步进循环语句for

一、for语句的基本格式

for 变量 in 列表
do
    语句块
done

二、使用for语句处理列表（数组）

[root@localhost shell]# cat use_for_deal_with_list.sh
#!/bin/bash

#Use for loop deal with list.
#2013.12.20

I=1
for LOOP in 1 2 3 4 5 6
 do
        echo "loop:"$I
        echo "LOOP="$LOOP
        I=`expr $I + 1`
done
exit 0

[root@localhost shell]# cat use_for_deal_with_array.sh
#!/bin/bash

#Use for loop deal with array.
#2013.12.20

I=1
ARR=(1 2 3 4 5 6)
for LOOP in ${ARR[*]}
 do
        echo "loop:"$I
        echo "LOOP="$LOOP
        I=`expr $I + 1`
done
exit 0