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C.S.M.P. Digest             Sun, 04 Dec 94       Volume 3 : Issue 73

Today's Topics:

        ? THINK Pascal: calling code
        Any science to segmenting?
        Plug-Ins w- CFM
        Saving a PICT to a file - how?
        Sprite Animation Toolkit 2.3a1
        UPP's & calling completion procs



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-------------------------------------------------------

>From [e-mail] (Ashley A Thomas)
Subject: ? THINK Pascal: calling code
Date: Fri, 18 Nov 1994 16:51:15 +1100
Organization: little to none

Could someone tell me where to find a good desription of how to write and
use code you call from inside your program with THINK Pascal in the same
way C programs can by calling a routine by passing a pointer to it.

e.g. running code in a resource given its handle (like dnr); or passing a
pointer to a procedure to be called somewhere else.

Thanks!
ASE

--

Ashley A Thomas
Email: [e-mail]

+++++++++++++++++++++++++++

>From [e-mail] (Ingemar Ragnemalm)
Date: 20 Nov 1994 12:59:59 GMT
Organization: (none)

[e-mail] (Ashley A Thomas) writes:

>Could someone tell me where to find a good desription of how to write and
>use code you call from inside your program with THINK Pascal in the same
>way C programs can by calling a routine by passing a pointer to it.

>e.g. running code in a resource given its handle (like dnr); or passing a
>pointer to a procedure to be called somewhere else.

The following inline function is taken from TransSkel.p:

    procedure CallpInt (myInt: integer; myProc: ProcPtr);

{ Two calls use integer as one parameter arguments.  This procedure handles    }
{ both of them.                                                                            }

    inline
        $205f,     {movea.l  (a7)+,a0        ; (a0) is a ptr to string, 4(a0) is mode}
        $4e90;


By calling CallpInt, you call the procedure that myProc points to, with myInt
as argument. Unfortunately, there is no type-checking done, so you are
responsible for sending a pointer to a procedure that takes exactly the
arguments you assume.

myProc can be created by taking the address of the procedure (e.g.
myProc := @MyProcedure;), or by dereferencing a handle to a code resource
(after locking it!), e.g. something like:

myCode := GetResource('CODE', 9999);
if myCode = nil then
    HandleError
else begin
    HLock(myCode);
    myProc := myCode^;
end;

You can change the above inline to any other argument list simply by adding
or replacing arguments.

Calling procedure pointers should really be built-in into Pascal, just as it
is in Modula2, so we didn't have to do this kind of workarounds. Most of all,
I want type checking on my procedure pointers. Perhaps we could convince
MetroWerks to add it?

--
- -
Ingemar Ragnemalm, PhD
Image processing, Mac shareware games
E-mail address: [e-mail] or [e-mail]

---------------------------

>From [e-mail] (Keith MacDonald)
Subject: Any science to segmenting?
Date: 8 Nov 1994 04:23:04 GMT
Organization: ECE - Concordia University


Should I be practising any science in determining which procedures are
grouped into the same segments when I code or is there little/no
overhead in jumping from one segment to another?

Cheers,
Keith
___________________________________________________________________________
 Keith MacDonald                                       Computer Engineering
 [e-mail]                             Concordia University
 http://www.ece.concordia.ca/~ikb_macd/addr.html       Montreal, QC, Canada

+++++++++++++++++++++++++++

>From [e-mail] ( nick.c )
Date: Tue, 08 Nov 1994 01:05:54 -0500
Organization: The Pitt, Chemistry

In article <39muf8$[e-mail]>, [e-mail]
(Keith MacDonald) wrote:

> Should I be practising any science in determining which procedures are
> grouped into the same segments when I code or is there little/no
> overhead in jumping from one segment to another?

   My understanding is a segment is swapped into memory as a whole.
     So, (and I'm reasoning here, not speaking with any authority)
     it would make sense to me to group functions that call each
     other together into the same segment.  Try and make each segment
     as "self contained" as possible (realizing that no segment
     could be entirely self contained - or it would be unnecessary
     to 'main').  This would minimize the efficiency loss of swapping
     in segments.  'Course with the modern memory structure of the
     Mac, I'm not sure this "swapping" ocurrs any longer... dunno.


