines can make better decisions about costs, but actual pad characters will not be transmitted.
If the terminal has a ``meta key'' which acts as a shift key, setting the 8th bit of any character transmitted, then this fact can be indicated with km. Otherwise, software will assume that the 8th bit is parity and it will usually be cleared. If strings exist to turn this ``meta mode'' on and off, they can be given as mm and mo.
If the terminal has more lines of memory than will fit on the screen at once, the number of lines of memory can be indicated with lm. An explicit value of 0 indicates that the number of lines is not fixed, but that there is still more memory than fits on the screen.
If the terminal is one of those supported by the UNIX system virtual terminal protocol, the terminal number can be given as vt.
Media copy strings which control an auxiliary printer connected to the terminal can be given as ps: print the contents of the screen; pf: turn off the printer; and po: turn on the printer. When the printer is on, all text sent to the terminal will be sent to the printer. It is undefined whether the text is also displayed on the terminal screen when the printer is on. A variation pO takes one parameter and leaves the printer on for as many characters as the value of the parameter, then turns the printer off. The parameter should not exceed 255. All text, including pf, is transparently passed to the printer while pO is in effect.
Strings to program function keys can be given as pk, pl, and px. Each of these strings takes two parameters: the function key number to program (from 0 to 9) and the string to program it with. Function key numbers out of this range may program undefined keys in a terminal-dependent manner. The differences among the capabilities are that pk causes pressing the given key to be the same as the user typing the given string; pl causes the string to be executed by the terminal in local mode; and px causes the string to be transmitted to the computer. Unfortunately, due to lack of a definition for string parameters in , only terminfo(5) supports these capabilities. The ZZ capability is automatically generated in the tgetent call and must never be defined in termcap entries.
The nc capability, now obsolete, formerly indicated Datamedia terminals, which echo \r \n for carriage return then ignore a following linefeed.
Terminals that ignore a linefeed immediately after an am wrap, such as the Concept, should indicate xn.
If ce is required to get rid of standout (instead of merely writing normal text on top of it), xs should be given.
Teleray terminals, where tabs turn all characters moved over to blanks, should indicate xt (destructive tabs). This glitch is also taken to mean that it is not possible to position the cursor on top of a magic cookie, and that to erase standout mode it is necessary to use delete and insert line.
The Beehive Superbee, which is unable to correctly transmit the
ESC
or
^C
characters, has
xb,
indicating that the
``f1''
key is used for
ESC
and
``f2''
for ^C.
(Only certain Superbees have this problem, depending on the
ROM.)
Other specific terminal problems may be corrected by adding more capabilities of the form x x.
hn|2621-nl:ks@:ke@:tc=2621:
defines a ``2621-nl'' that does not have the ks or ke capabilities, hence does not turn on the function key labels when in visual mode. This is useful for different modes for a terminal, or for different user preferences.
/usr/share/misc/termcap
/usr/share/misc/termcap.db
AT&T
System V UNIX
Release 2.0.
The transition will be relatively painless if capabilities flagged as
``obsolete''
are avoided.
Lines and columns are now stored by the kernel as well as in the termcap entry. Most programs now use the kernel information primarily; the information in this file is used only if the kernel does not have any information.
Not all programs support all entries.