Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!rutgers!psuvax1!psuvm.bitnet!cunyvm!nyser!cmx!rodan.acs.syr.edu!pcossenb
From: pcossenb@rodan.acs.syr.edu (Paul C. Ossenbruggen)
Newsgroups: comp.sys.mac.programmer
Subject: Heaps + Undo
Message-ID: <1634@cmx.npac.syr.edu>
Date: 5 Jun 89 20:50:25 GMT
Sender: usenet@cmx.npac.syr.edu
Reply-To: pcossenb@rodan.acs.syr.edu
Organization: Syracuse University, Syracuse, New York
Lines: 30

I have a question about heaps. It seems that during the execution of my program
a lot of little handles are created (13 bytes, to be exact) and then deleted.
So what I get on the heap is hundreds of these thirteen byte chunks of free
space. It does not seem to create any problems but I am wondering if it is
symptomatic of a bug. I have used TMON's heap scramble and purge
and have had no crashes (this also gets rid of them). So if it does not matter,
I will forget about it but if you know what might be the cause and if it is a
problem please let me know.

Also does anyone have any experience writing routines to handle undo? If you
have, could you give me an overview of the procedures involved for implementing
it in a graphics environment? I'd mainly like to know how you store the info
that has been deleted and then restore it without creating anomolies. It would
be really helpful if you had some example code I could look at or if you know
of some that is available.

Thanks.
 - Paul








-------------------------------------------------------------------------------
|  Paul C. Ossenbruggen                     pcossenb@rodan.acs.syr.edu        |
|  Syracuse University                      rspco@suvm.bitnet                 |
|                                            pcossenb@sunrise.acs.syr.edu      |