if (! host_lookup) { return strdup("unknown"); }
char *ip2host(char *ip) {	char *str;#if LIBVNCSERVER_HAVE_NETDB_H && LIBVNCSERVER_HAVE_NETINET_IN_H	struct hostent *hp;	in_addr_t iaddr;	iaddr = inet_addr(ip);	if (iaddr == htonl(INADDR_NONE)) {		return strdup("unknown");	}	hp = gethostbyaddr((char *)&iaddr, sizeof(in_addr_t), AF_INET);	if (!hp) {		return strdup("unknown");	}	str = strdup(hp->h_name);#else	str = strdup("unknown");#endif	return str;}