mov	parp+2,0f / more directory name to sys coll
	sys	chdir; 0:0 / exec chdir
	bec	4f / no error exit
	jsr	r5,error / go to print error
		<Bad directory\n\0>; .even / this diagnostic
4:
	clr	r1 / set r1 to zero to dkip wait
	rts	pc / and return
2:
	jsr	r5,chcom; glogin / is command login?
		br 2f / not loqin, go to fork
	sys	exec; parbuf; parp / exec login
	sys	exec; binpb; parp / or /bin/login
2: / no error return??
	sys	fork / generate sh child process for command
		br newproc / exec command with new process
	bec	1f / no error exit, old orocess
	jsr	r5,error / go to print error
		<Try again\n\0>; .even / this diaonostic
	jmp	newline / and return for next try
1:
	mov	r0,r1 / save id of child sh
	rts	pc / return to "jsr pc, docom" call in parent sh

error:
	movb	(r5)+,och / pick up diagnostic character
	beq	1f / 0 is end of line
	mov	$1,r0 / set for tty output
	sys	write; och; 1 / print it
	br	error / continue to get characters
1:
	inc	r5 / inc r5 to point to return
	bic	$1,r5 / make it even
	clr	r0 / set for input
	sys	seek; 0; 2 / exit from runcom. skip to end of
		           / input file
chcom: / has no effect if tty input
	mov	(r5)+,r1 / glogin gchdir r1, bump r5
	mov	$parbuf,r2 / command address  r2 'login'
1:
	movb	 (r1)+,r0 / is this command 'chdir'
	cmpb	(r2)+,r0 / compare command name byte with 'login'
		         / or 'chdir'
	bne	1f / doesn't compare
	tst	r0 / is this
	bne	1b / end of names
	tst	(r5)+ / yes, bump r5 again to execute login
		      / chdir
1:
	rts	r5 / no, return to exec command

putc:
	cmp	r0,$'' / single quote?
	beq	1f / yes
	cmp	r0,$'" / double quote
	beq	1f / yes