G'Day David,
 
-=> Quoting David Nugent to Frank Adam <=-
 > What i would like to know now is, if the allocated size of the array
 > ptr points at can be determined in some way.

 DN> Not by any documented means. The RTL or at least the 
 DN> operating system almost certainly would need to track the 
 DN> existing size of allocated memory blocks in order to 
 DN> implement realloc(), but the C programmer has no direct 
 DN> access to that information. It is ultimately up to you to 
 DN> keep track of it yourself.
Yep, someone will just have to find that location/table or whatever :)
There must be a table somewhere holding a handle,address and bytes.
I went through the interrupt list and no banana, perhaps it's the RTL,
wonder if i can walk through and search the whole memory without crashing
should be able to..I think i'll try that. 
I've noticed that OS' like to use negative offsets here or there, perhaps 
it tacks a few bytes in front of each memory block.             
 
 > I'm in the process of putting all my library function neatly together,
 > and i would love to make some functions capable of determining whether a
 > reallocation is necessary or not, and not rely on the programmer taking
 > care of it.

 DN> Write a front-end to malloc() to do it for you. I often use such a
 DN> wrapper  since it helps in debugging as well - I've included a 
 DN> variation of it below. You can detect heap corruption 
 DN> (boundary overwrite), attempting to free pointers which 
 DN> were not allocated from the heap to begin with, blocks that 
 DN> have already been freed, and you can issue diagnostics on 
 DN> where the function was called from and so forth.

-- cut & paste to clipboard --

Thanks, this'll ruin a whole afternoon for me to work out :)
That imaginary memtable still bugs me though, if it's in there i want it.
                

  L8r Frank (fadam{at}ozemail.com.au).
                  
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