TERMCAP(5)

NAME
termcap - terminal capability data base

SYNOPSIS
termcap

DESCRIPTION
The termcap file is a data base describing terminals, used, for example, by vi(1) and ncurses(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 understood as synonyms for the terminal name. All names but the last should be in lower case and contain no blanks; the last name may well contain upper case characters and blanks for readability.

Terminal names (except for the last, verbose entry) should be chosen using the following conventions. The particular piece of hardware making up the terminal should have a root name chosen, thus “hp2621” This name should not contain hyphens. Modes that the hardware can be in or user preferences should be indicated by appending a hyphen and an indicator of the mode. Therefore, a “vt100” in 132-column mode would be “vt100-w”. The following suffixes should be used where possible:
Suffix Meaning Example -w Wide mode (more than 80 columns) vt100-w -am With automatic margins (usually default) vt100-am -nam Without automatic margins vt100-nam -n | Number of lines on screen aaa-60 -na No arrow keys (leave them in local) concept100-na -np | Number of pages of memory concept100-4p -rv Reverse video concept100-rv

CAPABILITIES
The description field attempts to convey the semantics of the capability. You may find some codes in the description field:

(P) indicates that padding may be specified.

#[1-9]
    in the description field indicates that the string is passed through tparm(3) or tgoto(3) with parms as given (#i).

(P*)
    indicates that padding may vary in proportion to the number of lines affected.

(#i)
    indicates the ith parameter.

These are the boolean capabilities:

    Boolean			TCap	Description
    Variables		Code
    auto_left_margin	bw	cursor_left wraps from column 0	to last
    				column
    auto_right_margin	am	terminal has automatic margins
    no_esc_ctlc		xb	beehive	(f1=escape, f2=ctrl C)
    ceol_standout_glitch	xs	standout not erased by overwriting (hp)
    eat_newline_glitch	xn	newline	ignored	after 80 cols (concept)
    erase_overstrike	eo	can erase overstrikes with a blank
    generic_type		gn	generic	line type
    hard_copy		hc	hardcopy terminal
    has_meta_key		km	Has a meta key,	sets msb high
    has_status_line		hs	has extra status line
    insert_null_glitch	in	insert mode distinguishes nulls
    memory_above		da	display	may be retained	above the screen
    memory_below		db	display	may be retained	below the screen
    move_insert_mode	mi	safe to	move while in insert mode
    move_standout_mode	ms	safe to	move while in standout mode
    over_strike		os	terminal can overstrike
    status_line_esc_ok	es	escape can be used on the status line
    dest_tabs_magic_smso	xt	tabs destructive, magic	so char	(t1061)
    tilde_glitch		hz	cannot print ~'s (hazeltine)
    transparent_underline	ul	underline character overstrikes
    xon_xoff		xo	terminal uses xon/xoff handshaking
    needs_xon_xoff		nx	padding	will not work, xon/xoff required
    prtr_silent		5i	printer	will not echo on screen
    hard_cursor		HC	cursor is hard to see
    non_rev_rmcup		NR	enter_ca_mode does not reverse exit_ca_mode
    no_pad_char		NP	pad character does not exist
    non_dest_scroll_region	ND	scrolling region is non-destructive
    can_change		cc	terminal can re-define existing	colors
    back_color_erase	ut	screen erased with background color
    hue_lightness_saturation	hl	terminal uses only HLS color
    					notation (tektronix)
    col_addr_glitch		YA	only positive motion for column	address	and
    				micro_column_address caps
    cr_cancels_micro_mode	YB	using cr turns off micro mode
    has_print_wheel		YC	printer	needs operator to change character
    				set
    row_addr_glitch		YD	only positive motion for row_address and
    				micro_row_address caps
    semi_auto_right_margin	YE	printing in last column	causes cr
    cpi_changes_res		YF	changing character pitch changes resolution
    lpi_changes_res		YG	changing line pitch changes resolution

These are the numeric capabilities:

    Numeric			TCap	Description
    Variables		Code
    columns			co	number of columns in aline
    init_tabs		it	tabs initially every # spaces
    lines			li	number of lines	on screen or page
    lines_of_memory		lm	lines of memory	if > line. 0 =>	varies
    magic_cookie_glitch	sg	number of blank	chars left by
    				enter_standout_mode or exit_standout_mode
    padding_baud_rate	pb	lowest baud rate where padding needed
    virtual_terminal	vt	virtual	terminal number	(CB/unix)
    width_status_line	ws	columns	in status line
    num_labels		Nl	number of labels on screen
    label_height		lh	rows in	each label
    label_width		lw	columns	in each	label
    max_attributes		ma	maximum	combined attributes terminal can
    				handle
    maximum_windows		MW	maximum	number of definable windows
    magic_cookie_glitch_ul	ug	number of blanks left by underline
    #
    # These came in with SVr4's color support
    #
    max_colors		Co	maximum	numbers	of colors on screen
    max_pairs		pa	maximum	number of color-pairs on the screen
    no_color_video		NC	video attributes that cannot be used with
    				colors
    #
    # The following	numeric	capabilities are present in the	SVr4.0 term
    # structure, but are not yet documented	in the man page.
    # They came in with SVr4's printer support.
    #
    buffer_capacity		Ya	numbers	of bytes buffered before printing
    dot_vert_spacing	Yb	spacing	of pins	vertically in pins per inch
    dot_horz_spacing	Yc	spacing	of dots	horizontally in	dots per
    				inch
    max_micro_address	Yd	maximum	value in micro_..._address
    max_micro_jump		Ye	maximum	value in parm_..._micro
    micro_char_size		Yf	character size when in micro mode
    micro_line_size		Yg	line size when in micro	mode
    number_of_pins		Yh	numbers	of pins	in print-head
    output_res_char		Yi	horizontal resolution in units per line
    output_res_line		Yj	vertical resolution in units per line
    output_res_horz_inch	Yk	horizontal resolution in units per inch
    output_res_vert_inch	Yl	vertical resolution in units per inch
    print_rate		Ym	print rate in chars per	second
    wide_char_size		Yn	character step size when in double wide
    				mode
    buttons			BT	number of buttons on mouse
    bit_image_entwining	Yo	number of passed for each bit-image row
    bit_image_type		Yp	type of	bit-image device

