4，linux 命令 awk1

[root@node1 ~]# cat t2.awk

#! /bin/awk

BEGIN{

 array[1]="a"

 array[2]="b"

 for( i in array)

    print i array[i]

}

[root@node1 ~]#

[root@node1 ~]#

[root@node1 ~]#

[root@node1 ~]#

[root@node1 ~]#

[root@node1 ~]# awk -f t2.awk

1a

2b

[root@node1 ~]#

[root@node1 ~]# cat a.txt

http://www.etiantian.org/index.html

http://www.etiantian.org/1.html

http://post.etiantian.org/index.html

http://mp3.etiantian.org/index.html

http://www.etiantian.org/3.html

http://post.etiantian.org/2.html

[root@node1 ~]# awk -F "/" '{print $3}' a.txt

www.etiantian.org

www.etiantian.org

post.etiantian.org

mp3.etiantian.org

www.etiantian.org

post.etiantian.org

[root@node1 ~]# awk -F "/" '{S[$3]=S[$3]+1}END{for(k in S) print  k,S[k]}' a.txt

mp3.etiantian.org 1

www.etiantian.org 3

post.etiantian.org 2

[root@node1 ~]# awk -F "/" '{S[$3]++}END{for(k in S) print  k,S[k]}' a.txt

mp3.etiantian.org 1

www.etiantian.org 3

post.etiantian.org 2

[root@node1 ~]#