Re: OFF-TOPIC: if (blah) ... "Daniel A. Koepke" at "Aug 12, 99 00:48:41 am"

From: Martijn Schoemaker (mschoe@osp.nl)
Date: 08/12/99


Hi all,

> Which is why I speculate it's a memory overrun.  C does not do runtime
> bounds checking, therefore if you write more bytes to a memory address
> than is allocated, the extra bytes will end up being written into other
> memory.  This often doesn't cause a crash because the overrun ends up into
> memory that also belongs to the program (thus, no segmentation fault).
> This means that it's quite conceivable you could fudge a 'next' pointer in
> descriptor_data without directly touching it.

Well time to make my point again, dunno if the last one came through
or it was just simply ignored ;) I have had mayor memory faults in
my mud (that's C's biggest Havoc) and searched to find a way to be
able to check memory consistency. I bumped into the dmalloc library
which is available from www.letters.com. I used this sort of garbage
collector and memory reference counter. It actually has options to
fill freed memory with certain patterns so you can make out a memory
overlap has occured. I have tracked down several (stock but mostly
own) memory errors which I would normally not have found in my lifetime.

Give it a try,

Aragorn
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