20150826

行缓冲介绍：
/> 共享内存和文件映射
http://blog.sina.com.cn/s/blog_61e531350100pb4n.html
信号：
/> http://www.cnblogs.com/hoys/archive/2012/08/19/2646377.html
%28SIGALRM%2C+sighand%29%3B+ctrl+%2B+c&ie=utf-8&ssl_sample=hao_1
http://blog.csdn.net/cjsycyl/article/details/22667023
http://blog.sina.com.cn/s/blog_6a1837e90100v1vc.html
%28SIGALRM%2C+sighand%29%3B+usleep&ie=utf-8&ssl_sample=hao_1
/> /> http://blog.csdn.net/tiany524/article/details/17048069
http://blog.sina.com.cn/s/blog_8184e03301013ddz.html
/> %28MCL_CURRENT+%7C+MCL_FUTURE%29%3B&ie=utf-8&ssl_sample=hao_1#ie=utf-8&f=8&rsv_bp=1&wd=signal(SIGALRM%2C%20sighand)%3B&oq=STDsysconf(_SC_NPROCESSORS_ONLN)%3B&rsv_pq=c27fb0e500007da9&rsv_t=62909BcyllzbdWkVmZjy3huYQ6Bu7dhB1pQaeV9EG%2BDuDl4zexonxc82JT1EHDv%2FuLhABfS9UFY5&rsv_enter=0&inputT=1886&rsv_n=2&rsv_sug3=15&rsv_sug4=1887&rsv_sug=1

进程调用线程