How can I change the colors of my xterm using Ansi escape sequences?
Solution 1
ANSI escape sequences consist of a sequence of characters beginning with the Escape character, character 27. The next character is often (though not always) an open-square-bracket: [
The echo command can send escape characters if you specify -e
and use \e
for escape.
The ANSI standard defines 8 colours, plus a bright mode, giving a total of 16 posibilities. The sequence is:
\e[<number>m
Where <number>
is one of:
Foreground:
- 30 Black
- 31 Red
- 32 Green
- 33 Yellow
- 34 Blue
- 35 Magenta
- 36 Cyan
- 37 White
Background:
- 40 Black
- 41 Red
- 42 Green
- 43 Yellow
- 44 Blue
- 45 Magenta
- 46 Cyan
47 White
0 Reset all
- 1 Bold
So to make your foreground red and your background yellow:
$ echo -e "\e[31m\e[43m"
And to enable bold:
$ echo -e "\e[1m"
Of course, you can combine them all together:
$ echo -e "\e[31m\e[43m\e[1m"
There are many many other escape codes for doing other things.
For example - clear the screen and move the cursor to the top-left:
$ echo -e "\e[2J\e[1;1H"
Which is useful when changing the colour:
$ echo -e "\e[31m\e[43m\e[1m\e[2J\e[1;1H"
Which will change the colours, clear the screen, and put the cursor at the top-left. Well, almost the top left. Echo puts a carriage return in, so it moves down a line. You can add -n
to echo to prevent this if you're fussy.
If you mess it all up and can't see what you're typing you can reset the terminal colours to normal by pressing:
Ctrl+v [ 0 m Return
At what you hope is the command prompt. It will whinge about an unknown command, but you will be able to see what you're doing again.
Solution 2
Note that modern Xterms support 32-bit color!
Simple example. To set a nice dark purple background (hey, each to his own) of value #53186f, you do:
echo -ne "\033]11;#53186f\007"
Note that this instantly changes the color of the whole window, not just of the subsequent text. This is especially nice for making a window obviously different after ssh'ing to a server (for example). Put the above 'echo' into your .bashrc and your terminal automatically changes colors when you log into that server (but won't change back when you Ctrl-D out)
You can spend HOURS on the net looking for this - most docs only talk about the original 16 ANSI colors.
Sources: http://www.steike.com/code/xterm-colors/ and http://rtfm.etla.org/xterm/ctlseq.html (look under "Operating System Controls")
Please note: the escape sequence above is valid for XTerms, and may not work for other implementations of "XTerm-like" windowing terminal emulators that may "look" like an XTerm. For example, "gnome-terminal" or "konsole" have different escape sequences, or may not implement color change at all.
Solution 3
Yes. ANSI terminals support ANSI Escape Codes. Each Control Sequence Introducer
(CSI
) Code in the following format:
ESC[<<<CODE>>>
The Ascii character 27
(the ESC
character) or 1b
in hexadecimal, followed by a left square bracket, and then a letter denoting the action to be used.
Note that a list of ;
separated parameters may be supplied directly before the <<<CODE>>>
parameter.
Now, colors use a subset of CSI
codes, the Select Graphic Rendition
codes. These are in the form:
ESC[<<<SGR>>>m
The SGR
code is passed as a parameter the CSI
. Relevant to your question are the SGR
codes 30-49. Codes 30-39 set the foreground color. Codes 40-49 set the background color.
30 - Foreground Black
31 - Foreground Red
32 - Foreground Green
33 - Foreground Yellow
34 - Foreground Blue
35 - Foreground Magenta
36 - Foreground Cyan
37 - Foreground White
40 - Background Black
41 - Background Red
42 - Background Green
43 - Background Yellow
44 - Background Blue
45 - Background Magenta
46 - Background Cyan
47 - Background White
Codes 38 and 48 are special codes. These are the ones which allow you to use RGB values. The format for these is:
ESC[38;2;<r>;<g>;<b>m (Foreground)
ESC[48;2;<r>;<g>;<b>m (Background)
Note: alternative uses include \x1b[<3 or 4>8;5;<web safe color index>m
. With this usage, there is a completely different color encoding. See the link at the top of this answer for more information.
