All such functions return a newly allocated cache or NULL
in case of an error.
+=== Cache Manager
+
+The purpose of a cache manager is to keep track of caches and
+automatically receive event notifications to keep the caches
+up to date with the kernel state. Each manager has exactly one
+netlink socket assigned which limits the scope of each manager
+to exactly one netlink family. Therefore all caches committed
+to a manager must be part of the same netlink family. Due to the
+nature of a manager, it is not possible to have a cache maintain
+two instances of the same cache type. The socket is subscribed
+to the event notification group of each cache and also put into
+non-blocking mode. Functions exist to poll() on the socket to
+wait for new events to be received.
+
+
+----
+ App libnl Kernel
+ | |
+ +-----------------+ [ notification, link change ]
+ | | Cache Manager | | [ (IFF_UP | IFF_RUNNING) ]
+ | | |
+ | | +------------+| | | [ notification, new addr ]
+ <-------|---| route/link |<-------(async)--+ [ 10.0.1.1/32 dev eth1 ]
+ | | +------------+| | |
+ | +------------+| |
+ <---|---|---| route/addr |<------|-(async)--------------+
+ | +------------+|
+ | | +------------+| |
+ <-------|---| ... ||
+ | | +------------+| |
+ +-----------------+
+ | |
+----
+
+.Creating a new cache manager
+
+[source,c]
+----
+struct nl_cache_mngr *mngr;
+
+// Allocate a new cache manager for RTNETLINK and automatically
+// provide the caches added to the manager.
+mngr = nl_cache_mngr_alloc(NETLINK_ROUTE, NL_AUTO_PROVIDE);
+----
+
+.Keep track of a cache
+
+[source,c]
+----
+struct nl_cache *cache;
+
+// Create a new cache for links/interfaces and ask the manager to
+// keep it up to date for us. This will trigger a full dump request
+// to initially fill the cache.
+cache = nl_cache_mngr_add(mngr, "route/link");
+-----
+
+.Make the manager receive updates
+
+[source,c]
+----
+// Give the manager the ability to receive updates, will call poll()
+// with a timeout of 5 seconds.
+if (nl_cache_mngr_poll(mngr, 5000) > 0) {
+ // Manager received at least one update, dump cache?
+ nl_cache_dump(cache, ...);
+}
+----
+
+.Release cache manager
+
+[source,c]
+----
+nl_cache_mngr_free(mngr);
+----
+
== Abstract Data Types
A few high level abstract data types which are used by a majority netlink
/**
* @ingroup cache_mngt
* @defgroup cache_mngr Manager
- * @brief Helps keeping caches up to date.
+ * @brief Automatically keep caches up to date
*
- * The purpose of a cache manager is to keep track of caches and
- * automatically receive event notifications to keep the caches
- * up to date with the kernel state. Each manager has exactly one
- * netlink socket assigned which limits the scope of each manager
- * to exactly one netlink family. Therefore all caches committed
- * to a manager must be part of the same netlink family. Due to the
- * nature of a manager, it is not possible to have a cache maintain
- * two instances of the same cache type. The socket is subscribed
- * to the event notification group of each cache and also put into
- * non-blocking mode. Functions exist to poll() on the socket to
- * wait for new events to be received.
- *
- * @code
- * App libnl Kernel
- * | |
- * +-----------------+ [ notification, link change ]
- * | | Cache Manager | | [ (IFF_UP | IFF_RUNNING) ]
- * | | |
- * | | +------------+| | | [ notification, new addr ]
- * <-------|---| route/link |<-------(async)--+ [ 10.0.1.1/32 dev eth1 ]
- * | | +------------+| | |
- * | +------------+| |
- * <---|---|---| route/addr |<------|-(async)--------------+
- * | +------------+|
- * | | +------------+| |
- * <-------|---| ... ||
- * | | +------------+| |
- * +-----------------+
- * | |
- * @endcode
- *
- * @par 1) Creating a new cache manager
- * @code
- * struct nl_cache_mngr *mngr;
- *
- * // Allocate a new cache manager for RTNETLINK and automatically
- * // provide the caches added to the manager.
- * mngr = nl_cache_mngr_alloc(NETLINK_ROUTE, NL_AUTO_PROVIDE);
- * @endcode
- *
- * @par 2) Keep track of a cache
- * @code
- * struct nl_cache *cache;
- *
- * // Create a new cache for links/interfaces and ask the manager to
- * // keep it up to date for us. This will trigger a full dump request
- * // to initially fill the cache.
- * cache = nl_cache_mngr_add(mngr, "route/link");
- * @endcode
- *
- * @par 3) Make the manager receive updates
- * @code
- * // Give the manager the ability to receive updates, will call poll()
- * // with a timeout of 5 seconds.
- * if (nl_cache_mngr_poll(mngr, 5000) > 0) {
- * // Manager received at least one update, dump cache?
- * nl_cache_dump(cache, ...);
- * }
- * @endcode
- *
- * @par 4) Release cache manager
- * @code
- * nl_cache_mngr_free(mngr);
- * @endcode
* @{
*/