+ * UNIX socket address being returned, IPX sockaddr etc...
+ * On error does bb_error_msg and returns NULL */
+len_and_sockaddr* host2sockaddr(const char *host, int port);
+/* Version which dies on error */
+len_and_sockaddr* xhost2sockaddr(const char *host, int port);
+len_and_sockaddr* xdotted2sockaddr(const char *host, int port);
+#if ENABLE_FEATURE_IPV6
+/* Same, useful if you want to force family (e.g. IPv6) */
+len_and_sockaddr* host_and_af2sockaddr(const char *host, int port, sa_family_t af);
+len_and_sockaddr* xhost_and_af2sockaddr(const char *host, int port, sa_family_t af);
+#else
+/* [we evaluate af: think about "host_and_af2sockaddr(..., af++)"] */
+#define host_and_af2sockaddr(host, port, af) ((void)(af), host2sockaddr((host), (port)))
+#define xhost_and_af2sockaddr(host, port, af) ((void)(af), xhost2sockaddr((host), (port)))
+#endif
+/* Assign sin[6]_port member if the socket is of corresponding type,
+ * otherwise no-op. Useful for ftp.
+ * NB: does NOT do htons() internally, just direct assignment. */
+void set_nport(len_and_sockaddr *lsa, unsigned port);
+/* Retrieve sin[6]_port or return -1 for non-INET[6] lsa's */
+int get_nport(const len_and_sockaddr *lsa);
+/* Reverse DNS. Returns NULL on failure. */
+char* xmalloc_sockaddr2host(const struct sockaddr *sa, socklen_t salen);
+/* This one doesn't append :PORTNUM */
+char* xmalloc_sockaddr2host_noport(const struct sockaddr *sa, socklen_t salen);
+/* This one also doesn't fall back to dotted IP (returns NULL) */
+char* xmalloc_sockaddr2hostonly_noport(const struct sockaddr *sa, socklen_t salen);
+/* inet_[ap]ton on steroids */
+char* xmalloc_sockaddr2dotted(const struct sockaddr *sa, socklen_t salen);
+char* xmalloc_sockaddr2dotted_noport(const struct sockaddr *sa, socklen_t salen);
+// "old" (ipv4 only) API
+// users: traceroute.c hostname.c
+struct hostent *xgethostbyname(const char *name);
+// Also inetd.c and inetd.c are using gethostbyname(),
+// + inet_common.c has additional IPv4-only stuff