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NAME    [Toc]    [Back]

     termcap - terminal capability database

SYNOPSIS    [Toc]    [Back]


DESCRIPTION    [Toc]    [Back]

     The termcap file is a database describing  terminals,  used,
for example,
     by  vi(1) and curses(3).  Terminals are described in termcap
by giving a
     set of capabilities that they have and by describing how operations are
     performed.   Padding  requirements  and  initialization  sequences are included
 in termcap.

     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
     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

     The following suffixes should be used where possible:

     Suffix                                               Meaning

Example    [Toc]    [Back]

     -w          Wide    mode    (more    than    80    columns).
     -am         With   automatic   margins   (usually  default).
     -nam              Without         automatic         margins.
     -n             Number      of      lines      on     screen.
     -na       No arrow keys (leave them in local).          concept100-na
     -np       Number of pages of memory.                    concept100-4p
     -rv       Reverse video.                                concept100-rv

CAPABILITIES    [Toc]    [Back]

     The characters in the Notes function field in the table have
the following
 meanings (more than one may apply to a capability):

     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.

     Name      Type      Notes     Description
     ae        str       (P)       End alternate character set.
     AL        str       (NP*)     Add n new blank lines
     al        str       (P*)      Add new blank line.
     am         bool                 Terminal  has automatic margins.
     as        str       (P)       Start alternate character set.
     bc        str       (o)       Backspace if not ^H.
     bl        str       (P)       Audible signal (bell).
     bs         bool       (o)        Terminal can backspace with
     bt        str       (P)       Back tab.
     bw        bool                le (backspace) wraps from column 0 to last
     CC          str                  Terminal  settable  command
character in
     cd        str       (P*)      Clear to end of display.
     ce        str       (P)       Clear to end of line.
     ch        str       (NP)      Set cursor column  (horizontal
     cl         str       (P*)      Clear screen and home cursor.
     CM        str        (NP)       Memory-relative  cursor  addressing.
     cm        str       (NP)      Screen-relative cursor motion.
     co        num                 Number of columns  in  a  line
(see BUGS section
     cr        str       (P)       Carriage return.
     cs          str         (NP)       Change  scrolling  region
     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 bs  delay  needed
(default 0).
     db         bool                Display may be retained below
the screen.
     DC        str       (NP*)     Delete n characters.
     dC        num       (o)       Milliseconds cr  delay  needed
(default 0).
     dc        str       (P*)      Delete character.
     dF         num        (o)       Milliseconds 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 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).
     ec        str       (NP)      Erase n characters.
     ed        str                 End delete mode.
     ei        str                 End insert mode.
     eo         bool                 Can erase overstrikes with a
     EP        bool      (o)       Even parity.
     es        bool                Escape can be used on the status line.
     ff         str       (P*)      Hardcopy terminal page eject.
     fs        str                 Return from status line.
     gn        bool                Generic line type, for example
     hc        bool                Hardcopy terminal.
     HD        bool      (o)       Half-duplex.
     hd         str                  Half-line  down (forward 1/2
     ho        str       (P)       Home cursor.
     hs        bool                Has extra ``status line''.
     hu         str                  Half-line  up  (reverse  1/2
     hz         bool                 Cannot  print  ``~'' (Hazeltine).
     i1-i3       str                   Terminal    initialization
strings (terminfo
     IC        str       (NP*)     Insert n blank characters.
     ic        str       (P*)      Insert character.
     if         str                  Name of file containing initialization
     im        str                 Enter insert mode.
     in         bool                 Insert  mode   distinguishes
     iP         str                  Pathname of program for initialization
                                   (terminfo 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.
     kA        str                 Sent by insert-line key.
     ka        str                 Sent by clear-all-tabs key.
     kb        str                 Sent by backspace key.
     kC         str                 Sent by clear-screen or erase
     kD        str                 Sent by delete-character  key.
     kd        str                 Sent by down-arrow key.
     kE         str                  Sent by clear-to-end-of-line
     ke        str                  Out  of  ``keypad  transmit''
     kF         str                  Sent  by scroll-forward/down
     kH        str                 Sent by home-down key.
     kh        str                 Sent by home key.
     kI        str                 Sent  by  insert-character  or
     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        bool                Has  a  ``meta''  key  (shift,
sets parity
     kN        str                 Sent by next-page key.
     kn         num        (o)        Number  of function (k0-k9)
keys (default
     ko        str       (o)       Termcap entries for other nonfunction
     kP        str                 Sent by previous-page key.
     kR         str                  Sent  by  scroll-backward/up
     kr        str                 Sent by right-arrow key.
     kS        str                 Sent by clear-to-end-of-screen
     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
     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 version 2 only).
     mb        str                 Turn on blinking attribute.
     md        str                 Turn on  bold  (extra  bright)
     me        str                 Turn off all attributes.
     mh        str                 Turn on half-bright attribute.
     mi        bool                Safe to move while  in  insert
     mk        str                 Turn on blank attribute (characters
     ml        str       (o)       Memory lock on above cursor.
     mm        str                 Turn  on  ``meta  mode''  (8th
     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
     mu        str       (o)       Memory unlock (turn off memory
     nc        bool      (o)       No correctly-working cr (Datamedia 2500,
                                   Hazeltine 2000).
     nd         str                 Non-destructive space (cursor
     NL        bool      (o)      n is newline, not line feed.
     nl        str       (o)       Newline character if notn.
     ns        bool      (o)       Terminal is a CRT but  doesn't
     nw         str       (P)       Newline (behaves like cr followed by do).
     OP        bool      (o)       Odd parity.
     os        bool                Terminal overstrikes.
     pb        num                 Lowest baud where  delays  are
     pc         str                 Pad character (default NUL ).
     pf        str                 Turn off the printer.
     pk        str                 Program function key n to type
string s
                                   (terminfo only).
     pl        str                 Program function key n to execute string s
                                   (terminfo only).
     pO        str       (N)       Turn  on  the  printer  for  n
     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
     px         str                  Program  function  key  n to
transmit string s
                                   (terminfo only).
     r1-r3     str                 Reset terminal  completely  to
sane modes
                                   (terminfo only).
     rc         str       (P)       Restore cursor to position of
last sc.
     rf        str                 Name of file containing  reset
     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.
     sc        str       (P)       Save cursor position.
     se        str                 End standout mode.
     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
     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 termcap.
     ti        str                 String to begin programs  that
use termcap.
     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.
     vb        str                 Visible bell  (must  not  move
     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
     xb        bool                Beehive (f1= ESC, f2=^C).
     xn         bool                 Newline  ignored  after   80
columns (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
     xt        bool                Tabs ruin, magic so char (Teleray 1061).
     xx        bool      (o)       Tektronix 4025 insert-line.

