Celestin Apprentice 5/Apprentice-Release5.iso/Information/CSMP Digest/volume 3/csmp-digest-v3-148

Text File | 1996-06-10 | 34KB | 978 lines

C.S.M.P. Digest             Sun, 02 Jun 96       Volume 3 : Issue 148

Today's Topics:

        Alt.Sources.Mac Archive Updated...
        EventAvail alternatives wanted
        Finding Apps In Desktop DB?
        Finding the caller of a CFM sharedlib?
        If you don't want to *wait* for events...
        MacFS: A Portable Macintosh Filesystem
        Serial port in use?
        Tiny Object Framework anyone?
        Web page for Macsbug tips
        [SOURCE] MicroMovie (was: HELP! with QuickTime)



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

>From [e-mail]
Subject: Alt.Sources.Mac Archive Updated...
Date: 16 May 1996 16:21:38 -0700
Organization: Alt.Sources.Mac Archive

I have recently finished updating a good portion of the alt.sources.mac
archive.  Stop by for a visit and see what's new...

  <ftp://ftp.ambrosiasw.com/pub/alt.sources.mac/>
  <http://www.ambrosiasw.com/alt.sources.mac/>

Dave Nebinger
*The* Alt.Sources.Mac Archivist

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

>From [e-mail] (Andre Horstmann)
Subject: EventAvail alternatives wanted
Date: Wed, 08 May 1996 21:28:19 +0200
Organization: University of Fribourg, Switzerland


I need fast alternatives to the toolcall EventAvail. Up to now I used the
(documented) global variable EventQueue (0x014A) to see whether the queue
is empty (which then means: no events available).

Unfortunately an empty queue does not hold information about the mouse
position and the modifiers, as EventAvail would do! Is there any way (e.g.
global variables) to check for these.

Thanks for your help.

Andre

--
mailto:[e-mail] - http://www.swix.ch/clan/shadow/ (11.4.96)

The worst about computers: they never admit being responsible for an error.

              *** Fast Eddie Laboratories, Switzerland ***

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

>From [e-mail] (Adam Winer)
Date: Wed, 08 May 1996 19:45:29 -0700
Organization: Oracle Corporation

In article <[e-mail]>,
[e-mail] (Andre Horstmann) wrote:

> I need fast alternatives to the toolcall EventAvail. Up to now I used the
> (documented) global variable EventQueue (0x014A) to see whether the queue
> is empty (which then means: no events available).
>
> Unfortunately an empty queue does not hold information about the mouse
> position and the modifiers, as EventAvail would do! Is there any way (e.g.
> global variables) to check for these.

OSEventAvail() is much faster than EventAvail() (it doesn't
give any time to background processes).  A simple call of
OSEventAvail(0, &event) should give you what you want.

-- Adam Winer
[e-mail]

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

>From [e-mail] (Steven Johnson)
Subject: Finding Apps In Desktop DB?
Date: Thu, 09 May 1996 14:43:45 -0500
Organization: Macromedia

If I have a file and and want to find the app(s) with the same creator,
it's pretty easy (just call PBDTGetAppl).

However, let's say I have a file with a bogus creator (e.g., ????) but a
good filetype (e.g., PICT), and I want to find all the apps that claim to
be able to open that filetype.

Is there any good way of doing this, sort of a brute-force disk search?

It appears that there isn't the inverse of PBDTGetAPPL, i.e.,
PBDTGetAppsThatCanOpenThisFileType().

Nor is there a PBDT call to index thru the applications (so that I could
then use other PBDT calls to see what filetypes they support).

There's obviously *some* way to get at this info, since both the Finder
and the  Translation Mgr do this. But I can't find it documented anywhere.


Anyone responding, I'd appreciate you e-mailing a copy as well as a public
posting. Thanks!

--
Steven Johnson               |
Senior Engineer              |  "Power lines have floaters
Macromedia                   |   so the airplanes won't get snagged."
[e-mail]      |

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

>From [e-mail] (Andrew Nemeth)
Date: 12 May 1996 20:49:50 GMT
Organization: Kralizec Dialup Unix

Steven Johnson ([e-mail]) wrote:
: If I have a file and and want to find the app(s) with the same creator,
: it's pretty easy (just call PBDTGetAppl).
:
: However, let's say I have a file with a bogus creator (e.g., ????) but a
: good filetype (e.g., PICT), and I want to find all the apps that claim to
: be able to open that filetype.

