【shell】shell if else 语句的语法和使用

Shell if else语句

https://www.orchome.com/418

shell的if和else

https://www.cnblogs.com/matthewma/p/6995479.html

Shell if else语句

http://c.biancheng.net/view/1262.html

Linux Shell中if多重条件的写法

https://shipengliang.com/program-code/linux-shell%E4%B8%ADif%E5%A4%9A%E9%87%8D%E6%9D%A1%E4%BB%B6%E7%9A%84%E5%86%99%E6%B3%95.html