Thanks Helen

You will notice that the code in nested in a try .. finally structure
so it would be freed regardless of the exit.

--- In IBObjects@yahoogroups.com, Helen Borrie <helebor@t...> wrote:
> At 02:37 PM 1/04/2003 +0000, you wrote:
> >Hi
> >
> >Not sure if this is my fault, but I dont think so.
> >
> >I have an application which runs for weeks without being shut down,
> >but eventually crashes. It uses a TIB_Cursor to poll a database for
> >new information with the following piece of code:
> >
> > WCursor := TIB_Cursor.Create(Self);
> > try
> > WCursor.IB_Connection := Conn;
> > WCursor.SQL.Text := 'SELECT * FROM FAXQ WHERE STATUS=0 FOR
> >UPDATE';
> > WCursor.APIFirst; // This line is causing the problem
> > if WCursor.Eof then begin
> > Log.Lines.Add('No faxes found ....');
> > Shape.Brush.Color := COLOR_INACTIVE;
> > Conn.Disconnect;
> > Exit;
> > end else begin
> > ....
> > // do some other stuff
> > ....
> > end;
> > finally
> > WCursor.Unprepare;
> > WCursor.Free;
> > Conn.Disconnect;
> > end;
> >
> >When I call APIFirst, resources are being allocated that are not
> >unallocated - I am using a program called MemProof to check this,
and
> >it reports that the API call (isc_dsql_prepare) is not freeing the
> >resources as required.
>
> >Is this a IBO issue or a gds32.dll issue, or
> >is there something I am not understanding.
> >
> >I have run the app with the APIFirst commented out and the
resources
> >are not affected at all.
>
> Och aye, if you don't call a First method on your ib_cursor, it's
never
> prepared and it never opens. So - not much resource use there.
>
> But, errrrrm, take a fresh look at this block of code:
>
> if WCursor.Eof then begin
> Log.Lines.Add('No faxes found ....');
> Shape.Brush.Color := COLOR_INACTIVE;
> Conn.Disconnect;
> Exit; <---- WCursor never gets destroyed !!!
> end else
>
> >Do I need to call WCursor.Prepare explicitly?
>
> It won't hurt; but you shouldn't need to.
>
> The Prepare call does use resources, which will stay in use until
Unprepare
> is called. You don't actually need to call Unprepare at all, since
you are
> immediately destroying the cursor object. You only ever need to
call it
> for objects that you are going to keep on ice for later
(occasional) use.
>
> cheers,
> Helen