linux - how - shell script color output




How to change the output color of echo in Linux (15)

For readability

If you want to improve the readability of the code, you can echo the string first then add the color later by using sed:

echo 'Hello World!' | sed $'s/World/\e[1m&\e[0m/' 

I am trying to print a text in the terminal using echo command.

I want to print the text in a red color. How can I do that?


some variables that you can use:

# Reset
Color_Off='\033[0m'       # Text Reset

# Regular Colors
Black='\033[0;30m'        # Black
Red='\033[0;31m'          # Red
Green='\033[0;32m'        # Green
Yellow='\033[0;33m'       # Yellow
Blue='\033[0;34m'         # Blue
Purple='\033[0;35m'       # Purple
Cyan='\033[0;36m'         # Cyan
White='\033[0;37m'        # White

# Bold
BBlack='\033[1;30m'       # Black
BRed='\033[1;31m'         # Red
BGreen='\033[1;32m'       # Green
BYellow='\033[1;33m'      # Yellow
BBlue='\033[1;34m'        # Blue
BPurple='\033[1;35m'      # Purple
BCyan='\033[1;36m'        # Cyan
BWhite='\033[1;37m'       # White

# Underline
UBlack='\033[4;30m'       # Black
URed='\033[4;31m'         # Red
UGreen='\033[4;32m'       # Green
UYellow='\033[4;33m'      # Yellow
UBlue='\033[4;34m'        # Blue
UPurple='\033[4;35m'      # Purple
UCyan='\033[4;36m'        # Cyan
UWhite='\033[4;37m'       # White

# Background
On_Black='\033[40m'       # Black
On_Red='\033[41m'         # Red
On_Green='\033[42m'       # Green
On_Yellow='\033[43m'      # Yellow
On_Blue='\033[44m'        # Blue
On_Purple='\033[45m'      # Purple
On_Cyan='\033[46m'        # Cyan
On_White='\033[47m'       # White

# High Intensity
IBlack='\033[0;90m'       # Black
IRed='\033[0;91m'         # Red
IGreen='\033[0;92m'       # Green
IYellow='\033[0;93m'      # Yellow
IBlue='\033[0;94m'        # Blue
IPurple='\033[0;95m'      # Purple
ICyan='\033[0;96m'        # Cyan
IWhite='\033[0;97m'       # White

# Bold High Intensity
BIBlack='\033[1;90m'      # Black
BIRed='\033[1;91m'        # Red
BIGreen='\033[1;92m'      # Green
BIYellow='\033[1;93m'     # Yellow
BIBlue='\033[1;94m'       # Blue
BIPurple='\033[1;95m'     # Purple
BICyan='\033[1;96m'       # Cyan
BIWhite='\033[1;97m'      # White

# High Intensity backgrounds
On_IBlack='\033[0;100m'   # Black
On_IRed='\033[0;101m'     # Red
On_IGreen='\033[0;102m'   # Green
On_IYellow='\033[0;103m'  # Yellow
On_IBlue='\033[0;104m'    # Blue
On_IPurple='\033[0;105m'  # Purple
On_ICyan='\033[0;106m'    # Cyan
On_IWhite='\033[0;107m'   # White

the escape character in bash, hex and octal respectively:

|       | bash  | hex    | octal   | NOTE                         |
|-------+-------+--------+---------+------------------------------|
| start | \e    | \x1b   | \033    |                              |
| start | \E    | \x1B   | -       | x cannot be capital          |
| end   | \e[0m | \x1m0m | \033[0m |                              |
| end   | \e[m  | \x1b[m | \033[m  | 0 is appended if you omit it |
|       |       |        |         |                              |

short example:

| color       | bash         | hex            | octal          | NOTE                                  |
|-------------+--------------+----------------+----------------+---------------------------------------|
| start green | \e[32m<text> | \x1b[32m<text> | \033[32m<text> | m is NOT optional                     |
| reset       | <text>\e[0m  | <text>\1xb[0m  | <text>\033[om  | o is optional (do it as best practice |
|             |              |                |                |                                       |

bash exception:

