rc_auth issue

i use following code as in radexample.c #include freeradius-client.h result = rc_auth(rh, 0, send, &received, msg); after executing the result == RC_OK and i can see in freeradius server the authentication is ok. but VALUE_PAIR received is still NULL after calling above function. and i cant retrieve the incoming attributes from radius server. am i doing something wrong? thanks for reading