Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!usc!zaphod.mps.ohio-state.edu!van-bc!rsoft!mindlink!a464
From: a464@mindlink.UUCP (Bruce Dawson)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Problem with CreateProc & LoadSeg
Message-ID: <1677@mindlink.UUCP>
Date: 5 May 90 04:15:20 GMT
Organization: MIND LINK! - British Columbia, Canada
Lines: 40

> root@dialog.sub.org writes:
> 
> Msg-ID: <1856@dialog.sub.org>
> Posted: 5 May 90 08:23:45 GMT
> 
> Org.  : Dialog Software Development
> Person: Christian Motz
> 
> Now for the "dirty" way, and  my  question  how  dirty  this  is,  and
> whether or not there is any cleaner way to do it. My  problem  was  to
> start a process much like Execute(), only asynchronously. As far as  I
> know, AmigaDOS knows no call for something like this. I know there are
> things like ArpAsyncRun(), but I would like to  do  it  on  a " stock"
> Amiga (besides: I wonder if ArpAsyncRun() is so clean itself).
> 
> Now hold on to your seats, NetPeople, just in case this is  the  worst
> programming practice you have ever seen -- feel free to flame me,  but
> only if you know of a better, "legitimate" solution.
> 
> --
> Christian Motz                                     root@dialog.sub.org


     Two of your debatable assumptions can easily be made solid.  These are the
assumption that CreateProc() will continue to return the address of the message
port, and that A0 and D0 can continue to be set by poking into the stack.  Both
of these problems can be solved by doing a CreateProc on a short little
assembler routine which will communicate with the main program.  The assembler
routine tells the main program where it's task structure is (easily found with
FindTask(0L)) then it loads A0 and D0 (far far easier to load A0 and D0 of your
own task than somebody elses) and then it does a JSR to the code that you
actually want turned into a process.  That still leaves the messiness of
filling out pr_CIS and pr_COS, but at least two assumptions disappear.

.Bruce.
--
Bruce Dawson    Day job: Distinctive Software Inc.
                Company name: CygnusSoft Software
Work hard, rock hard, eat hard, sleep hard, grow big, wear glasses if
you need 'em.    Webb Wilder credo.