第4天.Linux C的暂停

太底层了，操作系统之后再来。。。。

http://www.tuicool.com/articles/2iYvum

http://xidianzhangjun.blog.163.com/blog/static/115488771201072081052719/

http://m.blog.csdn.net/blog/DLUTBruceZhang/8665547  

http://bbs.csdn.net/topics/230035323

http://blog.chinaunix.net/uid-20672257-id-1901040.html

http://blog.sina.com.cn/s/blog_574f9aa00100rofk.html

http://blog.163.com/njut_wangjian/blog/static/165796425201242981639128/

http://blog.csdn.net/yahohi/article/details/6718275