Add original unix v6

source/s1/clri.s

@@ -0,0 +1,63 @@
+/ clri -- clear inode
+
+	cmp	(sp)+,$2
+	blt	error
+	beq	1f
+	mov	4(sp),fs1
+	mov	4(sp),fs2
+1:
+	tst	(sp)+
+	mov	(sp)+,r0
+	clr	r5
+1:
+	movb	(r0)+,r1
+	beq	1f
+	mpy	$10.,r5
+	sub	$'0,r1
+	cmp	r1,$10.
+	bhis	error
+	add	r1,r5
+	br	1b
+1:
+	add	$31.,r5
+	mov	r5,r0
+	als	$-4,r0
+	mov	r0,0f
+	sys	open; fs1: filsys; 0
+	bes	error
+	mov	r0,-(sp)
+	sys	seek; 0:..; 3
+	mov	(sp),r0
+	sys	read; buf; 512.
+	mov	(sp)+,r0
+	sys	close
+	mov	r5,r0
+	als	$5,r0
+	bic	$!777,r0
+	add	$buf,r0
+	mov	$16.,r5
+1:
+	clr	(r0)+
+	sob	r5,1b
+	sys	open; fs2: filsys; 1
+	bes	error
+	mov	r0,-(sp)
+	mov	0b,0f
+	sys	seek; 0:..; 3
+	mov	(sp)+,r0
+	sys	write; buf; 512.
+	bes	error
+	sys	exit
+
+error:
+	mov	$1,r0
+	sys	write; 1f; 2f-1f
+	sys	exit
+1:
+	<error\n>
+2:
+
+filsys:	</dev/junk\0>
+.even
+	.bss
+buf:	.=.+512.