/ 
/ 
/                   FIRST PRINTING, FEBRUARY 1974
/ 
/ THE INFORMATION IN THIS DOCUMENT IS SUBJECT TO 
/ CHANGE WITHOUT NOTICE AND SHOULD NOT BE CONSTRUED
/ AS A COMMITMENT BY DIGITAL EQUIPMENT CORPORATION.
/ DIGITAL EQUIPMENT CORPORATION ASSUMES NO RESPON-
/ SIBILITY FOR ANY ERRORS THAT MAY APPEAR IN THIS
/ DOCUMENT.
/ 
/ THE SOFTWARE DESCRIBED IN THIS DOCUMENT IS FUR-
/ NISHED TO THE PURCHASER UNDER A LICENSE FOR USE ON
/ A SINGLE COMPUTER SYSTEM AND CAN BE COPIED (WITH
/ INCLUSION OF DIGITAL'S COPYRIGHT NOTICE) ONLY FOR 
/ USE IN SUCH SYSTEM, EXCEPT AS MAY OTHERWISE BE PRO-
/ VIDED IN WRITING BY DIGITAL.
/ 
/ DIGITAL EQUIPMENT CORPORATION ASSUMES NO RESPONSIBILITY
/ FOR THE USE OR RELIABILITY OF ITS SOFTWARE ON EQUIP-
/ MENT THAT IS NOT SUPPLIED BY DIGITAL.
/ 
/ COPYRIGHT (C) 1974, BY DIGITAL EQUIPMENT CORPORATION
/ 
/ 
        .EJECT
/	EDIT #1
 
/ COPYRIGHT 1973  DIGITAL  EQUIPMENT CORP., MAYNARD, MASS. U.S.A.
 
/		3 JULY 73	T.A. MURRAY
 
/FORTRAN CALLABLE RSX UTILITY ROUTINE TO EXECUTE SPY FUNCTION
 
/	CALLING SEQUENCE
/		CALL SPY (ADDRS,VALUE [,EV])
/	WHERE
/		ADDRS IS AN INTEGER WHOSE VALUE IS THE ABSOLUTE
/		ADDRESS TO BE 'SPYED'
/		VALUE IS AN INTEGER THAT RETURNS WITH THE CONTENTS
/		OF THE LOCATION SPYED, IF NO ERRORS OCCUR
/		EV IS THE INTEGER EVENT VARIABLE
 
	.GLOBL	SPY,  .DAA
 
SPY	0
	JMS*	.DAA
	JMP	ARGEND
ADDRS	0
VALUE	0
EV	0
 
ARGEND	LAC	EV	/MOVE EVENT VARIABLE ADDRESS TO SPY CAL
	DAC	SPY1
	DZM	EV	/ZERO IN CASE NOT SPECIFIED ON ANOTHER CALL
	LAC*	ADDRS	/PUT ADDRESS INTO CPB
	DAC	SPY2
	CAL	SPY0	/EXECUTE SPY FUNCTION, NO WAITFOR NEEDED
	LAC	SPY3	/GET VALUE SPYED
	DAC*	VALUE	/RETURN IT TO CALLING PROGRAM
	JMP*	SPY
 
SPY0	31
SPY1	0		/EV ADDRESS
SPY2	0		/SPY ADDRESS
SPY3	0		/RETURNED VALUE
 
	.END