These are the string capabilities:

    String			TCap	Description
    Variables		Code
    back_tab		bt	back tab (P)
    bell			bl	audible	signal (bell) (P)
    carriage_return		cr	carriage return	(P*)
    change_scroll_region	cs	change region to line #1 to line #2 (P)
    clear_all_tabs		ct	clear all tab stops (P)
    clear_screen		cl	clear screen and home cursor (P*)
    clr_eol			ce	clear to end of	line (P)
    clr_eos			cd	clear to end of	screen (P*)
    column_address		ch	horizontal position #1,	absolute (P)
    command_character	CC	terminal settable cmd character	in
    				prototype
    cursor_address		cm	move to	row #1 columns #2
    cursor_down		do	down one line
    cursor_home		ho	home cursor
    cursor_invisible	vi	make cursor invisible
    cursor_left		le	move left one space
    cursor_mem_address	CM	memory relative	cursor addressing
    cursor_normal		ve	make cursor appear normal (undo
    				cursor_invisible/cursor_visible)
    cursor_right		nd	move right one space
    cursor_to_ll		ll	last line, first column
    cursor_up		up	up one line
    cursor_visible		vs	make cursor very visible
    delete_character	dc	delete character (P*)
    delete_line		dl	delete line (P*)
    dis_status_line		ds	disable	status line
    down_half_line		hd	half a line down
    enter_alt_charset_mode	as	start alternate	character set (P)
    enter_blink_mode	mb	turn on	blinking
    enter_bold_mode		md	turn on	bold (extra bright) mode
    enter_ca_mode		ti	string to start	programs using
    				cursor_address
    enter_delete_mode	dm	enter delete mode
    enter_dim_mode		mh	turn on	half-bright mode
    enter_insert_mode	im	enter insert mode
    enter_secure_mode	mk	turn on	blank mode (characters invisible)
    enter_protected_mode	mp	turn on	protected mode
    enter_reverse_mode	mr	turn on	reverse	video mode
    enter_standout_mode	so	begin standout mode
    enter_underline_mode	us	begin underline	mode
    erase_chars		ec	erase #1 characters (P)
    exit_alt_charset_mode	ae	end alternate character	set (P)
    exit_attribute_mode	me	turn off all attributes
    exit_ca_mode		te	strings	to end programs	using cup
    exit_delete_mode	ed	end delete mode
    exit_insert_mode	ei	exit insert mode
    exit_standout_mode	se	exit standout mode
    exit_underline_mode	ue	exit underline mode
    flash_screen		vb	visible	bell (may not move cursor)
    form_feed		ff	hardcopy terminal page eject (P*)
    from_status_line	fs	return from status line
    init_1string		i1	initialization string
    init_2string		is	initialization string
    init_3string		i3	initialization string
    init_file		if	name of	initialization file
    insert_character	ic	insert character (P)
    insert_line		al	insert line (P*)
    insert_padding		ip	insert padding after inserted character
    key_backspace		kb	backspace key
    key_catab		ka	clear-all-tabs key
    key_clear		kC	clear-screen or	erase key
    key_ctab		kt	clear-tab key
    key_dc			kD	delete-character key
    key_dl			kL	delete-line key
    key_down		kd	down-arrow key
    key_eic			kM	sent by	rmir or	smir in	insert mode
    key_eol			kE	clear-to-end-of-line key
    key_eos			kS	clear-to-end-of-screen key
    key_f0			k0	F0 function key
    key_f1			k1	F1 function key
    key_f10			k;	F10 function key
    key_f2			k2	F2 function key
    key_f3			k3	F3 function key
    key_f4			k4	F4 function key
    key_f5			k5	F5 function key
    key_f6			k6	F6 function key
    key_f7			k7	F7 function key
    key_f8			k8	F8 function key
    key_f9			k9	F9 function key
    key_home		kh	home key
    key_ic			kI	insert-character key
    key_il			kA	insert-line key
    key_left		kl	left-arrow key
    key_ll			kH	last-line key
    key_npage		kN	next-page key
    key_ppage		kP	prev-page key
    key_right		kr	right-arrow key
    key_sf			kF	scroll-forward key
    key_sr			kR	scroll-backward	key
    key_stab		kT	set-tab	key
    key_up			ku	up-arrow key
    keypad_local		ke	leave 'keyboard_transmit' mode
    keypad_xmit		ks	enter 'keyboard_transmit' mode
    lab_f0			l0	label on function key f0 if not	f0
    lab_f1			l1	label on function key f1 if not	f1
    lab_f10			la	label on function key f10 if not f10
    lab_f2			l2	label on function key f2 if not	f2
    lab_f3			l3	label on function key f3 if not	f3
    lab_f4			l4	label on function key f4 if not	f4
    lab_f5			l5	label on function key f5 if not	f5
    lab_f6			l6	label on function key f6 if not	f6
