Any way to take a word as input from stdin ? - Page 15

#211

09-30-08, 06:12 AM

arnuld

> On Mon, 29 Sep 2008 15:16:56 +0100, Ben Bacarisse wrote:

> Please do, or mark it like this:
>
> #ifdef DEBUG
> ...
> #endif
>
> so we know it is not what you are really trying to do.

okay.

> No. A function takes what it must due to its design.
> get_single_word() needs a char ** because its job is to set a char *
> that "does not belong to it". It is passed a pointer to the char *
> that is must set: get_single_word(char **);
>
> Giving get_input() a char *** parameter does not mean that this must be
> passed to get_single_word. You get to say what you pass!

Thanks so much for the technical advice. I will take some time to write
some pseudo code again to get done with the design of the functions first.
I will make a new post with my new pseudo code and discussion of
function design.

#212

09-30-08, 06:17 AM

arnuld

> On Mon, 29 Sep 2008 12:28:59 +0000, James Kuyper wrote:

> What does that have to do with it? what you pass to feof() and ferror()
> is not the value returned by the I/O function. What you pass it is the
> FILE* associated with the stream that you are using the I/O function on.
> The getchar() function is exactly equivalent to getc(stdin); it's
> provided as a separate function from getc() only for convenience. All
> you need to do is check feof(stdin) and ferror(stdin).

I can't, that input character is needed by the program, hence I use ch to
store it. If i use feof(stdin) then I will loose the input and will get
only the integer vale returned by feof or ferror. The input character is
needed because we are storing them

#213

09-30-08, 09:12 AM

Nick Keighley

On 30 Sep, 06:17, arnuld <sunr...@invalid.address> wrote:
> > On Mon, 29 Sep 2008 12:28:59 +0000, James Kuyper wrote:

> > What does that have to do with it? what you pass to feof() and ferror()
> > is not the value returned by the I/O function. What you pass it is the
> > FILE* associated with the stream that you are using the I/O function on.
> > The getchar() function is exactly equivalent to getc(stdin); it's
> > provided as a separate function from getc() only for convenience. All
> > you need to do is check feof(stdin) and ferror(stdin).
>
> I can't, that input character is needed by the program, hence I use ch to
> store it. If i use feof(stdin) then I will loose the input and will get
> only the integer vale returned by feof or ferror.

I'm baffled. Why will you "lose the input"? What does this mean.

> The input character is
> needed because we are storing them

what?

int read_char_and_check (FILE* f)
{
char ch;
ch = getc (f);
if (ch == EOF)
{
if (feof(f))
printf ("end-of-file\n");
else
printf ("error reading file\n");
}
return ch;
}

#214

09-30-08, 11:40 AM

James Kuyper

arnuld wrote:
>> On Mon, 29 Sep 2008 12:28:59 +0000, James Kuyper wrote:
>
>> What does that have to do with it? what you pass to feof() and ferror()
>> is not the value returned by the I/O function. What you pass it is the
>> FILE* associated with the stream that you are using the I/O function on.
>> The getchar() function is exactly equivalent to getc(stdin); it's
>> provided as a separate function from getc() only for convenience. All
>> you need to do is check feof(stdin) and ferror(stdin).
>
> I can't, that input character is needed by the program, hence I use ch to
> store it. If i use feof(stdin) then I will loose the input and will get
> only the integer vale returned by feof or ferror. The input character is
> needed because we are storing them

What are you talking about? Just replace feof(ch) with feof(stdin);
there's no reason why doing so would require you to make any changes to
the line where you write ch=getchar().

#215

09-30-08, 11:55 AM

vippstar

On Sep 30, 11:12 am, Nick Keighley <nick_keighley_nos>
wrote:
>
> int read_char_and_check (FILE* f)
> {
> char ch;
> ch = getc (f);

That's implementation defined, if char is signed and EOF < SCHAR_MIN
or if a value greater than SCHAR_MAX is returned.

> if (ch == EOF)
> {
> if (feof(f))
> printf ("end-of-file\n");
> else
> printf ("error reading file\n");

It doesn't have to be an error. Assuming char is unsigned, EOF == -1,
you'd get the same results for reading UCHAR_MAX and EOF.

> }
> return ch;
> }

It's possible that this return value is never equal to EOF, even if ch
== EOF

#216

09-30-08, 01:17 PM

Nick Keighley

On 30 Sep, 09:12, Nick Keighley <nick_keighley_nos>
wrote:
> On 30 Sep, 06:17, arnuld <sunr...@invalid.address> wrote:
>>
> I'm baffled. Why will you "lose the input"? What does this mean.
>> what?
>
> int read_char_and_check (FILE* f)
> {
> char ch;

int ch; /* doh! */
[..]

#217

09-30-08, 04:28 PM

Barry Schwarz

On Tue, 30 Sep 2008 10:17:10 +0500, arnuld <sunrise>
wrote:

>> On Mon, 29 Sep 2008 12:28:59 +0000, James Kuyper wrote:
>
>> What does that have to do with it? what you pass to feof() and ferror()
>> is not the value returned by the I/O function. What you pass it is the
>> FILE* associated with the stream that you are using the I/O function on.
>> The getchar() function is exactly equivalent to getc(stdin); it's
>> provided as a separate function from getc() only for convenience. All
>> you need to do is check feof(stdin) and ferror(stdin).
>
>I can't, that input character is needed by the program, hence I use ch to
>store it. If i use feof(stdin) then I will loose the input and will get
>only the integer vale returned by feof or ferror. The input character is
>needed because we are storing them

You seem to think that feof or ferror perform some action against the
data in the stream. That is not true. They merely test and report
the status of certain indicators associated with the stream.

#218

10-09-08, 07:49 AM

Tim Rentsch

jellybean stonerfish <stonerfish> writes:

> On Thu, 18 Sep 2008 22:46:07 +0500, arnuld wrote:
>
> > You are wrong. Most Indian students say that you need Windows to run a
> > computer, without Windows you can not use a computer. I have yet to meet
> > a person who uses Linux as his daily use OS.
> >
> >
> >
>
> Off topic, but what the hell. I, living in Southern California, have yet
> to meet anybody who uses linux. Besides myself, and people I have given
> computers to. I work in construction, and have been in many offices, and
> have seen nothing but window and mac boxes. Eventually, if my children
> let me have some free time, I will join a LUG.

Linux is alive and well in Pasadena and the San Gabriel Valley.
Check SGVLUG - in fact there is a meeting tomorrow night (the
second Thursday of each month), and drop-ins are welcome.

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