Returns information about an existing socket resource. Currently returns four entries in the result array:
timed_out (bool) - The socket timed out waiting for data
blocked (bool) - The socket was blocked
eof (bool) - Indicates EOF event
unread_bytes (int) - Number of bytes left in the socket buffer
See also: socket_accept(), socket_bind(), socket_connect(), socket_listen(), socket_strerror(), and the Socket extension.