If you are going to use these codes in your special bash variables

  • PS0
  • PS1
  • PS2 (= this is for prompting)
  • PS4

you should add extra escape characters so that bash can interpret them correctly. Without this adding extra escape characters it works but you will face problems when you use Ctrl + r for search in your history.

exception rule for bash

You should add \[ before any starting ANSI code and add \] after any ending ones.
Example:
in regular usage: \033[32mThis is in green\033[0m
for PS0/1/2/4: \[\033[32m\]This is in green\[\033[m\]

\[ is for start of a sequence of non-printable characters
\] is for end of a sequence of non-printable characters

Tip: for memorize it you can first add \[\] and then put your ANSI code between them:
- \[start-ANSI-code\]
- \[end-ANSI-code\]

type of color sequence:

  1. 3/4 bit
  2. 8 bit
  3. 24 bit

Before diving into these colors, you should know about 4 modes with these codes:

1. color-mode

It modifies the style of color NOT text. For example make the color bright or darker.

  • 0 reset
  • 1; lighter than normal
  • 2; darker than normal

This mode is not supported widely. It is fully support on Gnome-Terminal.

2. text-mode

This mode is for modifying the style of text NOT color.

  • 3; italic
  • 4; underline
  • 5; blinking (slow)
  • 6; blinking (fast)
  • 7; reverse
  • 8; hide
  • 9; cross-out

and are almost supported.
For example KDE-Konsole supports 5; but Gnome-Terminal does not and Gnome supports 8; but KDE does not.

3. foreground mode

This mode is for colorizing the foreground.

4. background mode

This mode is for colorizing the background.

The below table shows a summary of 3/4 bit version of ANSI-color

|------------+----------+---------+-------+------------------+------------------------------+--------------------------------------|
| color-mode | octal    | hex     | bash  | description      | example (= in octal)         | NOTE                                 |
|------------+----------+---------+-------+------------------+------------------------------+--------------------------------------|
|          0 | \033[0m  | \x1b[0m | \e[0m | reset any affect | echo -e "\033[0m"            | 0m equals to m                       |
|          1 | \033[1m  |         |       | light (= bright) | echo -e "\033[1m####\033[m"  | -                                    |
|          2 | \033[2m  |         |       | dark (= fade)    | echo -e "\033[2m####\033[m"  | -                                    |
|------------+----------+---------+-------+------------------+------------------------------+--------------------------------------|
|  text-mode | ~        |         |       | ~                | ~                            | ~                                    |
|------------+----------+---------+-------+------------------+------------------------------+--------------------------------------|
|          3 | \033[3m  |         |       | italic           | echo -e "\033[3m####\033[m"  |                                      |
|          4 | \033[4m  |         |       | underline        | echo -e "\033[4m####\033[m"  |                                      |
|          5 | \033[5m  |         |       | blink (slow)     | echo -e "\033[3m####\033[m"  |                                      |
|          6 | \033[6m  |         |       | blink (fast)     | ?                            | not wildly support                   |
|          7 | \003[7m  |         |       | reverse          | echo -e "\033[7m####\033[m"  | it affects the background/foreground |
|          8 | \033[8m  |         |       | hide             | echo -e "\033[8m####\033[m"  | it affects the background/foreground |
|          9 | \033[9m  |         |       | cross            | echo -e "\033[9m####\033[m"  |                                      |
|------------+----------+---------+-------+------------------+------------------------------+--------------------------------------|
| foreground | ~        |         |       | ~                | ~                            | ~                                    |
|------------+----------+---------+-------+------------------+------------------------------+--------------------------------------|
|         30 | \033[30m |         |       | black            | echo -e "\033[30m####\033[m" |                                      |
|         31 | \033[31m |         |       | red              | echo -e "\033[31m####\033[m" |                                      |
|         32 | \033[32m |         |       | green            | echo -e "\033[32m####\033[m" |                                      |
|         33 | \033[32m |         |       | yellow           | echo -e "\033[33m####\033[m" |                                      |
|         34 | \033[32m |         |       | blue             | echo -e "\033[34m####\033[m" |                                      |
|         35 | \033[32m |         |       | purple           | echo -e "\033[35m####\033[m" | real name: magenta = reddish-purple  |
|         36 | \033[32m |         |       | cyan             | echo -e "\033[36m####\033[m" |                                      |
|         37 | \033[32m |         |       | white            | echo -e "\033[37m####\033[m" |                                      |
|------------+----------+---------+-------+------------------+------------------------------+--------------------------------------|
|         38 | 8/24     |                    This is for special use of 8-bit or 24-bit                                            |
|------------+----------+---------+-------+------------------+------------------------------+--------------------------------------|
| background | ~        |         |       | ~                | ~                            | ~                                    |
|------------+----------+---------+-------+------------------+------------------------------+--------------------------------------|
|         40 | \033[40m |         |       | black            | echo -e "\033[40m####\033[m" |                                      |
|         41 | \033[41m |         |       | red              | echo -e "\033[41m####\033[m" |                                      |
|         42 | \033[42m |         |       | green            | echo -e "\033[42m####\033[m" |                                      |
|         43 | \033[43m |         |       | yellow           | echo -e "\033[43m####\033[m" |                                      |
|         44 | \033[44m |         |       | blue             | echo -e "\033[44m####\033[m" |                                      |
|         45 | \033[45m |         |       | purple           | echo -e "\033[45m####\033[m" | real name: magenta = reddish-purple  |
|         46 | \033[46m |         |       | cyan             | echo -e "\033[46m####\033[m" |                                      |
|         47 | \033[47m |         |       | white            | echo -e "\033[47m####\033[m" |                                      |
|------------+----------+---------+-------+------------------+------------------------------+--------------------------------------|
|         48 | 8/24     |                    This is for special use of 8-bit or 24-bit                                            |                                                                                       |
|------------+----------+---------+-------+------------------+------------------------------+--------------------------------------|