    lab_f7			l7	label on function key f7 if not	f7
    lab_f8			l8	label on function key f8 if not	f8
    lab_f9			l9	label on function key f9 if not	f9
    meta_off		mo	turn off meta mode
    meta_on			mm	turn on	meta mode (8th-bit on)
    newline			nw	newline	(behave	like cr	followed by lf)
    pad_char		pc	padding	char (instead of null)
    parm_dch		DC	delete #1 chars	(P*)
    parm_delete_line	DL	delete #1 lines	(P*)
    parm_down_cursor	DO	down #1	lines (P*)
    parm_ich		IC	insert #1 chars	(P*)
    parm_index		SF	scroll forward #1 lines	(P)
    parm_insert_line	AL	insert #1 lines	(P*)
    parm_left_cursor	LE	move #1	chars to the left (P)
    parm_right_cursor	RI	move #1	chars to the right (P*)
    parm_rindex		SR	scroll back #1 lines (P)
    parm_up_cursor		UP	up #1 lines (P*)
    pkey_key		pk	program	function key #1	to type	string #2
    pkey_local		pl	program	function key #1	to execute
    				string #2
    pkey_xmit		px	program	function key #1	to transmit
    				string #2
    print_screen		ps	print contents of screen
    prtr_off		pf	turn off printer
    prtr_on			po	turn on	printer
    repeat_char		rp	repeat char #1 #2 times	(P*)
    reset_1string		r1	reset string
    reset_2string		r2	reset string
    reset_3string		r3	reset string
    reset_file		rf	name of	reset file
    restore_cursor		rc	restore	cursor to last position	of
    				save_cursor
    row_address		cv	vertical position #1 absolute (P)
    save_cursor		sc	save current cursor position (P)
    scroll_forward		sf	scroll text up (P)
    scroll_reverse		sr	scroll text down (P)
    set_attributes		sa	define video attributes	#1-#9 (PG9)
    set_tab			st	set a tab in every row,	current	columns
    set_window		wi	current	window is lines	#1-#2 cols #3-#4
    tab			ta	tab to next 8-space hardware tab stop
    to_status_line		ts	move to	status line
    underline_char		uc	underline char and move	past it
    up_half_line		hu	half a line up
    init_prog		iP	path name of program for initialization
    key_a1			K1	upper left of keypad
    key_a3			K3	upper right of keypad
    key_b2			K2	center of keypad
    key_c1			K4	lower left of keypad
    key_c3			K5	lower right of keypad
    prtr_non		pO	turn on	printer	for #1 bytes
    termcap_init2		i2	secondary initialization string
    termcap_reset		rs	terminal reset string
    #
    # SVr1 capabilities stop here.	IBM's version of terminfo is the same as
    # SVr4 up to this point, but has a different set afterwards.
    #
    char_padding		rP	like insert_padding but	when in	insert mode
    acs_chars		ac	graphics charset pairs - def=vt100
    plab_norm		pn	program	label #1 to show string	#2
    key_btab		kB	back-tab key
    enter_xon_mode		SX	turn on	xon/xoff handshaking
    exit_xon_mode		RX	turn off xon/xoff handshaking
    enter_am_mode		SA	turn on	automatic margins
    exit_am_mode		RA	turn off automatic margins
    xon_character		XN	XON character
    xoff_character		XF	XOFF character
    ena_acs			eA	enable alternate char set
    label_on		LO	turn on	soft labels
    label_off		LF	turn off soft labels
    key_beg			@1	begin key
    key_cancel		@2	cancel key
    key_close		@3	close key
    key_command		@4	command	key
    key_copy		@5	copy key
    key_create		@6	create key
    key_end			@7	end key
    key_enter		@8	enter/send key
    key_exit		@9	exit key
    key_find		@0	find key
    key_help		%1	help key
    key_mark		%2	mark key
    key_message		%3	message	key
    key_move		%4	move key
    key_next		%5	next key
    key_open		%6	open key
    key_options		%7	options	key
    key_previous		%8	previous key
    key_print		%9	print key
    key_redo		%0	redo key
    key_reference		&1	reference key
    key_refresh		&2	refresh	key
    key_replace		&3	replace	key
    key_restart		&4	restart	key
    key_resume		&5	resume key
    key_save		&6	save key
    key_suspend		&7	suspend	key
    key_undo		&8	undo key
    key_sbeg		&9	shifted	key
    key_scancel		&0	shifted	key
    key_scommand		*1	shifted	key
    key_scopy		*2	shifted	key
    key_screate		*3	shifted	key
    key_sdc			*4	shifted	key
    key_sdl			*5	shifted	key
    key_select		*6	select key
    key_send		*7	shifted	key
    key_seol		*8	shifted	key
    key_sexit		*9	shifted	key
    key_sfind		*0	shifted	key
    key_shelp		#1	shifted	key
    key_shome		#2	shifted	key
    key_sic			#3	shifted	key
    key_sleft		#4	shifted	key
    key_smessage		%a	shifted	key
    key_smove		%b	shifted	key
