awk取列数；sed取行数。格式如下
[root@Charlie test]# ls
a.txt b.txt c.txt d.txt e.txt f.txt g.txt h.txt i.txt
[root@Charlie test]# ll -l
total 0
-rw-r--r-- 1 root root 0 Nov 15 04:58 a.txt
-rw-r--r-- 1 root root 0 Nov 15 04:58 b.txt
-rw-r--r-- 1 root root 0 Nov 15 04:58 c.txt
-rw-r--r-- 1 root root 0 Nov 15 04:58 d.txt
-rw-r--r-- 1 root root 0 Nov 15 04:58 e.txt
-rw-r--r-- 1 root root 0 Nov 15 04:58 f.txt
-rw-r--r-- 1 root root 0 Nov 15 04:58 g.txt
-rw-r--r-- 1 root root 0 Nov 15 04:58 h.txt
-rw-r--r-- 1 root root 0 Nov 15 04:58 i.txt
[root@Charlie test]# ll -l|awk '{print $9}'|sed -n '4p'
c.txt
