Proposed addition of malloc_size_np()

[John Baldwin]

On Sunday 26 March 2006 13:04, Jason Evans wrote:
> Robert Watson wrote:
> > I wonder if the intuitive objection people are raising is actually with 
> > the name.  Since malloc_size() is defined on at least one platform to 
> > return the requested size, maybe a name like malloc_allocated_size() (or 
> > something a bit more compact) would help avoid that confusion, and make 
> > it clear that the consumer is getting back a commitment and not a hint 
> > for future realloc(), etc.
> 
> Maybe you're right.  We could just call it malloc_usable_size() and be 
> compatible with Linux.

It would help to know why such a function would be useful. :)  Do you have
a specific use-case?  If the purpose is for a program to see that it really
as Y >= X bytes when it did malloc(X) so that the program can use Y bytes,
that would seem to only be a source of bugs and complexity.  If the program
wants Y bytes, it should malloc(Y).  Many folks in the thread seem to think
that this function would be used for a poor-man's realloc() wrapper or
something, and I think such uses would be short-sighted at best.  If there
are other uses such as for having a debug malloc wrap the real one, then
that might justify the API, but it is unclear what a useful use of this API
would be.

-- 
John Baldwin <jhb at FreeBSD.org>  <><  http://www.FreeBSD.org/~jhb/
"Power Users Use the Power to Serve"  =  http://www.FreeBSD.org