    key_snext		%c	shifted	key
    key_soptions		%d	shifted	key
    key_sprevious		%e	shifted	key
    key_sprint		%f	shifted	key
    key_sredo		%g	shifted	key
    key_sreplace		%h	shifted	key
    key_sright		%i	shifted	key
    key_srsume		%j	shifted	key
    key_ssave		!1	shifted	key
    key_ssuspend		!2	shifted	key
    key_sundo		!3	shifted	key
    req_for_input		RF	send next input	char (for ptys)
    key_f11			F1	F11 function key
    key_f12			F2	F12 function key
    key_f13			F3	F13 function key
    key_f14			F4	F14 function key
    key_f15			F5	F15 function key
    key_f16			F6	F16 function key
    key_f17			F7	F17 function key
    key_f18			F8	F18 function key
    key_f19			F9	F19 function key
    key_f20			FA	F20 function key
    key_f21			FB	F21 function key
    key_f22			FC	F22 function key
    key_f23			FD	F23 function key
    key_f24			FE	F24 function key
    key_f25			FF	F25 function key
    key_f26			FG	F26 function key
    key_f27			FH	F27 function key
    key_f28			FI	F28 function key
    key_f29			FJ	F29 function key
    key_f30			FK	F30 function key
    key_f31			FL	F31 function key
    key_f32			FM	F32 function key
    key_f33			FN	F33 function key
    key_f34			FO	F34 function key
    key_f35			FP	F35 function key
    key_f36			FQ	F36 function key
    key_f37			FR	F37 function key
    key_f38			FS	F38 function key
    key_f39			FT	F39 function key
    key_f40			FU	F40 function key
    key_f41			FV	F41 function key
    key_f42			FW	F42 function key
    key_f43			FX	F43 function key
    key_f44			FY	F44 function key
    key_f45			FZ	F45 function key
    key_f46			Fa	F46 function key
    key_f47			Fb	F47 function key
    key_f48			Fc	F48 function key
    key_f49			Fd	F49 function key
    key_f50			Fe	F50 function key
    key_f51			Ff	F51 function key
    key_f52			Fg	F52 function key
    key_f53			Fh	F53 function key
    key_f54			Fi	F54 function key
    key_f55			Fj	F55 function key
    key_f56			Fk	F56 function key
    key_f57			Fl	F57 function key
    key_f58			Fm	F58 function key
    key_f59			Fn	F59 function key
    key_f60			Fo	F60 function key
    key_f61			Fp	F61 function key
    key_f62			Fq	F62 function key
    key_f63			Fr	F63 function key
    clr_bol			cb	Clear to beginning of line
    clear_margins		MC	clear right and	left soft margins
    set_left_margin		ML	set left soft margin
    set_right_margin	MR	set right soft margin
    label_format		Lf	label format
    set_clock		SC	set clock, #1 hrs #2 mins #3 secs
    display_clock		DK	display	clock at (#1,#2)
    remove_clock		RC	remove clock
    create_window		CW	define a window	#1 from	#2, #3 to #4, #5
    goto_window		WG	go to window #1
    hangup			HU	hang-up	phone
    dial_phone		DI	dial number #1
    quick_dial		QD	dial number #1 without checking
    tone			TO	select touch tone dialing
    pulse			PU	select pulse dialling
    flash_hook		fh	flash switch hook
    fixed_pause		PA	pause for 2-3 seconds
    wait_tone		WA	wait for dial-tone
    user0			u0	User string #0
    user1			u1	User string #1
    user2			u2	User string #2
    user3			u3	User string #3
    user4			u4	User string #4
    user5			u5	User string #5
    user6			u6	User string #6
    user7			u7	User string #7
    user8			u8	User string #8
    user9			u9	User string #9
    #
    # SVr4 added these capabilities to support color
    #
    orig_pair		op	Set default pair to its	original value
    orig_colors		oc	Set all	color pairs to the original ones
    initialize_color	Ic	initialize color #1 to (#2,#3,#4)
    initialize_pair		Ip	Initialize color pair #1 to fg=(#2,#3,#4),
    				bg=(#5,#6,#7)
    set_color_pair		sp	Set current color pair to #1
    set_foreground		Sf	Set foreground color #1
    set_background		Sb	Set background color #1
    #
    # SVr4 added these capabilities to support printers
    #
    change_char_pitch	ZA	Change number of characters per	inch
    change_line_pitch	ZB	Change number of lines per inch
    change_res_horz		ZC	Change horizontal resolution
    change_res_vert		ZD	Change vertical	resolution
    define_char		ZE	Define a character
    enter_doublewide_mode	ZF	Enter double-wide mode
    enter_draft_quality	ZG	Enter draft-quality mode
    enter_italics_mode	ZH	Enter italic mode
    enter_leftward_mode	ZI	Start leftward carriage	motion
    enter_micro_mode	ZJ	Start micro-motion mode
    enter_near_letter_quality	ZK	Enter NLQ mode
    enter_normal_quality	ZL	Enter normal-quality mode
