[Tfug] Need help with a C++ algorithm

[Stephen Hooper]

On 3/15/07, Jude Nelson <judecn at gmail.com> wrote:
> Thanks for all the replies!

Which you obviously didn't really think about, though I still would
have written you a C program simply because I enjoy doing so....

> You're sure glibc's allocator doesn't have a method for
> determining the size of an allocated block, given a pointer to it?  I would
> be very surprised if it didn't, because then how would free() work?
>

If you read my email above I just explained how free worked...  the
integer below the base pointer is the allocated size of the block...

To restate the blindingly obvious "C" code, free does something like
this: "pointer - sizeof(size_t)" to find how much data was allocated
by the malloc.

Brian then went on to explain (very coherently) that that only works
with dynamically allocated memory (read "malloc").