Valentina 2.0. -- What is your 3 DREAM features?

[Robert Brenstein]

>on 2/1/04 11:52 AM, Erich Geiersberger at erichg at mcmm.com wrote:
>
>>>>  - Callbacks for client timeouts on active cursors
>>>>  It would save a lot of error tracking if we could get a message
>>>  in that case.
>>>
>>>  Explain please
>>
>>  Let's say a client has created server side cursors. He leaves while a
>>  data selection is open. When he comes back he might want to try to
>>  access one of the records. Since meanwhile his session has been
>>  terminated by the server I need to track for the error on each and
>>  every single data access.
>>
>>  I think the server knows which client has requested cursors. When a
>>  client timeout occurs, it could send a message back to the client
>>  before it disconnects the him.
>>  The same could be done when the server is stopped.
>
>-----------------
>>  At least Director offers callback methods which could receive such 
>>a message.
>>
>>  It would simplify handling of this kind of events. I could display an
>>  alert to the user "You have been disconnected due to inactivity" and
>>  send him back to a login screen.
>
>I see what you mean!
>
>Igor, to implement this, you need add into C++ Client SDK,
>Callback function which IS called when server send to client message that it
>is disconnected.
>
>I am sure it send such message, yes?
>
>Then we will be able use this callback to implement in V4MD and V4RB
>callback on Lingo and RB code level. You see?
>REALbasic name this Events it seems.
>
>
>--
>Best regards,
>Ruslan Zasukhin      [ I feel the need...the need for speed ]


I am not sure whether supporting callbacks is the true solution. I 
think it covers really only the situation when the disconnection is 
due to inactivity or when the server administrator disconnects the 
user. If the disconnection is due to network, server, or client 
computer malfunction, the callback can't reach the client or be used 
as expected. So, error checking on the client side is required 
anyway. Basically, when using network, we can't assume uninterupted 
communication, so the programs on both ends have to account for it on 
each and every client-server exchange. But, of course, if 
implementing callbacks is not a big deal, it may be nice to have them 
to simplify things in some cases.

Robert