    enter_shadow_mode	ZM	Enter shadow-print mode
    enter_subscript_mode	ZN	Enter subscript	mode
    enter_superscript_mode	ZO	Enter superscript mode
    enter_upward_mode	ZP	Start upward carriage motion
    exit_doublewide_mode	ZQ	End double-wide	mode
    exit_italics_mode	ZR	End italic mode
    exit_leftward_mode	ZS	End left-motion	mode
    exit_micro_mode		ZT	End micro-motion mode
    exit_shadow_mode	ZU	End shadow-print mode
    exit_subscript_mode	ZV	End subscript mode
    exit_superscript_mode	ZW	End superscript	mode
    exit_upward_mode	ZX	End reverse character motion
    micro_column_address	ZY	Like column_address in micro mode
    micro_down		ZZ	Like cursor_down in micro mode
    micro_left		Za	Like cursor_left in micro mode
    micro_right		Zb	Like cursor_right in micro mode
    micro_row_address	Zc	Like row_address in micro mode
    micro_up		Zd	Like cursor_up in micro	mode
    order_of_pins		Ze	Match software bits to print-head pins
    parm_down_micro		Zf	Like parm_down_cursor in micro mode
    parm_left_micro		Zg	Like parm_left_cursor in micro mode
    parm_right_micro	Zh	Like parm_right_cursor in micro	mode
    parm_up_micro		Zi	Like parm_up_cursor in micro mode
    select_char_set		Zj	Select character set
    set_bottom_margin	Zk	Set bottom margin at current line
    set_bottom_margin_parm	Zl	Set bottom margin at line #1 or	#2 lines
    				from bottom
    set_left_margin_parm	Zm	Set left (right) margin	at column #1 (#2)
    set_right_margin_parm	Zn	Set right margin at column #1
    set_top_margin		Zo	Set top	margin at current line
    set_top_margin_parm	Zp	Set top	(bottom) margin	at row #1 (#2)
    start_bit_image		Zq	Start printing bit image graphics
    start_char_set_def	Zr	Start character	set definition
    stop_bit_image		Zs	Stop printing bit image	graphics
    stop_char_set_def	Zt	End definition of character aet
    subscript_characters	Zu	List of	subscriptible characters
    superscript_characters	Zv	List of	superscriptible	characters
    these_cause_cr		Zw	Printing any of	these chars causes CR
    zero_motion		Zx	No motion for subsequent character
    #
    # The following	string capabilities are	present	in the SVr4.0 term
    # structure, but are not documented in the man page.
    #
    char_set_names		Zy	List of	character set names
    key_mouse		Km	Mouse event has	occurred
    mouse_info		Mi	Mouse status information
    req_mouse_pos		RQ	Request	mouse position
    get_mouse		Gm	Curses should get button events
    set_a_foreground	AF	Set ANSI foreground color
    set_a_background	AB	Set ANSI background color
    pkey_plab		xl	Program	function key #1	to type	string #2
    				and show string	#3
    device_type		dv	Indicate language/codeset support
    code_set_init		ci	Init sequence for multiple codesets
    set0_des_seq		s0	Shift to code set 0 (EUC set 0,	ASCII)
    set1_des_seq		s1	Shift to code set 1
    set2_des_seq		s2	Shift to code set 2
    set3_des_seq		s3	Shift to code set 3
    set_lr_margin		ML	Set both left and right	margins	to #1, #2
    set_tb_margin		MT	Sets both top and bottom margins to #1,	#2
    bit_image_repeat	Xy	Repeat bit image cell #1 #2 times
    bit_image_newline	Zz	Move to	next row of the	bit image
    bit_image_carriage_return	Yv	Move to	beginning of same row
    color_names		Yw	Give name for color #1
    define_bit_image_region	Yx	Define rectangular bit image region
    end_bit_image_region	Yy	End a bit-image	region
    set_color_band		Yz	Change to ribbon color #1
    set_page_length		YZ	Set page length	to #1 lines
    #
    # SVr4 added these capabilities for direct PC-clone support
    #
    display_pc_char		S1	Display	PC character
    enter_pc_charset_mode	S2	Enter PC character display mode
    exit_pc_charset_mode	S3	Exit PC	character display mode
    enter_scancode_mode	S4	Enter PC scancode mode
    exit_scancode_mode	S5	Exit PC	scancode mode
    pc_term_options		S6	PC terminal options
    scancode_escape		S7	Escape for scancode emulation
    alt_scancode_esc	S8	Alternate escape for scancode emulation
    #
    # The XSI Curses standard added	these.
    #
    enter_horizontal_hl_mode	Xh	Enter horizontal highlight mode
    enter_left_hl_mode	Xl	Enter left highlight mode
    enter_low_hl_mode	Xo	Enter low highlight mode
    enter_right_hl_mode	Xr	Enter right highlight mode
    enter_top_hl_mode	Xt	Enter top highlight mode
    enter_vertical_hl_mode	Xv	Enter vertical highlight mode