The below table shows a summary of 8 bit version of ANSI-color

|------------+-----------+-----------+---------+------------------+------------------------------------+-------------------------|
| foreground | octal     | hex       | bash    | description      | example                            | NOTE                    |
|------------+-----------+-----------+---------+------------------+------------------------------------+-------------------------|
|        0-7 | \033[38;5 | \x1b[38;5 | \e[38;5 | standard. normal | echo -e '\033[38;5;1m####\033[m'   |                         |
|       8-15 |           |           |         | standard. light  | echo -e '\033[38;5;9m####\033[m'   |                         |
|     16-231 |           |           |         | more resolution  | echo -e '\033[38;5;45m####\033[m'  | has no specific pattern |
|    232-255 |           |           |         |                  | echo -e '\033[38;5;242m####\033[m' | from black to white     |
|------------+-----------+-----------+---------+------------------+------------------------------------+-------------------------|
| foreground | octal     | hex       | bash    | description      | example                            | NOTE                    |
|------------+-----------+-----------+---------+------------------+------------------------------------+-------------------------|
|        0-7 |           |           |         | standard. normal | echo -e '\033[48;5;1m####\033[m'   |                         |
|       8-15 |           |           |         | standard. light  | echo -e '\033[48;5;9m####\033[m'   |                         |
|     16-231 |           |           |         | more resolution  | echo -e '\033[48;5;45m####\033[m'  |                         |
|    232-255 |           |           |         |                  | echo -e '\033[48;5;242m####\033[m' | from black to white     |
|------------+-----------+-----------+---------+------------------+------------------------------------+-------------------------|

The 8-bit fast test:
for code in {0..255}; do echo -e "\e[38;05;${code}m $code: Test"; done

