curl 命令
查看网站源码
[root@localhost ~]# curl www.baidu.com
只查看网站状态信息
[root@localhost ~]# curl -I www.baidu.com
网站状态一般有：200，301，302，403，404，502，503
下图为状态200
下图为状态301，表示访问www.lishiming.net的时候会跳转到http://www.apelearn.com/bbs/forum.php
代理访问
[root@localhost ~]# ping baidu.com -c 3
PING baidu.com (220.181.57.217) 56(84) bytes of data.
64 bytes from 220.181.57.217: icmp_seq=1 ttl=53 time=37.1 ms
64 bytes from 220.181.57.217: icmp_seq=2 ttl=53 time=37.1 ms
64 bytes from 220.181.57.217: icmp_seq=3 ttl=53 time=37.3 ms
--- baidu.com ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2039ms
rtt min/avg/max/mdev = 37.128/37.225/37.359/0.243 ms
[root@localhost ~]# curl -x220.181.57.217:80 www.baidu.com -I
HTTP/1.1 200 OK
Date: Mon, 21 Dec 2015 09:08:47 GMT
Server: Apache
Cache-Control: max-age=86400
Expires: Tue, 22 Dec 2015 09:08:47 GMT
Last-Modified: Tue, 12 Jan 2010 13:48:00 GMT
ETag: "51-4b4c7d90"
Accept-Ranges: bytes
Content-Length: 81
Connection: Keep-Alive
Content-Type: text/html
显示访问过程
[root@localhost ~]# curl -Iv baidu.ocm
下载文件，大写O
[root@localhost ~]# curl -O https://www.baidu.com/img/bd_logo1.png
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 7877 100 7877 0 0 1365 0 0:00:05 0:00:05 --:--:-- 549k
下载文件并重命名，小写o
[root@localhost ~]# curl -o my.png https://www.baidu.com/img/bd_logo1.png
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 7877 100 7877 0 0 1538 0 0:00:05 0:00:05 --:--:-- 641k