NULL pointer and zero value

[vp]

If I have a pointer char * p, is it correct to assign NULL to this
pointer by:

"memset( &p, 0, sizeof(p));" instead of "p = NULL;"

The reason I ask is I have an array of structure of N function
variables, for example,

typedef struct
{
int (* func1)();
int (* func2)();
void * (* func2)(int );
} ModuleFunctions ;

#define N 100
ModuleFunction garMF[N];

When initializing, instead of making a loop to assgin NULL to each
function member of struct ModuleFunction for each member of array, is
it correct to do something like

memset( garMF, 0, sizeof(ModuleFu nctions)*N );
Thanks for your help,

DT

[pete]

Peter Pichler wrote:

"pete" <pf*****@mindsp ring.com> wrote...

Peter Pichler wrote:

"pete" <pf*****@mindsp ring.com> wrote...
> Jack Klein wrote:
>
> What you said, could also be used to explain a preference for
> char *pointer = 0;
> over
> char *pointer = NULL;

Not quite.
Since a void* is implicitly converted to any type*, the two
examples are exactly equivalent regardless
of any of the two standard definitions of NULL.

Exactly quite.
ModuleFunction garMF[N] = {NULL};
and
ModuleFunction garMF[N] = {0};
are exactly equivalent regardless of any of the two standard
definitions of NULL.

Only if garMF[N] is a pointer.

garMF[0].func1, is a pointer, which is plain from the code
that you snipped, so how does "Only if" enter into it?

--
pete

[stau]

On Thu, 01 Jan 2004 16:19:17 +1100, Peter Nilsson wrote:

"stau" <st**@pretogal. pt> wrote in message
news:pa******** *************** *****@pretogal. pt...

On Wed, 31 Dec 2003 15:37:42 +1100, Peter Nilsson wrote:

> I think Jack prefers {0} because it's a more consistent (and well
> understood) paradigm in general.

No, he explained why,and it makes logic.

How is "{0} works in all cases..." significantly different to what I said?
It's more succinct and better phrased, I grant you, but I don't see how my
sentence runs contrary to it.

It's clear to all that Jack was generalizing.

struct some { int *a, *b, c } = {NULL}
Will work.

struct some2 { int a, *b, *c } = {NULL}
This may or may not work, depending on the definition of NULL (ie. if
it'just 0 (zero) it will work, if it's ((void *) 0) it'll not work.

So, I kind of agree that it's good idea to use 0 to initialize structs,
but of course, this was 1F/2*OT in this thread.
I personally like to use the explicit NULL when I'm using pointers.

Best regards,
Stau no Preto.