Re: Need info about Ada tasks

["Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>]

On Sat, 27 Sep 2008 00:56:59 -0500, Randy Brukardt wrote:

> "Fionn Mac Cumhaill" <invisible@hiding.from.spam> wrote in message 
> news:6vlpd4tho80qpm9vduvhggdeg3np867cvc@4ax.com...
>> On Fri, 26 Sep 2008 06:21:54 -0400, Stephen Leake
>> <stephen_leake@stephe-leake.org> wrote:
>>
>>>Fionn Mac Cumhaill <invisible@hiding.from.spam> writes:
>>>
>>>> I am using the MingW Ada compiler and the GWindows packages on Windows
>>>> XP.
>>>>
>>>> I am writing a simple program which observes a table in SQL Server
>>>> 2000 and lists its rows to a visible screen display. I need a simple
>>>> task structure that can update the display periodically, with a
>>>> specified wait time between updates. I need to be able to abort the
>>>> display task at any time when the display is not being updated.
>>>
>>>Mixing tasking and GUI events can be problematic; only one thread
>>>can call GUI functions.
> 
> That's not quite true, in that it's possible to use a binding that allows 
> multi-task access. Claw was designed to do that (it ensures that Windows is 
> happy by decoupling the underlying calls from your tasks). We indeed have 
> several examples that do pretty much what you are trying to do here (having 
> multiple tasks writing at once to different windows).

An addition. It is not always possible to route all events through GUI
ones. For example, in our systems we have events at ms rate and faster. No
GUI could ever handle this. Our events change the system state
independently on rendering. Keyboard, mouse and other GUI events are
processed separately. This is the design OP asked for. It works quite well.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de