[Python-Dev] Problem with the memory docs

Guido van Rossum guido@python.org
Fri, 05 Apr 2002 11:18:41 -0500

> Tim Peters <tim.one@comcast.net> writes:
> > [martin@v.loewis.de]
> > > That, OTOH, is not what Guido wants it to be. Guido wants Py_Malloc to
> > > return 0 *only* in case of failure; allocating 0 bytes should
> > > "normally" succeed. I still cannot see what problems you have with
> > > this requirement.
> > 
> > I'm not following this at all.  Calling malloc(1) does exactly what Guido
> > wants.  "malloc(1)" isn't a broken Unix manpage reference, if that's how
> > you're reading it; it means call malloc with an argument of 1.
> I think I'm now getting to the root of your confusion. Calling
> malloc(1) is *not* what Guido wants. Instead, he wants that
> py_malloc(0) returns a non-null pointer "normally".
> Now, there are some C libraries which normally return a NULL pointer
> for malloc(0); as you point out, C gives them the freedom to do so. To
> work-around this under-specification, one can call malloc(1) -
> standards mandate that this does attempt to allocate something. It may
> be possible to find different work-arounds, but this is the most
> straight-forward one.

I'm still confused.  What is the difference between calling malloc(1)
and returning a non-null pointer "normally" ?

--Guido van Rossum (home page: http://www.python.org/~guido/)