The below table shows a summary of 24 bit version of ANSI-color

|------------+-----------+-----------+---------+-------------+------------------------------------------+-----------------|
| foreground | octal     | hex       | bash    | description | example                                  | NOTE            |
|------------+-----------+-----------+---------+-------------+------------------------------------------+-----------------|
|      0-255 | \033[38;2 | \x1b[38;2 | \e[38;2 | R = red     | echo -e '\033[38;2;255;0;02m####\033[m'  | R=255, G=0, B=0 |
|      0-255 | \033[38;2 | \x1b[38;2 | \e[38;2 | G = green   | echo -e '\033[38;2;;0;255;02m####\033[m' | R=0, G=255, B=0 |
|      0-255 | \033[38;2 | \x1b[38;2 | \e[38;2 | B = blue    | echo -e '\033[38;2;0;0;2552m####\033[m'  | R=0, G=0, B=255 |
|------------+-----------+-----------+---------+-------------+------------------------------------------+-----------------|
| background | octal     | hex       | bash    | description | example                                  | NOTE            |
|------------+-----------+-----------+---------+-------------+------------------------------------------+-----------------|
|      0-255 | \033[48;2 | \x1b[48;2 | \e[48;2 | R = red     | echo -e '\033[48;2;255;0;02m####\033[m'  | R=255, G=0, B=0 |
|      0-255 | \033[48;2 | \x1b[48;2 | \e[48;2 | G = green   | echo -e '\033[48;2;;0;255;02m####\033[m' | R=0, G=255, B=0 |
|      0-255 | \033[48;2 | \x1b[48;2 | \e[48;2 | B = blue    | echo -e '\033[48;2;0;0;2552m####\033[m'  | R=0, G=0, B=255 |
|------------+-----------+-----------+---------+-------------+------------------------------------------+-----------------|

some screen-shots

foreground 8-bit summary in a .gif

background 8-bit summary in a .gif

color summary with their values

blinking on KDE-Terminal

a simple C code that shows you more

a more advanced tool that I developed to deal with these colors:


color-mode shot

text mode shot

combining is OK

more shots


Tips and Tricks for Advanced Users and Programmers:

Can we use these codes in a programming language?

Yes, you can. I experienced in bash, c, c++, d perl, python

Are they slow down the speed of a program?

I think, NO.

Can we use these on Windows?

3/4-bit Yes, if you compile the code with gcc
some screen-shots on Win-7

How to calculate the length of code?

\033[ = 2, other parts 1

Where can we use these codes?

Anywhere that has a tty interpreter
xterm, gnome-terminal, kde-terminal, mysql-client-CLI and so on.
For example if you want to colorize your output with mysql you can use Perl

#!/usr/bin/perl -n
print "\033[1m\033[31m$1\033[36m$2\033[32m$3\033[33m$4\033[m" while /([|+-]+)|([0-9]+)|([a-zA-Z_]+)|([^\w])/g;

store this code in a file name: pcc (= Perl Colorize Character) and then put the file a in valid PATH then use it anywhere you like.

ls | pcc
df | pcc

inside mysql first register it for pager and then try:

[user2:db2] pager pcc
PAGER set to 'pcc'
[user2:db2] select * from table-name;

It does NOT handle Unicode.

Do these codes only do colorizing?

No, they can do a lot of interesting things. Try:

echo -e '\033[2K'  # clear the screen and do not move the position

or:

echo -e '\033[2J\033[u' # clear the screen and reset the position

There are a lot of beginners that want to clear the screen with system( "clear" ) so you can use this instead of system(3) call

Are they available in Unicode?

Yes. \u001b

Which version of these colors is preferable?

It is easy to use 3/4-bit, but it is much accurate and beautiful to use 24-bit.
If you do not have experience with html so here is a quick tutorial:
24 bits means: 00000000 and 00000000 and 00000000. Each 8-bit is for a specific color.
24..17 is for and 16..9 for and 8..1 for
So in html #FF0000 means and here it is: 255;0;0
in html #00FF00 means which here is: 0;255;0
Does that make sense? what color you want combine it with these three 8-bit values.


reference:
Wikipedia
ANSI escape sequences
tldp.org
tldp.org
misc.flogisoft.com
some blogs/web-pages that I do not remember

badges:


And this what I used to see all combination and decide which reads cool:

for (( i = 0; i < 8; i++ )); do
    for (( j = 0; j < 8; j++ )); do
        printf "$(tput setab $i)$(tput setaf $j)(b=$i, f=$j)$(tput sgr0)\n"
    done
done

Here is a simple little script, I put together recently, that will colorize any piped input instead of using "Toilet".