   A Sample Entry    [Toc]    [Back]
     The  following  entry,  which  describes the Concept-100, is
among the more
     complex entries in the termcap file as of this writing.

     ca|concept100|c100|concept|c104|concept100-4p|HDS       Concept-100:
:al=3*R:am:bl=^G:cd=16*C:ce=16U:cl=2*^L:cm=%+        %+         :
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 `#'.

   Types of Capabilities    [Toc]    [Back]
     Capabilities in termcap are of three types: Boolean capabilities, which
     indicate particular features that the terminal has;  numeric
     giving  the  size  of  the  display or the size of other attributes; and
     string capabilities, which give character sequences that can
be used to
     perform  particular  terminal  operations.  All capabilities
have two-letter
     codes.   For  instance,  the  fact  that  the  Concept   has
automatic margins (an
     automatic  return  and  linefeed  when  the end of a line is
reached) is indicated
 by the Boolean capability am.  Hence  the  description
of the Concept
     includes am.

     Boolean  capabilities  are  defined by their name, fo.  They
have no argument.
  The presence of a boolean capability  name  sets  its
value to true.
     A capability value will be reverted to false, by appending a
@ char after
     the name, such as fo@.

     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-toend-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 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 se-     tbf map to  linefeed,  return,  tab,  backspace,  and
  respectively.   Finally,  characters  may be given as
three octal digits
 after a and the characters ^ and may be given as^  and .
     it  is necessary to place a : in a capability it must be escaped in octal
     as072.  If it is necessary to place a  NUL  character  in  a
string capability
  it  must  be encoded as200.  (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 a000 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.

