Bash/Colors
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"
$ 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"
$ echo -e "\e[1;33;4;44mYellow Underlined Text on Blue Background\e[0m"
Links
Weblinks
- https://www.shellhacks.com/bash-colors/
- https://misc.flogisoft.com/bash/tip_colors_and_formatting
- https://stackoverflow.com/questions/5947742/how-to-change-the-output-color-of-echo-in-linux
Bash tips: Colors and formatting (ANSI/VT100 Control sequences)
The ANSI/VT100 terminals and terminal emulators are not just able to display black and white text ; they can display colors and formatted texts thanks to escape sequences. Those sequences are composed of the Escape character (often represented by “^[” or “<Esc>”) followed by some other characters: “<Esc>[FormatCodem”.
In Bash, the <Esc> character can be obtained with the following syntaxes: * \e
- \033
- \x1B
Examples:
Code (Bash) | Preview |
---|---|
echo -e "\e[31mHello World\e[0m" | "Hello World" |
echo -e "\033[31mHello\e[0m World" | "Hello World" |
NOTE¹: The -e option of the echo command enable the parsing of the escape sequences.
NOTE²: The “\e[0m” sequence removes all attributes (formatting and colors). It can be a good idea to add it at the end of each colored text. ;)
NOTE³: The examples in this page are in Bash but the ANSI/VT100 escape sequences can be used in every programming languages.
Formatting
Here are the most commonly supported control sequences for formatting text. Their support depends on the used terminal (see the compatibility list).
Set
Code | Description | Example | Preview |
---|---|---|---|
1 | Bold/Bright | echo -e "Normal \e[1mBold" | "Normal Bold" |
2 | Dim | echo -e "Normal \e[2mDim" | "Normal Dim" |
4 | Underlined | echo -e "Normal \e[4mUnderlined" | "Normal Underlined" |
5 | Blink 1) | echo -e "Normal \e[5mBlink" | "Normal Blink" |
7 | Reverse (invert the foreground and background colors) | echo -e "Normal \e[7minverted" | "Normal inverted" |
8 | Hidden (useful for passwords) | echo -e "Normal \e[8mHidden" | "Normal Hidden"
|
Reset
Code | Description | Example | Preview |
---|---|---|---|
0 | Reset all attributes | echo -e "\e[0mNormal Text" | "Normal Text" |
21 | Reset bold/bright | echo -e "Normal \e[1mBold \e[21mNormal" | "Normal Bold Normal" |
22 | Reset dim | echo -e "Normal \e[2mDim \e[22mNormal" | "Normal Dim Normal" |
24 | Reset underlined | echo -e "Normal \e[4mUnderlined \e[24mNormal" | "Normal Underlined Normal" |
25 | Reset blink | echo -e "Normal \e[5mBlink \e[25mNormal" | "Normal Blink Normal" |
27 | Reset reverse | echo -e "Normal \e[7minverted \e[27mNormal" | "Normal inverted Normal" |
28 | Reset hidden | echo -e "Normal \e[8mHidden \e[28mNormal" | "Normal Hidden Normal"
|
8/16 Colors
The following colors works with most terminals and terminals emulators 2), see the compatibility list for more informations.
NOTE: The colors can vary depending of the terminal configuration.
Foreground (text)
Code | Color | Example | Preview |
---|---|---|---|
39 | Default foreground color | echo -e "Default \e[39mDefault" | "Default Default" |
30 | Black | echo -e "Default \e[30mBlack" | "Default Black" |
31 | Red | echo -e "Default \e[31mRed" | "Default Red" |
32 | Green | echo -e "Default \e[32mGreen" | "Default Green" |
33 | Yellow | echo -e "Default \e[33mYellow" | "Default Yellow" |
34 | Blue | echo -e "Default \e[34mBlue" | "Default Blue" |
35 | Magenta | echo -e "Default \e[35mMagenta" | "Default Magenta" |
36 | Cyan | echo -e "Default \e[36mCyan" | "Default Cyan" |
37 | Light gray | echo -e "Default \e[37mLight gray" | "Default Light gray" |
90 | Dark gray | echo -e "Default \e[90mDark gray" | "Default Dark gray" |
91 | Light red | echo -e "Default \e[91mLight red" | "Default Light red" |
92 | Light green | echo -e "Default \e[92mLight green" | "Default Light green" |
93 | Light yellow | echo -e "Default \e[93mLight yellow" | "Default Light yellow" |
94 | Light blue | echo -e "Default \e[94mLight blue" | "Default Light blue" |
95 | Light magenta | echo -e "Default \e[95mLight magenta" | "Default Light magenta" |
96 | Light cyan | echo -e "Default \e[96mLight cyan" | "Default Light cyan" |
97 | White | echo -e "Default \e[97mWhite" | "Default White"
|
Background
Code | Color | Example | Preview |
---|---|---|---|
49 | Default background color | echo -e "Default \e[49mDefault" | "Default Default" |
40 | Black | echo -e "Default \e[40mBlack" | "Default Black" |
41 | Red | echo -e "Default \e[41mRed" | "Default Red" |
42 | Green | echo -e "Default \e[42mGreen" | "Default Green" |
43 | Yellow | echo -e "Default \e[43mYellow" | "Default Yellow" |
44 | Blue | echo -e "Default \e[44mBlue" | "Default Blue" |
45 | Magenta | echo -e "Default \e[45mMagenta" | "Default Magenta" |
46 | Cyan | echo -e "Default \e[46mCyan" | "Default Cyan" |
47 | Light gray | echo -e "Default \e[47mLight gray" | "Default Light gray" |
100 | Dark gray | echo -e "Default \e[100mDark gray" | "Default Dark gray" |
101 | Light red | echo -e "Default \e[101mLight red" | "Default Light red" |
102 | Light green | echo -e "Default \e[102mLight green" | "Default Light green" |
103 | Light yellow | echo -e "Default \e[103mLight yellow" | "Default Light yellow" |
104 | Light blue | echo -e "Default \e[104mLight blue" | "Default Light blue" |
105 | Light magenta | echo -e "Default \e[105mLight magenta" | "Default Light magenta" |
106 | Light cyan | echo -e "Default \e[106mLight cyan" | "Default Light cyan" |
107 | White | echo -e "Default \e[107mWhite" | "Default White"
|
88/256 Colors
Some terminals (see the compatibility list) can support 88 or 256 colors. Here are the control sequences that permit you to use them.
