-int dgram_send(char *hostname, in_port_t port, dgram_t *dgram);
-int dgram_send_addr(struct sockaddr_in addr, dgram_t *dgram);
-ssize_t dgram_recv(dgram_t *dgram, int timeout, struct sockaddr_in *fromaddr);
+int dgram_send_addr(sockaddr_union *addr, dgram_t *dgram);
+ssize_t dgram_recv(dgram_t *dgram, int timeout,
+ sockaddr_union *fromaddr);