Codes 39 and 49 set the foreground and background colors to their defaults, which are defined on a terminal-by-terminal basis.
In practice, the colors 30-37 40-47 are slightly different than what their labels say they are.
0 - Black
1 - Darker Red
2 - Darker Green
3 - Dark/Yellow or Brown (varies between terminals)
4 - Dark Blue
5 - Dark Magenta
6 - Dark Cyan
7 - Light Grey
To get light colors, you use the SGI for bold, 1
. Bold is a misleading name. It does not make the font bold. It actually increases the brightness of the text. With bold applied the colors become:
0 - Dark Grey
1 - Bright Red
2 - Bright Green
3 - Bright Yellow
4 - Bright Blue
5 - Bright Magenta
6 - Bright Cyan
7 - White
Notice: the last two blocks of colors' numbers are are relevant to both fore- and background (<index> + (30 or 40)
).
To remove all styles (back to default/normal mode) use SGR
0.
CSI
codes are not all graphical. For example, ESC[2J
will clear your terminal. ESC[<y>;<x>H
sets the cursor position (1-indexed). See the wikipedia article for more information.
Note: to test these, use echo -e
or printf
.
Solution 4
NOTE: The "^[" is the escape character, and is inserted with a CTRL-V,CTRL-[, and ^G is a bell character, inserted with CTRL-V,CTRL-G
The following block is in my .bash_profile and ensures that my xterms on this system are ALWAYS white-on-black, even after logging onto another system that may have changed my colors.
perl -e '$e=chr(27);print "${e}[37m ${e}[40m ${e}[2J ${e}[1;1H";'
export PS1='^[[37m^[]0;${HOST}: ${PWD}^G^[[40m${USER}@${HOST}:${PWD}
--> '
Comments
-
Nathan Fellman over 1 year
I would like to change the colors (background, font, foreground) of my xterm from the commandline. I've heard that this can be done using ANSI escape sequences.
If this is possible:
- How is it done?
- Can I use color names or must I use their RGB codes?
-
Admin over 3 years
echo -ne "\033]11;rgb:53/18/6f\007"
-
Nathan Fellman about 13 yearscan I use color names instead of color codes?
-
FJ de Brienne about 13 yearsNo, but you can assign the colour codes to variables. FGRED=31; echo -e "\e[${FGRED}m"
-
Richard over 11 yearsThis is not working for me, it echos a blank line with no observable change in the terminal.
-
Andreas Spindler about 11 yearsIt should be noted, however, that multiple color code numbers can be separated by ";". So to make your foreground red and your background yellow you can also use the shorter:
echo -ne '\e[31;43m'
(instead of the aboveecho -e "\e[31m\e[43m"
). -
vol7ron about 11 yearsThis worked for me, whereas the others did not -- very helpful, thx
-
Rob I about 11 years+1 changes the window background, and allows color names - like "green" instead of "#00ff00".
-
Breno Macena almost 10 yearsHow do I change the color of the cursor to 34 Blue?
-
jiggunjer about 7 yearshow is #53186f 32-bit colors. I count 24 bits...
-
wjandrea almost 7 yearsDoes anyone know how to accomplish the same thing with gnome-terminal?
-
SlySven over 5 yearsTechnically those
ESC[38
...m
andESC[38
...m
can/should (depends on your source of information - the ultimate one being, I believe, itu.int/rec/T-REC-T.416-199303-I ) should use the, otherwise reserved, character:
(to separate the parameter elements) so that the;
is used only between complete parameter strings - i.e.ESC[38;2;150;100;50m
should be writtenESC[38:2::150:100:50m
... -
SlySven over 5 years... unfortunately implementations often forget the color space id between the
2
and the150
- as no-one, that I am aware of, has ever defined what value should go in there the empty default is to be used - but it is often missed off and using only;
as a separator makes it impossible to reliably process the information in accordance with the specification. -
Adam D. over 4 yearsWorks on Kitty (0.13.3) w/TERM=xterm-kitty, and Alacritty (0.3.3) w/TERM=xterm-256color. It doesn't seem to work under TMUX.
-
hackerb9 over 4 yearsI suggest improving this answer so that it tells how to also set the foreground and cursor colors. Change the 11 to 10 for fg, 12 for cursor.