: Is there any good way of doing this, sort of a brute-force disk search?

Have a look at my 'AppLauncher' C++ code (especially the
'TLaunch' class) to see how I search both the desktop
database and the file catalogue for files.

The code is available from:
o  CW8 Reference CD
o  Celestin Apprentice IV CD
o  Info-mac dev/src
o  My WWW page

Andrew N.

Quicktime VR photography & services
C++ & Java programming
 http://www.zeta.org.au/~aznemeng/


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

>From [e-mail] (Jump Long)
Date: 12 May 1996 18:33:54 -0400
Organization: America Online, Inc. (1-800-827-6364)

Steven Johnson wrote:
>If I have a file and and want to find the app(s) with the same
>creator, it's pretty easy (just call PBDTGetAppl).
>  However, let's say I have a file with a bogus creator (e.g.,
>????) but a good filetype (e.g., PICT), and I want to find all
>the apps that claim to be able to open that filetype.
>
>Is there any good way of doing this, sort of a brute-force disk
>search?
>  It appears that there isn't the inverse of PBDTGetAPPL, i.e.,
>PBDTGetAppsThatCanOpenThisFileType().
>
>Nor is there a PBDT call to index thru the applications (so that
>I could then use other PBDT calls to see what filetypes they
>support).
>  There's obviously *some* way to get at this info, since both
>the Finder and the  Translation Mgr do this. But I can't find it
>documented anywhere.
>
>
>Anyone responding, I'd appreciate you e-mailing a copy as well
>as a public posting. Thanks!

I've never messed with the Translation Manager, but I have worked with
Desktop Manager and File Manager a lot, so I figured I'd give this a
crack.

It looks like the Translation Manager gives you a way to find out what
file types a specified application can open - the
GetFileTypesThatAppCanNdoesn't seem to be the inverse of that call - a
function that given a target file, returns a list of applications that say
they can open that file. If you're just wanting to open a specific file,
the easiest thing to do would be to tell the Finder to open the file with
an Apple Event. If the file's creator application isn't available and the
Translation Manager is available, the user will be presented the
"translation choices" dialog box where they can pick another application
that says it can open that file type.

However, if you really want to build the list yourself, I just wrote the
code to build a list of applications that say they can open the target
file. I've pasted the code for "GetAppsThatCanOpenDocNatively" into the
next message. GetAppsThatCanOpenDocNatively isn't really fast because it
calls GetFileTypesThatAppCanNativelyOpen once for each application
('APPL') it finds on all volumes.

By the way, the code uses a routine from MoreFiles. If you don't have
MoreFiles, here's its URL:
<ftp://members.aol.com/JumpLong/MoreFiles_1.4.2.sea.hqx> If you find a bug
in GetAppsThatCanOpenDocNatively, let me know so I can correct my copy of
it.

- Jim Luther

[e-mail]
<http://members.aol.com/JumpLong/>


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

>From [e-mail] (Jump Long)
Date: 12 May 1996 18:33:57 -0400
Organization: America Online, Inc. (1-800-827-6364)

Here's the code for GetAppsThatCanOpenDocNatively.

- Jim Luther

[e-mail]
<http://members.aol.com/JumpLong/>

- --------

#include <Files.h>
#include <Translation.h>
#include "MoreFilesExtras.h"

/* handle to array of FSSpecs */
typedef FSSpecHandle FSSpecArrayHandle;

pascal OSErr GetAppsThatCanOpenDocNatively(const FSSpec *targetDocument,
FSSpecArrayHandle *appList, unsigned long *count)
{
 enum
 {
  kIgnoreCreator = 0x00000000,
  kAPPLFileType = 'APPL',
  kMaxSpecs  = 10
 };

 OSErr result, memMgrErr;
 FInfo fndrInfo;
 OSType targetFileType;  /* file type of the target file */
 HParamBlockRec pb;
 short volIndex;  /* for indexing through the list of mounted volumes */
 Boolean volDone;  /* flag that indicates when we should stop looking for
new volumes */
 FSSpec specs[kMaxSpecs]; /* an array for getting application FSSpecs */
 long actMatchCount;  /* number of valid FSSpecs in specs array */
 long appIndex;  /* for indexing through the list of applications on a
volume */
 Boolean newSearch;
 TypesBlock nativeTypes;  /* array of file types an application can open
*/
 short typeIndex;  /* for indexing through the list of file types an
application can open */

 /* No matches yet */
 *count = 0;

