+#ifndef INET_ADDRSTRLEN
+#define INET_ADDRSTRLEN 16
+#endif
+
+#ifndef INET6_ADDRSTRLEN
+#define INET6_ADDRSTRLEN INET_ADDRSTRLEN
+#endif
+
+#ifndef IN_MULTICAST
+#define IN_MULTICAST(a) ((((uint32_t)(a)) & 0xf0000000) == 0xe0000000)
+#endif
+#ifndef IN6_IS_ADDR_MULTICAST
+#define IN6_IS_ADDR_MULTICAST(a) (((uint8_t *) (a))[0] == 0xff)
+#endif
+
+int ff_is_multicast_address(struct sockaddr *addr);
+
+#define POLLING_TIME 100 /// Time in milliseconds between interrupt check
+
+/**
+ * Bind to a file descriptor and poll for a connection.
+ *
+ * @param fd First argument of bind().
+ * @param addr Second argument of bind().
+ * @param addrlen Third argument of bind().
+ * @param timeout Polling timeout in milliseconds.
+ * @param h URLContext providing interrupt check
+ * callback and logging context.
+ * @return A non-blocking file descriptor on success
+ * or an AVERROR on failure.
+ */
+int ff_listen_bind(int fd, const struct sockaddr *addr,
+ socklen_t addrlen, int timeout,
+ URLContext *h);
+
+/**
+ * Connect to a file descriptor and poll for result.
+ *
+ * @param fd First argument of connect(),
+ * will be set as non-blocking.
+ * @param addr Second argument of connect().
+ * @param addrlen Third argument of connect().
+ * @param timeout Polling timeout in milliseconds.
+ * @param h URLContext providing interrupt check
+ * callback and logging context.
+ * @param will_try_next Whether the caller will try to connect to another
+ * address for the same host name, affecting the form of
+ * logged errors.
+ * @return 0 on success, AVERROR on failure.
+ */
+int ff_listen_connect(int fd, const struct sockaddr *addr,
+ socklen_t addrlen, int timeout,
+ URLContext *h, int will_try_next);
+
+int ff_http_match_no_proxy(const char *no_proxy, const char *hostname);
+
+int ff_socket(int domain, int type, int protocol);
+