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TERMCAP(5)		      File Formats Manual		    TERMCAP(5)

       termcap - terminal capability data base


       Termcap	is  a data base	describing terminals, used, e.g., by vi(1) and
       curses(3X).  Terminals are described in termcap by giving a set of  ca-
       pabilities  that	 they  have  and by describing how operations are per-
       formed.	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 is always two
       characters long and is used by older systems which store	 the  terminal
       type  in	 a  16-bit  word  in a system-wide data	base.  The second 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  first  and last should be in lower case and	contain	no blanks; the
       last name may well contain upper	case and blanks	for readability.

       Terminal	names (except for the last, verbose entry)  should  be	chosen
       using the following conventions.	 The particular	piece of hardware mak-
       ing 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 the 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

       The characters in the Notes field in the	table have the following mean-
       ings (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	 soft-
       ware 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 ^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
       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	  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)
       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
       ff    str   (P*)	  Hardcopy terminal page eject
       fs    str	  Return from status line
       gn    bool	  Generic line type (e.g. dialup, switch)
       hc    bool	  Hardcopy terminal
       HD    bool  (o)	  Half-duplex
       hd    str	  Half-line down (forward 1/2 linefeed)
       ho    str   (P)	  Home cursor
       hs    bool	  Has extra "status line"
       hu    str	  Half-line up (reverse	1/2 linefeed)
       hz    bool	  Cannot print ~s (Hazeltine)
       i1-i3 str	  Terminal initialization strings (terminfo only)
       IC    str   (NP*)  Insert n blank characters
       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	  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 upper right
       K3    str	  Sent by keypad center
       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	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    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 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	attibute
       ms    bool	  Safe to move in standout modes
       mu    str   (o)	  Memory unlock	(turn off memory lock)
       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
       os    bool	  Terminal overstrikes
       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 only)
       pl    str	  Program function key n to execute string s (terminfo 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	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	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
       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 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 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 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

       A Sample	Entry

       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*\E^R:am:bl=^G:cd=16*\E^C:ce=16\E^U:cl=2*^L:cm=\Ea%+ %+ :\^M:db:dc=16\E^A:dl=3*\E^B:do=^J:ei=\E\200:eo:im=\E^P:in:\
	       :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:\

       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	"#".

       Types of	Capabilities

       Capabilities in termcap are of three types: Boolean capabilities, which
       indicate	particular features that the terminal has;  numeric  capabili-
       ties,  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	 auto-
       matic margins (i.e., 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.

       Numeric	capabilities are followed by the character `#' then the	value.
       In the example above co,	which indicates	the number of columns the dis-
       play 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  end-
       ing  at the next	following `:'.	A delay	in milliseconds	may appear af-
       ter 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, e.g.  `20', or a	number
       followed	 by an `*', i.e., `3*'.	 An `*'	indicates that the padding re-
       quired is proportional to the number of lines affected  by  the	opera-
       tion,  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 capabil-
       ities 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-
       quences	\n  \r	\t  \b \f map to linefeed, return, tab,	backspace, and
       formfeed, respectively.	Finally, characters may	be given as three  oc-
       tal 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.

       Preparing Descriptions

       We now outline how to prepare descriptions of terminals.	 The most  ef-
       fective	way  to	prepare	a terminal description is by imitating the de-
       scription of a similar terminal in termcap and to build up  a  descrip-
       tion  gradually,	 using partial descriptions with vi to check that they
       are correct.  Be	aware that a very unusual terminal  may	 expose	 defi-
       ciencies	 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 pro-
       grams will look there before looking in /etc/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(3X).  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	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-char-

       Basic Capabilities

       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 ca-
       pability.   If the terminal overstrikes (rather than clearing the posi-
       tion when a character is	overwritten), it should	have the  os  capabil-
       ity.   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	termi-
       nals.)  If there	is a code to move the cursor to	the left edge  of  the
       current	row, give this as cr.  (Normally 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 dis-
       play.  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 (re-
       verse index) string.  The strings sf and	 sr  have  undefined  behavior
       when not	on their respective corners of the screen.  Parameterized ver-
       sions of	the scrolling sequences	are SF and SR, which have the same se-
       mantics	as  sf	and  sr	except that they take one parameter and	scroll
       that many lines.	 They also have	undefined behavior except at  the  ap-
       propriate 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 ap-
       ply  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  com-
       mand  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  re-
       mainder	of the current line, so	if the terminal	has no correctly-work-
       ing 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"	termi-
       nals.  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

       Cursor addressing and other strings requiring parameters	are  described
       by  a  parameterized string capability, with printf(3S)-like escapes %x
       in it, while other characters are passed	through	unchanged.  For	 exam-
       ple, to address the cursor the cm capability is given, using two	param-
       eters: 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 address-
       ing, 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 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	 capa-
       bility is "cm=6\E&%r%2c%2Y".

