function

[pete]

Re: function

santosh wrote:

Bill Cunningham wrote:

>Earlier in this
>post I wanted to write zeros to a file and found out the proper use
>was with the string terminating character '\0' which is a byte with
>all the bits turned off.

>
Not necessarily. It's just a byte with value zero.

Bill is right, you are wrong.

5.2 Environmental considerations
5.2.1 Character sets

A byte with all bits set to 0, called the null character,
shall exist in the basic execution character set;
it is used to terminate a character string literal.

--
pete

[Keith Thompson]

Re: function

"Bill Cunningham" <nospam@nspam.c omwrites:

"Joachim Schmitz" <nospam.jojo@sc hmitz-digital.dewrote in message
news:g1rq2v$nf9 $1@online.de...
>
[snip]
>

>>>Still needs some error checking (num>=0, fp != NULL, fclose and fput
>>>worked)
>>>
>> I can get that part. I think.

>Yep, left as an excercise to the reader 8-)

>
Now here's what I tried in error checking that gave me a warning. I
must've messed up.
>
if((fputc(a,fp) )!=NULL)
if((fclose(fp)) !=NULL)
>
comparing argument with a without a cast or something like that the compiler
said. Without cast and comparing was mentioned by the compiler but it
compiled and didn't work.

"something like that"? Is there some reason you couldn't tell us
*exactly* what the compiler said?

(Incidentally, be wary of any compiler diagnostic that implies a cast
is missing. 99% of the time a cast is exactly the wrong solution.)

So I tried this.
>
if((fputc(a,fp) )==NULL)
puts("fputc error");
>
When I ran the binary fputc error was mentioned 10 times. My 2nd arg was 10.

RTFM. (Read The Fine Manual.)

Read the documentation for fputc, either your system's online
documentation, or your C textbook, or some version or draft of the C
standard. What type does it return? What do different returned
values mean? What value or values does it return to indicate that
there was an error? Does fputc return a pointer type? Does it make
any sense to compare its result to NULL, which is a null pointer
constant?

Repeat the above paragraph, replacing "fputc" with "fclose".

(Don't bother posting the answers here; most of us already know them.)

You're obviously guessing, yet again. Don't do that. Don't even
think about using a function until you've read and understood the
documentation for that function. If your compiler warns you about a
function call, it's very likely that you're using that function
incorrectly; consult the function's documentation *before* (or instead
of) posting here.

And add some whitespace to make your code more readable. You wrote:

if((fputc(a,fp) )!=NULL)

I'd write:

if (fputc(a, fp) != NULL)

Note that I've also dropped an extraneous set of parentheses.

(I just fixed the layout, not the error; I'll leave that to you.)

--
Keith Thompson (The_Other_Keit h) kst-u@mib.org <http://www.ghoti.net/~kst>
Nokia
"We must do something. This is something. Therefore, we must do this."
-- Antony Jay and Jonathan Lynn, "Yes Minister"

[Keith Thompson]

Re: function

santosh <santosh.k83@gm ail.comwrites:

Bill Cunningham wrote:

>"santosh" <santosh.k83@gm ail.comwrote in message
>news:g1s4e8$ig h$3@registered. motzarella.org. ..

[...]

>it didn't work but I guess I've had NULL on my mind. Earlier in this
>post I wanted to write zeros to a file and found out the proper use
>was with the string terminating character '\0' which is a byte with
>all the bits turned off.

>
Not necessarily. It's just a byte with value zero.

Which, for all practical purposes, *is* a byte with all the bits
turned off.

(If plain char is signed, and if it has more than one representation
of zero, it's conceivable that storing '\0' in a char object might
give it a representation other all-bits-zero -- but even in such an
implementation, I'd be astonished if it didn't choose the
all-bits-zero representation. )

Incidentally, it's true that '\0' is used to terminate a string, but I
don't think that's relevant in this case. You're writing zero bytes
to a binary file. The data isn't being treated as a string or
strings, so the fact that '\0' happens to be a string terminator isn't
relevant.

[...]

--
Keith Thompson (The_Other_Keit h) kst-u@mib.org <http://www.ghoti.net/~kst>
Nokia
"We must do something. This is something. Therefore, we must do this."
-- Antony Jay and Jonathan Lynn, "Yes Minister"

[Bill Cunningham]

Re: function


"santosh" <santosh.k83@gm ail.comwrote in message
news:g1s7f0$1ei $1@registered.m otzarella.org.. .

Not necessarily. It's just a byte with value zero.
>

I wrote this program in my djgpp compile not my gcc one and got the
ascii value of 48.

printf("%i\n",' 0');

Bill

[Lew Pitcher]

Re: function

In comp.lang.c, Bill Cunningham wrote:

>
"santosh" <santosh.k83@gm ail.comwrote in message
news:g1s7f0$1ei $1@registered.m otzarella.org.. .
>

>Not necessarily. It's just a byte with value zero.
>>

I wrote this program in my djgpp compile not my gcc one and got the
ascii value of 48.
>
printf("%i\n",' 0');

Right. That's not a "byte with value zero". That's a character with a value
of '0' (much like a character with a value of 'Q').

