runtime/doc/term.txt

*term.txt*      For Vim version 8.0.  Last change: 2016 Sep 02


		  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-DOS 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' 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' 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>.

						*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.

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.

							*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.
							*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)

{Vi: no terminal options.  You have to exit Vi, edit the termcap entry and
try again}

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
	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	out of "termcap" mode				*t_te* *'t_te'*
	t_ti	put terminal in "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_Ce	undercurl end					*t_Ce* *'t_Ce'*
	t_Cs	undercurl mode					*t_Cs* *'t_Cs'*
	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				*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_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_WS	set window size (height, width) in characters	*t_WS* *'t_WS'*
	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'*
		|xterm-8bit| |v:termresponse| |'ttymouse'| |xterm-codes|
	t_u7	request cursor position (for xterm)		*t_u7* *'t_u7'*
		see |'ambiwidth'|
	t_RB	request terminal background color		*t_RB* *'t_RB'*
	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_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|

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>		function key 14		*<F14>*	*t_F4* *'t_F4'*
	t_F5	<F15>		function key 15		*<F15>*	*t_F5* *'t_F5'*
	t_F6	<F16>		function key 16		*<F16>*	*t_F6* *'t_F6'*
	t_F7	<F17>		function key 17		*<F17>*	*t_F7* *'t_F7'*
	t_F8	<F18>		function key 18		*<F18>*	*t_F8* *'t_F8'*
	t_F9	<F19>		function key 19		*<F19>*	*t_F9* *'t_F9'*
		<S-F1>		shifted function key 1
		<S-xF1>		alternate <S-F1>		*<S-xF1>*
		<S-F2>		shifted function key 2		*<S-F2>*
		<S-xF2>		alternate <S-F2>		*<S-xF2>*
		<S-F3>		shifted function key 3		*<S-F3>*
		<S-xF3>		alternate <S-F3>		*<S-xF3>*
		<S-F4>		shifted function key 4		*<S-F4>*
		<S-xF4>		alternate <S-F4>		*<S-xF4>*
		<S-F5>		shifted function key 5		*<S-F5>*
		<S-F6>		shifted function key 6		*<S-F6>*
		<S-F7>		shifted function key 7		*<S-F7>*
		<S-F8>		shifted function key 8		*<S-F8>*
		<S-F9>		shifted function key 9		*<S-F9>*
		<S-F10>		shifted function key 10		*<S-F10>*
		<S-F11>		shifted function key 11		*<S-F11>*
		<S-F12>		shifted function key 12		*<S-F12>*
	t_%1	<Help>		help key			*t_%1* *'t_%1'*
	t_&8	<Undo>		undo key			*t_&8* *'t_&8'*
	t_kI	<Insert>	insert key			*t_kI* *'t_kI'*
	t_kD	<Del>		delete key			*t_kD* *'t_kD'*
	t_kb	<BS>		backspace key			*t_kb* *'t_kb'*
	t_kB	<S-Tab>		back-tab (shift-tab)  *<S-Tab>*	*t_kB* *'t_kB'*
	t_kh	<Home>		home key			*t_kh* *'t_kh'*
	t_#2	<S-Home>	shifted home key     *<S-Home>*	*t_#2* *'t_#2'*
		<xHome>		alternate home key		*<xHome>*
	t_@7	<End>		end key				*t_@7* *'t_@7'*
	t_*7	<S-End>		shifted end key	*<S-End>* *t_star7* *'t_star7'*
		<xEnd>		alternate end key		*<xEnd>*
	t_kP	<PageUp>	page-up key			*t_kP* *'t_kP'*
	t_kN	<PageDown>	page-down key			*t_kN* *'t_kN'*
	t_K1	<kHome>		keypad home key			*t_K1* *'t_K1'*
	t_K4	<kEnd>		keypad end key			*t_K4* *'t_K4'*
	t_K3	<kPageUp>	keypad page-up key		*t_K3* *'t_K3'*
	t_K5	<kPageDown>	keypad page-down key		*t_K5* *'t_K5'*
	t_K6	<kPlus>		keypad plus key	      *<kPlus>*	*t_K6* *'t_K6'*
	t_K7	<kMinus>	keypad minus key     *<kMinus>*	*t_K7* *'t_K7'*
	t_K8	<kDivide>	keypad divide	    *<kDivide>*	*t_K8* *'t_K8'*
	t_K9	<kMultiply>	keypad multiply   *<kMultiply>*	*t_K9* *'t_K9'*
	t_KA	<kEnter>	keypad enter key     *<kEnter>*	*t_KA* *'t_KA'*
	t_KB	<kPoint>	keypad decimal point *<kPoint>*	*t_KB* *'t_KB'*
	t_KC	<k0>		keypad 0		 *<k0>*	*t_KC* *'t_KC'*
	t_KD	<k1>		keypad 1		 *<k1>*	*t_KD* *'t_KD'*
	t_KE	<k2>		keypad 2		 *<k2>*	*t_KE* *'t_KE'*
	t_KF	<k3>		keypad 3		 *<k3>*	*t_KF* *'t_KF'*
	t_KG	<k4>		keypad 4		 *<k4>*	*t_KG* *'t_KG'*
	t_KH	<k5>		keypad 5		 *<k5>*	*t_KH* *'t_KH'*
	t_KI	<k6>		keypad 6		 *<k6>*	*t_KI* *'t_KI'*
	t_KJ	<k7>		keypad 7		 *<k7>*	*t_KJ* *'t_KJ'*
	t_KK	<k8>		keypad 8		 *<k8>*	*t_KK* *'t_KK'*
	t_KL	<k9>		keypad 9		 *<k9>*	*t_KL* *'t_KL'*
		<Mouse>		leader of mouse code		*<Mouse>*
	t_PS	start of brackted paste |xterm-bracketed-paste|   *t_PS* 't_PS'
	t_PE	end of bracketed paste |xterm-bracketed-paste|    *t_PE* 't_PE'

