Shell script: 循环

语法：

for name [ in [word ... ]]
do
    compound-list
done

例如：

#!/bin/bash
for i in {1..3}
do
   echo "Welcome $i times"
done

运行结果：

Welcome 1 times
Welcome 2 times
Welcome 3 times

另外一种写法，看上去与Ｃ语言类似：

#!/bin/bash
for ((i = 1; i <= 3; i++));
do
   echo "Welcome $i times"
done

运行结果和上面是一样的。

还有一种方法，直接在shell命令行中运行：

$ for i in {1..3}; do echo "Welcome $i times"; done
Welcome 1 times
Welcome 2 times
Welcome 3 times

参考
http://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html