Re: A92: Corrupted programs


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Re: A92: Corrupted programs




TurboSoft@aol.com writes:

> Do you know anything about a program being able to corrupt itself if it is 
> stored in RAM?  l am asking because many times when running Aerox, if stored 
> in RAM (not archived) then after being run a number of times the polygons 
> will sometimes get distorted, or extra shapes will appear or something.  This 
> can't be from the user because once it gets like this it will be corrupted 
> until it is sent again via link.  Also if the now-corrupted Aerox program is 
> sent to another calc the same thing will happen on it too.  l don't think 
> that it is in saving the numberical data; it seems like the 
> equations/algorithms that draw the polygons are somehow getting corrupted.  
> ls there a way to fix this?  Of course the program can be archived right 
> after it is sent to the calc, but then the data won't be saved in the 
> program.  Help!

yes, it is normal, everytime you modify a variable in an ASM program,
you modify the value forever.
Basically, if the program is badly written, it could very well have
some buffer overflows thus writing over some areas where it is not
supposed to write... Typically, here, your app could use a counter
which is stored in RAM...


This is due to the fact that we have no HD in the ti calcs.

The programs are stored in RAM directly which means that when they run
and when they access their variables, they don't do it on a copy of 
themselves (copied by the OS loader) but on themselves which has
both advantages and drawbacks...

You could add a feature in the OS to make copies of your program just before 
running it and then run the copy. However, this would of course diminish the
amount of free memory available during the running...


regards,
Mathieu



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