Note about t_so and t_mr: When the termcap entry "so" is not present the
entry for "mr" is used.  And vice versa.  The same is done for "se" and "me".
If your terminal supports both inversion and standout mode, you can see two
different modes.  If your terminal supports only one of the modes, both will
look the same.

							*keypad-comma*
The keypad keys, when they are not mapped, behave like the equivalent normal
key.  There is one exception: if you have a comma on the keypad instead of a
decimal point, Vim will use a dot anyway.  Use these mappings to fix that: >
	:noremap <kPoint> ,
	:noremap! <kPoint> ,
<							*xterm-codes*
There is a special trick to obtain the key codes which currently only works
for xterm.  When |t_RV| is defined and a response is received which indicates
an xterm with patchlevel 141 or higher, Vim uses special escape sequences to
request the key codes directly from the xterm.  The responses are used to
adjust the various t_ codes.  This avoids the problem that the xterm can
produce different codes, depending on the mode it is in (8-bit, VT102,
VT220, etc.).  The result is that codes like <xF1> are no longer needed.
Note: This is only done on startup.  If the xterm options are changed after
Vim has started, the escape sequences may not be recognized anymore.

							*xterm-true-color*
Vim supports using true colors in the terminal (taken from |highlight-guifg|
and |highlight-guibg|), given that the terminal supports this. To make this 
work the 'termguicolors' option needs to be set.
See https://gist.github.com/XVilka/8346728 for a list of terminals that
support true colors.

Sometimes setting 'termguicolors' is not enough and one has to set the |t_8f|
and |t_8b| options explicitly. Default values of these options are
"^[[38;2;%lu;%lu;%lum" and "^[[48;2;%lu;%lu;%lum" respectively, but it is only
set when `$TERM` is `xterm`. Some terminals accept the same sequences, but
with all semicolons replaced by colons (this is actually more compatible, but
less widely supported): >
	 let &t_8f = "\<Esc>[38:2:%lu:%lu:%lum"
	 let &t_8b = "\<Esc>[48:2:%lu:%lu:%lum"

These options contain printf strings, with |printf()| (actually, its C
equivalent hence `l` modifier) invoked with the t_ option value and three
unsigned long integers that may have any value between 0 and 255 (inclusive)
representing red, green and blue colors respectively.

							*xterm-resize*
Window resizing with xterm only works if the allowWindowOps resource is
enabled.  On some systems and versions of xterm it's disabled by default
because someone thought it would be a security issue.  It's not clear if this
is actually the case.

