Use Escape Sequence To Set Colors
Nowadays terminal like XTerm & URxvt support 256color. But only the first 16 can be specified using resources currently or other configuration file, the rest can only be shown via command sequences (“escape codes”).
The ECMA-48 SGR sequence ( ESC [ parameters m ) can set foreground & background colors.
Use ‘tput’ To Set Colors
It is generally not good practice to hard-wire terminal controls into programs. Linux supports a terminfo(5) database of terminal capabilities. Rather than emitting console escape sequences by hand, you will almost always want to use a terminfo-aware screen library or utility such as tput(1).
tput command can initialize a terminal or query terminfo database,and could be used in shell conveniently.
Use Escape Sequence to Set Display Attributes
Apart from display foreground & background,the ECMA-48 SGR sequence ( ESC [ parameters m ) can set display attributes.
Use ‘tput’ to Set Display Attributes
Extensive Reading: about setaf/setab & setf/setb
From man terminfo
section Color Handling
Use Escape Sequence To Set Colors
Nowadays terminal like XTerm & URxvt support 256color. But only the first 16 can be specified using resources currently or other configuration file, the rest can only be shown via command sequences (“escape codes”).
The ECMA-48 SGR sequence ( ESC [ parameters m ) can set foreground & background colors.
Parameters For color0 ~ color7:
30 set black foreground 40 set black background
31 set red foreground 41 set red background
32 set green foreground 42 set green background
33 set brown foreground 43 set brown background
34 set blue foreground 44 set blue background
35 set magenta foreground 45 set magenta background
36 set cyan foreground 46 set cyan background
37 set white foreground 47 set white background
for color8 ~ color15,the parameters 90~97 selected the foreground color,
while 100~107 selected the background.(Not Supported On Some Terminals)
For example:
echo -en '\e[30;42mBrighten You Terminal'
It will print the sentence in green foreground and black background.
Apart from ‘\e’,’ESC’ could be written in octal or hexadecimal (e.g.,’\033’ or ‘\x1b’). And printf(shell builtin) can be used instead of echo -en.
To set the foreground/background with color256:
printf '\e[38;5;<256-color-code>m'
printf '\e[48;5;<256-color-code>m'<256-color-code>from 0 to 255.
color16 ~ color231 is 6x6x6=216 colors;
color232 ~ color255 is 24 grayscale colors from black to white.
Just know above,you can make your terminal colorful,like bash prompt PS1&PS2.
Use ‘tput’ To Set Colors
From man console_codes
It is generally not good practice to hard-wire terminal controls into
programs. Linux supports a terminfo(5) database of terminal capabili‐
ties. Rather than emitting console escape sequences by hand, you will
almost always want to use a terminfo-aware screen library or utility
such as ncurses(3), tput(1), or reset(1).
tput command can initialize a terminal or query terminfo database,and could be used in shell conveniently.
To query the terminal support colors’ types:
tput colors
it will output a number like 8,16,88,256.
To change the current foreground/background color on a terminal:
tput setf <256-color-code>
tput setb <256-color-code>
tput setaf <256-color-code>
tput setab <256-color-code>
NOTE:Only tput setab/setaf <256-color-code> can work in XTerm.tput setab/setaf 1 show red,tput setab/setaf 4 show blue,and tput setb/setf 1/4 have the reverse effect.
Be careful to not confuse the two sets of color capabilities; otherwise red/blue will be interchanged on the display.
For example:
tput setaf 255;tput setaf 231;echo 'Brighten You Terminal'
It will print the sentence in color255 as foreground and color231 as background.
Use Escape Sequence to Set Display Attributes
Apart from display foreground & background,the ECMA-48 SGR sequence ( ESC [ parameters m ) can set display attributes.
param result
0 reset all attributes to their defaults
1 set bold
21 set normal intensity (ECMA-48 says "doubly underlined")
2 set half-bright (simulated with color on a color display)
22 set normal intensity
4 set underscore (simulated with color on a color display)
(the colors used to simulate dim or underline are set
using ESC ] ...)
24 underline off
5 set blink
25 blink off
7 set reverse video
27 reverse video off
Use ‘tput’ to Set Display Attributes
Some terminfo string capabilities about display attributes.
Variable String Capname TCapCode Description
enter_blink_mode blink mb turn on blinking
enter_bold_mode bold md turn on bold mode
enter_dim_mode dim mh turn on half-bright mode
enter_italics_mode sitm ZH Enter italic mode
exit_italics_mode ritm ZR End italic mode
enter_reverse_mode rev mr turn on reverse video mode
enter_underline_mode smul us begin underline mode
exit_underline_mode rmul ue exit underline mode
exit_attribute_mode sgr0 me turn off all attributes
For exampletput bold;printf "mBOLD\n“ will have same output with printf "\e[1mBOLD\n".tput sgr0 will have the same affect with printf "\e[0m".