Obsolete termcap capabilities. New software should not rely on them at all.

    Boolean			TCap	Description
    Variables		Code
    linefeed_is_newline	NL	move down with ^J
    even_parity		EP	terminal requires even parity
    odd_parity		OP	terminal requires odd parity
    half_duplex		HD	terminal is half-duplex
    lower_case_only		LC	terminal has only lower	case
    upper_case_only		UC	terminal has only upper	case
    has_hardware_tabs	pt	has 8-char tabs	invoked	with ^I
    return_does_clr_eol	xr	return clears the line
    tek_4025_insert_line	xx	Tektronix 4025 insert-line glitch
    backspaces_with_bs	bs	uses ^H	to move	left
    crt_no_scrolling	ns	crt cannot scroll
    no_correctly_working_cr	nc	no way to go to	start of line

    Number			TCap	Description
    Variables		Code
    backspace_delay		dB	padding	required for ^H
    form_feed_delay		dF	padding	required for ^L
    horizontal_tab_delay	dT	padding	required for ^I
    vertical_tab_delay	dV	padding	required for ^V
    number_of_function_keys	kn	count of function keys
    carriage_return_delay	dC	pad needed for CR
    new_line_delay		dN	pad needed for LF

    String			TCap	Description
    Variables		Code
    other_non_function_keys	ko	list of	self-mapped keycaps
    arrow_key_map		ma	map arrow keys
    memory_lock_above	ml	lock visible screen memory above the
    				current	line
    memory_unlock		mu	unlock visible screen memory above the
    				current	line
    linefeed_if_not_lf	nl	use to move down
    backspace_if_not_bs	bc	move left, if not ^H

  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%+ %+ :\
    	:co#80:.cr=9^M:db:dc=16\E^A:dl=3*\E^B:do=^J:ei=\E\200:eo:im=\E^P:in:\
    	:ip=16*:is=\EU\Ef\E7\E5\E8\El\ENH\EK\E\200\Eo&\200\Eo\47\E:k1=\E5:\
    	:k2=\E6:k3=\E7:kb=^h:kd=\E<:ke=\Ex:kh=\E?:kl=\E>:kr=\E=:ks=\EX:\
    	:ku=\E;:le=^H:li#24:mb=\EC:me=\EN\200:mh=\EE:mi:mk=\EH:mp=\EI:\
    	:mr=\ED:nd=\E=:pb#9600:rp=0.2*\Er%.%+ :se=\Ed\Ee:sf=^J:so=\EE\ED:\
    	:.ta=8\t:te=\Ev    \200\200\200\200\200\200\Ep\r\n:\
    	:ti=\EU\Ev  8p\Ep\r:ue=\Eg:ul:up=\E;:us=\EG:\
    	:vb=\Ek\200\200\200\200\200\200\200\200\200\200\200\200\200\200\EK:\
    	:ve=\Ew:vs=\EW:vt#8:xn:\
    	:bs:cr=^M:dC#9:dT#8:nl=^J:ta=^I:pt:

Entries may continue onto multiple lines by giving a \ as the last character of a line, and empty fields may be included for readability (here between the last field on a line and the first field on the next). Comments may be included on lines beginning with “#”.

  Types of Capabilities
Capabilities in termcap are of three types: Boolean capabilities, which indicate particular features that the terminal has; numeric capabilities, 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.

Numeric capabilities are followed by the character `#' then the value. In the example above co, which indicates the number of columns the display has, gives the value `80' for the Concept.

Finally, string-valued capabilities, such as ce (clear-to-end-of-line sequence) are given by the two-letter code, an `=', then a string ending at the next following `:'. A delay in milliseconds may appear after the `=' in such a capability, which causes padding characters to be supplied by tputs(3) after the remainder of the string is sent to provide this delay. The delay can be either a number, such as `20', or a number followed by an `*', such as `3*'. An `*' indicates that the padding required is proportional to the number of lines affected by the operation, and the amount given is the per-affected-line padding required. (In the case of insert-character, the factor is still the number of lines affected; this is always 1 unless the terminal has in and the software uses it.) When an `*' is specified, it is sometimes useful to give a delay of the form `3.5' to specify a delay per line to tenths of milliseconds. (Only one decimal place is allowed.)

A number of escape sequences are provided in the string-valued capabilities for easy encoding of control characters there. \E maps to an ESC character, ^X maps to a control-X for any appropriate X, and the sequences \n \r \t \b \f map to linefeed, return, tab, backspace, and formfeed, respectively. Finally, characters may be given as three octal digits after a \, and the characters ^ and \ may be given as \^ and \\. If it is necessary to place a: in a capability it must be escaped as \: or be encoded 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
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(1) 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(1). 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 pathnames (separated by spaces or colons), one of which contains the description you are working on, and programs will search them in the order listed, and nowhere else. See termcap(3). The TERMCAP environment variable is usually set to the termcap entry itself to avoid reading files when starting up a program.

To get the padding for insert-line right (if the terminal manufacturer did not document it), a severe test is to use vi(1) to edit /etc/passwd at 9600 baud, delete roughly 16 lines from the middle of the screen, then hit the `u' key several times quickly. If the display messes up, more padding is usually needed. A similar test can be used for insert-character.

  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 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. (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 display. Programs should never attempt to backspace around the left edge, unless bw is given, and never attempt to go up off the top using local cursor motions.

In order to scroll text up, a program goes to the bottom left corner of the screen and sends the sf (index) string. To scroll text down, a program goes to the top left corner of the screen and sends the sr (reverse index) string. The strings sf and sr have undefined behavior when not on their respective corners of the screen. Parameterized versions of the scrolling sequences are SF and SR, which have the same semantics as sf and sr except that they take one parameter and scroll that many lines. They also have undefined behavior except at the appropriate corner of the screen.

The am capability tells whether the cursor sticks at the right edge of the screen when text is output there, but this does not necessarily apply to nd from the last column. Leftward local motion is defined from the left edge only when bw is given; then an le from the left edge will move to the right edge of the previous row. This is useful for drawing a box around the edge of the screen, for example. If the terminal has switch-selectable automatic margins, the termcap description usually assumes that this feature is on, i.e., am. If the terminal has a command that moves to the first column of the next line, that command can be given as nw (newline). It is permissible for this to clear the remainder of the current line, so if the terminal has no correctly-working CR and LF it may still be possible to craft a working nw out of one or both of them.

