sizeof 'a' returns 4

[lnitsu]

Hello

I've got a simple question regarding sizeof operator.
why sizeof 'a' return 4?
(Note the argument is without parenthesis)

If anybody is so kind to answer ...
TIA

[Xicheng Jia]

ln****@yahoo.co m wrote:

Hello

I've got a simple question regarding sizeof operator.
why sizeof 'a' return 4?
(Note the argument is without parenthesis)

If anybody is so kind to answer ...

check out the following page, it's a FAQ problem: -)

http://www.c-faq.com/charstring/sizeofchar.html

Xicheng

[lnitsu]

Excellent, thank you very much.
Xicheng Jia wrote:

ln****@yahoo.co m wrote:

Hello

I've got a simple question regarding sizeof operator.
why sizeof 'a' return 4?
(Note the argument is without parenthesis)

If anybody is so kind to answer ...

check out the following page, it's a FAQ problem: -)

http://www.c-faq.com/charstring/sizeofchar.html

Xicheng

[Sidhu]

Check out in this FAQ page:
http://www.c-faq.com/charstring/sizeofchar.html
ln****@yahoo.co m wrote:

Hello

I've got a simple question regarding sizeof operator.
why sizeof 'a' return 4?
(Note the argument is without parenthesis)

If anybody is so kind to answer ...
TIA

[Richard Heathfield]

ln****@yahoo.co m said:

Hello

I've got a simple question regarding sizeof operator.
why sizeof 'a' return 4?
'a' is an int. The size of an int is implementation-dependent. I guess on
your system it's 4, yes?
(Note the argument is without parenthesis)

Good. No point splashing them everywhere for no reason.

--
Richard Heathfield
"Usenet is a strange place" - dmr 29/7/1999
http://www.cpax.org.uk
email: rjh at above domain (but drop the www, obviously)

[Frederick Gotham]

posted:

Hello

I've got a simple question regarding sizeof operator.
why sizeof 'a' return 4?
(Note the argument is without parenthesis)

If anybody is so kind to answer ...
TIA

typedef T double;
unsigned SizeOf( T const t )
{
const char * const current = (const char*)&t;

const char * const next = (const char*)(&t + 1);

return next - current;
}


--

Frederick Gotham

[Richard Heathfield]

Frederick Gotham said:

posted:

Hello

I've got a simple question regarding sizeof operator.
why sizeof 'a' return 4?
(Note the argument is without parenthesis)

If anybody is so kind to answer ...
TIA

typedef T double;

Syntax error.

--
Richard Heathfield
"Usenet is a strange place" - dmr 29/7/1999
http://www.cpax.org.uk
email: rjh at above domain (but drop the www, obviously)

[lovecreatesbeauty]

Richard Heathfield wrote:

ln****@yahoo.co m said:

why sizeof 'a' return 4?

'a' is an int. The size of an int is implementation-dependent. I guess on
your system it's 4, yes?

But you seemed a little hesitant? If it's implementation-dependent, the
following equations are always true. It is true after my test :)

char c = 'c';
sizeof c == 1; /*by definition :)*/
sizeof 'c' == 4;

(Note the argument is without parenthesis)

Good. No point splashing them everywhere for no reason.

A pair of parentheses is required when type names applied to sizeof
operator. Is it because parentheses occur around type names in type
conventions?

lovecreatesbeau ty

[Richard Heathfield]

lovecreatesbeau ty said:

Richard Heathfield wrote:

ln****@yahoo.co m said:

> why sizeof 'a' return 4? 'a' is an int. The size of an int is implementation-dependent. I guess on
your system it's 4, yes?

But you seemed a little hesitant?

Well, it might not be 4. It might simply be that you had a bug in your
program. Or maybe you /do/ have a bug in your program, but ints are still
four bytes wide on your system. Who knows? Insufficient information
available.
If it's implementation-dependent, the
following equations are always true.

....when using the version of your compiler that you are currently using,
with the same settings, on the same operating system on the same hardware,
yes.

> (Note the argument is without parenthesis)

Good. No point splashing them everywhere for no reason.

A pair of parentheses is required when type names applied to sizeof
operator.

I so rarely need to know that, because I almost never use sizeof to find the
size of a type. I'm far more interested in the size of an /object/.

--
Richard Heathfield
"Usenet is a strange place" - dmr 29/7/1999
http://www.cpax.org.uk
email: rjh at above domain (but drop the www, obviously)

[Frederick Gotham]

Richard Heathfield posted:

Frederick Gotham said:

posted:

Hello

I've got a simple question regarding sizeof operator.
why sizeof 'a' return 4?
(Note the argument is without parenthesis)

If anybody is so kind to answer ...
TIA

typedef T double;

Syntax error.

So as not to clutter the newsgroup, I would request in future that, if
you choose to scrutanise and correct my code, that you correct the error
rather than simply indicate that an error is present -- it will be of
benefit to us all.
typedef double T;
Another thing, and this is your own perogative of course, maybe you'd
like to be more "social" about how you offer your counsel? It's pretty
clear that my error was more a question of "getting things muddled up"
rather than having a deficit of proficiency. When I myself correct such
silly errors, I am usually more sociable about it -- even one little
comment:

You've got them the wrong way around, should be:
typedef double T;


--

Frederick Gotham