path: root/runtime/doc/term.txt

*term.txt*      For Vim version 8.2.  Last change: 2021 Jan 14


		  VIM REFERENCE MANUAL    by Bram Moolenaar


Terminal information					*terminal-info*

Vim uses information about the terminal you are using to fill the screen and
recognize what keys you hit.  If this information is not correct, the screen
may be messed up or keys may not be recognized.  The actions which have to be
performed on the screen are accomplished by outputting a string of
characters.  Special keys produce a string of characters.  These strings are
stored in the terminal options, see |terminal-options|.

NOTE: Most of this is not used when running the |GUI|.

1. Startup			|startup-terminal|
2. Terminal options		|terminal-options|
3. Window size			|window-size|
4. Slow and fast terminals	|slow-fast-terminal|
5. Using the mouse		|mouse-using|

==============================================================================
1. Startup						*startup-terminal*

When Vim is started a default terminal type is assumed.  For the Amiga this is
a standard CLI window, for MS-Windows the pc terminal, for Unix an ansi
terminal.  A few other terminal types are always available, see below
|builtin-terms|.

You can give the terminal name with the '-T' Vim argument.  If it is not given
Vim will try to get the name from the TERM environment variable.

				*termcap* *terminfo* *E557* *E558* *E559*
On Unix the terminfo database or termcap file is used.  This is referred to as
"termcap" in all the documentation.  At compile time, when running configure,
the choice whether to use terminfo or termcap is done automatically.  When
running Vim the output of ":version" will show |+terminfo| if terminfo is
used.  Also see |xterm-screens|.

On non-Unix systems a termcap is only available if Vim was compiled with
TERMCAP defined.

					*builtin-terms* *builtin_terms*
Which builtin terminals are available depends on a few defines in feature.h,
which need to be set at compile time:
    define		output of ":version"	terminals builtin	~
NO_BUILTIN_TCAPS	-builtin_terms		none
SOME_BUILTIN_TCAPS	+builtin_terms		most common ones (default)
ALL_BUILTIN_TCAPS	++builtin_terms		all available

You can see a list of available builtin terminals with ":set term=xxx" (when
not running the GUI).  Also see |+builtin_terms|.

If the termcap code is included Vim will try to get the strings for the
terminal you are using from the termcap file and the builtin termcaps.  Both
are always used, if an entry for the terminal you are using is present.  Which
one is used first depends on the 'ttybuiltin' option:

'ttybuiltin' on		1: builtin termcap	2: external termcap
'ttybuiltin' off	1: external termcap	2: builtin termcap

If an option is missing in one of them, it will be obtained from the other
one.  If an option is present in both, the one first encountered is used.

Which external termcap file is used varies from system to system and may
depend on the environment variables "TERMCAP" and "TERMPATH".  See "man
tgetent".

Settings depending on terminal			*term-dependent-settings*

If you want to set options or mappings, depending on the terminal name, you
can do this best in your .vimrc.  Example: >

   if &term == "xterm"
     ... xterm maps and settings ...
   elseif &term =~ "vt10."
     ... vt100, vt102 maps and settings ...
   endif
<
						*raw-terminal-mode*
For normal editing the terminal will be put into "raw" mode.  The strings
defined with 't_ti', 't_TI' and 't_ks' will be sent to the terminal.  Normally
this puts the terminal in a state where the termcap codes are valid and
activates the cursor and function keys.
When Vim exits the terminal will be put back into the mode it was before Vim
started.  The strings defined with 't_te', 't_TE' and 't_ke' will be sent to
the terminal.  On the Amiga, with commands that execute an external command
(e.g., "!!"), the terminal will be put into Normal mode for a moment.  This
means that you can stop the output to the screen by hitting a printing key.
Output resumes when you hit <BS>.

Note: When 't_ti' is not empty, Vim assumes that it causes switching to the
alternate screen.  This may slightly change what happens when executing a
shell command or exiting Vim.  To avoid this use 't_TI' and 't_TE'.

						*xterm-bracketed-paste*
When the 't_BE' option is set then 't_BE' will be sent to the
terminal when entering "raw" mode and 't_BD' when leaving "raw" mode.  The
terminal is then expected to put 't_PS' before pasted text and 't_PE' after
pasted text.  This way Vim can separate text that is pasted from characters
that are typed.  The pasted text is handled like when the middle mouse button
is used, it is inserted literally and not interpreted as commands.

When the cursor is in the first column, the pasted text will be inserted
before it.  Otherwise the pasted text is appended after the cursor position.
This means one cannot paste after the first column.  Unfortunately Vim does
not have a way to tell where the mouse pointer was.

