.TITLE IDZERO
/ 
/ 
/                   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
/COPYRIGHT 1970, DIGITAL EQUIPMENT CORP., MAYNARD, MASS.
	/EDIT 1    7--2--70
	/LOGICAL OR INTEGER FUNCTION WITH INTEGER ARGUMENT
	/IDZERO(N)
	/IF N=0, DON'T CHECK
	/IF N IS NOT EQUAL 0, CHECK
	/IF N=0, A ZERO RESULT RETURNED (FALSE)
	/IF N IS NOT EQUAL 0, TRUE (777777) RETURNED IF TEST IS POSITIVE
	/IF N IS NOT EQUAL TO 0, FALSE(0) RETURNED IF TEST IS NEGATIVE
	.GLOBL IDZERO,.DZERO,.DA
IDZERO	0
	JMS* .DA
	JMP .+2
IDZ1	0			/ADDRESS OF INTEGER ARGUMENT
	LAC* IDZ1		/GET ARGUMENT
	SNA			/TEST ARG.
	JMP* IDZERO		/EXIT WITH ZERO AC
	LAC* .DZERO		/TEST FLAG FOR DIVISION BY ZERO
	SZA!CMA			/YES OR NO?
	JMP* IDZERO		/NO. EXIT WITH ZERO AC
	DAC* .DZERO		/YES. REINIT FLAG TO 777777
	JMP* IDZERO		/EXIT WITH 777777 AC
	.END