 /* Allocate handle for matches */
 *appList = (FSSpecHandle)NewHandle(0);
 if ( *appList != NULL )
 {
  /* What file type are we trying to open */
  result = FSpGetFInfo(targetDocument, &fndrInfo);
  if ( result == noErr )
  {
   targetFileType = fndrInfo.fdType;

   /* Index through the mounted volumes */
   pb.volumeParam.ioNamePtr = NULL;
   volIndex = 1;
   volDone = false;
   while ( !volDone )
   {
    pb.volumeParam.ioVolIndex = volIndex;
    if ( PBHGetVInfoSync(&pb) == noErr )
    {
     memMgrErr = noErr;
     newSearch = true;
     do
     {
      /* Find applications on this volume */
      result = CreatorTypeFileSearch(NULL, pb.volumeParam.ioVRefNum,
                kIgnoreCreator, kAPPLFileType,
                specs, kMaxSpecs, &actMatchCount, newSearch);
      if ( (result == noErr) || (result == eofErr) )
      {
       /* Look at each application found */
       for ( appIndex = 0; appIndex < actMatchCount; ++appIndex )
       {
        /* Get this application's creator type */
        if ( FSpGetFInfo(&(specs[appIndex]), &fndrInfo) == noErr )
        {
         /* Ask the Translation Manager what file types this application
can open */
         if ( GetFileTypesThatAppCanNativelyOpen(pb.volumeParam.ioVRefNum,
           fndrInfo.fdCreator, (FileType *)&nativeTypes) == noErr )
         {
          /* Look through the FileTypes returned for the target's file
type */
          typeIndex = 0;
          while ( nativeTypes[typeIndex] != 0 )
          {
           if ( nativeTypes[typeIndex] == targetFileType )
           {
            /* Add this application's spec to the list */
            memMgrErr = PtrAndHand(&(specs[appIndex]), (Handle)*appList,
sizeof(FSSpec));
            ++(*count); /* Increment match count */
            break; /* while ( *nativeTypePtr != 0 ) */
           }
           ++typeIndex; /* next file type */
          }
         }
        }
       }
       newSearch = false; /* it's not a new search anymore */
      }
     } while ( (result == noErr) && (memMgrErr == noErr) );

     /* If there was a memory Manager error, bail out now */
     if ( memMgrErr == noErr )
     {
      if ( result == eofErr ) /* eofErr is OK */
      {
       result = noErr;
      }
     }
     else
     {
      result = memMgrErr;
      volDone = true;
     }

     ++volIndex; /* next volume */
    }
    else
    {
     volDone = true;
    }
   }
  }

  /* Dispose of handle if errors or if no matches */
  if ( (result != noErr) || (*count == 0) )
  {
   DisposeHandle((Handle)*appList);
   *appList = NULL;
   *count = 0;
  }
 }
 else
 {
  result = memFullErr;
 }
 return ( result );
}

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

>From [e-mail] (Marshall Vale) (Marshall Vale)
Subject: Finding the caller of a CFM sharedlib?
Date: Thu, 09 May 1996 10:58:03 -0400
Organization: Massachusetts Institute of Technology

Hi,

 Is there a way to find out who the caller of a CFM shared library is? From
reading through IM and a few other sources, there doesn't seem to be a
good public way of doing. The purpose of this is to be able to do some
tracking on a product that we don't have the source to, we're writing the
dll. If the solution isn't clean, that's ok.

TIA,
Marshall

Marshall Vale |   [e-mail]  | "Das Schicksal des Mannes ist knusprig
MacDevGuy, IS | Massachusetts Institute of Technology |    und lecker."

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

>From Robert van Uitert <[e-mail]>
Subject: If you don't want to *wait* for events...
Date: 18 May 1996 00:29:37 GMT
Organization: Three-Space Interactive

/*
Hi everyone,

There seems to be some confusion about the slowness of getting events,
the overhead of the Mac OS, having to quit the Finder for better
performance, etc. I hope I can clear up some things.

Below you will find the C++ code for a little program that tests the
speed of the various event-retrieval methods (WaitNextEvent, etc.).
Just compile and run it. You may learn something! I did! ;-)

Before you compile it, you should set the kCyclesPerSec constant (in
the first line of code) to your machine's clock speed.

