Printf not printing all data

murjax · 07-10-2009, 09:00 PM

The data in this program comes from a text file. It seems to read fine but when I try to print it only a portion of the data prints. I think I'm overlooking something but I can't put my eye on it.

I have this function reading the data.

Code:

void GetFile (int* EmployNum1, int* Dep1, float* PayRte1, char* Exempt1, int* Hours1, int* EmployNum2, int* Dep2, float* PayRte2, char* Exempt2, int* Hours2, int* EmployNum3, int* Dep3, float* PayRte3, char* Exempt3, int* Hours3, int* EmployNum4, int* Dep4, float* PayRte4, char* Exempt4, int* Hours4)
{
	FILE* spData;
	
	spData = fopen("C:\\employeefile.txt", "r");
	if (spData == NULL)
	{
		printf("ERROR\n");
		exit (101);
	}
	while ((fscanf(spData, "%4d%2d%4f%1c%2d%4d%2d%4f%1c%2d%4d%2d%4f%1c%2d%4d%2d%4f%1c%2d", EmployNum1, Dep1, PayRte1, Exempt1, Hours1, EmployNum2, Dep2, PayRte2, Exempt2, Hours2, EmployNum3, Dep3, PayRte3, Exempt3, Hours3, EmployNum4, Dep4, PayRte4, Exempt4, Hours4)) == 1);

While I have this printf statement in main printing.

Code:

printf("%4d %2d %4f %1c %2d", EmployNum1, Dep1, PayRte1, Exempt1, Hours1);

So what's the problem here?

tabstop · 07-10-2009, 09:04 PM

What do you want to have happen? Right now I would guess you're reading in four groups of things and printing out one.

fscanf returns the number of %<whatever> that are matched, so the odds of you actually getting a one, given your format string, are very very low.

MK27 · 07-10-2009, 09:05 PM

Quote:

== 1);

fscanf returns the number of data items successfully read, which it looks like that will be not 1.

murjax · 07-10-2009, 10:17 PM

Quote:

Originally Posted by MK27

fscanf returns the number of data items successfully read, which it looks like that will be not 1.

Well here's the thing, it prints the first 3 items, skips the character item after it, and then prints a few random numbers for the 5th item which was supposed to be a 2 integer number.

**Salem** · 07-10-2009, 10:57 PM

> So what's the problem here?
That the while loop in your function has a ; at the end of it.

So it zooms to the end of the file (or whenever fscanf returns 1 - see MK27's post), and leaves garbage data in anything it doesn't assign.

Oh, and learn about structs, so you can pass 1 pointer to a struct, and not 20 pointers to individual data items.

Also, formatting. You don't need everything on one line.

Code:

fscanf(spData, "%4d %2d %4f"
               "%1c%2d %4d"
               "%2d %4f%1c"
               "%2d %4d %2d"
               "%4f%1c%2d"
               "%4d %2d %4f"
               "%1c%2d",
               EmployNum1, Dep1, PayRte1, 
               Exempt1, Hours1, EmployNum2, 
               Dep2, PayRte2, Exempt2, 
               Hours2, EmployNum3, Dep3, 
               PayRte3, Exempt3, Hours3, 
               EmployNum4, Dep4, PayRte4, 
               Exempt4, Hours4);

brewbuck · 07-11-2009, 11:50 AM

Quote:

Originally Posted by murjax

Well here's the thing, it prints the first 3 items, skips the character item after it, and then prints a few random numbers for the 5th item which was supposed to be a 2 integer number.

Makes sense. You're feeding it garbage, it's printing garbage. The problem is not printf() but how you are reading the data in the first place.

murjax · 07-17-2009, 01:55 PM

Quote:

Originally Posted by brewbuck

Makes sense. You're feeding it garbage, it's printing garbage. The problem is not printf() but how you are reading the data in the first place.

What's the garbage? The contents of the file?

bithub · 07-17-2009, 01:58 PM

Quote:

What's the garbage?

Read Salem's post; he explains where the garbage is coming from.

murjax · 07-20-2009, 10:09 AM

Quote:

Originally Posted by bithub

Read Salem's post; he explains where the garbage is coming from.

Removing the ; from the while statement and changing 1 to the number of items being read (20 in this case) doesn't change a thing.

tabstop · 07-20-2009, 10:20 AM

Well, it changes a lot of things, in the sense that everything (that you've told us about) now works. Apparently you still have some other bug, but you haven't told us about that one yet.

