- stream_set_write_buffer() no longer changes the chunk size in socket streams.
- fclose() closes streams with resource refcount > 1; it doesn't merely
decrement the resource refcount.
+- socket_set_options() and socket_get_options() now support multicast options.
===================================
5. Changes made to existing methods
- SCANDIR_SORT_ASCENDING
- SCANDIR_SORT_DESCENDING
- SCANDIR_SORT_NONE
+ - MCAST_JOIN_GROUP
+ - MCAST_LEAVE_GROUP
+ - MCAST_BLOCK_SOURCE
+ - MCAST_UNBLOCK_SOURCE
+ - MCAST_JOIN_SOURCE_GROUP
+ - MCAST_LEAVE_SOURCE_GROUP
+ - IP_MULTICAST_IF
+ - IP_MULTICAST_TTL
+ - IP_MULTICAST_LOOP
+ - IPV6_MULTICAST_IF
+ - IPV6_MULTICAST_HOPS
+ - IPV6_MULTICAST_LOOP
+ - IPPROTO_IP
+ - IPPROTO_IPV6
g. New classes