To overrule the default, put this line in your ~/.Xdefaults or
~/.Xresources:
>
	XTerm*allowWindowOps: 		true

And run "xrdb -merge .Xresources" to make it effective.  You can check the
value with the context menu (right mouse button while CTRL key is pressed),
there should be a tick at allow-window-ops.

							*termcap-colors*
Note about colors: The 't_Co' option tells Vim the number of colors available.
When it is non-zero, the 't_AB' and 't_AF' options are used to set the color.
If one of these is not available, 't_Sb' and 't_Sf' are used.  't_me' is used
to reset to the default colors.

				*termcap-cursor-shape* *termcap-cursor-color*
When Vim enters Insert mode the 't_SI' escape sequence is sent.  When Vim
enters Replace mode the 't_SR' escape sequence is sent if it is set, otherwise
't_SI' is sent.  When leaving Insert mode or Replace mode 't_EI' is used. This
can be used to change the shape or color of the cursor in Insert or Replace
mode. These are not standard termcap/terminfo entries, you need to set them
yourself.
Example for an xterm, this changes the color of the cursor: >
    if &term =~ "xterm"
	let &t_SI = "\<Esc>]12;purple\x7"
	let &t_SR = "\<Esc>]12;red\x7"
	let &t_EI = "\<Esc>]12;blue\x7"
    endif
NOTE: When Vim exits the shape for Normal mode will remain.  The shape from
before Vim started will not be restored.
{not available when compiled without the |+cursorshape| feature}

							*termcap-title*
The 't_ts' and 't_fs' options are used to set the window title if the terminal
allows title setting via sending strings.  They are sent before and after the
title string, respectively.  Similar 't_IS' and 't_IE'  are used to set the
icon text.  These are Vim-internal extensions of the Unix termcap, so they
cannot be obtained from an external termcap.  However, the builtin termcap
contains suitable entries for xterm and iris-ansi, so you don't need to set
them here.
							*hpterm*
If inversion or other highlighting does not work correctly, try setting the
't_xs' option to a non-empty string.  This makes the 't_ce' code be used to
remove highlighting from a line.  This is required for "hpterm".  Setting the
'weirdinvert' option has the same effect as making 't_xs' non-empty, and vice
versa.

							*scroll-region*
Some termcaps do not include an entry for 'cs' (scroll region), although the
terminal does support it.  For example: xterm on a Sun.  You can use the
builtin_xterm or define t_cs yourself.  For example: >
	:set t_cs=^V^[[%i%d;%dr
Where ^V is CTRL-V and ^[ is <Esc>.

The vertical scroll region t_CV is not a standard termcap code.  Vim uses it
internally in the GUI.  But it can also be defined for a terminal, if you can
find one that supports it.  The two arguments are the left and right column of
the region which to restrict the scrolling to.  Just like t_cs defines the top
and bottom lines.  Defining t_CV will make scrolling in vertically split
windows a lot faster.  Don't set t_CV when t_da or t_db is set (text isn't
cleared when scrolling).

Unfortunately it is not possible to deduce from the termcap how cursor
positioning should be done when using a scrolling region: Relative to the
beginning of the screen or relative to the beginning of the scrolling region.
Most terminals use the first method.  A known exception is the MS-DOS console
(pcterm).  The 't_CS' option should be set to any string when cursor
positioning is relative to the start of the scrolling region.  It should be
set to an empty string otherwise.  It defaults to "yes" when 'term' is
"pcterm".

Note for xterm users: The shifted cursor keys normally don't work.  You can
	make them work with the xmodmap command and some mappings in Vim.

	Give these commands in the xterm:
		xmodmap -e "keysym Up = Up F13"
		xmodmap -e "keysym Down = Down F16"
		xmodmap -e "keysym Left = Left F18"
		xmodmap -e "keysym Right = Right F19"

	And use these mappings in Vim:
		:map <t_F3> <S-Up>
		:map! <t_F3> <S-Up>
		:map <t_F6> <S-Down>
		:map! <t_F6> <S-Down>
		:map <t_F8> <S-Left>
		:map! <t_F8> <S-Left>
		:map <t_F9> <S-Right>
		:map! <t_F9> <S-Right>

Instead of, say, <S-Up> you can use any other command that you want to use the
shift-cursor-up key for.  (Note: To help people that have a Sun keyboard with
left side keys F14 is not used because it is confused with the undo key; F15
is not used, because it does a window-to-front; F17 is not used, because it
closes the window.  On other systems you can probably use them.)