After running this program, you should note the following:
- WaitNextEvent, GetNextEvent and EventAvail are faster when there's
an updateEvt pending. I assume background apps are not given any time
until the front app has handled all update events.
- GetOSEvent is a *lot* faster than WNE/GNE. It's very uncooperative
by not giving any time to background processes, but that's just fine
for a game that takes over the screen/system. If low-level events
(i.e. all events other than update, activate, suspend/resume, mouse-
moved and high-level events) are all you need, then use GetOSEvent and
do *not* use WNE/GNE.
- GetOSEvent is slower (on my 6100/66 at least) than GetKeys, but if
you also need the state of the mouse button, GetOSEvent is faster than
GetKeys and Button combined.

The fastest way of processing low-level events is to first check
whether there's one available by looking at the qHead (or qTail) field
of the event queue header (which you can get from GetEvQHdr,
GetEventQueue or LMGetEventQueue), and then (if necessary) call either
GetOSEvent or the low-level Dequeue function, as follows:

    if ((elem = (EvQElPtr)queue->qHead) != nil) {
        switch (elem->evtQWhat) {
        ...
        }
        Dequeue((QElemPtr)elem, queue);
    }

The Dequeue function apparently also adds new events to the queue.
This is pretty much undocumented, however, and for the sake of
compatibility I wouldn't use this method in any commercial product.
The following works just as well (or better):

    if (queue->qHead) {
        GetOSEvent(everyEvent, &event);
        switch (event.what) {
        ...
        }
    }

Of course, the above won't do the job if you want null events too
(e.g. to read the up-to-date state of the modifier keys); in that
case, just call GetOSEvent without testing queue->qHead.

Happy happy, joy joy,

De ballen,

Robt.
*/


#define kCyclesPerSec 66000000 // For a 66 MHz CPU
#define reg register
#define Ticks (*(long *)0x16A)

static long lengthOfCStr(reg char *s)
{
    reg char *p = s - 1;
    while (*++p)
        ;
    return p - s;
}

void main()
{
#define TEST(code)\
    n = 0;\
    t = Ticks + 60;\
    do {\
        code\
        ++n;\
    } while (Ticks < t);\
    \
    MoveTo(50, qd.thePort->pnLoc.v + 20);\
    DrawText(#code, 0, lengthOfCStr(#code));\
    MoveTo(400, qd.thePort->pnLoc.v);\
    NumToString(n, s);\
    DrawString(s);\
    MoveTo(500, qd.thePort->pnLoc.v);\
    NumToString(kCyclesPerSec / n, s);\
    DrawString(s);

    MaxApplZone();
    InitGraf(&qd.thePort);
    InitFonts();
    InitWindows();

    SetPort(NewWindow(nil, &qd.screenBits.bounds, "\p", true,
            dBoxProc, (WindowPtr)-1, false, 0));
    TextFont(monaco);

    EventRecord event;
    KeyMap keyMap;
    Str255 s;
    reg long n, t;
    reg QHdrPtr queue = GetEventQueue();

    for (n = 0; n < 10; ++n)
        WaitNextEvent(everyEvent, &event, 1, nil);

    MoveTo(365, 40);
    DrawString("\piterations/sec");
    MoveTo(500, 40);
    DrawString("\pcycles/iteration");

    MoveTo(50, 70);
    DrawString("\pWith a pending updateEvt:");
    TEST(  WaitNextEvent(everyEvent, &event, 0, nil);  )
    TEST(  GetNextEvent(everyEvent, &event);  )
    TEST(  EventAvail(everyEvent, &event);  )

    for (n = 0; n < 10; ++n) {
        WaitNextEvent(everyEvent, &event, 1, nil);
        if (event.what == updateEvt) {
            BeginUpdate((WindowPtr)event.message);
            EndUpdate((WindowPtr)event.message);
        }
    }
    MoveTo(50, qd.thePort->pnLoc.v + 30);
    DrawString("\pAfter the updateEvt is handled:");
    TEST(  WaitNextEvent(everyEvent, &event, 0, nil);  )
    TEST(  GetNextEvent(everyEvent, &event);  )
    TEST(  EventAvail(everyEvent, &event);  )

    Move(0, 10);
    TEST(  GetOSEvent(everyEvent, &event);  )
    TEST(  OSEventAvail(everyEvent, &event);  )
    TEST(  if (queue->qHead) GetOSEvent(everyEvent, &event);  )

    Move(0, 10);
    TEST(  GetKeys(keyMap);  )
    TEST(  Button();  )