--
Lew Pitcher

Master Codewright & JOAT-in-training | Registered Linux User #112576
http://pitcher.digitalfreehold.ca/ | GPG public key available by request
---------- Slackware - Because I know what I'm doing. ------

[Keith Thompson]

Re: function

"Bill Cunningham" <nospam@nspam.c omwrites:

"santosh" <santosh.k83@gm ail.comwrote in message
news:g1s7f0$1ei $1@registered.m otzarella.org.. .
>

>Not necessarily. It's just a byte with value zero.
>>

I wrote this program in my djgpp compile not my gcc one and got the
ascii value of 48.
>
printf("%i\n",' 0');

'0' and '\0' are two very different things.

--
Keith Thompson (The_Other_Keit h) kst-u@mib.org <http://www.ghoti.net/~kst>
Nokia
"We must do something. This is something. Therefore, we must do this."
-- Antony Jay and Jonathan Lynn, "Yes Minister"

[CBFalconer]

Re: function

Bill Cunningham wrote:

>

.... snip ...

>
I wrote this program in my djgpp compile not my gcc one and got
the ascii value of 48.

The DJGPP compiler IS gcc.

--
[mail]: Chuck F (cbfalconer at maineline dot net)
[page]: <http://cbfalconer.home .att.net>
Try the download section.


** Posted from http://www.teranews.com **

[Barry Schwarz]

Re: function

On Sat, 31 May 2008 16:16:25 GMT, "Bill Cunningham" <nospam@nspam.c om>
wrote:

>
>"Joachim Schmitz" <nospam.jojo@sc hmitz-digital.dewrote in message
>news:g1rq2v$nf 9$1@online.de.. .
>
>[snip]
>

>>>Still needs some error checking (num>=0, fp != NULL, fclose and fput
>>>worked)
>>>
>> I can get that part. I think.

>Yep, left as an excercise to the reader 8-)

>
Now here's what I tried in error checking that gave me a warning. I
>must've messed up.
>
>if((fputc(a,fp ))!=NULL)
>if((fclose(fp) )!=NULL)

What is the return type of fputc and fclose? What is the type of
NULL? Is there any implicit conversion between the two types? Why do
you think either function returns NULL on error? Do you have a
reference text of any kind? Have you downloaded any of the free
standard drafts (they all provide complete prototypes for every
standard function)? Somewhere along the line you determined that
fputc takes an int and a FILE*. How come you cannot use the same
source to determine its return type?

>
>comparing argument with a without a cast or something like that the compiler

What do you mean "something like that"? You are not a novice poster,
regardless of your skill at C. What is so prohibitively difficult
that you cannot cut and paste the text of the diagnostic into your
message when asking for help?

>said. Without cast and comparing was mentioned by the compiler but it
>compiled and didn't work. So I tried this.

If it produced a diagnostic that you don't understand, it did not
compile cleanly.

>
>if((fputc(a,fp ))==NULL)
>puts("fputc error");
>
>When I ran the binary fputc error was mentioned 10 times. My 2nd arg was 10.

Your 2nd arg of what? Not fputc, the 2nd arg there is fp, not 10. Not
puts, it only has one arg.

>
>Bill
>

Remove del for email

[Bill Cunningham]

Re: function


"CBFalconer " <cbfalconer@yah oo.comwrote in message
news:4841F7D1.2 A144B83@yahoo.c om...

The DJGPP compiler IS gcc.
>

Oh yes sorry it is. I mean my windows environment compiler not my linux
gcc which I use mostly.

Bill

[Joachim Schmitz]

Re: function

Barry Schwarz wrote:

On Sat, 31 May 2008 16:16:25 GMT, "Bill Cunningham" <nospam@nspam.c om>
wrote:

<snip>

>>
>if((fputc(a,fp ))==NULL)
>puts("fputc error");
>>
>When I ran the binary fputc error was mentioned 10 times. My 2nd arg
>was 10.

>
Your 2nd arg of what? Not fputc, the 2nd arg there is fp, not 10. Not
puts, it only has one arg.

2nd arg to his program, AKA argv[2], obviously (if you look upthread), the
number of null bytes to writen to a file (who's name is given in argv[1])

Bye, JOjo

[Richard]

Re: function

"Bill Cunningham" <nospam@nspam.c omwrites:

"santosh" <santosh.k83@gm ail.comwrote in message
news:g1s7f0$1ei $1@registered.m otzarella.org.. .
>

>Not necessarily. It's just a byte with value zero.
>>

I wrote this program in my djgpp compile not my gcc one and got the
ascii value of 48.
>
printf("%i\n",' 0');
>
Bill

Come on. Please stop trolling.