==============================================================================
3. Window size						*window-size*

[This is about the size of the whole window Vim is using, not a window that is
created with the ":split" command.]

If you are running Vim on an Amiga and the terminal name is "amiga" or
"builtin_amiga", the amiga-specific window resizing will be enabled.  On Unix
systems three methods are tried to get the window size:

- an ioctl call (TIOCGSIZE or TIOCGWINSZ, depends on your system)
- the environment variables "LINES" and "COLUMNS"
- from the termcap entries "li" and "co"

If everything fails a default size of 24 lines and 80 columns is assumed.  If
a window-resize signal is received the size will be set again.  If the window
size is wrong you can use the 'lines' and 'columns' options to set the
correct values.

One command can be used to set the screen size:

						*:mod* *:mode* *E359*
:mod[e] [mode]

Without argument this only detects the screen size and redraws the screen.
With MS-DOS it is possible to switch screen mode.  [mode] can be one of these
values:
	"bw40"		40 columns black&white
	"c40"		40 columns color
	"bw80"		80 columns black&white
	"c80"		80 columns color (most people use this)
	"mono"		80 columns monochrome
	"c4350"		43 or 50 lines EGA/VGA mode
	number		mode number to use, depends on your video card

==============================================================================
4. Slow and fast terminals			*slow-fast-terminal*
						*slow-terminal*

If you have a fast terminal you may like to set the 'ruler' option.  The
cursor position is shown in the status line.  If you are using horizontal
scrolling ('wrap' option off) consider setting 'sidescroll' to a small
number.

If you have a slow terminal you may want to reset the 'showcmd' option.
The command characters will not be shown in the status line.  If the terminal
scrolls very slowly, set the 'scrolljump' to 5 or so.  If the cursor is moved
off the screen (e.g., with "j") Vim will scroll 5 lines at a time.  Another
possibility is to reduce the number of lines that Vim uses with the command
"z{height}<CR>".

If the characters from the terminal are arriving with more than 1 second
between them you might want to set the 'timeout' and/or 'ttimeout' option.
See the "Options" chapter |options|.

If your terminal does not support a scrolling region, but it does support
insert/delete line commands, scrolling with multiple windows may make the
lines jump up and down.  If you don't want this set the 'ttyfast' option.
This will redraw the window instead of scroll it.

If your terminal scrolls very slowly, but redrawing is not slow, set the
'ttyscroll' option to a small number, e.g., 3.  This will make Vim redraw the
screen instead of scrolling, when there are more than 3 lines to be scrolled.

If you are using a color terminal that is slow, use this command: >
	hi NonText cterm=NONE ctermfg=NONE
This avoids that spaces are sent when they have different attributes.  On most
terminals you can't see this anyway.

If you are using Vim over a slow serial line, you might want to try running
Vim inside the "screen" program.  Screen will optimize the terminal I/O quite
a bit.

If you are testing termcap options, but you cannot see what is happening,
you might want to set the 'writedelay' option.  When non-zero, one character
is sent to the terminal at a time (does not work for MS-DOS).  This makes the
screen updating a lot slower, making it possible to see what is happening.

==============================================================================
5. Using the mouse					*mouse-using*

This section is about using the mouse on a terminal or a terminal window.  How
to use the mouse in a GUI window is explained in |gui-mouse|.  For scrolling
with a mouse wheel see |scroll-mouse-wheel|.

Don't forget to enable the mouse with this command: >
	:set mouse=a
Otherwise Vim won't recognize the mouse in all modes (See 'mouse').

Currently the mouse is supported for Unix in an xterm window, in a *BSD
console with |sysmouse|, in a Linux console (with GPM |gpm-mouse|), for
MS-DOS and in a Windows console.
Mouse clicks can be used to position the cursor, select an area and paste.

