Add original unix v6

source/s1/cat.s

@@ -0,0 +1,65 @@
+/ cat -- concatinate files
+
+	mov	(sp)+,r5
+	tst	(sp)+
+	mov	$obuf,r2
+	cmp	r5,$1
+	beq	3f
+
+loop:
+	dec	r5
+	ble	done
+	mov	(sp)+,r0
+	cmpb	(r0),$'-
+	bne	2f
+	clr	fin
+	br	3f
+2:
+	mov	r0,0f
+	sys	open; 0:..; 0
+	bes	loop
+	mov	r0,fin
+3:
+	mov	fin,r0
+	sys	read; ibuf; 512.
+	bes	3f
+	mov	r0,r4
+	beq	3f
+	mov	$ibuf,r3
+4:
+	movb	(r3)+,r0
+	jsr	pc,putc
+	dec	r4
+	bne	4b
+	br	3b
+3:
+	mov	fin,r0
+	beq	loop
+	sys	close
+	br	loop
+
+done:
+	sub	$obuf,r2
+	beq	1f
+	mov	r2,0f
+	mov	$1,r0
+	sys	write; obuf; 0:..
+1:
+	sys	exit
+
+putc:
+	movb	r0,(r2)+
+	cmp	r2,$obuf+512.
+	blo	1f
+	mov	$1,r0
+	sys	write; obuf; 512.
+	mov	$obuf,r2
+1:
+	rts	pc
+
+	.bss
+ibuf:	.=.+512.
+obuf:	.=.+512.
+fin:	.=.+2
+	.text
+