V7/usr/src/libc/sys/ioctl.s

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/ C library -- ioctl

/ ioctl(fdes, command, arg)
/ struct * arg;
/
/ result == -1 if error

.globl	_ioctl, cerror
.ioctl	= 54.

_ioctl:
	mov	r5,-(sp)
	mov	sp,r5
	mov	4(r5),0f
	mov	6(r5),0f+2
	mov	8(r5),0f+4
	sys	0; 9f
	bec	1f
	jmp	cerror
1:
	mov	(sp)+,r5
	clr	r0
	rts	pc
.data
9:
	sys	.ioctl; 0:..; ..; ..