what's the definition of struct USER_INFO in RL_TCPnet

Hi guys,
Since the single TCP Connection is success using RL_TCPnet firmware, I want to keep go in the Multiple TCP Connections. The follow link is the description of Multiple TCP Connections on KEIL.

www.keil.com/.../rlarm_tn_tcp_mulconn.htm

In the link, there are some source code for the demo of Multiple TCP Connections. There are some struct and macro i can't find the definition in the installation files.
Like:

struct USER_INFO
macro USER_STATE_ERROR; USER_STATE_IDLE; USER_STATE_RESERVED; USER_STATE_ACTIVE; USER_FLAG_FOPENED;
function user_fclose; free_mem

Please give me some hints, thanks very much!!!