shell中处理循环和字符串分割2种方法

方法1：(推荐)

luther=$1
[ "$luther" ] || luther=1,2,3,4,5,6,7
luther=${luther//,/ }
for element in $luther; do
    echo $element
done

方法2：(不推荐)

luther=${1}
[ "$luther" ] || luther=1,2,3,4,5,6,7

index=1
while [ 1 ]; do
element=$(echo ${luther} | awk -F',' '{print $"'$index'"}')
[ "${element}" ] || exit 0;
echo $element
((index++))
done