linux系統中如何刪除第一行、前兩行，最后一行、最后兩行

 

1、測試數據如下：

[root@PC3 test]# cat a.txt 1 Beijing 2003
2 Beijing 2004
3 Beijing 2005
4 Beijing 2006
5 Beijing 2007
6 Beijing 2008
7 Beijing 2007
8 Beijing 2005
9 Beijing 2006
10 Beijing 2007
11 Beijing 2008
12 Beijing 2007

 

2、刪除第一行

[root@PC3 test]# sed 1d a.txt 2 Beijing 2004
3 Beijing 2005
4 Beijing 2006
5 Beijing 2007
6 Beijing 2008
7 Beijing 2007
8 Beijing 2005
9 Beijing 2006
10 Beijing 2007
11 Beijing 2008
12 Beijing 2007

 

[root@PC3 test]# tail -n +2 a.txt 2 Beijing 2004
3 Beijing 2005
4 Beijing 2006
5 Beijing 2007
6 Beijing 2008
7 Beijing 2007
8 Beijing 2005
9 Beijing 2006
10 Beijing 2007
11 Beijing 2008
12 Beijing 2007

 

3、刪除前兩行

[root@PC3 test]# sed 1,2d a.txt 3 Beijing 2005
4 Beijing 2006
5 Beijing 2007
6 Beijing 2008
7 Beijing 2007
8 Beijing 2005
9 Beijing 2006
10 Beijing 2007
11 Beijing 2008
12 Beijing 2007

 

[root@PC3 test]# tail -n +3 a.txt 3 Beijing 2005
4 Beijing 2006
5 Beijing 2007
6 Beijing 2008
7 Beijing 2007
8 Beijing 2005
9 Beijing 2006
10 Beijing 2007
11 Beijing 2008
12 Beijing 2007

 

4、刪除最后一行

[root@PC3 test]# sed '$d' a.txt 1 Beijing 2003
2 Beijing 2004
3 Beijing 2005
4 Beijing 2006
5 Beijing 2007
6 Beijing 2008
7 Beijing 2007
8 Beijing 2005
9 Beijing 2006
10 Beijing 2007
11 Beijing 2008

 

[root@PC3 test]# head -n -1 a.txt 1 Beijing 2003
2 Beijing 2004
3 Beijing 2005
4 Beijing 2006
5 Beijing 2007
6 Beijing 2008
7 Beijing 2007
8 Beijing 2005
9 Beijing 2006
10 Beijing 2007
11 Beijing 2008

 

5、刪除最后兩行

[root@PC3 test]# head -n -2 a.txt 1 Beijing 2003
2 Beijing 2004
3 Beijing 2005
4 Beijing 2006
5 Beijing 2007
6 Beijing 2008
7 Beijing 2007
8 Beijing 2005
9 Beijing 2006
10 Beijing 2007