    MoveTo(50, qd.thePort->pnLoc.v + 30);
    DrawString("\pTimer overhead:");
    TEST(  ;  )

    MoveTo(50, qd.thePort->pnLoc.v + 40);
    DrawString("\pPress the mouse button to quit");
    while (!Button())
        ;
    FlushEvents(everyEvent, 0);
}

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

>From Andrew Edward White <andreww>
Date: 20 May 1996 03:03:08 GMT
Organization: School of CompSci & Eng, Uni Of NSW, Oz

In article <[e-mail]> Robert van Uitert <[e-mail]> writes:
>
>After running this program, you should note the following:
>- WaitNextEvent, GetNextEvent and EventAvail are faster when there's
>an updateEvt pending. I assume background apps are not given any time
>until the front app has handled all update events.

Yes.  Not handling update events is a great way to lock up your
communications software (or other time critical background processes).

--
Andrew White
[e-mail]
http://www.cse.unsw.edu.au/~andreww/
"A complex problem is merely a simple hierarchy of simple problems"

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

>From [e-mail] (Peter A. Dinda)
Subject: MacFS: A Portable Macintosh Filesystem
Date: Thu, 09 May 1996 14:41:12 GMT
Organization: Carnegie Mellon University SCS


MacFS: A Portable Macintosh Filesystem

Copyright (c) 1996 by Peter A. Dinda, George C. Necula, and Morgan Price

Many moons ago, George C. Necula, Morgan Price, and I built a Macintosh
Heirachical File System implementation with an eye towards portability.  For a
variety of reasons, mostly time constraints and because none of our respective
research areas encompasses filesystem design and implementation, MacFS has been
sitting on a shelf until now.  We have decided to dust it off and make it
available to the net.  We hope that some young hackers with more time on their
hands than we have will port it to Linux, FreeBSD, NetBSD, OS/2, NT, etc.

MacFS is a complete (read/write) filesystem library which can be used to build
user-level and kernel-level support for Macintosh volumes.  Included in the
distribution are user-level utilities (ls/cp/etc), as well as a very alpha Mach
vfs (ie, vnode) built on top of the library.  The code has been tested on
PMAX/Mach 3.0 machines and Intel/NetBSD machines.

The source code for MacFS 0.1 and a technical report describing MacFS are
available via the "Programs" icon on the web page:

   http://www.cs.cmu.edu/afs/cs.cmu.edu/usr/pdinda/html/pdinda.html

The source code is also available by ftp via:

                ftp://ftp.cs.cmu.edu/user/pdinda/

Please read the (very liberal) license agreement available in each of these
locations.  Let us know if this code is useful to you.  Included below is the
abstract for the tech report:


We have created a Macintosh file system library which is portable to a
variety of operating systems and platforms.  It presents a programming
interface sufficient for creating a user level API as well as file
system drivers for operating systems that support them.  We
implemented and tested such a user level API and utility programs
based on it as well as an experimental Unix Virtual File System.

We describe the Macintosh Hierarchical File System and our
implementation and note that the design is not well suited to
reentrancy and that its complex data structures can lead to slow
implementations in multiprogrammed environments.  Performance
measurements show that our implementation is faster than the native
Macintosh implementation at creating, deleting, reading and writing
files with small request sizes, but slower than the Berkeley Fast File
System (FFS.)  However, the native Macintosh implementation can
perform large read and write operations faster that either our
implementation or FFS.



Peter August Dinda                                     [e-mail]
Doctoral Student, School of Computer Science, Carnegie Mellon University
   http://www.cs.cmu.edu/afs/cs.cmu.edu/usr/pdinda/html/pdinda.html

Peter August Dinda                                     [e-mail]
Doctoral Student, School of Computer Science, Carnegie Mellon University
   http://www.cs.cmu.edu/afs/cs.cmu.edu/usr/pdinda/html/pdinda.html


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

>From [e-mail] (Philippe Lang)
Subject: Serial port in use?
Date: Thu, 02 May 1996 16:12:39 +0200
Organization: EPFL

How can I know if a serial port is already in use, before opening it? I
thought this would be an easy job, but I haven't succeeded. The piece of
code I found in the developer CD does not work, and the device manager
OpenDriver routine does not return "portInUse".

I'm using system software 7.5.3.