**Salem** · 07-20-2009, 10:22 AM

But posting your latest code might....

murjax · 07-20-2009, 12:19 PM

Here's the current piece of code.

Code:

void GetFile (int* EmployNum1, int* Dep1, float* PayRte1, char* Exempt1, int* Hours1, int* EmployNum2, int* Dep2, float* PayRte2, char* Exempt2, int* Hours2, int* EmployNum3, int* Dep3, float* PayRte3, char* Exempt3, int* Hours3, int* EmployNum4, int* Dep4, float* PayRte4, char* Exempt4, int* Hours4)
{
	FILE* spData;
	
	spData = fopen("C:\\employeefile.txt", "r");
	if (spData == NULL)
	{
		printf("ERROR\n");
		exit (101);
	}
	while ((fscanf(spData, "%4d%2d%4f%1c%2d%4d%2d%4f%1c%2d%4d%2d%4f%1c%2d%4d%2d%4f%1c%2d", EmployNum1, Dep1, PayRte1, Exempt1, Hours1, EmployNum2, Dep2, PayRte2, Exempt2, Hours2, EmployNum3, Dep3, PayRte3, Exempt3, Hours3, EmployNum4, Dep4, PayRte4, Exempt4, Hours4)) == 20)

	return;
}

I know I haven't structured it properly yet, but I just want to see it work first. If the problem isn't in here then I guess I'll post the whole code even though I thought the rest worked fine.

itCbitC · 07-20-2009, 12:24 PM

How many lines are there in the input file? Is the return statement a part of the while loop?

murjax · 07-20-2009, 12:45 PM

Quote:

Originally Posted by itCbitC

How many lines are there in the input file? Is the return statement a part of the while loop?

There are 4 lines and no, the return isn't supposed to be part of the loop, which is why I originally had a ; at the end of the last line.

MK27 · 07-20-2009, 01:01 PM

Quote:

Originally Posted by murjax

There are 4 lines and no, the return isn't supposed to be part of the loop, which is why I originally had a ; at the end of the last line.

Whoops!

You should throw a printf, including the return value of fscanf, into the while loop so you can see what actually is happening.

07-10-2009, 09:04 PM	#2
tabstop and the Hat of Guessing Join Date: Nov 2007 Posts: 8,740	What do you want to have happen? Right now I would guess you're reading in four groups of things and printing out one. fscanf returns the number of %<whatever> that are matched, so the odds of you actually getting a one, given your format string, are very very low.
tabstop is offline

07-10-2009, 10:57 PM	#5
Salem and the hat of vanishing Join Date: Aug 2001 Location: The edge of the known universe Posts: 21,214	> So what's the problem here? That the while loop in your function has a ; at the end of it. So it zooms to the end of the file (or whenever fscanf returns 1 - see MK27's post), and leaves garbage data in anything it doesn't assign. Oh, and learn about structs, so you can pass 1 pointer to a struct, and not 20 pointers to individual data items. Also, formatting. You don't need everything on one line. Code: fscanf(spData, "%4d %2d %4f" "%1c%2d %4d" "%2d %4f%1c" "%2d %4d %2d" "%4f%1c%2d" "%4d %2d %4f" "%1c%2d", EmployNum1, Dep1, PayRte1, Exempt1, Hours1, EmployNum2, Dep2, PayRte2, Exempt2, Hours2, EmployNum3, Dep3, PayRte3, Exempt3, Hours3, EmployNum4, Dep4, PayRte4, Exempt4, Hours4); __________________ If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut. Up to 8Mb PlusNet broadband from only £5.99 a month!
Salem is offline

07-20-2009, 10:20 AM	#10
tabstop and the Hat of Guessing Join Date: Nov 2007 Posts: 8,740	Well, it changes a lot of things, in the sense that everything (that you've told us about) now works. Apparently you still have some other bug, but you haven't told us about that one yet.
tabstop is offline

07-20-2009, 10:22 AM	#11
Salem and the hat of vanishing Join Date: Aug 2001 Location: The edge of the known universe Posts: 21,214	But posting your latest code might.... __________________ If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut. Up to 8Mb PlusNet broadband from only £5.99 a month!
Salem is offline

07-20-2009, 12:24 PM	#13
itCbitC Registered User Join Date: Oct 2008 Location: TX Posts: 1,262	How many lines are there in the input file? Is the return statement a part of the while loop?
itCbitC is offline

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