Note that in some situations Vim will not recognize the bracketed paste and
you will get the raw text.  In other situations Vim will only get the first
pasted character and drop the rest, e.g. when using the "r" command.  If you
have a problem with this, disable bracketed paste by putting this in your
.vimrc: >
	set t_BE=
If this is done while Vim is running the 't_BD' will be sent to the terminal
to disable bracketed paste.

If your terminal supports bracketed paste, but the options are not set
automatically, you can try using something like this: >

	if &term =~ "screen"
	  let &t_BE = "\e[?2004h"
	  let &t_BD = "\e[?2004l"
	  exec "set t_PS=\e[200~"
	  exec "set t_PE=\e[201~"
	endif
<
							*cs7-problem*
Note: If the terminal settings are changed after running Vim, you might have
an illegal combination of settings.  This has been reported on Solaris 2.5
with "stty cs8 parenb", which is restored as "stty cs7 parenb".  Use
"stty cs8 -parenb -istrip" instead, this is restored correctly.

Some termcap entries are wrong in the sense that after sending 't_ks' the
cursor keys send codes different from the codes defined in the termcap.  To
avoid this you can set 't_ks' (and 't_ke') to empty strings.  This must be
done during initialization (see |initialization|), otherwise it's too late.

Some termcap entries assume that the highest bit is always reset.  For
example: The cursor-up entry for the Amiga could be ":ku=\E[A:".  But the
Amiga really sends "\233A".  This works fine if the highest bit is reset,
e.g., when using an Amiga over a serial line.  If the cursor keys don't work,
try the entry ":ku=\233A:".

Some termcap entries have the entry ":ku=\E[A:".  But the Amiga really sends
"\233A".  On output "\E[" and "\233" are often equivalent, on input they
aren't.  You will have to change the termcap entry, or change the key code with
the :set command to fix this.

Many cursor key codes start with an <Esc>.  Vim must find out if this is a
single hit of the <Esc> key or the start of a cursor key sequence.  It waits
for a next character to arrive.  If it does not arrive within one second a
single <Esc> is assumed.  On very slow systems this may fail, causing cursor
keys not to work sometimes.  If you discover this problem reset the 'timeout'
option.  Vim will wait for the next character to arrive after an <Esc>.  If
you want to enter a single <Esc> you must type it twice.  Resetting the
'esckeys' option avoids this problem in Insert mode, but you lose the
possibility to use cursor and function keys in Insert mode.

On the Amiga the recognition of window resizing is activated only when the
terminal name is "amiga" or "builtin_amiga".

Some terminals have confusing codes for the cursor keys.  The televideo 925 is
such a terminal.  It sends a CTRL-H for cursor-left.  This would make it
impossible to distinguish a backspace and cursor-left.  To avoid this problem
CTRL-H is never recognized as cursor-left.

					*vt100-cursor-keys* *xterm-cursor-keys*
Other terminals (e.g., vt100 and xterm) have cursor keys that send <Esc>OA,
<Esc>OB, etc.  Unfortunately these are valid commands in insert mode: Stop
insert, Open a new line above the new one, start inserting 'A', 'B', etc.
Instead of performing these commands Vim will erroneously recognize this typed
key sequence as a cursor key movement.  To avoid this and make Vim do what you
want in either case you could use these settings: >
	:set notimeout		" don't timeout on mappings
	:set ttimeout		" do timeout on terminal key codes
	:set timeoutlen=100	" timeout after 100 msec
This requires the key-codes to be sent within 100 msec in order to recognize
them as a cursor key.  When you type you normally are not that fast, so they
are recognized as individual typed commands, even though Vim receives the same
sequence of bytes.

				*vt100-function-keys* *xterm-function-keys*
An xterm can send function keys F1 to F4 in two modes: vt100 compatible or
not.  Because Vim may not know what the xterm is sending, both types of keys
are recognized.  The same happens for the <Home> and <End> keys.
			normal			vt100 ~
	<F1>	t_k1	<Esc>[11~	<xF1>	<Esc>OP	    *<xF1>-xterm*
	<F2>	t_k2	<Esc>[12~	<xF2>	<Esc>OQ	    *<xF2>-xterm*
	<F3>	t_k3	<Esc>[13~	<xF3>	<Esc>OR	    *<xF3>-xterm*
	<F4>	t_k4	<Esc>[14~	<xF4>	<Esc>OS	    *<xF4>-xterm*
	<Home>	t_kh	<Esc>[7~	<xHome>	<Esc>OH	    *<xHome>-xterm*
	<End>	t_@7	<Esc>[4~	<xEnd>	<Esc>OF	    *<xEnd>-xterm*

When Vim starts, <xF1> is mapped to <F1>, <xF2> to <F2> etc.  This means that
by default both codes do the same thing.  If you make a mapping for <xF2>,
because your terminal does have two keys, the default mapping is overwritten,
thus you can use the <F2> and <xF2> keys for something different.