These characters in the 'mouse' option tell in which situations the mouse will
be used by Vim:
		n	Normal mode
		v	Visual mode
		i	Insert mode
		c	Command-line mode
		h	all previous modes when in a help file
		a	all previous modes
		r	for |hit-enter| prompt

The default for 'mouse' is empty, the mouse is not used.  Normally you would
do: >
	:set mouse=a
to start using the mouse (this is equivalent to setting 'mouse' to "nvich").
If you only want to use the mouse in a few modes or also want to use it for
the two questions you will have to concatenate the letters for those modes.
For example: >
	:set mouse=nv
Will make the mouse work in Normal mode and Visual mode. >
	:set mouse=h
Will make the mouse work in help files only (so you can use "g<LeftMouse>" to
jump to tags).

Whether the selection that is started with the mouse is in Visual mode or
Select mode depends on whether "mouse" is included in the 'selectmode'
option.

In an xterm, with the currently active mode included in the 'mouse' option,
normal mouse clicks are used by Vim, mouse clicks with the shift or ctrl key
pressed go to the xterm.  With the currently active mode not included in
'mouse' all mouse clicks go to the xterm.

							*xterm-clipboard*
In the Athena and Motif GUI versions, when running in a terminal and there is
access to the X-server (DISPLAY is set), the copy and paste will behave like
in the GUI.  If not, the middle mouse button will insert the unnamed register.
In that case, here is how you copy and paste a piece of text:

Copy/paste with the mouse and Visual mode ('mouse' option must be set, see
above):
1. Press left mouse button on first letter of text, move mouse pointer to last
   letter of the text and release the button.  This will start Visual mode and
   highlight the selected area.
2. Press "y" to yank the Visual text in the unnamed register.
3. Click the left mouse button at the insert position.
4. Click the middle mouse button.

Shortcut: If the insert position is on the screen at the same time as the
Visual text, you can do 2, 3 and 4 all in one: Click the middle mouse button
at the insert position.

Note: When the |-X| command line argument is used, Vim will not connect to the
X server and copy/paste to the X clipboard (selection) will not work.  Use the
shift key with the mouse buttons to let the xterm do the selection.

							*xterm-command-server*
When the X-server clipboard is available, the command server described in
|x11-clientserver| can be enabled with the --servername command line argument.

							*xterm-copy-paste*
NOTE: In some (older) xterms, it's not possible to move the cursor past column
95 or 223.  This is an xterm problem, not Vim's.  Get a newer xterm
|color-xterm|.  Also see |'ttymouse'|.

Copy/paste in xterm with (current mode NOT included in 'mouse'):
1. Press left mouse button on first letter of text, move mouse pointer to last
   letter of the text and release the button.
2. Use normal Vim commands to put the cursor at the insert position.
3. Press "a" to start Insert mode.
4. Click the middle mouse button.
5. Press ESC to end Insert mode.
(The same can be done with anything in 'mouse' if you keep the shift key
pressed while using the mouse.)

Note: if you lose the 8th bit when pasting (special characters are translated
into other characters), you may have to do "stty cs8 -istrip -parenb" in your
shell before starting Vim.

Thus in an xterm the shift and ctrl keys cannot be used with the mouse.  Mouse
commands requiring the CTRL modifier can be simulated by typing the "g" key
before using the mouse:
	"g<LeftMouse>"	is "<C-LeftMouse>	(jump to tag under mouse click)
	"g<RightMouse>" is "<C-RightMouse>	("CTRL-T")

					*mouse-mode-table* *mouse-overview*
A short overview of what the mouse buttons do, when 'mousemodel' is "extend":

Normal Mode:
event	      position	   selection	  change  action	~
	       cursor			  window		~
<LeftMouse>     yes	     end	    yes
<C-LeftMouse>   yes	     end	    yes	   "CTRL-]" (2)
<S-LeftMouse>   yes	  no change	    yes	   "*" (2)    *<S-LeftMouse>*
<LeftDrag>      yes	start or extend (1) no		      *<LeftDrag>*
<LeftRelease>   yes	start or extend (1) no
<MiddleMouse>   yes	  if not active     no	   put
<MiddleMouse>   yes	  if active	    no	   yank and put
<RightMouse>    yes	start or extend     yes
<A-RightMouse>  yes start or extend blockw. yes		      *<A-RightMouse>*
<S-RightMouse>  yes	   no change	    yes	   "#" (2)    *<S-RightMouse>*
<C-RightMouse>  no	   no change	    no	   "CTRL-T"
<RightDrag>     yes	    extend	    no		      *<RightDrag>*
<RightRelease>  yes	    extend	    no		      *<RightRelease>*

