unsigned long long

[Richard A. Huebner]

Is the unsigned long long primitive data type supported in ANSI
standard C?

I've tried using it a couple of times in standard C, but to no avail.
I'm using both MS VIsual C++ 6, as well as the gcc compiler that comes
with RedHat linux 9.

If not, what data type will yield the largest unsigned integer for me?

Thanks for your help,

Rich

[P.J. Plauger]

"Tom St Denis" <to********@iah u.ca> wrote in message
news:P1******** *********@news0 4.bloor.is.net. cable.rogers.co m...

"Joona I Palaste" <pa*****@cc.hel sinki.fi> wrote in message
news:bo******** **@oravannahka. helsinki.fi...

ANSI is old. I for one welcome our new ISO overlords.

I would think that the difference between the ANSI and ISO versions of
the C standard is entirely bureaucratic and has no effect on the
technical content.

Be that as it may "unsigned long long" is part of ISOC AFAIK.

The current ANSI standard for C is identical to the current ISO
standard for C, aka C99.

P.J. Plauger
Dinkumware, Ltd.
http://www.dinkumware.com

[Joe Wright]

Richard A. Huebner wrote:

Is the unsigned long long primitive data type supported in ANSI
standard C?

I've tried using it a couple of times in standard C, but to no avail.
I'm using both MS VIsual C++ 6, as well as the gcc compiler that comes
with RedHat linux 9.

If not, what data type will yield the largest unsigned integer for me?

Thanks for your help,

Rich

Try this.

/*
Sizes of various things in bits..
*/
#include <stdio.h>
#include <limits.h>

int main(void) {
unsigned int a, b, c;
unsigned long long x, y, z;

c = -1;
b = 1 << (sizeof(int)*CH AR_BIT-1);
a = ~b;

z = -1;
y = 1LL << (sizeof(long long)*CHAR_BIT-1);
x = ~y;

printf("Size of void = %2lu bits\n", sizeof(void) *
CHAR_BIT);
printf("Size of char = %2lu bits\n", sizeof(char) *
CHAR_BIT);
printf("Size of short = %2lu bits\n", sizeof(short) *
CHAR_BIT);
printf("Size of int = %2lu bits\n", sizeof(int) *
CHAR_BIT);
printf("Size of long = %2lu bits\n", sizeof(long) *
CHAR_BIT);
printf("Size of long long = %2lu bits\n", sizeof(long long) *
CHAR_BIT);
printf("Size of int * = %2lu bits\n", sizeof(int *) *
CHAR_BIT);
printf("Size of char * = %2lu bits\n", sizeof(char *) *
CHAR_BIT);
printf("Size of void * = %2lu bits\n", sizeof(void *) *
CHAR_BIT);
printf("Size of float = %2lu bits\n", sizeof(float) *
CHAR_BIT);
printf("Size of double = %2lu bits\n", sizeof(double) *
CHAR_BIT);
printf("Size of long double = %2lu bits\n", sizeof(long double) *
CHAR_BIT);
printf("Max int = %11d\n", a);
printf("Min int = %11d\n", b);
printf("Max unsigned int = %11u\n", c);
printf("Max long long = %20lld\n", x);
printf("Min long long = %20lld\n", y);
printf("Max unsigned long long = %20llu\n", z);
return 0;
}

--
Joe Wright http://www.jw-wright.com
"Everything should be made as simple as possible, but not simpler."
--- Albert Einstein ---

[Eric Sosman]

Joe Wright wrote:

Richard A. Huebner wrote:

Is the unsigned long long primitive data type supported in ANSI
standard C?

I've tried using it a couple of times in standard C, but to no avail.
I'm using both MS VIsual C++ 6, as well as the gcc compiler that comes
with RedHat linux 9.

If not, what data type will yield the largest unsigned integer for me?

Thanks for your help,

Rich

Try this.
[code snipped; see up-thread]

I tried it, and the compiler said:

"foo.c", line 12: warning: integer overflow detected: op "<<"
"foo.c", line 19: cannot take sizeof void
cc: acomp failed for foo.c

--
Er*********@sun .com

[Richard Heathfield]

Joe Wright wrote:

<snip>

printf("Size of char = %2lu bits\n", sizeof(char) *
CHAR_BIT);

Apart from Eric's comments, you may find it a good idea to cast the
expression sizeof(char) * CHAR_BIT to unsigned long before passing it to a
variadic function such as printf.

--
Richard Heathfield : bi****@eton.pow ernet.co.uk
"Usenet is a strange place." - Dennis M Ritchie, 29 July 1999.
C FAQ: http://www.eskimo.com/~scs/C-faq/top.html
K&R answers, C books, etc: http://users.powernet.co.uk/eton

[Joe Wright]

Eric Sosman wrote:

Joe Wright wrote:

Richard A. Huebner wrote:

Is the unsigned long long primitive data type supported in ANSI
standard C?

I've tried using it a couple of times in standard C, but to no avail.
I'm using both MS VIsual C++ 6, as well as the gcc compiler that comes
with RedHat linux 9.

If not, what data type will yield the largest unsigned integer for me?

Thanks for your help,

Rich

Try this.
[code snipped; see up-thread]

I tried it, and the compiler said:

"foo.c", line 12: warning: integer overflow detected: op "<<"
"foo.c", line 19: cannot take sizeof void
cc: acomp failed for foo.c

What was wrong? Should ..
y = 1LL << (sizeof(long long)*CHAR_BIT-1);
be
y = 1ULL << (sizeof(long long)*CHAR_BIT-1);
or something?
--
Joe Wright http://www.jw-wright.com
"Everything should be made as simple as possible, but not simpler."
--- Albert Einstein ---

[Joe Wright]

Richard Heathfield wrote:

Joe Wright wrote:

<snip>

printf("Size of char = %2lu bits\n", sizeof(char) *
CHAR_BIT);

Apart from Eric's comments, you may find it a good idea to cast the
expression sizeof(char) * CHAR_BIT to unsigned long before passing it to a
variadic function such as printf.

Hmm.. size_t is unsigned long on my system. But I guess we're not
supposed to know that.
--
Joe Wright http://www.jw-wright.com
"Everything should be made as simple as possible, but not simpler."
--- Albert Einstein ---

[Dan Pop]

In <bo**********@s parta.btinterne t.com> Richard Heathfield <do******@addre ss.co.uk.invali d> writes:

Joe Wright wrote:

<snip>

printf("Size of char = %2lu bits\n", sizeof(char) *
CHAR_BIT);

Apart from Eric's comments, you may find it a good idea to cast the
expression sizeof(char) * CHAR_BIT to unsigned long before passing it to a
variadic function such as printf.

Or, more generally, to the actual type expected by the respective
conversion description.

Unless you're using a conforming C99 implementation, there is no
conversion description that is guarantee to properly handle a size_t
value. Even worse, in the case of sizeof(type) * CHAR_BIT, the type
of the expression can be either size_t or int.

Dan
--
Dan Pop
DESY Zeuthen, RZ group
Email: Da*****@ifh.de

[Dan Pop]

In <3F***********@ earthlink.net> Joe Wright <jo********@ear thlink.net> writes:

Try this.

/*
Sizes of various things in bits..
*/
#include <stdio.h>
#include <limits.h>

int main(void) {
unsigned int a, b, c;
unsigned long long x, y, z;

c = -1;
b = 1 << (sizeof(int)*CH AR_BIT-1);
a = ~b;

z = -1;
y = 1LL << (sizeof(long long)*CHAR_BIT-1);
x = ~y;

printf("Size of void = %2lu bits\n", sizeof(void) *
CHAR_BIT);
printf("Size of char = %2lu bits\n", sizeof(char) *
CHAR_BIT);
printf("Size of short = %2lu bits\n", sizeof(short) *
CHAR_BIT);
printf("Size of int = %2lu bits\n", sizeof(int) *
CHAR_BIT);
printf("Size of long = %2lu bits\n", sizeof(long) *
CHAR_BIT);
printf("Size of long long = %2lu bits\n", sizeof(long long) *
CHAR_BIT);
printf("Size of int * = %2lu bits\n", sizeof(int *) *
CHAR_BIT);
printf("Size of char * = %2lu bits\n", sizeof(char *) *
CHAR_BIT);
printf("Size of void * = %2lu bits\n", sizeof(void *) *
CHAR_BIT);
printf("Size of float = %2lu bits\n", sizeof(float) *
CHAR_BIT);
printf("Size of double = %2lu bits\n", sizeof(double) *
CHAR_BIT);
printf("Size of long double = %2lu bits\n", sizeof(long double) *
CHAR_BIT);
printf("Max int = %11d\n", a);
printf("Min int = %11d\n", b);
printf("Max unsigned int = %11u\n", c);
printf("Max long long = %20lld\n", x);
printf("Min long long = %20lld\n", y);
printf("Max unsigned long long = %20llu\n", z);
return 0;
}

Try it yourself, with the compiler in conforming mode, this time!

Dan
--
Dan Pop
DESY Zeuthen, RZ group
Email: Da*****@ifh.de

[Dan Pop]

In <z4************ *****@news04.bl oor.is.net.cabl e.rogers.com> "Tom St Denis" <to********@iah u.ca> writes:

"Joona I Palaste" <pa*****@cc.hel sinki.fi> wrote in message
news:bo******* ***@oravannahka .helsinki.fi...

Tom St Denis <to********@iah u.ca> scribbled the following:

> "Joona I Palaste" <pa*****@cc.hel sinki.fi> wrote in message
> news:bo******** **@oravannahka. helsinki.fi...
>> > ANSI is old. I for one welcome our new ISO overlords.
>>
>> I would think that the difference between the ANSI and ISO versions of
>> the C standard is entirely bureaucratic and has no effect on the
>> technical content.

> Be that as it may "unsigned long long" is part of ISOC AFAIK.

ISO C99, Tom. Not ISO C90.

Tom assumes we're dealing with the latest not the oldest.

An excellent illustration of the point I've made in another thread.

Dan
--
Dan Pop
DESY Zeuthen, RZ group
Email: Da*****@ifh.de

[Dan Pop]

In <3F***********@ earthlink.net> Joe Wright <jo********@ear thlink.net> writes:

Richard Heathfield wrote:

Joe Wright wrote:

<snip>

> printf("Size of char = %2lu bits\n", sizeof(char) *
> CHAR_BIT);

Apart from Eric's comments, you may find it a good idea to cast the
expression sizeof(char) * CHAR_BIT to unsigned long before passing it to a
variadic function such as printf.

Hmm.. size_t is unsigned long on my system. But I guess we're not
supposed to know that.

Even if you know that, do you also know what is size_t on the systems of
the people trying to use your program?

Dan
--
Dan Pop
DESY Zeuthen, RZ group
Email: Da*****@ifh.de