   Preparing Descriptions    [Toc]    [Back]
     The  most effective way to prepare a terminal description is
by imitating
     the description of a similar  terminal  in  termcap  and  to
build up a description
  gradually,  using partial descriptions with vi to
check that
     they are correct.  Be aware that a very unusual terminal may
expose deficiencies
  in  the ability of the termcap file to describe it
or bugs in vi.
     To easily test a new terminal description you are working on
you can put
     it in your home directory in a file called .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
     (separated by spaces or colons), one of which  contains  the
     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
     did  not  document  it),  a severe test is to use vi 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

   Basic Capabilities    [Toc]    [Back]
     The  number  of columns on each line of the display is given
by the co numeric
 capability.  If the display is a CRT, then the  number
of lines on
     the  screen  is  given by the li capability.  If the display
wraps around to
     the beginning of the next line when the cursor  reaches  the
right margin,
     then  it should have the am capability.  If the terminal can
clear its
     screen, the code to do this is given by the cl string  capability.  If the
     terminal overstrikes (rather than clearing the position when
a character
     is overwritten), it should have the os capability.   If  the
terminal is a
     printing  terminal,  with no soft copy unit, give it both hc
and os.  (os
     applies to storage scope terminals, such  as  the  Tektronix
4010 series, as
     well as to hard copy and APL terminals.)  If there is a code
to move the
     cursor to the left edge of the current row, give this as cr.
     this  will  be  carriage-return,  ^M.) If there is a code to
produce an audible
 signal (bell, beep, etc.), give this as bl.

     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

     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 switchselectable
 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 ``glasstty'' terminals.
  Thus the Teletype model 33 is described as

           T3|tty33|33|tty|Teletype           model           33:

     and the Lear Siegler ADM-3 is described as

           l3|adm3|3|LSI                                   ADM-3:

   Parameterized Strings    [Toc]    [Back]
     Cursor addressing and other strings requiring parameters are
described by
     a parameterized string capability, with  printf(3)-like  escapes %x in it,
     while  other  characters  are passed through unchanged.  For
example, to address
 the cursor the cm capability is given, using  two  parameters: the
     row  and  column to move to.  (Rows and columns are numbered
from zero and
     refer to the physical screen visible to the user, not to any
unseen memory.
   If the terminal has memory-relative cursor addressing,
that can be
     indicated by an analogous CM capability.)

     The % encodings have the following meanings:

     %%       output `%'
     %d       output value as in printf %d
     %2       output value as in printf %2d
     %3       output value as in printf %3d
     %.       output value as in printf %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
     %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  ``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

     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) and to move the cursor up one  line  on  the
screen (up).
     This  is necessary because it is not always safe to transmitn, ^D, asdthe system may change or discard them.  (Programs  using

     must set terminal modes so that tabs are not expanded, st is
safe to
     send.  This turns out to be  essential  for  the  Ann  Arbor

     A  final  example  is the Lear Siegler ADM-3a, which offsets
row and column
     by a blank character, thus ``cm==%+ %+ ''.

     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

   Cursor Motions    [Toc]    [Back]
     If the terminal has a fast way to home the  cursor  (to  the
very upper left
     corner  of the screen), this can be given as ho.  Similarly,
a fast way of
     getting to the lower left-hand corner can be  given  as  ll;
this may involve
 going up with up from the home position, but a program
should never
     do this itself (unless ll does), because it can make no  assumption about
     the  effect  of moving up from the home position.  Note that
the home position
 is the same as cursor address (0,0): to  the  top  left
corner of the
     screen,  not  of  memory.   (Therefore,  the  `` sequence on
 terminals cannot be used for ho.)

   Area Clears    [Toc]    [Back]
     If the terminal can clear from the current position  to  the
end of the
     line,  leaving  the cursor where it is, this should be given
as ce.  If the
     terminal can clear from the current position to the  end  of
the display,
     this  should  be  given as cd.  cd must only be invoked from
the first column
 of a line.  (Therefore, it can be simulated by a request
to delete a
     large number of lines, if a true cd is not available.)