							*xterm-shifted-keys*
Newer versions of xterm support shifted function keys and special keys.  Vim
recognizes most of them.  Use ":set termcap" to check which are supported and
what the codes are.  Mostly these are not in a termcap, they are only
supported by the builtin_xterm termcap.

							*xterm-modifier-keys*
Newer versions of xterm support Alt and Ctrl for most function keys.  To avoid
having to add all combinations of Alt, Ctrl and Shift for every key a special
sequence is recognized at the end of a termcap entry: ";*X".  The "X" can be
any character, often '~' is used.  The ";*" stands for an optional modifier
argument.  ";2" is Shift, ";3" is Alt, ";5" is Ctrl and ";9" is Meta (when
it's different from Alt).  They can be combined.  Examples: >
	:set <F8>=^[[19;*~
	:set <Home>=^[[1;*H
Another speciality about these codes is that they are not overwritten by
another code.  That is to avoid that the codes obtained from xterm directly
|t_RV| overwrite them.

Another special value is a termcap entry ending in "@;*X".  This is for cursor
keys, which either use "CSI X" or "CSI 1 ; modifier X".  Thus the "@"
stands for either "1" if a modifier follows, or nothing.
							*xterm-scroll-region*
The default termcap entry for xterm on Sun and other platforms does not
contain the entry for scroll regions.  Add ":cs=\E[%i%d;%dr:" to the xterm
entry in /etc/termcap and everything should work.

							*xterm-end-home-keys*
On some systems (at least on FreeBSD with XFree86 3.1.2) the codes that the
<End> and <Home> keys send contain a <Nul> character.  To make these keys send
the proper key code, add these lines to your ~/.Xdefaults file:

*VT100.Translations:		#override \n\
		<Key>Home: string("0x1b") string("[7~") \n\
		<Key>End: string("0x1b") string("[8~")

						*xterm-8bit* *xterm-8-bit*
Xterm can be run in a mode where it uses 8-bit escape sequences.  The CSI code
is used instead of <Esc>[.  The advantage is that an <Esc> can quickly be
recognized in Insert mode, because it can't be confused with the start of a
special key.
For the builtin termcap entries, Vim checks if the 'term' option contains
"8bit" anywhere.  It then uses 8-bit characters for the termcap entries, the
mouse and a few other things.  You would normally set $TERM in your shell to
"xterm-8bit" and Vim picks this up and adjusts to the 8-bit setting
automatically.
When Vim receives a response to the |t_RV| (request version) sequence and it
starts with CSI, it assumes that the terminal is in 8-bit mode and will
convert all key sequences to their 8-bit variants.

==============================================================================
2. Terminal options		*terminal-options* *termcap-options* *E436*

The terminal options can be set just like normal options.  But they are not
shown with the ":set all" command.  Instead use ":set termcap".

It is always possible to change individual strings by setting the
appropriate option.  For example: >
	:set t_ce=^V^[[K	(CTRL-V, <Esc>, [, K)

The options are listed below.  The associated termcap code is always equal to
the last two characters of the option name.  Only one termcap code is
required: Cursor motion, 't_cm'.

The options 't_da', 't_db', 't_ms', 't_xs', 't_xn' represent flags in the
termcap.  When the termcap flag is present, the option will be set to "y".
But any non-empty string means that the flag is set.  An empty string means
that the flag is not set.  't_CS' works like this too, but it isn't a termcap
flag.

