Frustration with tutorial.

I got the book "C for Dummies volume II". printed in 1997. I'm using the djgpp compiler.

It seems that djgpp doesn't recognize the 'strcmpi' function though it recognize 'strcmp'.

Also while doing a small metric program that converts miles to kilometers, I get this:

Code:

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Microsoft Windows 2000 [Version 5.00.2195]
(C) Copyright 1985-2000 Microsoft Corp.

C:\Documents and Settings\Bob L Woods>cd c:\djgpp

C:\DJGPP>cd mystuff

C:\DJGPP\Mystuff>gcc metric.c -o metric
Cannot load VDM IPX/SPX support
metric.c:14:9: warning: unknown escape sequence: '\040'
metric.c: In function 'main':
metric.c:5: warning: return type of 'main' is not 'int'

C:\DJGPP\Mystuff>metric
Enter a value in miles:18
0.00 miles work out to 0.00 kilometers
C:\DJGPP\Mystuff>

---

Here is the source code:

Code:

---

void main()
{
        char input[20];
        double miles,kilometers;

        printf("Enter a value in miles:");
        miles=atof(gets(input));

        kilometers=miles*1.609;

        printf("%.2f miles work out to\ %.2f kilometers",miles,kilometers);
}

---

Can anyone tell me if its something I'm doing wrong or if perhaps my copy of DJGPP is missing files or corrupted?

strcmpi() is non-standard.

For the love of Pete, can you use Visual Studio? There are free versions now and everything.
Oh, and before someone else says it, main should return int, not void (which djgpp is nicely letting you know!)

Code:

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int main()
{
  return 0;
}

---

Code:

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metric.c:5: warning: return type of 'main' is not 'int'

---

Code:

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void main()

---

Does this tell you anything? No? Well, it should, because void main is undefined.

> For the love of Pete, can you use Visual Studio? There are free versions now and everything.
Why? That's got nothing to do with his problem -- using VS wouldn't solve it either.

ok I'm not worried about the warnings. thanks for letting me know about the strcmpi being non standard. It's stricmp for standard right?

Anyways, it still doesn't tell me why this particular program will not work. Any help anyone could give would be nice.

I'll look into the Visual Studioo free version. Is it crippled in some way?

Avoid void main.
Yes, the free version is somewhat crippled. No MFC, no resource editor being the biggest you new programmers. Don't worry, it's still plenty useful.

Referring to your "Cannot load VDM IPX/SPX support" problem, a quick google search for that exact string turned up this: http://rumkin.com/reference/problems/csnw.php

The rest of your problems would be solved by writing proper code I suspect:

Code:

---

#include <stdio.h>
#include <stdlib.h>

int main(void)
{
        char input[20];
        double miles, kilometers;

        printf("Enter a value in miles:");
        miles = atof(gets(input));

        kilometers=miles*1.609;

        printf("&#37;.2f miles work out to %.2f kilometers",miles,kilometers);

        return 0;  // [edit] Hah, forgot the return 0 -- what do I know about proper code??? [/edit]
}

---

Do not use gets. It is incredibly unsafe. Use fgets.

sigh

Code:

---

#include <stdio.h>

int main()
{
  char input[20];
  double miles,kilometers;

  printf("Enter a value in miles: ");
  fflush(stdout);
  if ( fgets(input, sizeof input, stdin) )
  {
      if ( sscanf(input, "%lf", &miles) == 1 )
      {
        kilometers = miles * 1.609;
        printf("%.2f miles work out to %.2f kilometers",miles,kilometers);
      }
  }
  return 0;
}

/* my output
Enter a value in miles: 17.5
17.50 miles work out to 28.16 kilometers
*/

---

Quote:

---

Originally Posted by Elysia

Avoid void main.
Yes, the free version is somewhat crippled. No MFC, no resource editor being the biggest you new programmers. Don't worry, it's still plenty useful.

---

Ok thanks, took a peek and I'll clean that crap out a little later.

It's odd, because this works:

Code:

---

#include <stdio.h>
#include <stdlib.h>

main()
{
        char       
        AmountDue[20];
        double        amountdue;

        printf("Enter the amount due: ");
        scanf("&#37;s",AmountDue);

        amountdue=atof(AmountDue);
        printf("The amount due is '%s' -> %g\n",AmountDue, amountdue);

}

---

But the first posted code acts like I've put in a non-numerical string, with nothing to convert to float.

Quote:

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Originally Posted by A34Chris

It's odd, because this works:

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And what will happen with this "working" code if the user inputs string of 40 characters?

Quote:

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Originally Posted by vart

And what will happen with this "working" code if the user inputs string of 40 characters?

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Buffer overflow obviously. But its just a tut to get you acquainted with things.

Quote:

---

Originally Posted by Dave_Sinkula

Code:

---

#include <stdio.h>

int main()
{
  char input[20];
  double miles,kilometers;

  printf("Enter a value in miles: ");
  fflush(stdout);
  if ( fgets(input, sizeof input, stdin) )
  {
      if ( sscanf(input, "%lf", &miles) == 1 )
      {
        kilometers = miles * 1.609;
        printf("%.2f miles work out to %.2f kilometers",miles,kilometers);
      }
  }
  return 0;
}

/* my output
Enter a value in miles: 17.5
17.50 miles work out to 28.16 kilometers
*/

---

---

Thank you. This worked.

Quote:

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Originally Posted by arpsmack

Referring to your "Cannot load VDM IPX/SPX support" problem, a quick google search for that exact string turned up this: http://rumkin.com/reference/problems/csnw.php

---

Thanks. Got rid of tht crap. :)

Hi buddy

here is your program after removing error.

you forgot to include some usefull libraries

Code:

---

# include<stdio.h>
# include<conio.h>
# include<stdlib.h>


main()
{
        char input[20];
        double miles,kilometers;

        printf("Enter a value in miles:");
        miles=atof(gets(input));

        kilometers=miles*1.609;

        printf("%.2f miles work out to\ %.2f kilometers",miles,kilometers);
       
        getch();
}

---

Quote:

---

Originally Posted by sndpchikane

Hi buddy

here is your program after removing error.

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And making new ones...

1. conio.h is not standard - better avoid
2. main should be

int main(void)

3. do not use gets - ever - read FAQ

4. getche not standard - use getchar()

5. main should return int so better add
return 0;
at the end

Quote:

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Originally Posted by A34Chris

Buffer overflow obviously. But its just a tut to get you acquainted with things.

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Yes, but please, do not teach bad practices. Avoid buffer overrun problems, for example.
It's fine to post a dumbed down example, but don't post an example that's outright dangerous, such as those that are prone to buffer overflows.