   Insert/Delete Line
     If  the  terminal  can open a new blank line before the line
containing the
     cursor, this should be given as al; this must be invoked only from the
     first  position  of  a line.  The cursor must then appear at
the left of the
     newly blank line.  If the terminal can delete the line  that
the cursor is
     on,  this should be given as dl; this must only be used from
the first position
 on the line to be deleted.  Versions  of  al  and  dl
which take a
     single parameter and insert or delete that many lines can be
given as AL
     and DL.  If the terminal has  a  settable  scrolling  region
(like the
     VT100), the command to set this can be described with the cs
     which takes two parameters: the top and bottom lines of  the
scrolling region.
   The  cursor position is, alas, undefined after using
this command.
     It is possible to get the effect of insert  or  delete  line
using this command
 -- the sc and rc (save and restore cursor) commands are
also useful.
     Inserting lines at the top or bottom of the screen can  also
be done using
     sr  or  sf  on  many  terminals without a true insert/delete
line, and is often
 faster even on terminals with those features.

     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
     capability is described for completeness.   It  is  unlikely
that any
     termcap- 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.

   Insert/Delete Character
     There  are two basic kinds of intelligent terminals with respect to insert/delete
 character that can be described  using  termcap.
The most common
 insert/delete character operations affect only the characters on the
     current line and shift characters off the end  of  the  line
rigidly.  Other
     terminals, such as the Concept-100 and the Perkin Elmer Owl,
make a distinction
 between typed and untyped  blanks  on  the  screen,
shifting upon an
     insert  or  delete  only  to  an untyped blank on the screen
which is either
     eliminated or expanded to two untyped blanks.  You  can  determine the kind
     of terminal you have by clearing the screen then typing text
separated by
     cursor motions.  Type ``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
     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
     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).

   Highlighting, Underlining, and Visible Bells
     If  your  terminal  has  one  or  more  kinds of display attributes, these can
     be represented in a number of different  ways.   You  should
choose one display
  form  as  standout mode, representing a good high-contrast, easy-onthe-eyes
 format for highlighting error  messages  and  other
attention getters.
  (If you have a choice, reverse video plus half-bright
is good, or
     reverse video alone.)   The  sequences  to  enter  and  exit
standout mode are
     given as so and se, respectively.  If the code to change into or out of
     standout mode leaves one or even two blank spaces or garbage
     on  the  screen, as the TVI 912 and Teleray 1061 do, then sg
should be given
 to tell how many characters are left.

     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 alternate character set mode), and
ae (exit alternate
 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 alternate character set.  Not all modes
need be supported
 by sa, only those for which  corresponding  attribute
commands exist.
  (It is unlikely that a termcap-using program will support this capability,
 which is defined for compatibility with terminfo.)

     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 modesetting
 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
     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.

   Keypad    [Toc]    [Back]
     If  the  terminal has a keypad that transmits codes when the
keys are
     pressed, this information can be given.  Note that it is not
possible to
     handle  terminals  where the keypad only works in local mode
(this applies,
     for example, to the unshifted  Hewlett-Packard  2621  keys).
If the keypad
     can  be set to transmit or not transmit, give these codes as
ks and ke.
     Otherwise the keypad is assumed  to  always  transmit.   The
codes sent by
     the  left-arrow, right-arrow, up-arrow, down-arrow, and home
keys can be
     given as kl, kr, ku, kd, and kh, respectively.  If there are
     keys  such  as  f0,  f1, ..., f9, the codes they send can be
given as k0, k1,
     k9.  If these keys have labels other  than  the  default  f0
through f9, the
     labels can be given as l0, l1, l9.  The codes transmitted by
certain other
  special  keys  can  be  given:  kH   (home   down),   kb
(backspace), ka (clear
     all tabs), kt (clear the tab stop in this column), kC (clear
screen or
     erase), kD (delete character), kL (delete  line),  kM  (exit
insert mode),
     kE  (clear  to end of line), kS (clear to end of screen), kI
(insert character
 or enter insert mode),  kA  (insert  line),  kN  (next
page), kP (previous
  page),  kF  (scroll  forward/down),  kR  (scroll  backward/up), and kT (set
     a tab stop in this column).  In addition, if the keypad  has
a 3 by 3 array
  of  keys  including the four arrow keys, then the other
five keys can
     be given as K1, K2, K3, K4, and K5.  These keys  are  useful
when the effects
  of a 3 by 3 directional pad are needed.  The obsolete
ko capability
     formerly used to describe ``other'' function keys  has  been
     supplanted by the above capabilities.

