Shell 帶顏色輸出

#!/bin/bash

# Color
RESTORE=$(echo -en '\033[0m')
RED=$(echo -en '\033[00;31m')
GREEN=$(echo -en '\033[00;32m')
YELLOW=$(echo -en '\033[00;33m')
BLUE=$(echo -en '\033[00;34m')
MAGENTA=$(echo -en '\033[00;35m')
PURPLE=$(echo -en '\033[00;35m')
CYAN=$(echo -en '\033[00;36m')
LIGHTGRAY=$(echo -en '\033[00;37m')
LRED=$(echo -en '\033[01;31m')
LGREEN=$(echo -en '\033[01;32m')
LYELLOW=$(echo -en '\033[01;33m')
LBLUE=$(echo -en '\033[01;34m')
LMAGENTA=$(echo -en '\033[01;35m')
LPURPLE=$(echo -en '\033[01;35m')
LCYAN=$(echo -en '\033[01;36m')
WHITE=$(echo -en '\033[01;37m')
RESTORE=$(echo -en '\033[0m')

echo_color() {
case $1 in
    red)
        echo "${RED} $2  ${RESTORE}" 
    ;;
    green)
        echo "${GREEN} $2  ${RESTORE}"
    ;;
    yellow)
        echo "${YELLOW} $2  ${RESTORE}"
    ;;
    blue)
         echo "${BLUE} $2  ${RESTORE}"
    ;;
    *)
		echo "`basename ${0}`:usage: color content"	        
        echo "only red,green,yellow,blue was set!"
esac
}

# check $1 exist
# 以下 4 個方式都可以
# if test -z $1
# if [ ! $1 ] 
# if [ ! -n "$1" ]
if [ "$1" = "" ]
then
        echo "`basename ${0}`:usage: color content"
        exit 1
# else
		echo_color $1 $2
fi

附上一個 shell 學習網站

Shell腳本：Linux Shell腳本學習指南（超詳細）
http://c.biancheng.net/shell/

附上幾條查詢 shell 的指令

1. 查詢當前使用的 shell
   $ bash --version

    GNU bash, version 4.4.20(1)-release (x86_64-pc-linux-gnu)
    Copyright (C) 2016 Free Software Foundation, Inc.
    License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
    
    This is free software; you are free to change and redistribute it.
    There is NO WARRANTY, to the extent permitted by law.
   

   ps -p $$

    PID TTY          TIME CMD
    3989 pts/0    00:00:00 bash
   

   echo $0

    /bin/bash
   

   echo $SHELL

    /bin/bash
   

2. 查詢系統支持的 shell
   $ ls /bin/*sh

    /bin/bash  /bin/dash  /bin/rbash  /bin/sh  /bin/static-sh
   

   $ cat /etc/shells

    # /etc/shells: valid login shells
    /bin/sh
    /bin/bash
    /bin/rbash
    /bin/dash
    /usr/bin/tmux
    /usr/bin/screen