FOPEN.MAC=FOPEN.VGN;1/AU:72.
-/.ident/,.,/;25/
	.IDENT	/000025/
-/; 000024/+1
; 000025 20 Nov 1981 RVT	Add 'b' option for block mode on read
;				Fix record/file bugs
-/16./
BMODE	=	32.
-/OPTSTR:/,.+1
OPTSTR:	.ASCIZ	"rwaunb"		;Possible options (keep in this order)
OPTVAL:	.BYTE	RMODE,WMODE,AMODE,UMODE,NMODE,BMODE
-/$$FOPO::/
-/; User-/+1
	BITB	#FD.RWM,F.RACC(R0)	; BLOCK-MODE (READ ONLY)
	BEQ	5$			; NO, USE RECORD I/O

;	HE WANTS TO DO BLOCK I/O WITH HIS OWN BUFFER.
	FDRC$R	R0,#FD.RWM		; USE READ/WRITE MODE
	MOV	R4,F.BKST(R0)		; SET UP THE IOSB ADDR
	ADD	#V$IOSB,F.BKST(R0)
	BR	DOOPEN

5$:
-/20$:/
; if reading (in record mode), and not User-buffering, use locate mode
	bit	#$$wmod!$$amod,(r4)	; reading?
	bne	15$			; no, use move mode
	bit	#vf$ubf,(r4)		; user-buffering?
	bne	15$			; yes, use move mode
	fdrc$R	r0,#fd.plc		; use locate mode
15$:
-/DOOPEN:/
-/BR	$$FOPE/,.
	JMP	$$FOPE		;Sorry about that
-/; Normal exit from fopen().  Enter with r4 -> fdb./,.
; Normal exit from fopen().  Enter with r4 -> IOV.  Returns to fopen
-/MOV	V$FDB+F.VBSZ(R4),V$RBSZ(R4)/,.
	bitb	#fd.rwm,v$fdb+f.racc(r4)	; block-mode?
	bne	2$				; yes-give block size
	bit	#$$wmod!$$amod,(r4)		; reading?
	BNE	4$				; BR IF NO
	MOV	V$FDB+F.RSIZ(R4),V$RBSZ(R4)	;Get file max record size
	bne	3$				; if this is zero, then
2$:	mov	V$FDB+F.VBsz(r4),v$fdb+f.rsiz(r4); pretend fixed records
	movb	#r.fix,v$fdb+f.rtyp(r4)
4$:	MOV	V$FDB+F.VBSZ(R4),V$RBSZ(R4)	;Get Virtual block size
3$:
-/5$:/
	BITB	#FD.DIR,R0	; is it a file-oriented device?
	BEQ	7$		;No, onward
	BIS	#VF$FIL,(R4)	; YES, SAY SO
7$:
-/$$FOPT::/
-/40$:/
	BIT	#BMODE,R1	; BLOCK-MODE READ?
	BEQ	45$		; NOPE

	BIS	#UMODE!NMODE,R1	; THAT IMPLIES "NU", ALSO
	MOVB	#FD.RWM,V$FDB+F.RACC(R4)	; SET BLOCK-MODE
45$:
/