File: color.bsh

#!/usr/bin/env bash 

## A.M.Danischewski 2015+(c) Free - for (all (uses and 
## modifications)) - except you must keep this notice intact. 

declare INPUT_TXT=""
declare    ADD_LF="\n" 
declare -i DONE=0
declare -r COLOR_NUMBER="${1:-247}"
declare -r ASCII_FG="\\033[38;05;"
declare -r COLOR_OUT="${ASCII_FG}${COLOR_NUMBER}m"

function show_colors() { 
   ## perhaps will add bg 48 to first loop eventually 
 for fgbg in 38; do for color in {0..256} ; do 
 echo -en "\\033[${fgbg};5;${color}m ${color}\t\\033[0m"; 
 (($((${color}+1))%10==0)) && echo; done; echo; done
} 

if [[ ! $# -eq 1 || ${1} =~ ^-. ]]; then 
  show_colors 
  echo " Usage: ${0##*/} <color fg>" 
  echo "  E.g. echo \"Hello world!\" | figlet | ${0##*/} 54" 
else  
 while IFS= read -r PIPED_INPUT || { DONE=1; ADD_LF=""; }; do 
  PIPED_INPUT=$(sed 's#\\#\\\\#g' <<< "${PIPED_INPUT}")
  INPUT_TXT="${INPUT_TXT}${PIPED_INPUT}${ADD_LF}"
  ((${DONE})) && break; 
 done
 echo -en "${COLOR_OUT}${INPUT_TXT}\\033[00m"
fi 

Then call it with color red (196):
$> echo "text you want colored red" | color.bsh 196


I've written swag to achieve just that.

You can just do

pip install swag

Now you can install all the the escape commands as txt files to a given destination via:

swag install -d <colorsdir>

Or even easier via:

swag install

Which will install the colors to ~/.colors.

Either you use them like this:

echo $(cat ~/.colors/blue.txt) This will be blue

Or this way, which I find actually more interesting:

swag print -c red -t underline "I will turn red and be underlined"

Check it out on asciinema!


Just as something a little out there, passing it through grep will highlight it as red (but only red). You can also use named pipes so your string is nearer to the end of the line:

 grep '.*' --color=always <(echo "foobar")

Nobody noticed the usefulness of the ANSI code 7 reversed video.

It stay readable on any terminal schemes colors, black or white backgrounds, or other fancies palettes, by swapping foreground and background colors.

Example, for a red background that works everywhere:

echo -e "\033[31;7mHello world\e[0m";

This is how it looks when changing the terminal built-in schemes:

This is the loop script used for the gif.

for i in {30..49};do echo -e "\033[$i;7mReversed color code $i\e[0m Hello world!";done

See https://en.wikipedia.org/wiki/ANSI_escape_code#SGR_(Select_Graphic_Rendition)_parameters


Thanks to @k-five for this answer

declare -A colors
#curl www.bunlongheng.com/code/colors.png

# Reset
colors[Color_Off]='\033[0m'       # Text Reset

# Regular Colors
colors[Black]='\033[0;30m'        # Black
colors[Red]='\033[0;31m'          # Red
colors[Green]='\033[0;32m'        # Green
colors[Yellow]='\033[0;33m'       # Yellow
colors[Blue]='\033[0;34m'         # Blue
colors[Purple]='\033[0;35m'       # Purple
colors[Cyan]='\033[0;36m'         # Cyan
colors[White]='\033[0;37m'        # White

