Re: obj function hello()

On Feb 9, 9:41 pm, Christopher Benson-Manica
<a...@xxxxxxxxxxxxxxxxxxx> wrote:
gert <gert.cuyk...@xxxxxxxxx> wrote:
I modified the example a bit to give it a more oo look but i still
having trouble understanding the memory allocation part ?
Obj* myobj = malloc(sizeof *myobj);
for me it would make more sense if i would wright
Obj* myobj = malloc(sizeof myobj);

Why? myobj is a *pointer* - you want enough memory for myobj to point
to an Obj, not however much memory the pointer takes up. This is a
crucial difference.

The thing is they both give the same output :)

Only because you seem to be lucky - the second version is wrong, and
either happens to allocate enough space for an Obj (implying
sizeof(Obj) < sizeof(Obj*)) or accesses memory it has no right to
access.


Ok i see, i have to allocate memory for myobj not the pointer it self


.

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