 Internet: [e-mail]            _/   _/  _/  _/_/_/   _/   _/
   eWorld: nick                     _/_/ _/  _/  _/   _/  _/_/_/
      CIS: 71232,766               _/ _/_/  _/  _/       _/ _/
     http://www.pitt.edu/~nick/   _/   _/  _/   _/_/_/  _/   _/


+++++++++++++++++++++++++++

>From [e-mail] (Kevin W. Ramer)
Date: Wed, 09 Nov 1994 09:07:44 -0600
Organization: University of Alabama at Birmingham

In article <[e-mail]>,
[e-mail] ( nick.c ) wrote:
>
> > Should I be practising any science in determining which procedures are
> > grouped into the same segments ?

>    My understanding is a segment is swapped into memory as a whole.
>      So, (and I'm reasoning here, not speaking with any authority)
>      it would make sense to me to group functions that call each
>      other together into the same segment.  Try and make each segment
>      as "self contained" as possible (realizing that no segment
>      could be entirely self contained - or it would be unnecessary
>      to 'main').  This would minimize the efficiency loss of swapping
>      in segments.  'Course with the modern memory structure of the
>      Mac, I'm not sure this "swapping" ocurrs any longer... dunno.

A couple of additional points to be made are 1) if you wish to have
segments  unloaded, do so from the main segment. Typically, calling
UnloadSeg each time through your event loop.  2) If you don't stick
to 1 be sure to never unload segments earlier in the calling chain !
For example, main calls A which calls B (each in different segments)
_do not_ UnloadSeg(A) while in B.  Makes for nasty crashes.

--
Kevin W. Ramer                   [e-mail]
Programmer Analyst
Neurobiology Research Center
University of Alabama at Birmingham

+++++++++++++++++++++++++++

>From [e-mail] (Pete Gontier)
Date: Wed, 09 Nov 1994 09:42:45 -0800
Organization: Novell, Inc., Walnut Creek/Macintosh Site

In article <[e-mail]>,
[e-mail] ( nick.c ) wrote:

> 'Course with the modern memory structure of the
> Mac, I'm not sure this "swapping" ocurrs any longer... dunno.

Yes, it does. The Modern Memory Manager just has better (read: faster)
heap management. It doesn't try to tell anyone what to do with individual
heap blocks, which of course are what contain each code segment. You may
be thinking of the Power Mac code model, which has a new paging scheme for
code fragments in the data fork, assuming VM is turned on.

I might as well add, now that I have followed up, that a successful
segmentation strategy has to be planned ahead of time. The good news is
that the strategy has a lot in common with good engineering practice
regardless of segmentation, so if you are a good engineering citizen, you
probably *accidentally* planned your segmentation strategy ahead of time
:-). More specifically, if you have narrow entry points into your
functional sub-systems, you can simply put each sub-system into its own
segment and unload it when it's not needed.

--
 The views expressed here do not necessarily reflect those of my employer.

+++++++++++++++++++++++++++

>From [e-mail] (Rick Holzgrafe)
Date: Tue, 8 Nov 1994 18:41:38 GMT
Organization: Semicolon Software

In article <39muf8$[e-mail]>, [e-mail]
(Keith MacDonald) wrote:

> Should I be practising any science in determining which procedures are
> grouped into the same segments when I code or is there little/no
> overhead in jumping from one segment to another?

Segments exist mainly for memory management purposes: they allow you to
group relevant portions of your code into chunks which do not have to be
kept in memory when they are not in use. For example, your initialization
code runs only once, when the app starts up: put it all into a segment,
and unload it when initialization is complete. You may have printing code
which can be cleanly separated from the rest of your code; there's no need
for it to be in memory when the user isn't printing -- and so on. This
makes more efficient use of your heap and allows your app to run in less
memory.

There is a slight performance hit when making calls across segments,
because they must pass through the jump table. Normally it's not worth
worrying about, but I wouldn't call segment B from inside a tight, long,
hopefully-fast loop in segment A. If you segment your code functionally,
this will generally not happen anyway.

