.TITLE	BLKFIL - BLANK FILL STRING
	.IDENT	/02MAY7/	;13:30:00  LV
;	.ENTRY	BLKFIL	BLANK FILL STRING
;+
; B L K F I L
; 
; PURPOSE:	EXAMINE A CHARACTER STRING AND CONVERT
;		ALL NULL BYTES TO BLANKS.
;
; INTERFACE:	CALLING SEQUENCE: (FORTRAN-CALLABLE SUBROUTINE)
;			CALL BLKFIL (STRING,NBYTES)
;
;		INPUT:	STRING = ADDRESS OF STRING
;			NBYTES(INTEGER) = NUMBER OF BYTES IN STRING
; LANGUAGE:	MACRO-11
;-
; REVISIONS:
; 01-JAN-75	RK	WRITTEN
; 10-SEP-76	SS	MAKE INDEPENDENT OF SPECIAL MACROS
; 02-MAY-77	LV	UPDATED TO CONFORM TO STANDARDS
;
	.MCALL	RETURN
BLKFIL::
	MOV	R0,-(SP)
	MOV	R1,-(SP)
	MOV	2(R5),R0	;ADDRESS OF STRING
	MOV	@4(R5),R1	;BYTE COUNT
	BEQ	DONE
10$:	TSTB	(R0)		;IS THIS BYTE A ZERO?
	BNE	20$		;NO,  GET NEXT BYTE
	MOVB	#40,(R0)	;YES, MAKE IT A BLANK
20$:	INC	R0		;POINT TO NEXT BYTE
	SOB	R1,10$		;BRANCH IF MORE
DONE:	MOV	(SP)+,R1
	MOV	(SP)+,R0
	RETURN
	.END