http://blog.sina.com.cn/s/blog_7e0127220100zfbf.html
http://blog.csdn.net/doubleuto/article/details/8859687
http://blog.chinaunix.net/uid-2270658-id-247815.html
http://blog.csdn.net/foxman209/article/details/6278093
http://www.cnblogs.com/gbyukg/p/3326825.html
http://man.linuxde.net/curl
https://www.baidu.com/s?ie=utf-8&f=8&rsv_bp=1&ch=&tn=56060048_4_pg&bar=&wd=curl_easy_setopt&oq=curl_setopt&rsv_pq=eb3faf7e0044c431&rsv_t=38fe3QrSHxjKm9duZiy9FhV3wwJYttsJvmdK%2FQ0TIALrjLQesBrmH2bbvAUk4n0IsBSHQQ&rqlang=cn&rsv_enter=1&inputT=6031