inet_lnaof.c

来自「<B>Digital的Unix操作系统VAX 4.2源码</B>」· C语言 代码 · 共 23 行

/*	inet_lnaof.c	4.3	82/11/14	*/

#include <sys/types.h>
#include <netinet/in.h>

/*
 * Return the local network address portion of an
 * internet address; handles class a/b/c network
 * number formats.
 */
inet_lnaof(in)
	struct in_addr in;
{
	register u_long i = ntohl(in.s_addr);

	if (IN_CLASSA(i))
		return ((i)&IN_CLASSA_HOST);
	else if (IN_CLASSB(i))
		return ((i)&IN_CLASSB_HOST);
	else
		return ((i)&IN_CLASSC_HOST);
}