fprintf(f, "\n");
add_host_to_hostfile(const char *filename, const char *host, Key *key){	FILE *f;	int success = 0;	if (key == NULL)		return 1;	/* Open the file for appending. */	f = fopen(filename, "a");	if (!f)		return 0;	fprintf(f, "%s ", host);	if (key_write(key, f)) {		fprintf(f, "\n");		success = 1;	} else {		error("add_host_to_hostfile: saving key failed");	}	/* Close the file. */	fclose(f);	return success;}