V6/usr/source/s5/setgid.s

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/ C library -- setgid

/ error = setgid(uid);

setgid = 46.
.globl	_setgid, cerror

_setgid:
	mov	r5,-(sp)
	mov	sp,r5
	mov	4(r5),r0
	sys	setgid
	bec	1f
	jmp	cerror
1:
	clr	r0
	mov	(sp)+,r5
	rts	pc