# Bold
colors[BBlack]='\033[1;30m'       # Black
colors[BRed]='\033[1;31m'         # Red
colors[BGreen]='\033[1;32m'       # Green
colors[BYellow]='\033[1;33m'      # Yellow
colors[BBlue]='\033[1;34m'        # Blue
colors[BPurple]='\033[1;35m'      # Purple
colors[BCyan]='\033[1;36m'        # Cyan
colors[BWhite]='\033[1;37m'       # White

# Underline
colors[UBlack]='\033[4;30m'       # Black
colors[URed]='\033[4;31m'         # Red
colors[UGreen]='\033[4;32m'       # Green
colors[UYellow]='\033[4;33m'      # Yellow
colors[UBlue]='\033[4;34m'        # Blue
colors[UPurple]='\033[4;35m'      # Purple
colors[UCyan]='\033[4;36m'        # Cyan
colors[UWhite]='\033[4;37m'       # White

# Background
colors[On_Black]='\033[40m'       # Black
colors[On_Red]='\033[41m'         # Red
colors[On_Green]='\033[42m'       # Green
colors[On_Yellow]='\033[43m'      # Yellow
colors[On_Blue]='\033[44m'        # Blue
colors[On_Purple]='\033[45m'      # Purple
colors[On_Cyan]='\033[46m'        # Cyan
colors[On_White]='\033[47m'       # White

# High Intensity
colors[IBlack]='\033[0;90m'       # Black
colors[IRed]='\033[0;91m'         # Red
colors[IGreen]='\033[0;92m'       # Green
colors[IYellow]='\033[0;93m'      # Yellow
colors[IBlue]='\033[0;94m'        # Blue
colors[IPurple]='\033[0;95m'      # Purple
colors[ICyan]='\033[0;96m'        # Cyan
colors[IWhite]='\033[0;97m'       # White

# Bold High Intensity
colors[BIBlack]='\033[1;90m'      # Black
colors[BIRed]='\033[1;91m'        # Red
colors[BIGreen]='\033[1;92m'      # Green
colors[BIYellow]='\033[1;93m'     # Yellow
colors[BIBlue]='\033[1;94m'       # Blue
colors[BIPurple]='\033[1;95m'     # Purple
colors[BICyan]='\033[1;96m'       # Cyan
colors[BIWhite]='\033[1;97m'      # White

# High Intensity backgrounds
colors[On_IBlack]='\033[0;100m'   # Black
colors[On_IRed]='\033[0;101m'     # Red
colors[On_IGreen]='\033[0;102m'   # Green
colors[On_IYellow]='\033[0;103m'  # Yellow
colors[On_IBlue]='\033[0;104m'    # Blue
colors[On_IPurple]='\033[0;105m'  # Purple
colors[On_ICyan]='\033[0;106m'    # Cyan
colors[On_IWhite]='\033[0;107m'   # White


color=${colors[$input_color]}
white=${colors[White]}
# echo $white



for i in "${!colors[@]}"
do
  echo -e "$i = ${colors[$i]}I love you$white"
done

Result

Hope this image help you to pick your color for your bash :D


This is the color switch \033[. See history.

Color codes are like 1;32 (Light Green), 0;34 (Blue), 1;34 (Light Blue), etc.

We terminate color sequences with a color switch \033[ and 0m, the no-color code. Just like opening and closing tabs in a markup language.

  SWITCH="\033["
  NORMAL="${SWITCH}0m"
  YELLOW="${SWITCH}1;33m"
  echo "${YELLOW}hello, yellow${NORMAL}"

Simple color echo function solution:

cecho() {
  local code="\033["
  case "$1" in
    black  | bk) color="${code}0;30m";;
    red    |  r) color="${code}1;31m";;
    green  |  g) color="${code}1;32m";;
    yellow |  y) color="${code}1;33m";;
    blue   |  b) color="${code}1;34m";;
    purple |  p) color="${code}1;35m";;
    cyan   |  c) color="${code}1;36m";;
    gray   | gr) color="${code}0;37m";;
    *) local text="$1"
  esac
  [ -z "$text" ] && local text="$color$2${code}0m"
  echo "$text"
}

cecho "Normal"
cecho y "Yellow!"

