After receiving a user's authentication data, and passing it to SendUserConnectAndAuthenticate, use this function
to determine if the user owns downloadable content specified by the provided AppID.
public static EUserHasLicenseForAppResult UserHasLicenseForApp(CSteamID steamID, AppId_t appID) { InteropHelp.TestIfAvailableGameServer(); return NativeMethods.ISteamGameServer_UserHasLicenseForApp(steamID, appID); }