Path: utzoo!utgpu!water!watmath!clyde!cbosgd!ucbvax!UIAMVS.BITNET!AWCTTYPA
From: AWCTTYPA@UIAMVS.BITNET (DAVE LYONS)
Newsgroups: comp.sys.apple
Subject: Mail from Participate at the University of Iowa
Message-ID: <8801082152.aa13383@SMOKE.BRL.ARPA>
Date: 9 Jan 88 04:04:04 GMT
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X-Unparsable-Date: Friday 08 Jan 88 6:22 PM CT

>Date:  Fri, 8 Jan 88 08:39 EST
>From:  TMPLee@DOCKMASTER.ARPA
>Subject:  ProDos Quit code

>I have a need to get a ProDos/16 binary (type $B3) launched from within
>ProDOS/8 basic.
>There is ... supposed to be an
>extension to the ProDos/8 MLI quit call that allows one to give the
>pathname of the next application.
>I assume the extension involves some change to the parmlist, but I don't
>want to try to guess what it might be -- it doesn't sound like just
>replacing the 0's with a pathname would do!)

You're not far off, although it's not something you'd be likely to guess.
The first 0 in the parameter list becomes a $EE, and the next 2 bytes are
the address of the pathname.  I believe the pathname can NOT be in $02xx,
and it MUST have the high bits turned OFF on the characters.  ProDOS 8 doesn't
care about the high bits, although they are supposed to be off anyway.

If ProDOS 16 has not been booted, this call behaves just like a boring old
QUIT call.  The file being launched can be SYS ($FF), S16 ($B3), or EXE ($B5).

>I know one can't do it directly with a PRINT
>D$;"-NEWPROGRAM" (I've tried.)

Actually, I constructed a little patch for BASIC.SYSTEM to let you do this.
I'll see if I can dig it up if anybody is interested.

--David A. Lyons  a.k.a.  DAL Systems
  PO Box 287 | North Liberty, IA 52317
  BITNET: AWCTTYPA@UIAMVS
  CI$: 72177,3233