.TITLE	NOLOCK
	.IDENT	/V01/
	.SBTTL	DESCRIPTION
;
;
;  COMPONENT:	NOLOCK
;
;  DATE:	27-JUN-79
;
;  AUTHOR:	GR JOHNSON
;		BATTELLE NORTHWEST
;		P O BOX 999
;		RICHLAND WA 99352
;
;  SOURCE:	MACRO-11
;
;  CALLER:	FORTRAN IV-PLUS
;
;  CALLING SEQUENCE:
;
;		CALL NOLOCK(LUN)
;
;		LUN	= INTEGER CONTAINING A LOGICAL UNIT NUMBER.
;
;
;  DESCRIPTION:
;
;	IF CALLED IMMEDIATELY BEFORE OPENING A FILE, "NOLOCK" PREVENTS THAT
;  FILE FROM BEING LOCKED IRREGARDLESS OF HOW THE TASK EXITS.
;
;  EXAMPLE:
;
;		CALL NOLOCK(2)
;		OPEN(UNIT=2,NAME='FILE.DAT',TYPE='NEW')
;
;

	.SBTTL	ENTRY POINT -- PROTECT AGAINST UNWANTED FILE LOCKING
;
;
					;
	.PSECT				;
	.MCALL	FBLOCK			; IN [11,40]F4P.MAC
	FBLOCK	X			; DEFINE FDB AND FFDB OFFSETS
					;
NOLOCK::				;
					;
	MOV	@2(R5),R2		; LUN TO R2
	JSR	PC,$FCHNL		; ADDRESS OF FFDB TO R0
	BCS	2$			; RETURN ON ERROR (INVALID LUN)
					;
	BIS	#101000,D.FDB+F.ACTL(R0)	; SET CONTROL BIT
					;
2$:	RTS	PC			; RETURN TO CALLER
	.END