Insert or Replace Mode:
event	      position	   selection	  change  action	~
	       cursor			  window		~
<LeftMouse>     yes     (cannot be active)  yes
<C-LeftMouse>   yes     (cannot be active)  yes	   "CTRL-O^]" (2)
<S-LeftMouse>   yes     (cannot be active)  yes	   "CTRL-O*" (2)
<LeftDrag>      yes     start or extend (1) no	   like CTRL-O (1)
<LeftRelease>   yes     start or extend (1) no	   like CTRL-O (1)
<MiddleMouse>   no      (cannot be active)  no	   put register
<RightMouse>    yes     start or extend	    yes	   like CTRL-O
<A-RightMouse>  yes start or extend blockw. yes
<S-RightMouse>  yes     (cannot be active)  yes	   "CTRL-O#" (2)
<C-RightMouse>  no	(cannot be active)  no	   "CTRL-O CTRL-T"

In a help window:
event	      position	   selection	  change  action	~
	       cursor			  window		~
<2-LeftMouse>   yes     (cannot be active)  no	   "^]" (jump to help tag)

When 'mousemodel' is "popup", these are different:

Normal Mode:
event	      position	   selection	  change  action	~
	       cursor			  window		~
<S-LeftMouse>	yes	start or extend (1) no
<A-LeftMouse>   yes start or extend blockw. no		      *<A-LeftMouse>*
<RightMouse>	no	popup menu	    no

Insert or Replace Mode:
event	      position	   selection	  change  action	~
	       cursor			  window		~
<S-LeftMouse>   yes     start or extend (1) no	   like CTRL-O (1)
<A-LeftMouse>   yes start or extend blockw. no
<RightMouse>    no	popup menu	    no

(1) only if mouse pointer moved since press
(2) only if click is in same buffer

Clicking the left mouse button causes the cursor to be positioned.  If the
click is in another window that window is made the active window.  When
editing the command-line the cursor can only be positioned on the
command-line.  When in Insert mode Vim remains in Insert mode.  If 'scrolloff'
is set, and the cursor is positioned within 'scrolloff' lines from the window
border, the text is scrolled.

A selection can be started by pressing the left mouse button on the first
character, moving the mouse to the last character, then releasing the mouse
button.  You will not always see the selection until you release the button,
only in some versions (GUI, MS-DOS, WIN32) will the dragging be shown
immediately.  Note that you can make the text scroll by moving the mouse at
least one character in the first/last line in the window when 'scrolloff' is
non-zero.

In Normal, Visual and Select mode clicking the right mouse button causes the
Visual area to be extended.  When 'mousemodel' is "popup", the left button has
to be used while keeping the shift key pressed.  When clicking in a window
which is editing another buffer, the Visual or Select mode is stopped.

In Normal, Visual and Select mode clicking the right mouse button with the alt
key pressed causes the Visual area to become blockwise.  When 'mousemodel' is
"popup" the left button has to be used with the alt key.  Note that this won't
work on systems where the window manager consumes the mouse events when the
alt key is pressed (it may move the window).

							*double-click*
Double, triple and quadruple clicks are supported when the GUI is active,
for MS-DOS and Win32, and for an xterm (if the gettimeofday() function is
available).  For selecting text, extra clicks extend the selection:
	click		select ~
	double		word or % match		*<2-LeftMouse>*
	triple		line			*<3-LeftMouse>*
	quadruple	rectangular block	*<4-LeftMouse>*
Exception: In a Help window a double click jumps to help for the word that is
clicked on.
A double click on a word selects that word.  'iskeyword' is used to specify
which characters are included in a word.  A double click on a character
that has a match selects until that match (like using "v%").  If the match is
an #if/#else/#endif block, the selection becomes linewise.
For MS-DOS and xterm the time for double clicking can be set with the
'mousetime' option.  For the other systems this time is defined outside of
Vim.
An example, for using a double click to jump to the tag under the cursor: >
	:map <2-LeftMouse> :exe "tag ". expand("<cword>")<CR>

Dragging the mouse with a double click (button-down, button-up, button-down
and then drag) will result in whole words to be selected.  This continues
until the button is released, at which point the selection is per character
again.