You should be aware that segments are loaded automagically the first time
any function in them is called, but they are never unloaded unless you do
so specifically in your code. This has a couple of effects. One effect is
that *any* routine can move memory if it is in an unloaded segment when
you call it, because its segment will be loaded into your heap before the
routine can be called. Another effect is that you need to be intelligent
about unloading your segments if you want to reap the memory-management
benefits. A common practice is to keep your main event loop in segment 0
(that is, the one that contains your main routine), and each time through
the event loop, unload every other segment you've got. Unloading a segment
doesn't force it from memory, it just frees it to move in the heap and to
be purged if needed when memory gets low. Commonly used segments will
therefore incur no serious performance penalty from being repeatedly
unloaded unless memory is low; the user can then improve performance by
allocating more memory to the app, if more memory is available.

Exceptions to the automagical loading of segments: returns from
subroutines do *not* force loading of segments, and segments cannot be
loaded at interrupt level. Never unload a segment if your call stack
contains pointers into it, or if you are using interrupt-level callbacks
(e.g. from VBL or slot queues, async sound calls, async network calls, and
the like) to routines in the segment. (I got into trouble once by calling
my main event handler from a routine in a different segment; the main
event handler was innocently unloading the segment that called it.
Intermittently [whenever something stirred up the heap just wrong] it
would crash when trying to return to the unloaded segment.)

Segments can be marked "preload" in the resource fork if you want them
loaded at startup; if you never explicitly unload them, then they'll
always be there when you need them.

Hope this helps.

-- Rick Holzgrafe, a member of the Taligentsia
   [e-mail]
   [e-mail]

+++++++++++++++++++++++++++

>From [e-mail] (curreyr)
Date: 19 Nov 1994 10:16:54 GMT
Organization: Northwest Nexus Inc.

In article <[e-mail]>
[e-mail] (Rick Holzgrafe) writes:

> You should be aware that segments are loaded automagically the first time
> any function in them is called, but they are never unloaded unless you do
> so specifically in your code. This has a couple of effects. One effect is
> that *any* routine can move memory if it is in an unloaded segment when
> you call it, because its segment will be loaded into your heap before the

Another "effect" is that it can FAIL to load if there isn't room in the
heap for the segment. This can be bad news to your users. If you ignore
this fact, and the segment fails to load, your code had better handle
this fact. But handling the failure is a pain in the @#$@. How many
apps can you name that handle low memory situations reliably?

My suggestion would be to use a modern application framework that hides
the ugly details of segmentation loading/unloading and follow the
advice others have given on segmenting your code. MacApp maintains a
reserve in order to insure that there is always going to be memory
available for that code segments to be loaded and could be used as an
example if you want to "roll your own".

-Robert Currey

---------------------------

>From [e-mail] (Matt Daw)
Subject: Plug-Ins w- CFM
Date: Wed, 16 Nov 1994 03:50:10 GMT
Organization: Alias Research Inc.

Has anybody implemented a way to do plug-ins (ala PhotoShop) with the Code
Fragment Manager? If so, what is the best way of doing this?

- ---------------------
| Matt Daw            |
| Alias Research Inc. |
- ---------------------

+++++++++++++++++++++++++++

>From [e-mail] (Jon W{tte)
Date: Sat, 19 Nov 1994 15:40:34 +0100
Organization: The Conspiracy

In article <mdaw-1511942250100001@192.75.21.44>,
[e-mail] (Matt Daw) wrote:

>Has anybody implemented a way to do plug-ins (ala PhotoShop) with the Code
>Fragment Manager? If so, what is the best way of doing this?

It's REALLY easy. You just load the fragment from disk, and get
the value of the symbol you want (like "main") and call it as a
function pointer. NO PAIN!

Unless you're on the 68K, in which case it's #$GUffaw

<What was that?>
<The manager for the CFM 68K, tiring of the flames and
putting them out>
<Oh!>

Cheers,

                    / h+


--
  Jon W‰tte ([e-mail]), Hagagatan 1, 113 48 Stockholm, Sweden
  "Psychotherapist" - "Psycho-The-Rapist"
   Pure coincidence? You decide!


---------------------------

>From [e-mail] (Andrew Greenshields)
Subject: Saving a PICT to a file - how?
Date: 16 Nov 1994 00:43:29 GMT
Organization: Clemson University


  I have finally got my text file to convert to a nice infra-red image
which I now have in the format of a PICT.  However, when I try to save
this PICT as a file I am running into trouble.  I am using
GetHandleSize to find out how big the PICT is and then I am using
SFWrite to write the data to a file.  I am using *thePict as the
pointer to the data, where thePict is of type PicHandle.  When I try
and look at this file using Photoshop it tells me there is a problem
reading this file.  What am I doing wrong?

