/***************************** 目录 *************************/
1,流程控制
/*************************** 1流程控制 ******************/
(1) case
case ${1} in
"hello")
echo "Hello, how are you ?"
;;
"")
echo "You MUST input parameters, ex> {${0} someword}"
;;
*) #其实就相当于万用字元，0~无穷多个任意字元之意！
echo "Usage ${0} {hello}"
;;
esac