			arg1=arg;
			arg = rindex(arg,':');
			if (!arg) {
				fprintf(stderr,
					"Invalid host:port specification %s\n",
					host);
				continue;
			}
			*arg++='\0';
			port = atoi(arg1);
			if (port < 0) {
				fprintf(stderr, "Invalid port %s\n", arg);
				continue;
			}
			arg1=arg;
			arg = rindex(arg,':');
			if (!arg) {
				fprintf(stderr,
					"Invalid host:port specification %s\n",
					host);
				continue;
			}
			*arg++='\0';
			srcfd = arg1;
			destfd = arg;