Thanks

--
Philippe Lang
SWITZERLAND

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

>From [e-mail] (Steve Bower)
Date: 3 May 1996 23:56:53 GMT
Organization: Teleport - Portland's Public Access [phone]

"portInUse" is a low-level (in PRAM) state flag that tells the OS when
certain kinds of drivers are active and may be using the serial hardware
ports.  E.G. AppleTalk, Serial, or None.  Is this really the information
you want?  Or are you trying to use the serial driver and want know if
another application is already using it?

If the latter, the short answer is -- you can't find out unless you are
using the Communications Toolbox.  Apple didn't provide any mechanism for
arbitrating hardware ports when they designed the Mac OS.  The CTB was an
attempt to rectify that problem -- with mixed results.

-Steve


In article <[e-mail]>,
[e-mail] (Philippe Lang) wrote:

> How can I know if a serial port is already in use, before opening it? I
> thought this would be an easy job, but I haven't succeeded. The piece of
> code I found in the developer CD does not work, and the device manager
> OpenDriver routine does not return "portInUse".
>
> I'm using system software 7.5.3.
>
> Thanks
>
> --
> Philippe Lang
> SWITZERLAND

--
-Steve                                         [e-mail]

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

>From [e-mail] (Philippe Lang)
Date: Sun, 05 May 1996 22:17:42 +0200
Organization: EPFL

In article <[e-mail]>,
[e-mail] (Steve Bower) wrote:

> "portInUse" is a low-level (in PRAM) state flag that tells the OS when
> certain kinds of drivers are active and may be using the serial hardware
> ports.  E.G. AppleTalk, Serial, or None.  Is this really the information
> you want?  Or are you trying to use the serial driver and want know if
> another application is already using it?
>
> If the latter, the short answer is -- you can't find out unless you are
> using the Communications Toolbox.  Apple didn't provide any mechanism for
> arbitrating hardware ports when they designed the Mac OS.  The CTB was an
> attempt to rectify that problem -- with mixed results.

Thanks Steve,

Yes, I want to know if another application is already using a serial
port... There is really no solution? Gosh. Is it possible to know the
state of a serial port with the help of the Comm Toolbox, even if I'm not
using the Comm Toolbox for sending data? I suppose no...

--
Philippe Lang
SWITZERLAND

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

>From [e-mail] (Christopher Swan)
Date: Thu, 09 May 1996 20:45:20 +1200
Organization: Raine Storm Softworks

>Yes, I want to know if another application is already using a serial
>port... There is really no solution? Gosh. Is it possible to know the
>state of a serial port with the help of the Comm Toolbox, even if I'm not
>using the Comm Toolbox for sending data? I suppose no...

In theory you can use the 'serial port arbitrator' that comes with ARA -
but its never worked for me. The CTB does not really arbitrate serial
ports (contrary to popular belief - although it does provide a
'IsDriverOpen' function) so the best solution is to 'walk' the driver
entry table and find the driver you want to open and see if it is already
open.

--

Cheers, Chris

- ---------------------------------------------------------------------
Christopher Swan                                 CompuServe 100354,3427
PO Box 11567, Wellington, New Zealand                 or [e-mail]
- ---------------------------------------------------------------------

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

>From [e-mail] (Harun Scheutzow)
Date: Thu, 9 May 1996 08:29:58 GMT
Organization: Village Tronic Marketing GmbH

You may look into the UTable and find the DCE (Device Control Entry).
In the DCE there you find the information whether the driver is opened
or closed. See IM Devices. Not very clean, but a possible solution for
your problem.

Regards, HS
<Opinions are my own>


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

>From [e-mail] (Sak Wathanasin)
Date: Thu, 9 May 1996 21:37:53 GMT
Organization: Network Analysis Ltd

In article <[e-mail]>,
[e-mail] (Philippe Lang) wrote:

> How can I know if a serial port is already in use, before opening it? I
> thought this would be an easy job, but I haven't succeeded. The piece of
> code I found in the developer CD does not work, and the device manager
> OpenDriver routine does not return "portInUse".

It does if you have ARA installed. If it isn't, you are supposed to walk
the device unit table, find the driver entry and

"look at bit 5 of the low-order byte of the dCtlFlags field of the Serial
Driver’s DCE"

according to tech note DV555 - Serial driver Q & A. The ARA API manual says

"When installed Remote Access provides serial port arbitration throught
[sic!] the Serial Port Arbitrator tool.   All serial drivers registered
with the Communications Resource Manager are arbitrated by the Serial Port
Arbitrator.

To check to see if the Serial Port Arbitrator is installed, check the
gestaltSerialArbitrationExists flag of the gestaltArbitorAttr Gestalt
selector  (see "Gestalts" section for these defines and an example of this
call).

