linux shell 札记

shell 数组

数组索引:

单个元素索引: ${array[n]}

全部元素:   ${array[*]}  或者  ${array[@]} 

部分索引: ${array[2:]}

数组所有元素统一加前缀/后缀： 

array=( "${array[@]/%/_content}" )

array=( "${array[@]/#/prefix_}" ) 

流程控制 

for 语句

for var in $(ls ./home/data)
do
    sth
done
----------------------------------    
for ((i=0;i<cnt;i++));
do
    sth
done
----------------------------------
for loop in 1 2 3 4 5
do
    echo "The value is: $loop"
done