hi..
as Rajesh suggested, u can get ur call excercised at the end of the day. in case u want 2 square off within the day, if u dont find ur Itm call 2 b liquid, u can simultaneously sell the futures and the same strike price put of which u own the call. since the put would b otm, there is more chance of it being liquid. in case the put is of little or no value, just sell the futures and wait fr an oppertune moment 2 square off the whole position.
hope this helps
regards
Anurag