GPF - problem

[Peter Stephensen]

I'm doing a program with a lot of simpel graphics (MoveToEx, LineTo, TextOut ect.). It is too long to post here.
The program gives gpf's all the time. The strange thing is that if i remove randomely some of the MoveToEx, LineTo or TextOut - statements the program runs OK. Is this a clue to whats wrong?

Any help will be very much appriciated!

Regards
Peter

[Lance Edmonds]

Without being able to try or review your code, a definitive solution is unlikely to be offered, however, you can try a few generic suggestions to try to trace the problem, in addition to single stepping the code in the debugger (which halts when a GPF occurs):

1. Add #DEBUG ERROR ON

2. Add #REGISTER NONE to the sub/function where the drawing takes place

3. Make sure that you are passing structure addresses to MoveToEX() correctly.

4. Double check array bounds are not exceeded

5. Create a log file in the drawing sub/function, and add a line to the sub to write an entry into the file for each drawing line processed. This way you'll get a direct reference to the point where the GPF occurs, simply by reviewing how far the log file got.

6. Suspect that the problem is elsewhere in your code, but only comes to light when the MoveToEX/LineTo functions are called (ie, something else is overwriting the memory/variables used in the drawing code).

If these suggestions dont help you solve your problem, then as a last resort you can email the code to me at mailto:[email protected][email protected]</A> and I'll take a quick look for you. No promises of an instant fix, but you never know.


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Lance
PowerBASIC Support
mailto:[email protected][email protected]</A>