Shell script recursively prints all catalog files in the specified directory

#!/bin/bash
#递归打印当前目录下的所有目录文件.  
PRINTF ()
{
ls $ | While read line
#一次读取每一行放到line变量中
do
  [-D $1/$line] && {
         dir= "$1/$line"
         echo $ DIR
      }
     dir1= ' dirname $DIR '
#求路径.
     a= ' ls-f $DIR 1 | grep/| grep "\< $line \>"
     #判断line是不是一个目录.
     if ["$A" = "$line/"];then
         PRINTF "$DIR 1/$line" #递归调用.
       fi
Done
}
PRINTF.


#!/bin/bash
#这个的实现递归总是无法递归到第一层. 
PRINTF ()
{
  ls  | While read line
  do
  pwd
#测试当前路径.
  [-D./$line] &&{
        echo $line
        CD./$line 
    #这里有问题, has not yet recursion has entered the next level,
    #所以就出现了我上面的解法.
        PRINTF 
        }
    Done
}
PRINTF