Bash Colors

You can make your BASH script more pretty, by colorizing its output.

Use ANSI escape sequences to set text properties like foreground and background colors.

Colorizing Shell

Use the following template for writing colored text :
echo -e “\e[COLORmSample Text\e[0m”

Option Description
-e Enable interpretation of backslash escapes
\e[ Begin the color modifications
COLORm Color Code + ‘m’ at the end
\e[0m End the color modifications

Examples :

$ echo -e “\e[31mRed Text\e[0m”
Red Text
$ echo -e “\e[42mGreen Background\e[0m”
Green Background

ANSI — Color Escape Codes

Shell scripts commonly use ANSI escape codes for color output :

Color Foreground Code Background Code Sample
Black 30 40
Red 31 41
Green 32 42
Brown 33 43
Blue 34 44
Purple 35 45
Cyan 36 46
Light Gray 37 47

Escape sequence also allows to control the manner in which characters are displayed on the screen :

ANSI Code Description
0 Normal Characters
1 Bold Characters
4 Underlined Characters
5 Blinking Characters
7 Reverse video Characters

Examples :

$ echo -e “\e[1mBold Text\e[0m”
Bold Text
$ echo -e “\e[3mUnderlined Text\e[0m”
Underlined Text

By combining all these escape sequences, we can get more fancy effect.

echo -e “\e[COLOR1;COLOR2mSample Text\e[0m”

There are some differences between colors when combining colors with bold text attribute :

Color Foreground Code Background Code Sample
Dark Gray 1;30 1;40
Light Red 1;31 1;41
Light Green 1;32 1;42
Yellow 1;33 1;43
Light Blue 1;34 1;44
Light Purple 1;35 1;45
Light Cyan 1;36 1;46
White 1;37 1;47

Examples :

$ echo -e “\e[1;34mLight Blue Text\e[0m”
Light Blue Text
$ echo -e “\e[1;33;4;44mYellow Underlined Text on Blue Background\e[0m”
Yellow Underlined Text on Blue Background