If serial port arbitration is present, call OpenDriver when you want to
use a serial port.  If the driver requested is not open, OpenDriver will
return a result of noErr and the reference number of the driver.  If the
driver requested is open (in use), OpenDriver will return the error
portInUse.  When you are finished using the driver, call CloseDriver.
OpenDriver and CloseDriver calls should always be balanced,  although the
Serial Port Arbitrator will protect against multiple open/close calls.

If serial port arbitration is not present, do not use OpenDriver to
determine if the driver is open.  It will return you a result of noErr and
the reference number, allowing you access to a driver that another
application is using.   To determine if the serial driver requested is
open by another application, you must walk the DCE (Device Control Entry)
unit table (see Device Driver chapter of Inside Macintosh vol II)."

The ARA API guide has sample code on how to do this (with or without ARA
present), but I'm not sure if one is allowed to post it here (it's Apple's
copyright, so I'll leave it to someone from Apple to post it). The ARA SDK
is on the MacOS SDK CD which you can get from APDA.

--
Sak Wathanasin
Network Analysis Limited
178 Wainbody Ave South, Coventry CV3 6BX, UK

Internet: [e-mail]
uucp:     ...!britain.eu.net!nan!sw
Phone: [phone]                              Fax: [phone]

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

>From [e-mail] (Graham)
Subject: Tiny Object Framework anyone?
Date: Thu, 16 May 1996 17:00:05 GMT
Organization: (none)


I have written a tiny object framework for writing mac app's in C++
using CodeWarrior 8.0, mainly to teach my girlfriend OOP programming
with a gentler learning curve than, say PowerPlant. You can knock up
mac apps in minutes with it. (Four basic classes, plus one or two
others).

If anyone thinks this would be of use to them, I will release it as
freeware, if the demand exists, so eMail me back, or simply repost your
response.

I would post it immedsiately, but all in it runs to about a meg of
sources, etc., so I will spare the bandwidth for now.

--Graham.


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

>From [e-mail] (Mike Crawford)
Subject: Web page for Macsbug tips
Date: 7 May 1996 21:46:25 GMT
Organization: UC Santa Cruz - SCIPP

I am working on a Web page for Macsbug tips and tricks.  It's been
around for a while with not much content.  It still doesn't say
much, but it does now answer the two most frequent questions I
get from its readers:

Where do I get Macsbug?

Are there books about Macsbug?

I brought this up a while back and many of you sent me your
tricks and tips.  I filed them away until I could get around to
adding them.  If you have a tip you'd like to submit to the
page, or if you have a Macsbug or debugging web page that you'd
like me to link to, please mail me at [e-mail]

To visit the page, see:

http://www.scruznet.com/~crawford/Computers/macsbug.html

Best,
--
Mike Crawford                      | Free Mac source code.  The Word Services
[e-mail]              | allows you to link to a speller or other
[e-mail]          | text service.  See the W.S. home page at:
http://www.scruznet.com/~crawford/WordServices/wdsvindex.html


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

>From "Jim Cavera" <[e-mail]>
Subject: [SOURCE] MicroMovie (was: HELP! with QuickTime)
Date: 6 May 96 13:57:33 -0500
Organization: Purdue University

Due to overwhelming demand, I'm posting the source to a tiny QuickTime
app on my ftp-site.  MicroMovie reads a series of PICTs from its resource
fork and makes them into a QuickTime movie.  It's small.  It's simple.
It's easily adaptable to other stuff (animation, converting PICS files,
etc.).
It's pretty well commented.  It's not very pretty and it may be a bit
buggy (geez, whad' you exepect?  It took me all of a half hour).  You
can find it at :

ftp://ibcrc5.bio.purdue.edu/FTP/Public/MicroMovie68K.sit.hqx

If you have any problems getting it, feel free to drop me an e-line
and I'll try to mail you a copy.

Jim Cavera (bit-pushing slave)
[e-mail]

P.S.:  All of the MicroMovie stuff is in the public domain.  If,
however, you use it as the basis of a killer app and make a zillion
dollars off it, I would appriciate some recognition ;-)

P.P.S.:  Also, you may want to check out the Tools Plus 3.0 eval
kit at the same site.  If you program a lot and have stupid people
given rediculous deadlines, it will REALLY make your life
easier.


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

End of C.S.M.P. Digest
**********************