This function must be called before you can start any multi-player session for the user. It takes the User ID pointer, which you can retrieve for a particular game pad by calling the xboxlive_user_for_pad() function, and will initialise the multi-player API.
xboxlive_matchmaking_start(user_id);
Argument Description user_id The user ID pointer to use
N/A
global.UserID =
xboxlive_user_for_pad(global.PadIndex);
xboxlive_matchmaking_start(global.UserID);
The above code gets the user ID for the given pad index and then initialises multiplayer capabilities.