							*gpm-mouse*
The GPM mouse is only supported when the |+mouse_gpm| feature was enabled at
compile time.  The GPM mouse driver (Linux console) does not support quadruple
clicks.

In Insert mode, when a selection is started, Vim goes into Normal mode
temporarily.  When Visual or Select mode ends, it returns to Insert mode.
This is like using CTRL-O in Insert mode.  Select mode is used when the
'selectmode' option contains "mouse".
							*sysmouse*
The sysmouse is only supported when the |+mouse_sysmouse| feature was enabled
at compile time.  The sysmouse driver (*BSD console) does not support keyboard
modifiers.

							*drag-status-line*
When working with several windows, the size of the windows can be changed by
dragging the status line with the mouse.  Point the mouse at a status line,
press the left button, move the mouse to the new position of the status line,
release the button.  Just clicking the mouse in a status line makes that window
the current window, without moving the cursor.  If by selecting a window it
will change position or size, the dragging of the status line will look
confusing, but it will work (just try it).

					*<MiddleRelease>* *<MiddleDrag>*
Mouse clicks can be mapped.  The codes for mouse clicks are:
     code	    mouse button	      normal action	~
 <LeftMouse>	 left pressed		    set cursor position
 <LeftDrag>	 left moved while pressed   extend selection
 <LeftRelease>	 left released		    set selection end
 <MiddleMouse>	 middle pressed		    paste text at cursor position
 <MiddleDrag>	 middle moved while pressed -
 <MiddleRelease> middle released	    -
 <RightMouse>	 right pressed		    extend selection
 <RightDrag>	 right moved while pressed  extend selection
 <RightRelease>  right released		    set selection end
 <X1Mouse>	 X1 button pressed	    -			*X1Mouse*
 <X1Drag>	 X1 moved while pressed	    -			*X1Drag*
 <X1Release>	 X1 button release	    -			*X1Release*
 <X2Mouse>	 X2 button pressed	    -			*X2Mouse*
 <X2Drag>	 X2 moved while pressed     -			*X2Drag*
 <X2Release>	 X2 button release	    -			*X2Release*

The X1 and X2 buttons refer to the extra buttons found on some mice.  The
'Microsoft Explorer' mouse has these buttons available to the right thumb.
Currently X1 and X2 only work on Win32 and X11 environments.

Examples: >
	:noremap <MiddleMouse> <LeftMouse><MiddleMouse>
Paste at the position of the middle mouse button click (otherwise the paste
would be done at the cursor position). >

	:noremap <LeftRelease> <LeftRelease>y
Immediately yank the selection, when using Visual mode.

Note the use of ":noremap" instead of "map" to avoid a recursive mapping.
>
	:map <X1Mouse> <C-O>
	:map <X2Mouse> <C-I>
Map the X1 and X2 buttons to go forwards and backwards in the jump list, see
|CTRL-O| and |CTRL-I|.

						*mouse-swap-buttons*
To swap the meaning of the left and right mouse buttons: >
	:noremap	<LeftMouse>	<RightMouse>
	:noremap	<LeftDrag>	<RightDrag>
	:noremap	<LeftRelease>	<RightRelease>
	:noremap	<RightMouse>	<LeftMouse>
	:noremap	<RightDrag>	<LeftDrag>
	:noremap	<RightRelease>	<LeftRelease>
	:noremap	g<LeftMouse>	<C-RightMouse>
	:noremap	g<RightMouse>	<C-LeftMouse>
	:noremap!	<LeftMouse>	<RightMouse>
	:noremap!	<LeftDrag>	<RightDrag>
	:noremap!	<LeftRelease>	<RightRelease>
	:noremap!	<RightMouse>	<LeftMouse>
	:noremap!	<RightDrag>	<LeftDrag>
	:noremap!	<RightRelease>	<LeftRelease>
<
 vim:tw=78:ts=8:ft=help:norl: