Hi,
How can we write a function, which functionality is similar to sizeof
function
any one send me source code
Reddy
90  8432  pn*********@gma il.com said: Hi,
How can we write a function, which functionality is similar to sizeof
function
We can't, because sizeof is not a function. (And there's a good reason why
it's not a function.)
--
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)
Richard Heathfield wrote: pn*********@gma il.com said:
Hi,
How can we write a function, which functionality is similar to sizeof
function
We can't, because sizeof is not a function. (And there's a good reason why
it's not a function.
Can you tell us that reason, Richard?
Regards,
Madhav.
Madhav said: Richard Heathfield wrote: pn*********@gma il.com said:
> Hi,
> How can we write a function, which functionality is similar to sizeof
> function
We can't, because sizeof is not a function. (And there's a good reason
why it's not a function.
Can you tell us that reason, Richard?
Spend a little time trying to write such a function, and you'll discover it
for yourself quickly enough. Hint: what type should its parameter be?
--
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) pn*********@gma il.com wrote: Hi,
How can we write a function, which functionality is similar to sizeof
function
any one send me source code
the problem is that the result of sizeof() is interpolated at compile
time. Can any function do it that way! :-)
Xicheng
"Xicheng Jia" <xi*****@gmail. com> wrote in message pn*********@gma il.com wrote: Hi,
How can we write a function, which functionality is similar to sizeof
function
any one send me source code
the problem is that the result of sizeof() is interpolated at compile
time. Can any function do it that way! :-)
A compiler is permitted to inline functions, and then to simplify code. A
really good compiler might simplify constructs like acos(0) to produce half
PI, but this is rare.
--
Buy my book 12 Common Atheist Arguments (refuted)
$1.25 download or $7.20 paper, available www.lulu.com/bgy1mm
Xicheng Jia posted: Can any function do it that way! :-)
A macro function perhaps:
#define SizeOf(Type) \
( \
(const char*)128 - \
\
(const char*)( (const Type*)128 - 1 ) \
)
--
Frederick Gotham
Richard Heathfield wrote: Spend a little time trying to write such a function, and you'll discover it
for yourself quickly enough. Hint: what type should its parameter be?
I think it is because we need C language to tell us the sizes of
various types and objects by sizeof. It's the purpose of sizeof itself
and why it is called the name operator. We have no alternative choice.
lovecreatesbeau ty
Frederick Gotham schrieb: Xicheng Jia posted:
Can any function do it that way! :-)
A macro function perhaps:
#define SizeOf(Type) \
( \
(const char*)128 - \
\
(const char*)( (const Type*)128 - 1 ) \
)
Undefined behaviour - your pointer most likely does not point to any
valid object. And even if it does on certain implementations , it makes
no sense in c.l.c as conversion from integer to pointer types is
implementation defined and thus not portable.
--
Marc Thrun http://www.tekwarrior.de/
Marc Thrun posted: Frederick Gotham schrieb: Xicheng Jia posted:
Can any function do it that way! :-)
A macro function perhaps:
#define SizeOf(Type) \
( \
(const char*)128 - \
\
(const char*)( (const Type*)128 - 1 ) \
)
Undefined behaviour - your pointer most likely does not point to any
valid object. And even if it does on certain implementations , it makes
no sense in c.l.c as conversion from integer to pointer types is
implementation defined and thus not portable.
Yes I'm aware of that.
This thread isn't about anything serious; it's more of a little mind game
to see who can write a "sizeof".
--
Frederick Gotham This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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