  Any help would be greatly appreciated.


Thanks in advance,

Andy

--
  Andrew J. Greenshields N3IGS    |  Some people can tell what time it is by
  [e-mail]             |  looking at the Sun, but I have never been
  USPA C-24393                    |  able to make out the numbers.
- ---------------------***STANDARD DISCLAIMERS APPLY***------------------------

+++++++++++++++++++++++++++

>From [e-mail] (Brian L. Matthews)
Date: 16 Nov 1994 18:14:08 GMT
Organization: NWNEXUS, Inc. - Making Internet Easy

In article <3abkjh$[e-mail]>,
Andrew Greenshields <[e-mail]> wrote:
| I am using GetHandleSize to find out how big the PICT is and then I
|am using SFWrite to write the data to a file.

A PICT file starts with a 512-byte header before the actual PICT data.
This header is for use by applications, and as far as I know, there aren't
any standards for what goes in there, except one.  If it's all zeroes,
you're fine.  So, before calling FSWrite to put the picture data in the
file, do a:

    err = SetFPos (fRefNum, 1, 512);

If you've just created the file, this will effectively put 512 0s at
the start of the file.  Note that if you're writing to an existing file,
you may actually have to do an FSWrite of 512 0s to ensure they're there.

Brian
--
Brian L. Matthews                    [e-mail]
  "Look past the ghost that hides Hell's treasures." -Sky Cries Mary

+++++++++++++++++++++++++++

>From [e-mail] (Lawrence D'Oliveiro, Waikato University)
Date: 17 Nov 94 16:59:07 +1300
Organization: University of Waikato, Hamilton, New Zealand

In article <3adi5g$[e-mail]>, [e-mail] (Brian L. Matthews) writes:
>
> A PICT file starts with a 512-byte header before the actual PICT data.
> This header is for use by applications, and as far as I know, there aren't
> any standards for what goes in there, except one.  If it's all zeroes,
> you're fine.  So, before calling FSWrite to put the picture data in the
> file, do a:
>
>     err = SetFPos (fRefNum, 1, 512);
>
> If you've just created the file, this will effectively put 512 0s at
> the start of the file.

No, it will not. You must explicitly write 512 bytes of zeroes in all cases.

Lawrence D'Oliveiro                       fone: [phone]
Computer Services Dept                     fax: [phone]
University of Waikato            electric mail: [e-mail]
Hamilton, New Zealand    37^ 47' 26" S, 175^ 19' 7" E, GMT+13:00

+++++++++++++++++++++++++++

>From [e-mail] (Brian L. Matthews)
Date: 17 Nov 1994 18:26:54 GMT
Organization: NWNEXUS, Inc. - Making Internet Easy

In article <[e-mail]>,
Lawrence D'Oliveiro, Waikato University <[e-mail]> wrote:
|>     err = SetFPos (fRefNum, 1, 512);
|> If you've just created the file, this will effectively put 512 0s at
|> the start of the file.
|No, it will not. You must explicitly write 512 bytes of zeroes in all cases.

Argh.  Lawrence is, of course, absolutely right.  I always seem to get
Unix and the Mac confused in cases like this.  Anyway, I was actually
wrong twice.  First, SetFPos will fail if you attempt to set the file
position beyond the end of file.  And second, if you use SetEOF before
the SetFPos, it doesn't fill with 0s.  So while I was right about needing
the 512 0s, I screwed up how to get them there. :-)

Brian
--
Brian L. Matthews                    [e-mail]
  "Look past the ghost that hides Hell's treasures." -Sky Cries Mary

+++++++++++++++++++++++++++

>From [e-mail] (Andrew Greenshields)
Date: 18 Nov 1994 01:32:04 GMT
Organization: Clemson University

In article <3ag79e$[e-mail]> [e-mail] (Brian L. Matthews) writes:
>In article <[e-mail]>,
>Lawrence D'Oliveiro, Waikato University <[e-mail]> wrote:

  Thankyou both, I can now successfully save my PICTs to files!

