68

I'm trying to add color output to my errors in a bash script that I have running on a mac. The problem is the colors are not working. I created the simplest of scripts to demonstrate that it does not work:

#!/bin/bash

echo -e "\e[1;31m This is red text \e[0m"

However, when i run it, I see no colors at all, as shown in this image. The color output of the ls command is working fine however.

enter image description here

nycynik
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6 Answers6

115

Use \033 or \x1B instead of \e to represent de <Esc> character.

echo -e "\033[1;31m This is red text \033[0m"

See http://misc.flogisoft.com/bash/tip_colors_and_formatting

guapolo
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54

OSX ships with an old version of Bash that does not support the \e escape character. Use \x1B or update Bash (brew install bash).

Even better, though, would be to use tput.

danemacmillan
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15

In script files printf could be yet another option, you have to add trailing "\n" though.

#!/bin/bash

echo -e "\e[31mOutput as is.\e[m"
printf "\e[32mThis is green line.\e[m\n"
printf "\e[33;1m%s\n" 'This is yellow bold line.'

Tested on macOS High Sierra 10.13.6:

% /bin/bash --version
GNU bash, version 3.2.57(1)-release (x86_64-apple-darwin17)
Copyright (C) 2007 Free Software Foundation, Inc.
cu39
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5

Another option could be using zsh, which respects the \e notation.

#!/bin/zsh
Adam Matan
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    Starting with macOS Catalina, Macs will now use zsh as the default login shell and interactive shell across the operating system. – nycynik Nov 27 '20 at 00:26
2

I wrote functions from @cu39 answer and used it like this:

#!/bin/bash

printy() {
  printf "\e[33;1m%s\n" "$1"
}
printg() {
  printf "\e[32m$1\e[m\n"
}
printr() {
  echo -e "\033[1;31m$1\033[0m"
}

printr "This is red"
printy "This is yellow"
printg "This is green"

The result:

enter image description here

MBH
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  • It's interesting that each function varies how it works - were you just showing how echo and printf can work? – nycynik Jul 29 '22 at 13:31
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    @nycynik Not showing anything, just putting it easy to copy and paste for who wants! – MBH Aug 03 '22 at 12:07
1

A quick exemple of how you can change text color. It's working with many different version of bash (Mac OS ready also tested on fedora 33 KDE and ubuntu jellyfish gnome).

In this exemple to show you how it work I use echo command with -e option to enable interpret backslash escapes and then use the this part \x1B[HX;Ym to start text modification.

H for  Highlight option
H = 3 --> Color text       H = 4 --> Highlight text

X for the color
X = 1 --> Red              X = 2 --> Green
X = 3 --> Yellow/orange    X = 4 --> Blue light
X = 5 --> Purple           X = 6 --> Blue dark

Y for the format
Y = 1 --> Bold             Y = 2 --> Normal
Y = 3 --> Italic           Y = 4 --> Underline

When you finish text modification use \x1B[0m

Try on your terminal :

echo -e "Hello my name is \x1B[34;2mVictor\x1B[0m I'm a \x1B[33;2msys-admin\x1B[0m \!\n"

https://github.com/victor-sys-admin/MODIFY_TEXT_OUTPUT_COLOR_BASH

Victor
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