comp.lang.c Google Group

offsetof-style Fun with Ternary Conditional

2010-08-01T08:14:06Z

A possibly interesting/curious use of the ternary conditional
operator...
The only thing I could find to do with it was the non-portable:
(1 ? 0 : &(x))
((size_t)&(NULL_OF_TYPE(id)->m ember))
int main(void) {
struct {
double bar;
long baz;
} foo;
return (int)offsetof2(foo, baz);
This 'offsetof2' macro doesn't take 'struct XXX' as its first

Re: "claim", etc. (was Re: C Standard Regarding Null Pointer Dereferencing)

2010-08-01T00:31:45Z

Thank for your acknowledging that fluency in English is not sufficient
cause for awareness of the negative connotations you perceive. I
agree.
It's not an accusation. It's a claim that there is no supporting
reference to the text given. You can demonstrate otherwise. You can
choose to ignore (ie. "plonk"). Your knowledge that there _is_ text

Re: "claim", etc. (was Re: C Standard Regarding Null Pointer Dereferencing)

2010-08-01T00:08:24Z

By all means, that's a worthy cause. :)
I agree. I believe that people associating a claim of a claim with a
dispute for the latter claim will find their doubt-casting. That can
be reconditioned just as avoidance of "bad words" can be
reconditioned.
"Wordy and pedantic style" applies to _my_ posts _already_. :) It

Re: manipulate fd underlying stream

2010-07-31T23:11:45Z

Sorry.

Re: Proposal for Amendment to Section 6.5.3.2, Unary * Operator

2010-07-31T23:04:08Z

On Jul 31, 6:29 pm, Marcin Grzegorczyk <mgrze...@poczta.onet.pl>
wrote:
Thanks for the constructive feedback, Marcin!
I will have to look for this C1X draft. Is 'void' considered an
incomplete object type in C1X, do you know? I will try to find the
draft you've kindly referred to and find out, but if it's readily

Re: manipulate fd underlying stream

2010-07-31T22:59:48Z

that was a direct quote from MSDN, which I didn't make clear
perhaps I didn't make my point clearly enough. *Is* Linux a dominant
implementation? I think this is far from indiputable.

Re: Proposal for Amendment to Section 6.5.3.2, Unary * Operator

2010-07-31T22:29:03Z

Instead of "pointer type pointing to an incomplete type", you could just
say "pointer to an incomplete type". In addition, recently there has
been a consensus that completeness is a scoped property of a type
(see N1439), and the current C1X draft has adopted the change, so it
should really be "pointer to an incomplete object type".

Re: MIDI files in C(lccwin/WIN XP)

2010-07-31T22:26:43Z

going off-topic here...
this is really not a good group for this question (non-standard,
non-portable, ...).
this is also not a question with any simple or easy answer.
in MS-DOS, you essentially have to write a driver for whatever sound HW
happens to be in the system.
for DOS apps in Windows, one has to target whichever HW Windows is faking

Re: [OT] "claim", etc. (was Re: C Standard Regarding Null Pointer Dereferencing)

2010-07-31T21:53:20Z

This is not implausible. Ironically, it took me years of study to
start picking up connotations.
While it's true that connotations are often cultural, I am not aware
of any culture in which accusing someone of having invented something
when they cite to a text as showing it does not constitute an
accusation of dishonesty. I have spoken with English-speakers from

Re: file functions

2010-07-31T21:59:27Z

On Sat, 31 Jul 2010 15:05:03 -0400, "Bill Cunningham"
Here's a start:
fseek need not read anything from the stream. If it does, it
won't be addresses.
fseek need not start from the origin (even after you decide
what you think origin means).
None of the functions change the file pointer at all.

Re: manipulate fd underlying stream

2010-07-31T21:50:07Z

Because if everything can be on every possible topic, topics become
meaningless and we can't find discussions that interest us anymore.
-s

Re: Why is it not possible to assign a global variable to another global variable..?

2010-07-31T21:31:54Z

On Sat, 31 Jul 2010 21:01:24 +0000 (UTC), Jase Schick
The above statements are illegal at file scope.
These are local variables, not global.
Because you don't assign at global scope, you declare:
int i, z; /* declare globals */
int main(int argc, char *argv[])
{
i = 10; /* assign values to globals */

Re: Why is it not possible to assign a global variable to another global variable..?

2010-07-31T21:31:06Z

Initialization and assignment are different things.
int i = 5, j = 6;
is a declaration of 'i' and 'j' as well as an initialization of 'i'
and 'j' with values.
int i, j;
i = 5;
j = 6;
declares 'i' and 'j', then in separate statements assigns (not
initializes) values to those objects.
Try to think about _when_ "global variables" are initialized. In:

Re: Why is it not possible to assign a global variable to another global variable..?

2010-07-31T21:21:46Z

[snip]
Statements are legal only within function bodies.

Re: Proposal for Amendment to Section 6.5.3.2, Unary * Operator

2010-07-31T21:18:37Z

Double-gah. The code example:
struct s;
struct s *sp = NULL;
size_t sz = sizeof *(struct s *)ip;
should instead read:
struct s;
struct s *sp = NULL;
size_t sz = sizeof *sp;