Andy


--
  Andrew J. Greenshields N3IGS    |  Some people can tell what time it is by
  [e-mail]             |  looking at the Sun, but I have never been
  USPA C-24393                    |  able to make out the numbers.
- ---------------------***STANDARD DISCLAIMERS APPLY***------------------------

+++++++++++++++++++++++++++

>From [e-mail] (Keith Rollin)
Date: Sun, 20 Nov 1994 22:56:08 -0800
Organization: Apple ][ -> Mac -> Taligent -> Newton -> Windows?

In article <3abkjh$[e-mail]>, [e-mail]
(Andrew Greenshields) wrote:

>  I have finally got my text file to convert to a nice infra-red image
>which I now have in the format of a PICT.  However, when I try to save
>this PICT as a file I am running into trouble.  I am using
>GetHandleSize to find out how big the PICT is and then I am using
>SFWrite to write the data to a file.  I am using *thePict as the
>pointer to the data, where thePict is of type PicHandle.  When I try
>and look at this file using Photoshop it tells me there is a problem
>reading this file.  What am I doing wrong?

PICT files begin with a 512 byte header (documented in an old Technote and
in NIM:Imaging with QuickDraw). You don't mention that you are providing
for this header, so that might be your problem.

The 512 byte header is for application-defined purposes. If you don't need
to use it, you should clear it out (set it to zero) so as not to confuse
another application that may try interpreting it.

- --------------------------------------------------------------------------
Keith Rollin --- Phantom Programmer --- Apple Computer, Inc. --- Team Newton
"I say, let's write "wacko" on all the rocks and be done with it."

---------------------------

>From [e-mail] (Ingemar Ragnemalm)
Subject: Sprite Animation Toolkit 2.3a1
Date: 19 Nov 1994 18:12:06 GMT
Organization: (none)

Sprite Animation Toolkit 2.3, alpha version 1, is now available by
ftp from ftp.uu.net, in the /tmp directory, as sat23a1.hqx. It will
probably not remain there for more than a week.

Sprite Animation Toolkit is a programming library for making sprite-based
animations (e.g. games). It includes a large number of demos, ranging from
trivially simple to a complete game. It has been used for producing over
a dozen released games.

This version works with CodeWarrior (Pascal or C, not PPC yet) as well
as the Think compilers. (Not MPW. Sorry.) Several new features have been
added, and a few changes have been made to make it faster, use less
memory and be more foolproof.

This is an alpha version. It is not thoroughly tested. All demos work just
fine on all systems I have been able to try them on, but I need help to find
out if there are any serious bugs left.

--
- -
Ingemar Ragnemalm, PhD
Image processing, Mac shareware games
E-mail address: [e-mail] or [e-mail]

---------------------------

>From [e-mail] (David Gladstone)
Subject: UPP's & calling completion procs
Date: Thu, 17 Nov 1994 08:55:53 +1200
Organization: University of Auckland, New Zealand.


Hi.  I have been having some conceptual problems with UPPs.  I am writing
a Catalog Service Access Module driver which needs to call a completion
routine.

I have been getting confused about how things work (especially with CFM68K
on the horizon).  I wrote the following initially as a series of questions
and (as is often the case) managed to find plausible answers just by trying
to phrase the questions - so I have stated what I understand instead.  How
accurate is my version of the story below.  It has been a while since I read
develop 17 (16?) "Making the Leap to PowerPC"...


The way I figure it, there are several situations that could occur at runtime
for my driver:

1. I am 68K code and the completion routine field is a ProcPtr
2. I am 68K code and the completion routine field is a UPP (either PPC or 68K
   code fragment)
3. I am PPC code and the completion routine field is a UPP (either PPC or 68K
   code fragment)
4. I am PPC code and the completion routine field is a ProcPtr (from a 68K,
   non CFM68K app)


Case 1 would occur when we are running on a PPC in emulation or on a 68K
machine and an old piece of software calls me.  Since my code is 68K and
I don't have CFM68K at my disposal the only option I have is to call
the routine as if it were a ProcPtr (which is fine in this case).


Case 2 would occur when a 68K version of the driver is running in emulation
on a PPC or it is running on a 68K machine with CFM68K installed.

It would not be so difficult if CFM68K existed - I could use it to dispatch
all UPP calls and it would determine whether the pointer was a real UPP or
not.  However, without using CFM68K for the 68K version of the driver I
have to call any value in the completion routine field of the parameter
block as if it were a ProcPtr.  This means that I will be jumping to the
routine descriptor rather than the routine itself.  I presume that
NewRoutineDescriptor() must put 68K code at the beginning of all routine
descriptors to handle this.