       The Datamedia 2500 needs	the current row	and column sent	encoded	in bi-
       nary 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 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 col-
       umn by a	blank character, thus "cm=\E=%+	%+ ".

       Row or column absolute cursor addressing	can be given as	single parame-
       ter capabilities	ch (horizontal position	absolute) and cv (vertical po-
       sition 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.

       Cursor Motions

       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 "\EH" se-
       quence on Hewlett-Packard terminals cannot be used for ho.)

       Area Clears

       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 dis-
       play,  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
       capability, 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) com-
       mands 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

       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 un-
       likely 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  in-
       sert/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	deter-
       mine 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

       Termcap can describe both terminals that	have an	insert mode and	termi-
       nals that send a	simple sequence	to open	a blank	position on  the  cur-
       rent  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 ter-
       minals 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 ter-
       minal has both, insert mode is usually preferable to ic.	 Do  not  give
       both  unless the	terminal actually requires both	to be used in combina-
       tion.)  If post-insert padding is needed, give this as a	number of mil-
       liseconds 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 pa-
       rameter 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

       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-
       on-the-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	stand-
       out  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	characters  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  pa-
       rameter 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 sup-
       port this capability, which is  defined	for  compatibility  with  ter-

       Terminals  with	the  "magic  cookie" glitches (sg and ug), rather than
       maintaining extra attribute bits	for each character cell,  instead  de-
       posit  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 ad-
       dressed.	 Programs using	standout mode should  exit  standout  mode  on
       such  terminals before moving the cursor	or sending a newline.  On ter-
       minals 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 spe-
       cial  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.


       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 ap-
       plies, 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  function  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  charac-
       ter),  kL  (delete  line),  kM  (exit insert mode), kE (clear to	end of
       line), kS (clear	to end of screen), kI (insert character	or  enter  in-
       sert  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 completely 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 ver-
       sion 2 of vi which must be run on some minicomputers due	to memory lim-
       itations.   This	 field	is  redundant with kl, kr, ku, kd, and kh.  It
       consists	of groups of two characters.  In each group, the first charac-
       ter  is what an arrow key sends,	and the	second character is the	corre-
       sponding	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

       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 Tek-
       tronix 4025, where ti sets the command character	to be the one used  by

       Other  capabilities include is, an initialization string	for the	termi-
       nal, 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 pro-
       gram iP and prints i3 after the other initializations.)	A pair of  se-
       quences	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 conven-
       tion, if	the terminal driver modes indicate that	tab  stops  are	 being
       expanded	 by  the computer rather than being sent to the	terminal, pro-
       grams 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 pow-
       ered  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 if.


       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 ca-
       pabilities 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 instead.


       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

       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	neces-
       sary,  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 es-
       cape 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  (possi-
       bly  because  the terminal does not allow an entire line	to be loaded),
       then its	width in columns can be	indicated with the  numeric  parameter

       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 use-
       ful  for	superscripts and subscripts on hardcopy	terminals.  If a hard-
       copy 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  charac-
       ters),  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 un-
       likely 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 sup-
       ported 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 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 ex-
       plicit 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 unde-
       fined 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 ef-

       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  pro-
       gram  (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-de-
       pendent	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

       Hazeltine terminals, which do not allow `~' characters to be displayed,
       should indicate hz.

       The  nc	capability,  now obsolete, formerly indicated Datamedia	termi-
       nals, which echo	\r \n for carriage  return  then  ignore  a  following

       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	 capa-
       bilities	of the form xx.

       Similar Terminals

       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	canceled by placing xx@	to the
       left  of	 the  tc invocation, where xx is the capability.  For example,
       the entry


       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	 pref-

       William Joy
       Mark Horton added underlining and keypad	support

       /etc/termcap   file containing terminal descriptions

       ex(1),  more(1),	 tset(1),  ul(1), vi(1), curses(3X), printf(3S), term-
       cap(3X),	term(7)

       Note: termcap was replaced by terminfo in UNIX System  V	 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	 term-
       cap entry.  Most	programs now use the kernel information	primarily; the
       information in this file	is used	only if	the kernel does	not  have  any

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

       Not all programs	support	all entries.

3rd Berkeley Distribution	 June 23, 1990			    TERMCAP(5)


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