I got some point from others.I already red and debug network.c . Now I now
the basic logic behind that. But still I'm confused by arithmetic. I find
some comments on that , I need some one's help.
/*
* int
* bitncmp(l, r, n)
* compare bit masks l and r, for n bits.
* return:
* -1, 1, or 0 in the libc tradition.
* note:
* network byte order assumed. this means 192.5.5.240/28 has
* 0x11110000 in its fourth octet.
* author:
* Paul Vixie (ISC), June 1996
*/
Why we finish it in this way. Can you help me?