Ubuntu – Changing colour of text and background of terminal

On certain XTerm/ANSI-compatible terminals (like xterm and gnome-terminal), you can set colors using a palette bigger then the default 8/16-colors palette (for example using an 88-colors, 256-colors or 16777216-colors (RGB) palette; both xterm and gnome-terminal support both the 256-colors and the 16777216-colors (RGB) palette); mind that the shell might override this (this is the case e.g. for zsh).

Here's a script to list the colors in the 256-color palette along with their ANSI color code in XTerm/ANSI-compatible terminals with a 256-color palette support:

#!/bin/bash
for((i=16; i<256; i++)); do
    printf "\e[48;5;${i}m%03d" $i;
    printf '\e[0m';
    [ ! $((($i - 15) % 6)) -eq 0 ] && printf ' ' || printf '\n'
done

Depending on whether you want to apply the color to the foreground or to the background, use an <fg_bg> value of 38 or 48 (respectively) in the following command:

printf '\e[<fg_bg>;5;<ANSI_color_code>m'

For example, to set the foreground color (<fg_bg>=38) to red (<ANSI_color_code>=196) and the background color (<fg_bg>=48) to black (<ANSI_color_code>=0):

printf '\e[38;5;196m Foreground color: red\n'
printf '\e[48;5;0m Background color: black\n'

It's necessary to redraw the prompt using printf '\e[K' in order for the background color to apply to the whole line and in order for the foreground color to apply to the cursor:

The same thing can be accomplished using RGB values instead of ANSI color codes in a compatible terminal; depending on whether you want to apply the color to the foreground or to the background, use an <fg_bg> value of 38 or 48 (respectively) in the following command:

printf '\e[<fg_bg>;2;<R>;<G>;<B>m'

For example, to set the foreground color (<fg_bg>=38) to red (<R>=255, <G>=0, <B>=0) and the background color (<fg_bg>=48) to black (<R>=0, <G>=0, <B>=0):

printf '\e[38;2;255;0;0m Foreground color: red\n'
printf '\e[48;2;0;0;0m Background color: black\n'

Again, it's necessary to redraw the prompt using printf '\e[K' in order for the background color to apply to the whole line and in order for the foreground color to apply to the cursor:

Using either methods, you can use printf '\e[0m' to reset all the attributes: