extern size_t rstrip(char *value);
extern char *get_my_name(bool verbose) ATTR_MALLOC;
extern bool connect_tincd(bool verbose);
-extern bool sendline(int fd, const char *format, ...);
+extern bool sendline(int fd, const char *format, ...) ATTR_FORMAT(printf, 2, 3);
extern bool recvline(int fd, char *line, size_t len);
extern int check_port(const char *name);