[root@localhost ~]# nl file.txt | sed "1a add text"
1 wtmp begins Mon Feb 24 14:26:08 2014
add text
2 192.168.0.1
3 162.12.0.123
4 this is the last line(2)第一行之前添加一行[root@localhost ~]# nl file.txt | sed "1i add text"
add text
1 wtmp begins Mon Feb 24 14:26:08 2014
2 192.168.0.1
3 162.12.0.123
4 this is the last line（3）删除第2,3行[root@localhost ~]# nl file.txt | sed "2,3d"
1 wtmp begins Mon Feb 24 14:26:08 2014
4 this is the last line（4）打印第2,3行[root@localhost ~]# sed -n "2,3p" file.txt 192.168.0.1 162.12.0.123
[root@localhost ~]# sed "2,3p" file.txt wtmp begins Mon Feb 24 14:26:08 2014 192.168.0.1 192.168.0.1 162.12.0.123 162.12.0.123 this is the last line
[root@localhost ~]# cat file.txt wtmp begins Mon Feb 24 14:26:08 2014 192.168.0.1 162.12.0.123 this is the last line处理后
[root@localhost ~]# sed "s/168/169/g" file.txt wtmp begins Mon Feb 24 14:26:08 2014 192.169.0.1 162.12.0.123 this is the last line
[root@localhost ~]# nl file.txt | sed "2afirst\nsecond" file.txt wtmp begins Mon Feb 24 14:26:08 2014 192.168.0.1 first second 162.12.0.123 this is the last line
[root@localhost ~]# nl file.txt | sed "/begin/d"
2 192.168.0.1
3 162.12.0.123
4 this is the last line匹配123,并且把含有123的行162都替换成172[root@localhost ~]# nl file.txt | sed "/123/{s/162/172/g;q}"
1 wtmp begins Mon Feb 24 14:26:08 2014
2 192.168.0.1
3 172.12.0.123
4 this is the last line这里大括号{}里可以执行多个命令，用;隔开即可,q是退出<pre name="code" class="plain">[root@localhost ~]# nl file.txt | sed -e "2d" -e "s/last/new/"
1 wtmp begins Mon Feb 24 14:26:08 2014
3 162.12.0.123
4 this is the new line
[root@localhost ~]# sed -i "/begin/{s/24/25/g}" file.txt
[root@localhost ~]# cat file.txt
wtmp begins Mon Feb 25 14:26:08 2014
192.168.0.1
162.12.0.123
this is the last line[root@localhost ~]# sed ':a;N;$!ba;s/\n/ /g' file.txt wtmp begins Mon Feb 25 14:26:08 2014 192.168.0.1 162.12.0.123 this is the last line
第二种方式
[root@localhost ~]# tr "\n" " " < file.txt wtmp begins Mon Feb 25 14:26:08 2014 192.168.0.1 162.12.0.123 this is the last line last linen
Linux Sed命令详解+如何替换换行符"\n"(很多面试问道)
原文地址：http://blog.csdn.net/hello_hwc/article/details/40118129