These capabilities suffice to describe hardcopy and “glass-tty” terminals. Thus the Teletype model 33 is described as

    T3|tty33|33|tty|Teletype model 33:\
    	:bl=^G:co#72:cr=^M:do=^J:hc:os:

and the Lear Siegler ADM-3 is described as

    l3|adm3|3|LSI ADM-3:\
    :am:bl=^G:cl=^Z:co#80:cr=^M:do=^J:le=^H:li#24:sf=^J:

  Parameterized Strings
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(3) %d
%2 | output value as in
printf(3) %2d
%3 | output value as in
printf(3) %3d
%. | output value as in
printf(3) %c
%+x | add
x to value, then do %.
%>xy | if
value > x then add y, no output
%r | reverse order of two parameters, no output
%i | increment by one, no output
%n | exclusive-or all parameters with 0140 (Datamedia 2500)
%B | BCD (16*(value/10)) + (value%10), no output
%D | Reverse coding (value - 2*(value%16)), no output (Delta Data).

Consider the Hewlett-Packard 2645, which, to get to row 3 and column 12, needs to be sent “\E&a12c03Y” padded for 6 milliseconds. Note that the order of the row and column coordinates is reversed here and that the row and column are sent as two-digit integers. Thus its cm capability is “cm=6\E&%r%2c%2Y”.

The Datamedia 2500 needs the current row and column sent encoded in binary using “%.”. Terminals that use “%.” need to be able to backspace the cursor (le) 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 column by a blank character, thus “cm=\E=%+ %+ ”.

Row or column absolute cursor addressing can be given as single parameter capabilities ch (horizontal position absolute) and cv (vertical position absolute). Sometimes these are shorter than the more general two-parameter sequence (as with the Hewlett-Packard 2645) and can be used in preference to cm. If there are parameterized local motions (e.g., move n positions to the right) these can be given as DO, LE, RI, and UP with a single parameter indicating how many positions to move. These are primarily useful if the terminal does not have cm, such as the Tektronix 4025.

  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” sequence 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 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 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) 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(5) 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.

The termcap entries can describe both terminals that have an insert mode and terminals that send a simple sequence to open a blank position on the current line. Give as im the sequence to get into insert mode. Give as ei the sequence to leave insert mode. Now give as ic any sequence that needs to be sent just before each character to be inserted. Most terminals with a true insert mode will not give ic; terminals that use a sequence to open a screen position should give it here. (If your terminal has both, insert mode is usually preferable to ic. Do not give both unless the terminal actually requires both to be used in combination.) If post-insert padding is needed, give this as a number of milliseconds in ip (a string option). Any other sequence that may need to be sent after insertion of a single character can also be given in ip. If your terminal needs to be placed into an `insert mode' and needs a special code preceding each inserted character, then both im/ ei and ic can be given, and both will be used. The IC capability, with one parameter n, will repeat the effects of ic n times.

It is occasionally necessary to move around while in insert mode to delete characters on the same line (e.g., if there is a tab after the insertion position). If your terminal allows motion while in insert mode, you can give the capability mi to speed up inserting in this case. Omitting mi will affect only speed. Some terminals (notably Datamedia's) must not have mi because of the way their insert mode works.

Finally, you can specify dc to delete a single character, DC with one parameter n to delete n characters, and delete mode by giving dm and ed to enter and exit delete mode (which is any mode the terminal needs to be placed in for dc to work).

  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 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 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 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(5).)

Terminals with the “magic cookie” glitches (sg and ug), rather than maintaining extra attribute bits for each character cell, instead deposit special “cookies”, or “garbage characters”, when they receive mode-setting sequences, which affect the display algorithm.

Some terminals, such as the Hewlett-Packard 2621, automatically leave standout mode when they move to a new line or when the cursor is addressed. Programs using standout mode should exit standout mode on such terminals before moving the cursor or sending a newline. On terminals where this is not a problem, the ms capability should be present to say that this overhead is unnecessary.

If the terminal has a way of flashing the screen to indicate an error quietly (a bell replacement), this can be given as vb; it must not move the cursor.

If the cursor needs to be made more visible than normal when it is not on the bottom line (to change, for example, a non-blinking underline into an easier-to-find block or blinking underline), give this sequence as vs. If there is a way to make the cursor completely invisible, give that as vi. The capability ve, which undoes the effects of both of these modes, should also be given.

If your terminal correctly displays underlined characters (with no special codes needed) even though it does not overstrike, then you should give the capability ul. If overstrikes are erasable with a blank, this should be indicated by giving eo.

  Keypad
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 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 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 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 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
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(1) program each time the user logs in. They will be printed in the following order: is; setting tabs using ct and st; and finally if. (Terminfo uses i1-i2 instead of is and runs the program iP and prints i3 after the other initializations.) A pair of sequences that does a harder reset from a totally unknown state can be analogously given as rs and if. These strings are output by the reset(1) program, which is used when the terminal gets into a wedged state. (Terminfo uses r1-r3 instead of rs.) Commands are normally placed in rs and rf only if they produce annoying effects on the screen and are not necessary when logging in. For example, the command to set the VT100 into 80-column mode would normally be part of is, but it causes an annoying glitch of the screen and is not normally needed since the terminal is usually already in 80-column mode.

