Windows Vista Business class issue

[BOB MECHLER]

One of our new employess has the Windows Vista Business class on his laptop and found that Vista said a problem arose in a program he was testing that has been working fine in Xp for several years.

I put the #DEBUG ERROR ON statement and the top of the program to see if it was a beyond subscript range error which I had a error trap for.

Without doing anything else, the program started working without incidence. If I took it out, it stopped working again.

The Vista message simply said that TLEDTINI.EXE had a problem and had to close. After I put in the #DEBUG ERROR ON directive, it works fine.

Have any of you encountered this?

Bob Mechler

[Michael Mattias]

Um, that's a programmer error, which ALL of us have encounted.

When compiled with With #DEBUG ERROR ON, statements which would cause an array bound violation or use a NULL pointer - either of which may generate a protection fault - are not executed.. instead, the statement is skipped and the system ERR variable is set to a value of nine (9).

With #DEBUG ERROR ON you suffer no GPFs, but your data are invalid: Pick your poison.


MCM

[BOB MECHLER]

Brain freeze!!

I didn't have error trapping in all the functions. My bad. PB 7 and XP did not catch this error.

Bob Mechler

[Kev Peel]

Strictly speaking: the OS does not catch all memory errors, only illegal access to memory areas (ie. an address not given to your app by Windows), so if you corrupt the stack (for example) the results may not even be noticed until the program ends. The same goes for local memory corruption, the corruption may never trigger a GPF but your program may just output wrong results or act erratically.