Case 3 would occur when a PPC version of the driver is called by a CFM
aware 68K or PPC app.

In this case just call CallUniversalProc to dispatch the call.



Case 4 would occur when a PPC version of the driver is called by an old
non-CFM68K application.

This must be handled by the Code Fragment Manager.  If you call
CallUniversalProc with a ProcPtr it figures out that the address in
memory is not a routine descriptor and therefore should execute it as
68K code.





Is it really that simple?


David Gladstone.

_________________________________________________________________________
David Gladstone : Computer Science Department, University of Auckland, NZ
[e-mail] : Ph. [phone] x 5336 : Fax: [phone]
_________________________________________________________________________
                      "Give blood... Play Hockey."


+++++++++++++++++++++++++++

>From [e-mail] (Brian Stern)
Date: 17 Nov 1994 05:03:19 GMT
Organization: The University of Texas at Austin, Austin, Texas

In article <[e-mail]>,
[e-mail] wrote:

< Hi.  I have been having some conceptual problems with UPPs.  I am writing
< a Catalog Service Access Module driver which needs to call a completion
< routine.

  I presume that
< NewRoutineDescriptor() must put 68K code at the beginning of all routine
< descriptors to handle this.

Not Exactly.  If you're on a PowerMac, drop into macsBug and type 'il
CopyBits'.  CopyBits is native.  What you'll see looks something like
this:

            000C12AC   TB         E                 | AAFE
            000C12AE   BTST       D3,D0             | 0700
            000C12B0   ORI.B      #$00,D0           | 0000 0000
            000C12B4   ORI.B      #$00,D0           | 0000 0000
            000C12B8   ORI.B      #$BFC0,D3         | 0003 BFC0
            000C12BC   ORI.B      #$04,D1           | 0001 0004
            000C12C0   ORI.B      #$2C10,A3         | 000B 2C10
            000C12C4   ORI.B      #$00,D0           | 0000 0000
            000C12C8   ORI.B      #$00,D0           | 0000 0000
            000C12CC   ORI.B      #$A8EF,D0         | 0000 A8EF

What you're looking at is the routine descriptor for Copybits.  Notice
that the first word is AAFE.  That's the mixedmodemagic trap.  So when you
call copybits you're actually jumping to the mixedmodemagic trap.  It
knows the location of the rest of the routine descriptor and gets the
information that it needs to jump to the appropriate code in the
appropriate mode.

< Is it really that simple?

Pretty much.
If you're 68K then all you know about are procptrs.  If you're PPC then
you MUST use CallUniversalProc.  CallUniversalProc works correctly if the
code it's pointing to is a routine descriptor or is 68K code.

<
<
< David Gladstone.
<
< _________________________________________________________________________
< David Gladstone : Computer Science Department, University of Auckland, NZ
< [e-mail] : Ph. [phone] x 5336 : Fax: [phone]
< _________________________________________________________________________
<                       "Give blood... Play Hockey."

--
Brian  Stern  :-{)}
Toolbox commando and Menu bard
[e-mail]

+++++++++++++++++++++++++++

>From [e-mail] (Bill Hofmann)
Date: Thu, 17 Nov 1994 17:54:50 GMT
Organization: Fresh Software

In article <[e-mail]>,
[e-mail] wrote:
>....
> The way I figure it, there are several situations that could occur at runtime
> for my driver:
>
> 1. I am 68K code and the completion routine field is a ProcPtr
> 2. I am 68K code and the completion routine field is a UPP (either PPC or 68K
>    code fragment)
> 3. I am PPC code and the completion routine field is a UPP (either PPC or 68K
>    code fragment)
> 4. I am PPC code and the completion routine field is a ProcPtr (from a 68K,
>    non CFM68K app)
>....
> Is it really that simple?
Yes, it is.  Look at almost any header.  The proper way to call the
completion proc is to define a set of macros (I bet they're already
defined for CSAMs):
#if ROUTINEDESCRIPTORS
#define CallCSAMCompletionProc(proc, foo, bar)    \
        CallUniversalProc(proc, uppCSAMCompletionProcInfo, (foo), (bar))
#else
#define CallCSAMCompletionProc(proc, foo, bar)     \
        ((proc)((foo), (bar))
#endif
like so, look for more detail in any header.  Just use CallCSAMCompletionProc()
in your code.

