rem: interfaces()
add: interfaces(void)
context: interfaces(){	size_t needed;	int mib[6];	char *buf = NULL, *lim, *next;	struct rt_msghdr *rtm;	mib[0] = PF_ROUTE;	mib[1] = 0;		/* protocol */	mib[2] = 0;		/* wildcard address family */	mib[3] = NET_RT_IFLIST;	mib[4] = 0;		/* no flags */	if (sysctl(mib, 5, NULL, &needed, NULL, 0) < 0)		quit("route-sysctl-estimate");	if (needed) {		if ((buf = malloc(needed)) == NULL)			quit("malloc");		if (sysctl(mib, 5, buf, &needed, NULL, 0) < 0)			quit("actual retrieval of interface table");		lim = buf + needed;		for (next = buf; next < lim; next += rtm->rtm_msglen) {			rtm = (struct rt_msghdr *)next;			print_rtmsg(rtm, rtm->rtm_msglen);		}		free(buf);	}}