This question has been answered over and over again :-) but why not.

First using tput is more portable in modern environments than manually injecting ASCII codes through echo -E

Here's a quick bash function:

 say() {
     echo "[email protected]" | sed \
             -e "s/\(\(@\(red\|green\|yellow\|blue\|magenta\|cyan\|white\|reset\|b\|u\)\)\+\)[[]\{2\}\(.*\)[]]\{2\}/\1\[email protected]/g" \
             -e "s/@red/$(tput setaf 1)/g" \
             -e "s/@green/$(tput setaf 2)/g" \
             -e "s/@yellow/$(tput setaf 3)/g" \
             -e "s/@blue/$(tput setaf 4)/g" \
             -e "s/@magenta/$(tput setaf 5)/g" \
             -e "s/@cyan/$(tput setaf 6)/g" \
             -e "s/@white/$(tput setaf 7)/g" \
             -e "s/@reset/$(tput sgr0)/g" \
             -e "s/@b/$(tput bold)/g" \
             -e "s/@u/$(tput sgr 0 1)/g"
  }

Now you can use:

 say @[email protected][[Success]] 

to get:

Notes on portability of tput

First time tput(1) source code was uploaded in September 1986

tput(1) has been available in X/Open curses semantics in 1990s (1997 standard has the semantics mentioned below).

So, it's (quite) ubiquitous.


Use tput to calculate color codes. Avoid using the ANSI escape code (e.g. \E[31;1m for red) because it's less portable. Bash on OS X, for example, does not support it.

BLACK=`tput setaf 0`
RED=`tput setaf 1`
GREEN=`tput setaf 2`
YELLOW=`tput setaf 3`
BLUE=`tput setaf 4`
MAGENTA=`tput setaf 5`
CYAN=`tput setaf 6`
WHITE=`tput setaf 7`

BOLD=`tput bold`
RESET=`tput sgr0`

echo -e "hello ${RED}some red text${RESET} world"

Use tput with the setaf capability and a parameter of 1.

echo "$(tput setaf 1)Hello, world$(tput sgr0)"

You can use these ANSI escape codes:

Black        0;30     Dark Gray     1;30
Red          0;31     Light Red     1;31
Green        0;32     Light Green   1;32
Brown/Orange 0;33     Yellow        1;33
Blue         0;34     Light Blue    1;34
Purple       0;35     Light Purple  1;35
Cyan         0;36     Light Cyan    1;36
Light Gray   0;37     White         1;37

And then use them like this in your script:

#    .---------- constant part!
#    vvvv vvvv-- the code from above
RED='\033[0;31m'
NC='\033[0m' # No Color
printf "I ${RED}love${NC} \n"

which prints love in red.

From @james-lim's comment, if you are using the echo command, be sure to use the -e flag to allow backslash escapes.

# Continued from above example
echo -e "I ${RED}love${NC} "

(don't add "\n" when using echo unless you want to add additional empty line)


You should definitely use tput over raw ANSI control sequences.

Because there's a large number of different terminal control languages, usually a system has an intermediate communication layer. The real codes are looked up in a database for the currently detected terminal type and you give standardized requests to an API or (from the shell) to a command.

One of these commands is tput . tput accepts a set of acronyms called capability names and any parameters, if appropriate, then looks up the correct escape sequences for the detected terminal in the terminfo database and prints the correct codes (the terminal hopefully understands).

from http://wiki.bash-hackers.org/scripting/terminalcodes

That said, I wrote a small helper library called bash-tint, which adds another layer on top of tput, making it even simpler to use (imho):

Example: tint "white(Cyan(T)Magenta(I)Yellow(N)Black(T)) is bold(really) easy to use."

Would give the following result:


red='\e[0;31m'
NC='\e[0m' # No Color
echo -e "${red}Hello ${NC}"

This answer correct, except that the call to colors should not be inside the quotes.

echo -e ${red}"Hello "${NC}

Should do the trick.





terminal-color