NOTE¹: The colors number 256 is only supported by vte (GNOME Terminal, XFCE4 Terminal, Nautilus Terminal, Terminator,…).
NOTE²: The 88-colors terminals (like rxvt) does not have the same color map that the 256-colors terminals. For showing the 88-colors terminals color map, run the “256-colors.sh” script in a 88-colors terminal.
Foreground (text)
For using one of the 256 colors on the foreground (text color), the control sequence is “<Esc>[38;5;ColorNumberm” where ColorNumber is one of the following colors:
"XTerm 256 color list (foreground)"
Examples:
Code (Bash) | Preview |
---|---|
echo -e "\e[38;5;82mHello \e[38;5;198mWorld" | "Hello World" |
for i in {16..21} {21..16} ; do echo -en "\e[38;5;${i}m#\e[0m" ; done ; echo | "Blue gradiant"
|
Background
For using one of the 256 colors on the background, the control sequence is “<Esc>[48;5;ColorNumberm” where ColorNumber is one of the following colors:
"XTerm 256 color list (background)"
Examples:
Code (Bash) | Preview |
---|---|
echo -e "\e[40;38;5;82m Hello \e[30;48;5;82m World \e[0m" | "Hello World" |
for i in {16..21} {21..16} ; do echo -en "\e[48;5;${i}m \e[0m" ; done ; echo | "Blue gradiant"
|
Attributes combination
Terminals allow attribute combinations. The attributes must be separated by a semicolon (“;”).
Examples:
Description | Code (Bash) | Preview |
---|---|---|
Bold + Underlined | echo -e "\e[1;4mBold and Underlined" | "Bold and Underlined" |
Bold + Red forground + Green background | echo -e "\e[1;31;42m Yes it is awful \e[0m" | "Yes it is awful"
|
Terminals compatibility
Terminal | align=center| Formatting | align=center| Colors | Comment | ||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Bold | Dim | Underlined | Blink | invert | Hidden | 8 | 16 | 88 | 256 | ||
aTerm | ok | - | ok | - | ok | - | ok | ~ | - | - | Lighter background instead of blink. |
Eterm | ~ | - | ok | - | ok | - | ok | ~ | - | ok | Lighter color instead of Bold. Lighter background instead of blink. Can overline a text with the “^[[6m” sequence. |
GNOME Terminal | ok | ok | ok | ok | ok | ok | ok | ok | - | ok | Strikeout with the “^[[9m” sequence. |
Guake | ok | ok | ok | ok | ok | ok | ok | ok | - | ok | Strikeout with the “^[[9m” sequence. |
Konsole | ok | - | ok | ok | ok | - | ok | ok | - | ok | |
Nautilus Terminal | ok | ok | ok | ok | ok | ok | ok | ok | - | ok | Strikeout with the “^[[9m” sequence. |
rxvt | ok | - | ok | ~ | ok | - | ok | ok | ok | - | If the background is not set to the default color, Blink make it lighter instead of blinking. Support of italic text with the “^[[3m” sequence. |
Terminator | ok | ok | ok | - | ok | ok | ok | ok | - | ok | Strikeout with the “^[[9m” sequence. |
Tilda | ok | - | ok | ok | ok | - | ok | ok | - | - | Underline instead of Dim. Convert 256-colors in 16-colors. |
XFCE4 Terminal | ok | ok | ok | ok | ok | ok | ok | ok | - | ok | Strikeout with the “^[[9m” sequence. |
XTerm | ok | - | ok | ok | ok | ok | ok | ok | - | ok | |
xvt | ok | - | ok | - | ok | - | - | - | - | - | |
Linux TTY | ok | - | - | - | ok | - | ok | ~ | - | - | Specials colors instead of Dim and Underlined. Lighter background instead of Blink, Bug with 88/256 colors. |
VTE Terminal 3) | ok | ok | ok | ok | ok | ok | ok | ok | - | ok | Strikeout with the “^[[9m” sequence. |
Notations used in the table: * “ok”: Supported by the terminal.
- “~”: Supported in a special way by the terminal.
- “-”: Not supported at all by the terminal.
Demonstration programs
Colors and formatting (16 colors)
"Screenshot of the color_and_formatting.sh script"
The following shell script displays a lot of possible combination of the attributes (but not all, because it uses only one formatting attribute at a time).
256 colors
"Screenshot of the 256-colors.sh script"
The following script display the 256 colors available on some terminals and terminals emulators like XTerm and GNOME Terminal.
Links
- Linux console codes manual (man console_codes)
- XTerm Control Sequences
- Compilation of all escape sequences
- ANSI escape code (Wikipedia)
Does not work with most of the terminal emulators, works in the tty and XTerm.
Some terminals supports only the first 8 colors (30..37 and 40..47), and some others does not support any color at all.
GTK Widget used in GNOME Terminal, Nautilus Terminal, XFCE4 Terminal…