     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.)

   Tabs and Initialization    [Toc]    [Back]
     If the terminal needs to be in a special mode when running a
program that
     uses  these  capabilities,  the codes to enter and exit this
mode can be
     given as ti and te.  This arises, for example,  from  terminals like the
     Concept  with more than one page of memory.  If the terminal
has only memory-relative
 cursor addressing and not screen-relative  cursor addressing,
     a  screen-sized  window  must  be fixed into the display for
cursor addressing
 to work properly.  This is also used for  the  Tektronix
4025, where ti
     sets the command character to be the one used by termcap.

     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 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  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 program, which is used
when the
     terminal gets into a wedged state.  (Terminfo 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 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

   Delays    [Toc]    [Back]
     Certain capabilities control padding in the terminal driver.
These are
     primarily  needed  by hardcopy terminals and are used by the
tset program
     to set terminal driver modes appropriately.  Delays embedded
in the capabilities
  cr,  sf, le, ff, and ta will cause the appropriate
delay bits to
     be set in the terminal driver.  If pb (padding baud rate) is
given, these
     values  can  be ignored at baud rates below the value of pb.
For 4.2BSD
     tset, the delays are given as numeric capabilities  dC,  dN,
dB, dF, and dT

   Miscellaneous    [Toc]    [Back]
     If  the  terminal requires other than a 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
     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
     with hu (half-line up) and hd  (half-line  down).   This  is
primarily useful
     for superscripts and subscripts on hardcopy terminals.  If a
     terminal can eject to the next page (form feed),  give  this
as ff (usually

     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 feature that is unlikely to
be supported
     by a program that uses termcap.)

     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

     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

     If the terminal uses xoff/xon (DC3/DC1) handshaking for flow
     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
     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

     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  terminaldependent 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 termcap,
only terminfo
     supports these capabilities.

   Glitches and Braindamage    [Toc]    [Back]
     Hazeltine terminals, which do not allow `~' characters to be
     should indicate hz.

     The  nc capability, now obsolete, formerly indicated Datamedia terminals,rn for carriage  return  then  ignore  a  following
     which echo

     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

     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.

   Similar Terminals    [Toc]    [Back]
     If  there are two very similar terminals, one can be defined
as being just
     like the other with certain exceptions.  The string capability tc can be
     given with the name of the similar terminal.  This capability must be
     last, and the combined length of the entries must not exceed
1024.  The
     capabilities  given before tc override those in the terminal
type invoked
     by tc.  A capability can be cancelled by placing xx@ to  the
left of the
     tc invocation, where xx is the capability.  For example, the


     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.

FILES    [Toc]    [Back]

     /usr/share/misc/termcap      File  containing  terminal  descriptions.
     /usr/share/misc/termcap.db  Hash  database  file  containing
terminal descriptions
 (see cap_mkdb(1)).

SEE ALSO    [Toc]    [Back]

     cap_mkdb(1),  ex(1),  more(1),  tset(1), ul(1), vi(1), curses(3), printf(3),
     termcap(3), term(7)

HISTORY    [Toc]    [Back]

     The termcap file format appeared in 3BSD.

CAVEATS AND BUGS    [Toc]    [Back]

     The Note: termcap functions were  replaced  by  terminfo  in
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.

     Vi  allows  only 256 characters for string capabilities, and
the routines
     in termcap(3) do not check for overflow of this buffer.  The
total length
     of  a single entry (excluding only escaped newlines) may not
exceed 1024.

     Not all programs support all entries.

OpenBSD     3.6                           March      6,      1993
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