在Linux上，如果您使用的是响应SGR标准的滚动终端，则发送到该显示流的颜色指令将保留（持续），直到您使用“clear”命令刷新该显示流。
以下脚本的执行将说明使用一组FG/BG颜色，然后使用终端默认值，然后使用另一组FG/BG颜色：

#!/bin/sh

### Useful References:
###     https://www.ecma-international.org/publications-and-standards/standards/ecma-48/
###     https://en.wikipedia.org/wiki/ANSI_escape_code
###
###     https://www.htmlcsscolor.com/hex/FFFF80
###     https://www.w3schools.com/colors/colors_picker.asp?colorhex=FFFF00
###     https://www.colorabout.com/color/hex/ffff80/
###     https://www.color-name.com/hex/ffff80
###     https://www.cpcwiki.eu/index.php/CPC_Palette
###     https://hexcolor.co/hex/ffff80
###     https://www.colorxs.com/color/hex-ffff80
###     https://encycolorpedia.com/ffff80
###     https://www.color-hex.com/color/ffff80
###     https://www.colorcodehex.com/ffff80.html
###     http://html-color.org/FFFF80

cat >sample_text.txt <<"EnDoFiNpUt"
The original specification only had 8 colors, and just gave them names. The SGR parameters 30–37 selected the foreground color, while 40–47 selected the background. Quite a few terminals implemented "bold" (SGR code 1) as a brighter color rather than a different font, thus providing 8 additional foreground colors. Usually you could not get these as background colors, though sometimes inverse video (SGR code 7) would allow that.
EnDoFiNpUt

    FG_color="\e[91m"       ### Red
    BG_color="\e[47m"       ### Gray
    echo "${FG_color}${BG_color}" 
    cat sample_text.txt 

    echo "\e[0m"            ### Environment Default
    cat sample_text.txt 

    FG_color="\e[30m"       ### Black
    BG_color="\e[102m"      ### Green
    echo "${FG_color}${BG_color}" 
    cat sample_text.txt 
    echo "\e[0m"

将显示如下（在我的终端上）：