;	SUBROUTINE CONCAT(A,B,OUT{,LEN{,ERR}})
;
; CONCATENATES STRINGS A(LEFT) AND B(RIGHT) GIVING STRING OUT.
; LEN IS THE MAXIMUM LENGTH OF OUT, AND ERR IS SET .TRUE. IF
; THIS IS EXCEEDED, IN WHICH CASE THE STRING IS TRUNCATED.

	.TITLE	CONCAT
	.IDENT	/V2/
	.PSECT

	.GLOBL	CONCAT

CONCAT:	MOV	(R5)+,R3
	MOV	(R5)+,R1
	MOV	(R5)+,R2
	MOV	(R5)+,R0
	CMPB	#3 ,R3
	BEQ	CONCTA 
	MOV	@(R5)+,R4
CONCTH:	MOVB	(R1)+,(R0)+
	BEQ	CONCTG 
	DEC	R4
	BNE	CONCTH 
CONCTD:	CLRB	(R0)+
	CMPB	#5 ,R3
	BHI	CONCTB 
	TSTB	(R1)
	BNE	CONCTF 
	TSTB	(R2)
	BEQ	CONCTB 
CONCTF:	MOVB	#177777 ,@(R5)+
CONCTB:	RTS	PC
CONCTG:	CMPB	-(R0),-(R1)
CONCTC:	MOVB	(R2)+,(R0)+
	BEQ	CONCTB 
	DEC	R4
	BNE	CONCTC 
	BR	CONCTD 
CONCTA:	MOVB	(R1)+,(R0)+
	BNE	CONCTA 
	DEC	R0
CONCTE:	MOVB	(R2)+,(R0)+
	BNE	CONCTE 
	RTS	PC

	.END