OUTPUT CODES						*terminal-output-codes*
	option	meaning	~

	t_AB	set background color (ANSI)			*t_AB* *'t_AB'*
	t_AF	set foreground color (ANSI)			*t_AF* *'t_AF'*
	t_AL	add number of blank lines			*t_AL* *'t_AL'*
	t_al	add new blank line				*t_al* *'t_al'*
	t_bc	backspace character				*t_bc* *'t_bc'*
	t_cd	clear to end of screen				*t_cd* *'t_cd'*
	t_ce	clear to end of line				*t_ce* *'t_ce'*
	t_cl	clear screen					*t_cl* *'t_cl'*
	t_cm	cursor motion (required!)		  *E437* *t_cm* *'t_cm'*
	t_Co	number of colors				*t_Co* *'t_Co'*
	t_CS	if non-empty, cursor relative to scroll region	*t_CS* *'t_CS'*
	t_cs	define scrolling region				*t_cs* *'t_cs'*
	t_CV	define vertical scrolling region		*t_CV* *'t_CV'*
	t_da	if non-empty, lines from above scroll down	*t_da* *'t_da'*
	t_db	if non-empty, lines from below scroll up	*t_db* *'t_db'*
	t_DL	delete number of lines				*t_DL* *'t_DL'*
	t_dl	delete line					*t_dl* *'t_dl'*
	t_fs	set window title end (from status line)		*t_fs* *'t_fs'*
	t_ke	exit "keypad transmit" mode			*t_ke* *'t_ke'*
	t_ks	start "keypad transmit" mode			*t_ks* *'t_ks'*
	t_le	move cursor one char left			*t_le* *'t_le'*
	t_mb	blinking mode					*t_mb* *'t_mb'*
	t_md	bold mode					*t_md* *'t_md'*
	t_me	Normal mode (undoes t_mr, t_mb, t_md and color)	*t_me* *'t_me'*
	t_mr	reverse (invert) mode				*t_mr* *'t_mr'*
								*t_ms* *'t_ms'*
	t_ms	if non-empty, cursor can be moved in standout/inverse mode
	t_nd	non destructive space character			*t_nd* *'t_nd'*
	t_op	reset to original color pair			*t_op* *'t_op'*
	t_RI	cursor number of chars right			*t_RI* *'t_RI'*
	t_Sb	set background color				*t_Sb* *'t_Sb'*
	t_Sf	set foreground color				*t_Sf* *'t_Sf'*
	t_se	standout end					*t_se* *'t_se'*
	t_so	standout mode					*t_so* *'t_so'*
	t_sr	scroll reverse (backward)			*t_sr* *'t_sr'*
	t_te	end of "termcap" mode				*t_te* *'t_te'*
	t_ti	put terminal into "termcap" mode		*t_ti* *'t_ti'*
	t_ts	set window title start (to status line)		*t_ts* *'t_ts'*
	t_ue	underline end					*t_ue* *'t_ue'*
	t_us	underline mode					*t_us* *'t_us'*
	t_ut	clearing uses the current background color	*t_ut* *'t_ut'*
	t_vb	visual bell					*t_vb* *'t_vb'*
	t_ve	cursor visible					*t_ve* *'t_ve'*
	t_vi	cursor invisible				*t_vi* *'t_vi'*
	t_vs	cursor very visible (blink)			*t_vs* *'t_vs'*
								*t_xs* *'t_xs'*
	t_xs	if non-empty, standout not erased by overwriting (hpterm)
								*t_xn* *'t_xn'*
	t_xn	if non-empty, writing a character at the last screen cell
		does not cause scrolling
	t_ZH	italics mode					*t_ZH* *'t_ZH'*
	t_ZR	italics end					*t_ZR* *'t_ZR'*

Added by Vim (there are no standard codes for these):
	t_AU	set underline color (ANSI)			*t_AU* *'t_AU'*
	t_Ce	undercurl end					*t_Ce* *'t_Ce'*
	t_Cs	undercurl mode					*t_Cs* *'t_Cs'*
	t_Te	strikethrough end				*t_Te* *'t_Te'*
	t_Ts	strikethrough mode				*t_Ts* *'t_Ts'*
	t_IS	set icon text start				*t_IS* *'t_IS'*
	t_IE	set icon text end				*t_IE* *'t_IE'*
	t_WP	set window position (Y, X) in pixels		*t_WP* *'t_WP'*
	t_GP	get window position (Y, X) in pixels		*t_GP* *'t_GP'*
	t_WS	set window size (height, width in cells)	*t_WS* *'t_WS'*
	t_VS	cursor normally visible (no blink)		*t_VS* *'t_VS'*
	t_SI	start insert mode (bar cursor shape)		*t_SI* *'t_SI'*
	t_SR	start replace mode (underline cursor shape)	*t_SR* *'t_SR'*
	t_EI	end insert or replace mode (block cursor shape)	*t_EI* *'t_EI'*
		|termcap-cursor-shape|
	t_RV	request terminal version string (for xterm)	*t_RV* *'t_RV'*
		The response is stored in |v:termresponse|
		|xterm-8bit| |'ttymouse'| |xterm-codes|
	t_u7	request cursor position (for xterm)		*t_u7* *'t_u7'*
		see |'ambiwidth'|
		The response is stored in |v:termu7resp|
	t_RF	request terminal foreground color		*t_RF* *'t_RF'*
		The response is stored in |v:termrfgresp|
	t_RB	request terminal background color		*t_RB* *'t_RB'*
		The response is stored in |v:termrbgresp|
	t_8f	set foreground color (R, G, B)			*t_8f* *'t_8f'*
		|xterm-true-color|
	t_8b	set background color (R, G, B)			*t_8b* *'t_8b'*
		|xterm-true-color|
	t_8u	set underline color (R, G, B)			*t_8u* *'t_8u'*
	t_BE	enable bracketed paste mode			*t_BE* *'t_BE'*
		|xterm-bracketed-paste|
	t_BD	disable bracketed paste mode			*t_BD* *'t_BD'*
		|xterm-bracketed-paste|
	t_SC	set cursor color start				*t_SC* *'t_SC'*
	t_EC	set cursor color end				*t_EC* *'t_EC'*
	t_SH	set cursor shape				*t_SH* *'t_SH'*
	t_RC	request terminal cursor blinking		*t_RC* *'t_RC'*
		The response is stored in |v:termblinkresp|
	t_RS	request terminal cursor style			*t_RS* *'t_RS'*
		The response is stored in |v:termstyleresp|
	t_ST	save window title to stack			*t_ST* *'t_ST'*
	t_RT	restore window title from stack			*t_RT* *'t_RT'*
	t_Si	save icon text to stack				*t_Si* *'t_Si'*
	t_Ri	restore icon text from stack			*t_Ri* *'t_Ri'*
	t_TE	end of "raw" mode				*t_TE* *'t_TE'*
	t_TI	put terminal into "raw" mode 			*t_TI* *'t_TI'*
	t_fe	enable focus-event tracking 			*t_fe* *'t_fe'*
		|xterm-focus-event|
	t_fd	disable focus-event tracking 			*t_fd* *'t_fd'*
		|xterm-focus-event|