If the terminal has hardware tabs, the command to advance to the next tab stop can be given as ta (usually ^I). A “backtab” command which moves leftward to the previous tab stop can be given as bt. By convention, if the terminal driver modes indicate that tab stops are being expanded by the computer rather than being sent to the terminal, programs should not use ta or bt even if they are present, since the user may not have the tab stops properly set. If the terminal has hardware tabs that are initially set every n positions when the terminal is powered up, then the numeric parameter it is given, showing the number of positions between tab stops. This is normally used by the tset(1) command to determine whether to set the driver mode for hardware tab expansion, and whether to set the tab stops. If the terminal has tab stops that can be saved in nonvolatile memory, the termcap description can assume that they are properly set.

If there are commands to set and clear tab stops, they can be given as ct (clear all tab stops) and st (set a tab stop in the current column of every row). If a more complex sequence is needed to set the tabs than can be described by this, the sequence can be placed in is or if.

  Delays
Certain capabilities control padding in the terminal driver. These are primarily needed by hardcopy terminals and are used by the tset(1) 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(1), the delays are given as numeric capabilities dC, dN, dB, dF, and dT instead.

  Miscellaneous
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 otherwise erases its contents) should be given as ds. The status line is normally assumed to be the same width as the rest of the screen, i.e., co. If the status line is a different width (possibly because the terminal does not allow an entire line to be loaded), then its width in columns can be indicated with the numeric parameter ws.

If the terminal can move up or down half a line, this can be indicated with hu (half-line up) and hd (half-line down). This is primarily useful for superscripts and subscripts on hardcopy terminals. If a hardcopy terminal can eject to the next page (form feed), give this as ff (usually ^L).

If there is a command to repeat a given character a given number of times (to save time transmitting a large number of identical characters), this can be indicated with the parameterized string rp. The first parameter is the character to be repeated and the second is the number of times to repeat it. (This is a terminfo(5) feature that is unlikely to be supported by a program that uses 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 make(1).

Terminal descriptions that do not represent a specific kind of known terminal, such as switch, dialup, patch, and network, should include the gn (generic) capability so that programs can complain that they do not know how to talk to the terminal. (This capability does not apply to virtual terminal descriptions for which the escape sequences are known.)

If the terminal uses xoff/xon (DC3/DC1) handshaking for flow control, give xo. Padding information should still be included so that routines can make better decisions about costs, but actual pad characters will not be transmitted.

If the terminal has a “meta key” which acts as a shift key, setting the 8th bit of any character transmitted, then this fact can be indicated with km. Otherwise, software will assume that the 8th bit is parity and it will usually be cleared. If strings exist to turn this “meta mode” on and off, they can be given as mm and mo.

If the terminal has more lines of memory than will fit on the screen at once, the number of lines of memory can be indicated with lm. An explicit value of 0 indicates that the number of lines is not fixed, but that there is still more memory than fits on the screen.

If the terminal is one of those supported by the UNIX system virtual terminal protocol, the terminal number can be given as vt.

Media copy strings which control an auxiliary printer connected to the terminal can be given as ps: print the contents of the screen; pf: turn off the printer; and po: turn on the printer. When the printer is on, all text sent to the terminal will be sent to the printer. It is undefined whether the text is also displayed on the terminal screen when the printer is on. A variation pO takes one parameter and leaves the printer on for as many characters as the value of the parameter, then turns the printer off. The parameter should not exceed 255. All text, including pf, is transparently passed to the printer while pO is in effect.

Strings to program function keys can be given as pk, pl, and px. Each of these strings takes two parameters: the function key number to program (from 0 to 9) and the string to program it with. Function key numbers out of this range may program undefined keys in a terminal-dependent manner. The differences among the capabilities are that pk causes pressing the given key to be the same as the user typing the given string; pl causes the string to be executed by the terminal in local mode; and px causes the string to be transmitted to the computer. Unfortunately, due to lack of a definition for string parameters in termcap, only terminfo(5) supports these capabilities.

For the xterm(1) terminal emulator the traditional behavior in FreeBSD when exiting a pager such as less(1) or more(1), or an editor such as vi(1) is NOT to clear the screen after the program exits. If you prefer to clear the screen there are a number of “xterm-clear” entries that add this capability in the termcap file that you can use directly, or as examples.

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

The nc capability, now obsolete, formerly indicated Datamedia terminals, which echo \r \n for carriage return then ignore a following linefeed.

Terminals that ignore a linefeed immediately after an am wrap, such as the Concept, should indicate xn.

If ce is required to get rid of standout (instead of merely writing normal text on top of it), xs should be given.

Teleray terminals, where tabs turn all characters moved over to blanks, should indicate xt (destructive tabs). This glitch is also taken to mean that it is not possible to position the cursor on top of a “magic cookie”, and that to erase standout mode it is necessary to use delete and insert line.

The Beehive Superbee, which is unable to correctly transmit the ESC or ^C characters, has xb, indicating that the “f1” key is used for ESC and “f2” for ^C. (Only certain Superbees have this problem, depending on the ROM.)

Other specific terminal problems may be corrected by adding more capabilities of the form x x.

  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

    hn|2621-nl:ks@:ke@:tc=2621:

defines a “2621-nl” that does not have the ks or ke capabilities, hence does not turn on the function key labels when in visual mode. This is useful for different modes for a terminal, or for different user preferences.

FILES
/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
cap_mkdb(1), ex(1), more(1), tset(1), ul(1), vi(1), xterm(1), ncurses(3), printf(3), termcap(3), term(5)

CAVEATS AND BUGS
The Note: termcap functions were replaced by terminfo(5) in AT&T 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.

The vi(1) program 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 exceed 1024.

Not all programs support all entries.

HISTORY
The termcap file format appeared in 3BSD.