.TITLE 	INSHD
;
; COPYRIGHT (C) 1977
; DIGITAL EQUIPMENT CORP., MAYNARD MASS. 01754
;
;
; MODIFICATIONS:
;
;	02A -- MAKE SURE TCB'S ARE ALWAYS LINKED TO THE LEFT
;		OF THE NULL TASK IN STD
;
	.IDENT	/02A/
	.PSECT
.BLK.=.
	.MCALL	TCBDF$
	TCBDF$		;DEFINE TCB OFFSETS
.=.BLK.+524
120$:
.=.BLK.+534
	CALL	PAT1		;PERFORM TESTS IN PROPER ORDER
	BCS	130$		;IF CS LINK TCB IN HERE
	NOP
.=.BLK.+552
	BR	120$
130$:
.=.BLK.
	.PSECT	$$PAT1
$$PAT1=.
PAT1:	TST	T.TCBL(R5)	;IS THIS THE NULL TASK?
	SEC			;ASSUME TST BRANCHES
	BEQ	10$		;IF EQ YES
	CMPB	T.DPRI(R5),$TCB+T.DPRI	;NEW TASK HIGHER PRIORITY?
10$:	RETURN
.=$$PAT1
	.END