"Stefan Wuebbe" <stefan.wuebbe@[EMAIL PROTECTED]
> wrote:
>"Gene Wirchenko" <genew@[EMAIL PROTECTED]
> wrote in message
>news:ro01o35j7thi8fof5tanbfoo0e97nml8qt@[EMAIL PROTECTED]
>> Gene Wirchenko <genew@[EMAIL PROTECTED]
> wrote:
>>
>> [snip]
>>
>>> MY QUESTION: Am I relying on any potentially undefined behaviour
>>>to get what appear to be correct results?
>>
>> I thought I had things working just fine. Suddenly, I am getting
>> C*5 errors. I do not always get them, but I can not see what it is
>> that is causing the problem.
>
>You get them when the code runs that you posted?
Well, I have had to fit it into my structure, but effectively,
yes. I think that VFP begs to differ.
>> What do you do to track down C*5 errors? The normal debugging
>> approaches do not work when VFP itself goes south.
>
>Firstly I'd Set Resource Off, or delete foxuser.* respectively.
No luck. BTW, this also nailed my settings, and it took some
doing to find out all the details to get back to sane settings.
>Then I'd have a look at all involved tables and their CDX files.
They seem to be fine though I really do not know what to do to
check them. I opened the table and listed it with each of the tags in
effect. I saw nothing odd.
>Then "dangling references" (although your code snippets do not
>look like that).
I was *VERY* careful about that.
>Then if the C5 exceptions occur on one machine only or on
>any PC - if the former, I'd have a look at driver issues - graphics
>("Hardware Acceleration"), printers if any.
Sometimes, the code works, and sometimes, it does not. One point
that I have not mentioned previously. When the code fails, it fails
at the beginning of the browse. First, the browse grid appears, then
the contents do. I usually get some of the contents, then boom! I do
not recall a case where the browse has blown up after it has completed
its initial display.
I have not been able to figure out a pattern. In following your
suggestions, I finally did get an error indicating a statement in the
browse function method. (Previously, they have been for the browse
statement.) It turned out to be the SQL-select. That did not help.
I think that I have some sort of Heisenbug here. For example, I
tried set coverage, and it changed the behaviour of the program!
I can not see what could be wrong in my code, so I am guessing. I
have inserted a number of statements to make very sure that everything
is as it should be. Nothing helps so far.
I have a few more ideas, but I sure dislike programming by guess
and by golly.
Sincerely,
Gene Wirchenko
Computerese Irregular Verb Conjugation:
I have preferences.
You have biases.
He/She has prejudices.
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