-Bill

--
Bill Hofmann                                  [e-mail]
Fresh Software and Instructional Design       voice: [phone]
1640 San Pablo Ave #C, Berkeley CA 94702 USA  fax:   [phone]

+++++++++++++++++++++++++++

>From [e-mail] (Jon W{tte)
Date: Fri, 18 Nov 1994 09:26:57 +0100
Organization: The Conspiracy

In article <[e-mail]>,
[e-mail] (David Gladstone) wrote:

>1. I am 68K code and the completion routine field is a ProcPtr
>2. I am 68K code and the completion routine field is a UPP (either PPC or 68K
>   code fragment)

Here, just blithely jump to the address. Things will work,
because the 68K code in the UPP includes the _MixedModeMagic
trap.

>3. I am PPC code and the completion routine field is a UPP (either PPC or 68K
>   code fragment)
>4. I am PPC code and the completion routine field is a ProcPtr (from a 68K,
>   non CFM68K app)

If the API says this is now a UPP field, then you have to call
through with CallXXX() which will make sure that everything
works.

However, the way that the 68K CFM works (totally new glue
libraries; can't use old headers) and PPC emulation works, the
68K CFM model will look just like the PPC model, i e do what
you'd do on the PPC and you will be fine.

That there is no architecture for CFM driver (and even less for
PPC drivers) probably has something to do with it as well.
Safest bet would be to write it in plain, non-CFM 68K code
until the new driver architecture rolls around.

Cheers,

                    / h+


--
  Jon W‰tte ([e-mail]), Hagagatan 1, 113 48 Stockholm, Sweden

"When I started hacking, we didnπt have ones. We had to make do with zeros."
    ã Overheard by Andrew Craze


+++++++++++++++++++++++++++

>From [e-mail] (Bruce Hoult)
Date: Sat, 19 Nov 1994 01:43:04 +1300 (NZDT)
Organization: (none)

[e-mail] (Brian Stern) writes:
>   I presume that
> < NewRoutineDescriptor() must put 68K code at the beginning of all routine
> < descriptors to handle this.
>
> Not Exactly.  If you're on a PowerMac, drop into macsBug and type 'il
> CopyBits'.  CopyBits is native.  What you'll see looks something like
> this:
>
>             000C12AC   TB         E                 | AAFE
>             000C12AE   BTST       D3,D0             | 0700
>             000C12B0   ORI.B      #$00,D0           | 0000 0000
>             000C12B4   ORI.B      #$00,D0           | 0000 0000
>             000C12B8   ORI.B      #$BFC0,D3         | 0003 BFC0
>             000C12BC   ORI.B      #$04,D1           | 0001 0004
>             000C12C0   ORI.B      #$2C10,A3         | 000B 2C10
>             000C12C4   ORI.B      #$00,D0           | 0000 0000
>             000C12C8   ORI.B      #$00,D0           | 0000 0000
>             000C12CC   ORI.B      #$A8EF,D0         | 0000 A8EF
>
> What you're looking at is the routine descriptor for Copybits.  Notice
> that the first word is AAFE.  That's the mixedmodemagic trap.  So when you
> call copybits you're actually jumping to the mixedmodemagic trap.  It
> knows the location of the rest of the routine descriptor and gets the
> information that it needs to jump to the appropriate code in the
> appropriate mode.

You're running an old version of Macsbug.  My 6100 says:

            000B6FAC   _MixedModeMagic                       ; AAFE       | AAFE
            000B6FAE   BTST       D3,D0                                   | 0700
            000B6FB0   ORI.B      #$00,D0                                 | 0000 0000
            000B6FB4   ORI.B      #$00,D0                                 | 0000 0000
            000B6FB8   ORI.B      #$BFC0,D3                               | 0003 BFC0
            000B6FBC   ORI.B      #$04,D1                                 | 0001 0004
            000B6FC0   ORI.B      #$8A60,A2                  ; '`'        | 000A 8A60
            000B6FC4   ORI.B      #$00,D0                                 | 0000 0000
            000B6FC8   ORI.B      #$00,D0                                 | 0000 0000
            000B6FCC   ORI.B      #$A8EF,D0                               | 0000 A8EF

-- Bruce




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