#include <contract.c>

var* Greeks[5]; 

void run()
{
	Verbose = 7|DIAG;
	set(LOGFILE);
	SaveMode = 0;
	NumYears = 1;
	assetList("OptionsIB");
	BarPeriod = 1; //mins
	NumYears = 1;
	LookBack = 0;
		
	asset("ES");
	contractUpdate ("ES-FOP-20191220",1,PUT|FUTURE);
	printf("\nPut chain loaded. Found: %d",NumContracts);
	CONTRACT* CImp = contract (PUT,160,2500);	
	contract (CImp); //sets the tradeable object, enabling the option variables..
	printf("\nStrike %f", ContractStrike); 

	var OptionPrice = contractPrice(CImp); // bid/ask average price
	printf("\nPremium %f",OptionPrice);
	
	brokerCommand(GET_GREEKS,Greeks);
	printf("\nBroker Delta is %f",Greeks[1]);	
	printf("\nBroker Theta is %f",Greeks[4]);		
}

Login 0 IB..
!Open IB Socket 2.01
!Account  xxxxxx at UTC 07-05 11:38
Load OptionsIB
!ES-FUT-20191220-ES-GLOBEX: 2996.50000 0.50000 1
!Get Future Option Chain ES-FOP-20191220-0----USD
Chain of 542 ES-FOP-20191220 contracts
Put chain loaded. Found: 542
Strike 2500.000000
!ES-FOP-20191220-2500-P-ES-GLOBEX: 19.75000 0.50000 1
Premium 19.500000
Broker Delta is 0.000000
Broker Theta is 0.000000