Path: utzoo!attcan!uunet!ncrlnk!ncrcae!hubcap!gatech!uflorida!mailrus!tut.cis.ohio-state.edu!rutgers!orstcs!jacobs.cs.orst.edu!borcelf
From: borcelf@jacobs.cs.orst.edu (Fernando Borcel)
Newsgroups: comp.sys.mac.programmer
Subject: Help With VBL Tasks
Keywords: VBL task; post itself; BOMB
Message-ID: <8343@orstcs.CS.ORST.EDU>
Date: 19 Jan 89 02:06:58 GMT
Sender: usenet@orstcs.CS.ORST.EDU
Reply-To: borcelf@jacobs.cs.orst.edu (Fernando Borcel)
Organization: Oregon State University - CS - Corvallis Oregon
Lines: 53


I Started messing around with VBL tasks just today, following my IM II direc-
tions.  Now, I wore this rather silly task, just to see what it does, and it
worked (oh, surprise!), but for just a few times, bombing bad afterwards.

Here's what I wrote:

 procedure myVbl;
  var
   VBLTask : QElemPtr;
 begin
  SetUpA5;

  FlashMenuBar(0);  {my "TASK"}

  new(VBLTask);
  VBLTask^ := myVBLTask^;
  if vInstall(VBLTask) <> NoErr then  {Enqueue for Next VBL task}
   exitToShell;

  RestoreA5;
 end;


{later in the code, something I call only ONCE}
...
...
  new(MyVBLTask);
  with MyVBLTask^.VBLQElem do
   begin
    qtype := ord(vtype);
    vbladdr := @myVBL;
    vblCount := 5;
    vblPhase := 0;
   end;

  new(VBLTask);  {I decided to use a copy of the task}
  VBLTask^ := MyVBLTask^;
  if vInstall(VBLTask) <> NoErr then
   exitToShell;



---

I tried many other combinations, but none of them worked any better...

	Thanks.

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