Some codes have a start, middle and end part.  The start and end are defined
by the termcap option, the middle part is text.
	set title text:     t_ts {title text} t_fs
	set icon text:      t_IS {icon text} t_IE
	set cursor color:   t_SC  {color name}  t_EC

t_SH must take one argument:
	0, 1 or none  	blinking block cursor
	2	      	block cursor
	3		blinking underline cursor
	4		underline cursor
	5		blinking vertical bar cursor
	6		vertical bar cursor

t_RS is sent only if the response to t_RV has been received.  It is not used
on Mac OS when Terminal.app could be recognized from the termresponse.


KEY CODES						*terminal-key-codes*
Note: Use the <> form if possible

	option	name		meaning	~

	t_ku	<Up>		arrow up			*t_ku* *'t_ku'*
	t_kd	<Down>		arrow down			*t_kd* *'t_kd'*
	t_kr	<Right>		arrow right			*t_kr* *'t_kr'*
	t_kl	<Left>		arrow left			*t_kl* *'t_kl'*
		<xUp>		alternate arrow up		*<xUp>*
		<xDown>		alternate arrow down		*<xDown>*
		<xRight>	alternate arrow right		*<xRight>*
		<xLeft>		alternate arrow left		*<xLeft>*
		<S-Up>		shift arrow up
		<S-Down>	shift arrow down
	t_%i	<S-Right>	shift arrow right		*t_%i* *'t_%i'*
	t_#4	<S-Left>	shift arrow left		*t_#4* *'t_#4'*
	t_k1	<F1>		function key 1			*t_k1* *'t_k1'*
		<xF1>		alternate F1			*<xF1>*
	t_k2	<F2>		function key 2		*<F2>*	*t_k2* *'t_k2'*
		<xF2>		alternate F2			*<xF2>*
	t_k3	<F3>		function key 3		*<F3>*	*t_k3* *'t_k3'*
		<xF3>		alternate F3			*<xF3>*
	t_k4	<F4>		function key 4		*<F4>*	*t_k4* *'t_k4'*
		<xF4>		alternate F4			*<xF4>*
	t_k5	<F5>		function key 5		*<F5>*	*t_k5* *'t_k5'*
	t_k6	<F6>		function key 6		*<F6>*	*t_k6* *'t_k6'*
	t_k7	<F7>		function key 7		*<F7>*	*t_k7* *'t_k7'*
	t_k8	<F8>		function key 8		*<F8>*	*t_k8* *'t_k8'*
	t_k9	<F9>		function key 9		*<F9>*	*t_k9* *'t_k9'*
	t_k;	<F10>		function key 10		*<F10>*	*t_k;* *'t_k;'*
	t_F1	<F11>		function key 11		*<F11>*	*t_F1* *'t_F1'*
	t_F2	<F12>		function key 12		*<F12>*	*t_F2* *'t_F2'*
	t_F3	<F13>		function key 13		*<F13>*	*t_F3* *'t_F3'*
	t_F4	<F14>