Colorful bash script [duplicate]

Question

I want to write a bash script that prints some information to the terminal STDOUT. For better readability and structure, I would like to color the different items and highlight them this way.

Now, is there a Bash equivalent to the Windows-CMD/DOS command COLOR which sets the currently used background and font color? And how do I reset the color back to the terminal default after finishing my script?

Edit:
I have read Pipable command to print in color?, but only some answers are written in Bash so that they can be easily included in my script. Besides this, the answers there lack the following points I want:

• change background color
• display white foreground color, the default color set in gnome-terminal gets displayed instead (which is neon green for me)
• make all available colors accessible somehow, not only a small subset by keywords. I could imagine e.g. some kind of RGB encoding to pass as function argument for easily specifying a color.

Answer 1

A small script to get the cryptic codes ;)

#!/bin/bash
#
#   This file echoes a bunch of color codes to the 
#   terminal to demonstrate what's available.  Each 
#   line is the color code of one forground color,
#   out of 17 (default + 16 escapes), followed by a 
#   test use of that color on all nine background 
#   colors (default + 8 escapes).
#

T='gYw'   # The test text

echo -e "\n                 40m     41m     42m     43m\
     44m     45m     46m     47m";

for FGs in '    m' '   1m' '  30m' '1;30m' '  31m' '1;31m' '  32m' \
           '1;32m' '  33m' '1;33m' '  34m' '1;34m' '  35m' '1;35m' \
           '  36m' '1;36m' '  37m' '1;37m';
  do FG=${FGs// /}
  echo -en " $FGs \033[$FG  $T  "
  for BG in 40m 41m 42m 43m 44m 45m 46m 47m;
    do echo -en "$EINS \033[$FG\033[$BG  $T  \033[0m";
  done
  echo;
done
echo

---

The code is easy to read from the table that generated the previous script.

\e[1;37m\e[44m

• \e[1;37m – Foreground

• \e[44m – Background

---

Some examples

• White foreground

  TOA="\e[0m" # No Color
  whiteForeground="\e[1;37m" 
  echo -e "${whiteForeground}foo${TOA}"
  

• White on blue

  TOA="\e[0m" # No Color
  whiteOnBlue="\e[1;37m\e[44m" 
  echo -e "${whiteOnBlue}foo${TOA}"
  

---

And a sample bash script:

red="\e[0;31m"
green="\e[0;32m"
yellow="\e[0;33m"
blue="\e[0;34m"
TOA="\e[0m" # No Color

if [[ $cfg_log_level == "" ]]; then
  cfg_log_level=4
fi

function logError () {
  if [[ $cfg_log_level == "1" ]] || [[ $cfg_log_level == "2" ]] || [[ $cfg_log_level == "3" ]] || [[ $cfg_log_level == "4" ]]; then
    echo -e "${red}$1${TOA}" 1>&2
  fi
}

function logWarn () {
  if [[ $cfg_log_level == "2" ]] || [[ $cfg_log_level == "3" ]] || [[ $cfg_log_level == "4" ]]; then
    echo -e "${yellow}$1${TOA}" 1>&2
  fi
}

function logInfo () {
  if [[ $cfg_log_level == "3" ]] || [[ $cfg_log_level == "4" ]]; then
    echo -e "${green}$1${TOA}" 1>&2
  fi
}

function logDebug () {
  if [[ $cfg_log_level == "4" ]]; then
    echo -e "${blue}$1${TOA}" 1>&2
  fi
}

Answer 2

You could use tput

• tput setaf <color> sets the foreground color
• tput setab <color> sets the background color

the colors are 1 bit b,g,r:

  0. black
  1. red
  2. green
  3. yellow
  4. blue
  5. magenta
  6. cyan
  7. white

tput can set other attributes of the characters such as underline, bold, blink etc. see man terminfo for more information.

I think that a good way of using this is by setting variables shemantically. i.e.

startheader=`tput setaf 0``tput setab 7`
endheader=`tput sgr0`
startprompt=`tput bold`
endprompt=$endheader

echo ${startheader}The Header${endheader}
echo -n ${startprompt}Enter value: ${endprompt}
read value