mmap

http://www.cnblogs.com/noaming1900/archive/2010/10/20/1856797.html

http://blog.csdn.net/joejames/article/details/37958017

http://www.it165.net/os/html/201503/11918.html

http://blog.csdn.net/leoleocmm/article/details/8671035

http://blog.chinaunix.net/uid-20321537-id-3483405.html

http://blog.csdn.net/vc0051127833/article/details/7568932