+ * @param success #GNUNET_OK or #GNUNET_SYSERR
+ */
+typedef void
+(*GNUNET_PEERSTORE_Continuation)(void *cls,
+ int success);
+
+
+/**
+ * Function called by PEERSTORE for each matching record.
+ *
+ * @param cls closure
+ * @param record peerstore record information
+ * @param emsg error message, or NULL if no errors
+ */
+typedef void
+(*GNUNET_PEERSTORE_Processor) (void *cls,
+ const struct GNUNET_PEERSTORE_Record *record,
+ const char *emsg);
+
+
+/**
+ * Connect to the PEERSTORE service.
+ *
+ * @return NULL on error
+ */
+struct GNUNET_PEERSTORE_Handle *
+GNUNET_PEERSTORE_connect (const struct GNUNET_CONFIGURATION_Handle *cfg);
+
+
+/**
+ * Disconnect from the PEERSTORE service. Any pending ITERATE and WATCH requests
+ * will be canceled.
+ * Any pending STORE requests will depend on @e snyc_first flag.
+ *
+ * @param h handle to disconnect
+ * @param sync_first send any pending STORE requests before disconnecting
+ */
+void
+GNUNET_PEERSTORE_disconnect (struct GNUNET_PEERSTORE_Handle *h,
+ int sync_first);
+
+
+/**
+ * Store a new entry in the PEERSTORE.
+ * Note that stored entries can be lost in some cases
+ * such as power failure.
+ *
+ * @param h Handle to the PEERSTORE service
+ * @param sub_system name of the sub system
+ * @param peer Peer Identity
+ * @param key entry key
+ * @param value entry value BLOB
+ * @param size size of @e value
+ * @param expiry absolute time after which the entry is (possibly) deleted
+ * @param options options specific to the storage operation
+ * @param cont Continuation function after the store request is sent
+ * @param cont_cls Closure for @a cont
+ */
+struct GNUNET_PEERSTORE_StoreContext *
+GNUNET_PEERSTORE_store (struct GNUNET_PEERSTORE_Handle *h,
+ const char *sub_system,
+ const struct GNUNET_PeerIdentity *peer,
+ const char *key,
+ const void *value,
+ size_t size,
+ struct GNUNET_TIME_Absolute expiry,
+ enum GNUNET_PEERSTORE_StoreOption options,
+ GNUNET_PEERSTORE_Continuation cont,
+ void *cont_cls);
+
+
+/**
+ * Cancel a store request
+ *
+ * @param sc Store request context
+ */
+void
+GNUNET_PEERSTORE_store_cancel (struct GNUNET_PEERSTORE_StoreContext *sc);
+
+
+/**
+ * Iterate over records matching supplied key information
+ *
+ * @param h handle to the PEERSTORE service
+ * @param sub_system name of sub system
+ * @param peer Peer identity (can be NULL)
+ * @param key entry key string (can be NULL)
+ * @param timeout time after which the iterate request is canceled
+ * @param callback function called with each matching record, all NULL's on end
+ * @param callback_cls closure for @a callback
+ */
+struct GNUNET_PEERSTORE_IterateContext *
+GNUNET_PEERSTORE_iterate (struct GNUNET_PEERSTORE_Handle *h,
+ const char *sub_system,
+ const struct GNUNET_PeerIdentity *peer,
+ const char *key,
+ struct GNUNET_TIME_Relative timeout,
+ GNUNET_PEERSTORE_Processor callback,
+ void *callback_cls);
+
+
+/**
+ * Cancel an iterate request
+ * Please do not call after the iterate request is done
+ *
+ * @param ic Iterate request context as returned by GNUNET_PEERSTORE_iterate()
+ */
+void
+GNUNET_PEERSTORE_iterate_cancel (struct GNUNET_PEERSTORE_IterateContext *ic);
+
+
+/**
+ * Request watching a given key
+ * User will be notified with any new values added to key.
+ *
+ * @param h handle to the PEERSTORE service
+ * @param sub_system name of sub system
+ * @param peer Peer identity
+ * @param key entry key string
+ * @param callback function called with each new value
+ * @param callback_cls closure for @a callback
+ * @return Handle to watch request